CONTENTS

INTRODUCTION ..................................................................................................................1

REGIONAL/OVERVIEW PAPERS.......................................................................................3

HYDROGEOLOGIC MAPPING IN THE BASIN AND RANGE PROVINCE,

PROGRESS SINCE 1900, AND FUTURE PROSPECTS

John W. Hawley.................................................................................................................................................3

PROGRESS REPORT ON GEOPHYSICAL STUDIES FOR THE

MIDDLE RIO GRANDE BASIN PROJECT

V.J.S. Grauch, Maria Deszcz-Pan, and Brian Rodriguez......................................................................................7

MODIFICATION AND UPDATE OF ALBUQUERQUE BASIN

GROUND-WATER-FLOW MODEL

Douglas P. McAda and John Michael Kernodle ................................................................................................10

APPLICATION OF PARAMETER-ESTIMATION METHODS TO THE

GROUND-WATER FLOW MODEL OF THE MIDDLE RIO GRANDE BASIN

Claire R. Tiedeman ..........................................................................................................................................11

USING ENVIRONMENTAL TRACER DATA TO IMPROVE THE U.S. GEOLOGICAL

SURVEY MODFLOW MODEL OF THE MIDDLE RIO GRANDE BASIN

Ward E. Sanford, L. Niel Plummer, and Laura M. Bexfield...............................................................................13

TRACING AND DATING GROUND WATER IN THE MIDDLE RIO GRANDE

BASIN, NEW MEXICO—A PROGRESS REPORT

L. Niel Plummer, Ward E. Sanford, Eurybiades Busenberg, Laura M. Bexfield,

Scott K. Anderholm, and Peter Schlosser..........................................................................................................15

NORTHERN MIDDLE RIO GRANDE BASIN.....................................................................17

GEOLOGY OF THE COCHITI PUEBLO AREA AND THE CERRILLOS UPLIFT

BASED ON GEOLOGIC MAPPING, AIRBORNE AND GROUND

GEOPHYSICS, AND LIMITED SUBSURFACE INFORMATION

David Sawyer, Maria Deszcz-Pan, V.J.S. Grauch, Gary Smith, David Dethier,

Ren Thompson, Scott Minor, Ralph Shroba, Brian Rodriguez, and Andrika Kuhle ............................................17

HYDROGEOLOGIC AND TECTONIC SIGNIFICANCE OF NEW GEOLOGICAL

MAPPING IN THE SANTO DOMINGO BASIN AND ADJACENT JEMEZ MOUNTAINS

Gary A. Smith, Andrika J. Kuhle, and William C. McIntosh .............................................................................19

GEOLOGIC MAPS OF THE OJITO SPRINGS, SAN YSIDRO, SKY VILLAGE NE,

AND JEMEZ PUEBLO 7.5-MINUTE QUADRANGLES: RESULTS OF EDMAP AND

STATEMAP EFFORTS IN THE NORTHWESTERN CORNER OF THE ALBUQUERQUE BASIN

F.J. Pazzaglia, M.L. Formento-Trigilio, J.L. Pederson, A.F. Garcia, D.J. Koning, and C. Toya ..........................21

CHARACTERIZING FAULTS IN THE MIDDLE RIO GRANDE BASIN:

RESULTS FROM THE COCHITI AND SANTO DOMINGO PUEBLOS

Scott A. Minor and Nancy A. Shock.................................................................................................................22

EOLIAN ORIGIN OF SANDY MANTLES ON GENTLY-SLOPING BASALTIC

LAVA FLOWS IN THE PLIOCENE CERROS DEL RIO VOLCANIC FIELD

NEAR SANTA FE, NEW MEXICO—PRELIMINARY FINDINGS

Ralph R. Shroba and Ren A. Thompson............................................................................................................24

LANDSLIDES OF THE LOS ALAMOS 30' X 60' QUADRANGLE,

NORTHERN NEW MEXICO

P.E. Carrara .....................................................................................................................................................25

STREAMFLOW LOSS AND INFILTRATION ALONG THE SANTA FE RIVER

NEAR LA BAJADA, NEW MEXICO, JUNE 26–27, 1997

Carole L. Thomas and Jim Constantz................................................................................................................26
CENTRAL MIDDLE RIO GRANDE BASIN........................................................................ 29

ALBUQUERQUE — A HISTORICAL PERSPECTIVE

Michael P. Stier ...............................................................................................................................................29

Surficial & Subsurface Geology................................................................................................................................31

PRELIMINARY GEOLOGIC MAPPING IN PARTS OF THE SANTA ANA PUEBLO

AND BERNALILLO NW QUADRANGLES, NORTHERN ALBUQUERQUE BASIN

Stephen F. Personius........................................................................................................................................31

SUBSURFACE STRATIGRAPHY, STRUCTURE, AND HYDROGEOLOGIC

FRAMEWORK OF THE SANTA FE GROUP FROM BOREHOLE GEOPHYSICAL

LOGS, NORTHERN ALBUQUERQUE BASIN, NEW MEXICO

Sean D. Connell, Bruce D. Allen, and John W. Hawley.....................................................................................33

EXPRESSION OF FAULTS IN HIGH-RESOLUTION AEROMAGNETIC DATA

NEAR ALBUQUERQUE, NEW MEXICO—PRELIMINARY RESULTS

V.J.S. Grauch...................................................................................................................................................34

PRELIMINARY GEOPHYSICAL RESULTS FROM THE RIO RANCHO AREA,

NEW MEXICO

Maria Deszcz-Pan, Brian Rodriguez, V.J.S. Grauch, Byron D. Stone,

David A. Sawyer, and Victor Labson................................................................................................................36

ELECTROMAGNETIC SURVEYS IN THE RIO GRANDE FLOODPLAIN,

MIDDLE RIO GRANDE BASIN, NEW MEXICO—SECOND-YEAR STATUS

Joseph M. Sterling and James R. Bartolino.......................................................................................................37

98th Street Core .......................................................................................................................................................41

THE 98TH STREET CORE: KEY TO ANALYSIS OF SANTA FE GROUP

STRATIGRAPHY AND HYDROGEOLOGY IN THE CENTRAL

MIDDLE RIO GRANDE BASIN

Byron D. Stone and Bruce D. Allen..................................................................................................................41

PALEOMAGNETIC AND ROCK MAGNETIC STUDIES OF THE UPPER

SANTA FE GROUP: GOALS AND PRELIMINARY RESULTS

M.R. Hudson, Marlo Mikolas, B.D. Allen, and J.W. Geissman .........................................................................46

SEDIMENT AND GROUND-WATER GEOCHEMISTRY OF THE 98TH ST.

DRILL CORE NEAR ALBUQUERQUE, NEW MEXICO

Mark R. Stanton, David J. Grimes, Richard F. Sanzolone, and Steven S. Sutley ................................................47

Recharge/Infiltration & Hydraulic Characteristics..................................................................................................49

EFFECTS OF BASIN-MARGIN STRUCTURE AND STRATIGRAPHY

ON GROUND-WATER RECHARGE IN THE PLACITAS AREA,

NORTHERN ALBUQUERQUE BASIN, NEW MEXICO

Peggy Johnson, William LeFevre, Andrew Campbell, and Brian McPherson ....................................................49

TEMPERATURE PROFILES OF THE AQUIFER SYSTEM UNDERLYING THE RIO

GRANDE, MIDDLE RIO GRANDE BASIN, NEW MEXICO—SECOND-YEAR STATUS

James R. Bartolino...........................................................................................................................................50

USE OF SURFACE-WATER PULSES TO ESTIMATE HYDRAULIC CHARACTERISTICS

OF THE RIO GRANDE ALLUVIUM, ALBUQUERQUE AREA, NEW MEXICO

D. Michael Roark.............................................................................................................................................53

Recharge—Santa Fe River, Bear Canyon, Abo Arroyo Studies.................................................................................55

MEASUREMENTS OF TRIBUTARY, INTER-ARROYO, AND MOUNTAIN-FRONT

RECHARGE ON THE SANTA FE RIVER, BEAR CANYON, AND ABO ARROYO,

NEW MEXICO

Jim Constantz ..................................................................................................................................................55

ENVIRONMENTAL TRACERS OF RECHARGE AT ABO ARROYO, BEAR CANYON,

AND THE SANTA FE RIVER, MIDDLE RIO GRANDE BASIN, NEW MEXICO

David A. Stonestrom and Katherine C. Akstin ..................................................................................................57

THERMAL TRACKING TECHNIQUES TO ESTIMATE STREAMFLOW AND

STREAMBED INFILTRATION ALONG THE EASTERN MIDDLE RIO GRANDE BASIN

Amy E. Stewart, Anne D. Ronan, and Jim Constantz ........................................................................................59
SOUTHERN MIDDLE RIO GRANDE BASIN .....................................................................61

PRELIMINARY GEOLOGIC, HYDROLOGIC, AND AEROMAGNETIC MAPS

OF THE WESTERN THREE-QUARTERS OF THE PUEBLO OF ISLETA,

CENTRAL NEW MEXICO

Florian Maldonado, Dave W. Love, Janet L. Slate, V.J.S. Grauch, Ward E. Sanford,

Matthew Heizler, William C. McIntosh, and Nancy A. Shock ...........................................................................61

PRELIMINARY PALEOSEISMIC ANALYSIS OF A TRENCH ACROSS THE

HUBBELL SPRING FAULT NEAR ALBUQUERQUE, NEW MEXICO

Stephen F. Personius ........................................................................................................................................64

MOUNTAIN-FRONT RECHARGE ALONG THE EASTERN SIDE

OF THE MIDDLE RIO GRANDE BASIN, CENTRAL NEW MEXICO

Scott K. Anderholm .........................................................................................................................................66

PRELIMINARY RESULTS OF AQUIFER-RECHARGE ESTIMATES INTERPRETED

FROM CENTRIFUGE HYDRAULIC PROPERTY MEASUREMENTS,

ABO ARROYO, MIDDLE RIO GRANDE BASIN, NEW MEXICO

Angus M. Lewis and John R. Nimmo ...............................................................................................................69

GIS/DIGITAL INFORMATION ............................................................................................71

THE MIDDLE RIO GRANDE BASIN DIGITAL CARTOGRAPHY PROGRAM

OF THE NEW MEXICO BUREAU OF MINES AND MINERAL RESOURCES

David J. McCraw, Paul W. Bauer, and Glen E. Jones........................................................................................71

USING GIS TO PRODUCE A DIGITAL GEOLOGIC MAP: THE LOS LUNAS

QUADRANGLE, AN EXAMPLE FROM THE MIDDLE RIO GRANDE BASIN,

NEW MEXICO

Janet L. Slate and Nancy A. Shock ...................................................................................................................72

HISTORICAL MAP RESEARCH FOR THE MIDDLE RIO GRANDE BASIN STUDY

Stewart Wright.................................................................................................................................................73

URBAN DYNAMICS OF THE MIDDLE RIO GRANDE BASIN

David J. Hester.................................................................................................................................................74

MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS LAND-USE ANALYSIS MODEL

Mike Corlett and David Abrams.......................................................................................................................76

MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS EXISTING LAND-USE INVENTORY

Shohreh Day and Carol S. Harlan .....................................................................................................................77

DATA PRODUCTION STATUS FOR THE MIDDLE RIO GRANDE BASIN

Laurie Davis ....................................................................................................................................................78

DESIGN AND DEVELOPMENT OF THE MIDDLE RIO GRANDE BASIN

STUDY WEB PAGES

Mark R. Feller..................................................................................................................................................79

ADMINISTRATIVE PAPERS..............................................................................................81

NEW MEXICO’S STATEMAP PROGRAM: GEOLOGIC QUADRANGLE

MAPPING ALONG THE RIO GRANDE WATERSHED

Paul Bauer .......................................................................................................................................................81

NEW MEXICO DISTRICT COOPERATIVE PROGRAM

IN THE MIDDLE RIO GRANDE BASIN, FY98

Dennis G. Woodward.......................................................................................................................................84

MEMORANDUM OF UNDERSTANDING BETWEEN

THE U.S. GEOLOGICAL SURVEY – NATIONAL MAPPING DIVISION AND

THE MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS OF NEW MEXICO

Lee W. Aggers, Stephen J. Burstein, and David J. Hester ..................................................................................85

OVERVIEW OF THE FOCUS 2050 REGIONAL PLAN

Dennis R. Foltz and Stephen Burstein...............................................................................................................88

MIDDLE RIO GRANDE BASIN STUDY

PARTICIPATING ORGANIZATIONS .................................................................................91
FIGURES

1. Geophysical surveys conducted in the Middle Rio Grande Basin..........................................................................8

2. Optimal parameter estimates and approximate, linear 95-percent confidence intervals.

Shaded regions are the reasonable range of values for each parameter.

KLSF is specified as 2.0 ft/day in representation 4 .............................................................................................. 12

3. Sketch showing fault zone components.............................................................................................................. 23

4. Santa Fe River study area data-collection sites near La Bajada, New Mexico...................................................... 27

5. Discharge at TCN1 and TCN2, Santa Fe River near La Bajada. ......................................................................... 28

6. Albuquerque area and detailed maps of the I40S1 and RBRN2 sections. ............................................................ 38

7. Terrain conductivity along the I40S1 and RBRN2 sections. Note the similarity of

conductivity values in the I40S1 section and the contrasts between conductivity

values for different spacings in the RBRN2 section............................................................................................ 39

8. Stratigraphic framework of the 98th Street core-hole site. WT, water table; Q, Quaternary period;

USF, upper unit of the Santa Fe Group; MSF, middle unit of the Santa Fe Group; MSF Atrisco M.,

the Atrisco Member of the middle unit of the Santa Fe Group; VA, valley-border alluvial unit. .......................... 42

9. Depositional environments for three prominent lithofacies in a faulted alluvial-plain setting............................... 43

10. Lithology and geophysical logs for three prominent lithofacies of the 98th Street core......................................... 44

11. Location map of the Albuquerque area showing locations of the temperature profile sites.

BRN, Bernalillo site; COR, Corrales site; PDN, Paseo del Norte site; RBR, Rio Bravo site. ............................... 51

12. Ground-water temperature profiles drawn from data measured in Corrales piezometer

COR02 and Paseo del Norte piezometer PDN01. ............................................................................................... 52

13. Map showing site locations, near Rio Bravo Boulevard in Albuquerque. ............................................................ 54

14. Profiles of water content and pore-water concentrations of chloride and bromide

at distances of 5 and 64 meters from Abo Arroyo along a transect near the eastern

margin of the Middle Rio Grande Basin, New Mexico. ...................................................................................... 57

15. Interarroyo recharge rates inferred from solute profiles along the eastern margin

of the Middle Rio Grande Basin, New Mexico................................................................................................... 58

16. Albuquerque Basin and area where mountain-front recharge was estimated

(modified from McAda, 1996)........................................................................................................................... 67

17. Index map of 7.5-minute quadrangles in the Rio Grande watershed showing

New Mexico Bureau of Mines and Mineral Resources STATEMAP quadrangles

in progress (1998–1999) and (1997–1998), and completed (1994–1997). ........................................................... 82

18. Map showing the Focus 2050 Regional Plan area............................................................................................... 89

19. Timeline showing activities scheduled for the Focus 2050 Regional Plan process............................................... 90

20. Sketch showing functional plan areas related to the Focus 2050 Regional Plan................................................... 90

TABLES

1. Summary of subsurface representations. ............................................................................................................ 11

2. Summary of range, variability, and interpretation of terrain-conductivity values

for sections I40S1 and RBRN2.......................................................................................................................... 40
INTRODUCTION

In 1995, the Water Resources Division (WRD) of the

U.S. Geological Survey (USGS) published initial

ground-water flow models of the aquifer system in

the Albuquerque area that indicated significantly

less water available for municipal consumption than

previously estimated (Kernodle and others, 1995).

Accelerating population growth in the area heightens the concern over water supplies; in the 1990

census, approximately 35 percent (about 565,000

people) of the total population of New Mexico lives

within the Middle Rio Grande Basin (MRGB), and

the proportion increases annually. In 1996 (FY-96),

the USGS launched the 5-year Middle Rio Grande

Basin Study, an inter-Divisional and interagency

investigation, to delineate regional structural and

stratigraphic controls on aquifer extent, and to examine ground-water quality, river-aquifer interactions, and efficacy of recharge.

The major participants in the study are Geologic

Division (GD), WRD, and National Mapping Division (NMD) of the USGS, the New Mexico Bureau

of Mines and Mineral Resources (NMBMMR), the

City of Albuquerque, and the New Mexico Office of

the State Engineer. Additional contributing organizations include University of New Mexico, New

Mexico Institute of Mining and Technology, Middle

Rio Grande Council of Governments (MRGCOG),

and numerous counties and Pueblo Nations.

Geologic mapping by GD, NMBMMR, and the universities (largely funded by the USGS National Cooperative Geologic Mapping Program) is providing

additional information about the stratigraphic and

structural framework of the Santa Fe Group sediments, the principal aquifer units of the basin.

High-resolution airborne geophysical surveys by

USGS identify detailed fault patterns that could not

otherwise be detected due to limited outcrop, and

further serve to characterize hydrologic properties

of subsurface units. The USGS and the City of Albuquerque jointly funded a drill hole at the 98th

Street site to collect a continuous-core sample of

these Santa Fe Group sediments; studies of this core

have provided benchmark information for stratigraphic studies and correlation of geophysical logs

throughout the central Middle Rio Grande basin

(Stone and others, 1998). These results contribute to

an improved ground-water flow model for the basin

that is under development by WRD, the City of Albuquerque, and the New Mexico Office of the State

Engineer. Hydrologic studies by these organizations are investigating aquifer properties, various

components of recharge to the ground-water system, and interactions between the Rio Grande and

the aquifers in order to understand the overall water budget of the system. A joint study between

MRGCOG and NMD is investigating historical patterns of land-use change in the metropolitan areas

and evaluating impacts of various growth scenarios

for the region.

These Proceedings are summaries of work presented at the 2nd Annual Middle Rio Grande Basin

Study Workshop held in Albuquerque, New Mexico, on February 10–11, 1998. The first six papers in

the volume are regional in scope and provide overviews of: hydrogeologic mapping in the Basin and

Range province (Hawley); geophysical studies in the

MRGB (Grauch and others); the initial WRD groundwater flow model (McAda) and techniques that bear

on ground-water flow model calibration including

parameter-estimation methods (Tiedeman), environmental tracer data (Sanford and others), and tracing and dating of ground water (Plummer and others).

The next three sections of the volume include reports of studies in different geographic sectors of

the MRGB. The northern part of the MRGB Study

comprises all of the 1:100,000-scale Los Alamos

sheet, the western part of the Santa Fe sheet, and the

northwestern and northeastern parts of the Albuquerque sheet. Research reported in the first five

papers include studies near the Pueblos of Cochiti,

Santo Domingo, and Jemez—geologic mapping

(Sawyer and others; Smith and others; Pazzaglia and

others), fault characterization (Minor and Shock), and

soil genesis studies (Shroba and Thompson). A landslide inventory encompasses a greater portion of the

Los Alamos sheet (Carrara). Part of a larger study

on recharge in three areas of the MRGB, Thomas and

Constantz report on streamflow loss and infiltration

along the Santa Fe River.

The central part of the MRGB area includes the

principal populated areas of Albuquerque, Bernalillo, and Rio Rancho, and studies in this area are

organized as: Surficial and Subsurface Geology,

and Recharge/Infiltration and Hydraulic Charac-
teristics. Papers on surficial and subsurface geology

report on geologic mapping (Personius), subsurface

stratigraphy, structure, and hydrogeologic framework (Connell and others), faults expressed in aeromagnetic data (Grauch), geophysical results from the

Rio Rancho surveys (Deszcz-Pan and others), and

ground-based electromagnetic surveys to explore

the distribution and geometry of silty-clay layers in

the inner river valley (Sterling and Bartolino). Three

papers report on studies of the 98th Street drill-hole

core: stratigraphy and hydrogeology (Stone and Allen), paleomagnetism and magnetostratigraphy

(Hudson and others), and sediment and ground-water

geochemistry (Stanton and others). Recharge/Infiltration and Hydraulic Characteristics papers include reports on: the effects of structure and stratigraphy on recharge (Johnson and others); temperature

profiles to model hydraulic conductivity and estimate recharge (Bartolino); and the use of surfacewater pulses to estimate hydraulic characteristics

(Roark). Recharge studies in all three geographic

areas of the MRGB are reported from study sites in

Santa Fe River (Los Alamos sheet), in Bear Canyon

(Albuquerque sheet), and in Abo Arroyo (Belen

sheet). Constantz provides an overview of current

studies in these three areas. Stonestrom and Akstin

report on the environmental tracers of recharge, and

Stewart and others use thermal tracking techniques to

estimate infiltration.

Studies of geology in the southern part of the

MRGB, largely within the Belen 100k sheet include

Maldonado and others’ summary of geologic, hydrologic, and aeromagnetic data for the Isleta Pueblo,

and Personius’ report of paleoseismic analysis of

relations exposed by a trench across the Hubbell

Spring fault. Recharge studies along the mountain

front of the Manzanos (Anderholm) and Abo Arroyo

(Lewis and Nimmo) conclude this section.

Digital information and Geographic Information

Systems (GIS) studies are integral to all areas of the

MRGB. McCraw and others report on the digital

cartography program of the NMBMMR. Slate and

Shock describe GIS techniques employed to produce

a digital geologic map database. Historical map

research (Wright) is used by Hester to model changes

and trends in urban land-use patterns. The Middle

Rio Grande Council of Governments (MRGCOG) is

constructing a land-use analysis model (Corlett and

Abrams) and an existing land-use inventory (Day and

Harlan). Davis gives an overview of the data production status of the NMD. The MRGB web page

<http://rmmcweb.cr.usgs.-gov/public/mrgb/>

design and development are discussed by webmaster Feller.

The final section of the volume consists of reports

on administrative aspects of the interagency MRGB

Study and activities of cooperating organizations.

The STATEMAP Program of the NMBMMR covers

the status of geologic mapping along the Rio

Grande watershed (Bauer). Woodward highlights

accomplishments of the jointly funded Cooperative

Program of the New Mexico District of WRD with

various entities in the basin. Aggers and others describe a memorandum of understanding between

NMD and MRGCOG for modeling changes in urban

land-use patterns and future forecasts. Several scenarios for future land-use patterns are modeled by

MRGCOG for their Focus 2050 Regional Plan (Foltz

and Burstein).

REFERENCES

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 94-4251, 114 p.

Stone, B.D., Allen, B.D., Mikolas, Marlo, Hawley, J.W., Haneberg, W.C., Johnson, P.S., Allred, Barry, and Thorn, C.R.,

1998, Preliminary lithostratigraphy, interpreted geophysical logs, and hydrogeologic characteristics of the 98th Street

core hole, Albuquerque, New Mexico: U.S. Geological Survey Open-File Report 98-210, 82 p.
REGIONAL/OVERVIEW PAPERS

HYDROGEOLOGIC MAPPING

IN THE BASIN AND RANGE PROVINCE,

PROGRESS SINCE 1900, AND FUTURE PROSPECTS

John W. Hawley

New Mexico Bureau of Mines and Mineral Resources

New Mexico Institute of Mining and Technology

2808 Central Ave., S.E., Albuquerque, NM 87106

<rcase@admin.nmt.edu>

Making a four-dimensional conceptual model that

accurately portrays the material, genetic, spatial and

temporal attributes of the earth’s outer crust is definitely not a trivial pursuit. Several exemplary human traits characterize a successful geologic mapper: scientific and artistic achievement, perseverance, chutzpah, and, most important, a longstanding love affair with this planet.

Because of the major role that ground water plays in

the use of land and water resources of the Basin and

Range province, hydrogeologists have and always

will be attracted to the region, like bees to honey or

bugs to bait. The early generation of geologic mappers (e.g., Powell, King, Gilbert, Russell, Dutton)

served a nation bent on rapid “settlement” and exploitation of the region’s natural resources in an

era of “manifest destiny.” A solid foundation was

laid, however, in that period of foot, horse, and

steam-powered field transportation for future

“geomappers.” Advances in drilling technology

and local availability of deep-subsurface data after

1900 allowed mapping of basin and valley fills in

the three-dimensional context of modern hydrogeologic models that integrate surface and subsurface information on tectonic framework, stratigraphy and lithofacies distribution. Early (1907–1918)

efforts in hydrogeologic mapping and conceptual

model development in the Basin and Range province are illustrated by U.S. Geological Survey

(USGS) Bulletins, Water-Supply Papers, and Folios

by Bryan, Darton, Lee, Meinzer, Schwennesen, Siebenthal, and others (e.g., Lee, 1907; Siebenthal, 1910;

Meinzer, 1911, 1916, 1917, Meinzer and Kelton,

1912; Meinzer and Hare, 1915; Darton, 1916;

Schwennesen, 1918a, 1918b; Bryan, 1923; and Waring and Meinzer, 1947).

Tolman (1909) recognized the fundamental hydrogeologic distinction between depositional systems

in aggrading basins with internal surface drainage

and those with external surface- and ground-water

discharge (his bolson and semibolson systems). He

(Tolman, 1937) and Kirk Bryan (1909, 1923, 1938)

were among the first to effectively describe the

complex interplay between piedmont-slope and

basin-floor depositional systems (bajada, alluvial

flat, lake, playa, and axial-fluvial) in the context of

the geohydrology and geomorphology of Neogene

fault-block basins. Work initiated in the Rio Grande

rift by Bryan and his students has been of particular

significance in the development of modern conceptual models of aquifer systems of the Middle Rio

Grande Basin (e.g., Bryan and McCann, 1937, 1938;

Upson, 1939; Wright, 1945; Stearns, 1953).

The major scientific and technological breakthroughs during and immediately after World War

II, including development of modern geophysicalsurvey and deep-drilling methods, and advances in

geochemistry, introduced a new era of hydrogeologic system characterization that continues today. Mapping of basin-fill aquifer systems in

southern and central Nevada by G.B. Maxey and

students, in cooperation with the USGS – Water Resources Division (WRD), are representative of work

in the Great Basin prior to 1970 (e.g., Maxey and Jameson, 1948; Maxey and Shamberger, 1961; Dudley

and McGinnis, 1962; Bredehoeft, 1963; Cohen et al.,

1965; Hawley and Wilson, 1965; Maxey and Farvolden, 1965; Cohen, 1966; Maxey, 1968; Mifflin,

1968, 1988). Concurrent studies in the El Paso region

by NMSU, the Texas Water Commission, USGS–

WRD, and City of El Paso illustrate innovations in

subsurface mapping using borehole geophysics and

aquifer geochemistry (Knowles and Kennedy, 1956;

Leggat et al., 1962; Cliett, 1969; Hawley et al., 1969;
King et al., 1971). Hydrogeologic mapping and related hydrologic and geologic investigations in

north-central basins of the Rio Grande rift is exemplified by the work of Bjorklund and Maxwell, 1961;

Spiegel, 1961, 1962; Titus, 1961, 1963; Spiegel and

Baldwin, 1963; and Lambert, 1968.

Recent and future hydrogeologic mapping has been

and will be characterized by the increased availability of high-quality geophysical and geochemical

data, and deep-borehole sample and core logs. The

opportunities generated by the exponentially increasing power of computers, and evolution of numerical modeling and GIS technology already

dominates this era.

In the Basin and Range province, the bridge between the Darton-Meinzer-Bryan-Tolman-Maxey

conceptual world and the present will continue to

be hydrogeologic ground truth. Our surface and underground view of Mother Nature’s hydrologic

systems must now be expressed in units that modelers of ground-water flow systems can understand

and computers can process. The recent improvements in our understanding of subsurface geophysical and geochemical systems, geochronology,

and the definition of hydrostratigraphic units (Seaber, 1988), lithofacies properties, and structural

boundary conditions now allow modelers to effectively join forces with hydrogeologists, geophysicists and geochemists in meeting the incredible water-resource challenges that face Third Millennium

society in this and other arid regions. Recent basic

and applied research that directly relates to hydrogeologic mapping of Rio Grande rift basins is illustrated by the works of Kelley (1977), Bachman and

Mehnert (1978), Cordell (1978), Hawley (1978), Machette (1978), Seager and Morgan (1979), Gile et al.

(1981), Wilson et al. (1981), Birch (1982), Seager et al.

(1984, 1987), Lozinsky (1986, 1994), Anderholm

(1988), Barroll and Reiter (1990), Frenzel and

Kaehler (1990), Mack and Seager (1990), Lozinsky

and Tedford (1991), Haase (1992), Haase and Lozinsky (1992), Hawley and Haase (1992), Hawley and

Longmire (1992), Hawley and Lozinsky (1992), Kernodle (1992), Thorn et al. (1993), Chapin and Cather

(1994), Keller and Cather (1994), Haneberg (1995a,

1995b, 1998), Hawley et al. (1995), Kernodle et al.

(1995), Hansen and Gorbach (1997), and Woodward

and Myers (1997).

REFERENCES

Anderholm, S.K., 1988, Ground-water geochemistry of the Albuquerque-Belen Basin, central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 86-4094, 100 p.

Bachman, G.O., and Mehnert, H.H., 1978, New K-Ar dates and late Pleistocene and Holocene geomorphic history of the

central Rio Grande region, New Mexico: Geological Society of America Bulletin, v. 89, p. 283-292.

Barroll, M.W. and Reiter, M., 1990, Analysis of the Socorro hydrogeothermal system, central New Mexico: Journal of

Geophysical Research, v. B95, p. 21,949-21,963.

Birch, F.S., 1982, Gravity models of the Albuquerque Basin, Rio Grande rift, New Mexico: Geophysics, v. 47, no. 8, p.

1185-1197.

Bjorklund, L.J., and Maxwell, 1961, Availability of ground water in the Albuquerque area, Bernalillo and Sandoval

Counties, New Mexico: New Mexico State Engineer, Technical Report 21, 117 p.

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PROGRESS REPORT ON GEOPHYSICAL STUDIES

FOR THE MIDDLE RIO GRANDE BASIN PROJECT

V.J.S. Grauch, Maria Deszcz-Pan, and Brian Rodriguez

U.S. Geological Survey, Mineral Resources Team

Box 25046, MS 964, Denver, CO 80225

Geophysical studies for the Middle Rio Grande Basin project include acquisition of various types of

geophysical data and interpretation of these data in

conjunction with geologic, seismic, hydrologic, and

other subsurface information. They are designed to

improve the understanding of the subsurface hydrogeology of the Basin and thereby improve the

hydrologic model, especially to the north and south

of Albuquerque where subsurface information is

sparse. We have developed a three-pronged approach to accomplish this goal:

Magnetic studies to locate previously unknown or

better define previously known faults and facies

changes within the basin fill that may control

ground-water flow;

Electrical studies to define the three-dimensional extent of hydrogeologic units in the Santa Fe Group

aquifer system, especially the axial river channel

facies; and

Gravity studies to determine major basement faults

and aid interpretation of the regional structure and

tectonic framework of the Basin.

Magnetic Studies

Closely sampled magnetic maps show variations in

the magnetic properties of surface and subsurface

earth and manmade materials. Variations in the

magnetic properties of earth materials arise primarily from differences in the quantities of magnetic

minerals and their magnetic properties. The maps

also show responses from anthropogenic features,
such as buildings, landfills, and pipelines with cathodic protection.

High-resolution aeromagnetic surveys were conducted north and west of Albuquerque in late 1996

(Rio Rancho and Albuquerque West surveys, Fig. 1),

and south and west of Albuquerque in late 1997

(Kirtland/Sandia and Isleta surveys, Fig. 1). Only

preliminary data are currently available for the 1997

surveys. Images of the 1996 survey data can be

viewed with a web browser at <http://rmmcweb.-

cr.usgs.gov/public/mrgb/airborne.html>.

Maps from the surveys show expressions of faults,

volcanic rocks, and lithologic variations within the

sediments of the Santa Fe Group aquifer system.

The expressions of faults are the most striking, revealing many faults that cannot be observed at the

surface. On the other hand, many exposed faults

are not expressed magnetically. Two general types

of magnetic signatures of faults can be recognized.

One type indicates offset between units of different

magnetic properties. These faults can be used to

help define cells within the hydrologic model of the

basin. The other type indicates lower magnetic values (combined with offset) in a zone surrounding

the fault. The lowered values suggest that the material near the fault is different from the surrounding

material, and perhaps has different permeability.

Two faults that are known hydrologic barriers exhibit the second signature, which suggests a relation

between the magnetic signature and reduced permeability.

Future work includes examination of specific faults

to help determine: (1) the magnetic properties that

give rise to the magnetic signature; (2) the mechanism by which magnetic values are lowered in some

faults; and (3) the relation (if any) between the magnetic signature and hydrologic properties of the

fault. Acquisition of additional high-resolution

aeromagnetic data is in the planning stages.

Figure 1. Geophysical surveys conducted in the Middle Rio Grande Basin.
Electrical Studies

Electrical and electromagnetic methods are used to

examine the electrical resistivity (or its inverse,

electrical conductivity) of the subsurface. Resistivities of unaltered igneous rocks are generally high.

Fracture zones and faults that contain clays or water

reduce the resistivity. Resistivities of poorly consolidated sediments are primarily determined by

rock porosity, the electrical resistivity of the pore

substance, and the presence of certain electrically

conductive minerals, such as clays.

Airborne time-domain electromagnetic (TDEM) and

magnetic data were acquired in early 1997 over the

Rio Rancho and Cochiti survey areas (Fig. 1). Only

preliminary data are currently available. Other

electrical data were acquired on the ground (audiomagnetotelluric and DC resistivity methods) to help

calibrate the results of the airborne survey and to

acquire subsurface resistivity information in developed areas where metal, power lines, and electronic

equipment interfered with the airborne data acquisition. Electrical logs are also available from scattered drill holes in the Rio Rancho survey area, and

from one drill hole in the Cochiti survey area.

The airborne TDEM method has been available for

many years for use primarily in mining exploration.

Its application to mapping subtle resistivity variations due to hydrostratigraphic variations is new

and not well understood. As a result, inversion of

the raw data into a credible picture of earth resistivity with depth has not yet been accomplished. Instead, we have used color maps of the raw data

(voltage responses) to determine the feasibility of

the airborne method to map hydrostratigraphic

units within the Santa Fe Group sediments. These

maps show good correlation between gross patterns

and the general distribution of subsurface lithologic

units determined from drill-hole information. In

particular, the pattern of voltage values in the Rio

Rancho data corresponds well to the lateral distribution of the axial river-channel facies north of Albuquerque.

Future work includes: (1) development of a computer algorithm to invert the raw data into resistivity-depth information; (2) continued calibration

with ground electrical data and borehole resistivity

logs; and (3) lithologic interpretation of and correlation between borehole geophysical logs for comparison with modeled resistivity values.

Gravity Studies

Gravity data reflect variations in rock density that

are primarily a function of rock type. The low density of the poorly consolidated basin fill compared

to the moderate to high densities of the surrounding

bedrock produce a good contrast in gravity values

in the Middle Rio Grande Basin. Steep gravity gradients occur at the edges of the Basin where faults

juxtapose basin fill against bedrock. The lower

gravity values generally correspond to thicker fill.

A previously constructed model of the elevation of

the basin floor (crystalline basement) gives values in

the deepest parts of sub-basins that range from

about 2600 m deep on the south to 4800 m deep on

the north. However, this model was constructed

with earlier gravity data and without benefit of

seismic reflection data that have since been released.

In mid-1997, gravity data were acquired as part of a

project at the University of Texas–El Paso in collaboration with the Middle Rio Grande Basin geophysical studies. The new data, which are not yet

available, fill a large gap in data coverage at the

southwestern part of the Basin and will better define the shape of the Belen basin.

Plans for future work include: (1) collection of more

gravity data to fill in large data gaps; (2) comparison

of basement faults defined by gravity data to those

within the alluvium that are expressed in the magnetic data; and (3) construction of a new model of

the basin floor that uses the new gravity data, constrained by seismic-reflection interpretations and

drill-hole information.
MODIFICATION AND UPDATE OF ALBUQUERQUE BASIN

GROUND-WATER-FLOW MODEL

Douglas P. McAda and John Michael Kernodle

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

Ground water from the Santa Fe Group aquifer

system of the Albuquerque Basin is the main source

of water for municipal, domestic, commercial, and

industrial uses in the basin. About 40 percent of the

population of New Mexico live within the Albuquerque Basin, an area of about 3,060 square miles.

The Rio Grande, which extends the length of the

basin, is the principal source of water for irrigated

agriculture. Because the aquifer system is hydraulically connected to the Rio Grande and water in the

river is fully appropriated, any reduction in flow of

the river caused by ground-water withdrawal must

be compensated by owning water rights on the river

or by augmenting river flow (McAda, 1996, p. 3).

Hydrologic relations between the Rio Grande surface-water system and the Santa Fe Group aquifer

system are complex because of the interaction of

hydrologic boundary conditions, aquifer materials,

aquifer stresses, and system responses. A recently

developed ground-water-flow model of the Albuquerque Basin (Kernodle and others, 1995; Kernodle, in press) has portrayed some of the complexities of the hydrologic system and examined the

effects of stresses on the river-aquifer system. This

U.S. Geological Survey (USGS) model simulated

ground-water flow using 11 layers, 244 rows, and

178 columns, a horizontal grid spacing ranging from

200 meters to 1 kilometer, and layer thickness

ranging from about 6 to 150 meters. Sixty-one stress

periods represented the 1901 to 1995 historical period.

Modifications and updates of the USGS model make

it more functional for parameter-estimation and

time-of-travel studies and as a management tool for

water-resources administration in the basin. The

modifications include a coarser finite-difference

grid, a reduced number of layers, and fewer stress

periods than that of the original (Mike Kernodle,

USGS, written commun., March 7, 1996). As part of

that effort, errors in the original model (as noted by

Kernodle, in press) were corrected and more current

geohydrologic interpretations of the Albuquerque

Basin were incorporated. In addition, more accurate elevations were simulated for boundary features in the Rio Grande valley and several errors in

reported ground-water withdrawal were corrected.

The modified model uses 6 layers, 113 rows, and 60

columns, a horizontal grid spacing ranging from 750

meters to 5 kilometers, and layer thickness ranging

from about 12 to 240 meters. This model uses 29

stress periods to represent 1901 to 1995. The modified model was used to apply parameter-estimation

techniques for model calibration (Tiedeman, 1997),

and to compare computed travel times to water

ages (Sanford and Plummer, 1997).

A cooperative project between the New Mexico Office of the State Engineer and the USGS has been

initiated to update the model for use as a wateradministration tool in the basin. These updates

would include information that is currently being

collected on the river-aquifer system. Several investigations, many of which are described in Bartolino (1997) and in articles included in this volume,

will contribute to model updates. New information

on geologic framework; recharge; ground-water

withdrawal; aquifer hydraulic characteristics; piezometric heads in major pumping areas and immediately below the Rio Grande; canal and drain characteristics; and changes in Rio Grande, canal, and

drain flow through major pumping areas would be

used to update and calibrate the model.

REFERENCES

Bartolino, J.R., (ed.), 1997, U.S. Geological Survey Middle Rio Grande Basin Study—Proceedings of the first annual

workshop, Denver, Colorado, November 12-14, 1996: U.S. Geological Survey Open-File Report 97-116, 91 p.

Kernodle, J.M., in press, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1995,

with projections to 2020—Supplement two to U.S. Geological Survey Water-Resources Investigations Report 94-

4251: U.S. Geological Survey Open-File Report 96-209.
Table 1. Summary of subsurface representations.

Subsurface representation

Basin thickness beneath the Rio Grande

(ft)

West-basin high-K

zone included?

1 1600 No

2 1600 Yes

3 5000 No

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114 p., 1 pl.

McAda, D.P., 1996, Plan of study to quantify the hydrologic relations between the Rio Grande and the Santa Fe Group

aquifer system near Albuquerque, central New Mexico: U.S. Geological Survey Water-Resources Investigations

Report 96-4006, 58 p.

Sanford, W.E. and Plummer, L.N. 1997, Improving the Middle Rio Grande MODFLOW model using MODPATH and

environmental tracers, in Bartolino, J.R., (ed.), U.S. Geological Survey Middle Rio Grande Basin Study—Proceedings of the first annual workshop, Denver, Colorado, November 12-14, 1996: U.S. Geological Survey Open-File

Report 97-116, p. 39-41.

Tiedeman, C.R., 1997, Application of parameter estimation methods to the ground-water flow model of the Middle Rio

Grande Basin, in Bartolino, J.R., (ed.), U.S. Geological Survey Middle Rio Grande Basin Study—Proceedings of the

first annual workshop, Denver, Colorado, November 12-14, 1996: U.S. Geological Survey Open-File Report 97-

116, p. 42.

APPLICATION OF PARAMETER-ESTIMATION METHODS

TO THE GROUND-WATER FLOW MODEL

OF THE MIDDLE RIO GRANDE BASIN

Claire R. Tiedeman

U.S. Geological Survey, Water Resources Division, Branch of Regional Research,

345 Middlefield Road, MS 496, Menlo Park, CA 94025

Parameter-estimation methods are applied to the

ground-water flow model of the Middle Rio Grande

Basin, with the goals of calibrating the model and

comparing estimation results for four different representations of the basin subsurface. The finitedifference model to which parameter estimation is

applied is based on that developed by Kernodle and

others (1995), but has coarser spatial and temporal

discretization. Optimal estimates are obtained by a

nonlinear regression technique that adjusts parameter values such that the sum of squared

weighted differences between simulated and observed hydraulic heads and flows is

minimized. About 900 head measurements

and one flow measurement are included in

the calibration data set. The head data are

from wells located throughout the basin, and

were collected during the years 1949 through

1994. The flow observation is the net flow

during the winter months from the Rio

Grande and riverside drains to the groundwater system between the gaging stations

near Bernalillo and Rio Bravo.

Major hydrologic boundary conditions in the model

include mountain-front and tributary recharge, underflow from adjacent basins, evapotranspiration,

and interaction of the ground-water flow system

with the Rio Grande, canals, and drains. The delineation of the basin hydrogeologic units in the

model is similar to that in the model of Kernodle

and others (1995). In this study, however, four different representations of the subsurface are considered, and model parameters are estimated for each

(Table 1). The high-K (hydraulic conductivity) zone

in the west basin is included in representations 2

and 4 to test the hypothesis that there is a very permeable geologic deposit in this part of the basin that

results in a “trough” in the configuration of the

water table. This “trough” was first inferred by

Bjorklund and Maxwell (1961) and Titus (1963).

Thicker basin deposits (Table 1) are included in representations 3 and 4 to investigate the effects of in-
corporating deep ground-water flow in the simulation.

Model parameters to which the data as a whole are

most sensitive are estimated by the nonlinear regression procedure, whereas the values of the remaining parameters are specified. Estimated parameters include: (1) hydraulic conductivity of the

lower Santa Fe Group (KLSF), the Zia Sand (KLSF-Z),

the middle Santa Fe Group (KMSF), the undivided

upper Santa Fe Group (KUSF1), the undivided axial

channel deposits of the upper Santa Fe Group

(KUSF2), and the river alluvium (KRA); (2) recharge

along the east mountains (REast), the Jemez River

(RJemez), and the Rio Puerco (RPuerco); and (3) the

vertical anisotropy of the basin sediments (AV), defined as the ratio of horizontal to vertical hydraulic

conductivity.

Estimation results indicate that although there are

differences in fit at many observation locations, the overall

match of simulated to observed

hydraulic heads and flows is

similar for each of the four subsurface representations. The

estimates of some hydraulic

conductivity parameters and of

AV, however, differ significantly

among the representations (Fig.

2). All of the parameter estimates are reasonable only when

the west-basin high-K zone is

included in the model (representations 2 and 4). In representations 1 and 3, the estimates

of KUSF1, KMSF, and KLSF-Z are

too large, and the confidence

intervals on KUSF1 and KMSF lie

entirely outside the reasonable ranges of values. In

representations 2 and 4,

which contain the west-basin high-K zone, all of the

parameter estimates and the majority of each confidence interval lie within the realistic ranges. Of

these two representations, however, neither is

clearly preferable. The estimate of KMSF is more

reasonable in representation 4, because it is definitively smaller than the estimate of KUSF1, as is likely

based on information about basin depositional processes. The estimates of KRA and AV are more reasonable in representation 2, because these estimates

and their confidence intervals lie entirely within the

realistic ranges; while in representation 4, the estimates are at the lower end of, and the confidence

intervals extend outside of, these ranges. Although

not shown, the estimates of REast, RJemez, and RPuerco are reasonable, in that for each of the representations the estimates are between about 0.5 and 2.0

times the recharge rates calculated by Kernodle and

Scott (1986) using a water-budget method.

REFERENCES

Bjorkland, L.J., and Maxwell, B.W., 1961, Availability of ground water in the Albuquerque area, Bernalillo and Sandoval Counties, New Mexico: New Mexico State Engineer Technical Report 21, 117 p.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigation Report 94-4251, 114 p.

Kernodle, J.M., and Scott, W.B., 1986, Three-dimensional model simulation of steady-state ground-water flow in the

Albuquerque-Belen Basin, New Mexico: U.S. Geological Survey Water-Resources Investigation Report 84-4353,

58 p.

Figure 2. Optimal parameter estimates and approximate, linear 95-percent confidence intervals. Shaded regions are the reasonable range of values for each parameter. KLSF is specified as 2.0 ft/day in representation 4.
Titus, F.B., Jr., 1963, Geology and ground-water conditions in Eastern Valencia County, New Mexico: Socorro: New

Mexico Bureau of Mines and Mineral Resources Ground-Water Report 7, 113 p.

USING ENVIRONMENTAL TRACER DATA TO IMPROVE

THE U.S. GEOLOGICAL SURVEY MODFLOW MODEL

OF THE MIDDLE RIO GRANDE BASIN

Ward E. Sanford1, L. Niel Plummer1, and Laura M. Bexfield2

1

U.S. Geological Survey, Water Resources Division,

431 National Center, Reston, VA 20192 2

U.S. Geological Survey, Water Resources Division,

4501 Indian School Rd., N.E., Suite 200, Albuquerque, NM 87110

During the summers of 1996 and 1997, groundwater samples were collected from 246 locations

throughout the Middle Rio Grande Basin and analyzed for environmental tracers that include CFCs,

2H, 3H, 18O, 13C, 14C, 34S and SF6, as well as for majorand minor-ion chemistry. These tracers can potentially reveal information about the travel times and

paths of ground water within the Middle Rio

Grande Basin. Such information can prove to be

even more valuable when combined with additional

data such as water levels, and with information

about physical parameters of the ground-water

system such as recharge rates and aquifer transmissivities. Kernodle and others (1995) developed a

numerical ground-water flow model of the Middle

Rio Grande Basin using the U.S. Geological Survey

code, MODFLOW (McDonald and Harbaugh, 1988),

that included measurements and estimates of many

of these physical parameters. The objective of this

work is to use the recently-collected environmental

tracer data to help further constrain a flow model of

the basin that is based on the original model of Kernodle and others (1995). The tracer data that have

been analyzed to date suggest that there is good

potential for improvement of the model.

Deuterium and oxygen-18 can be useful as tracers

when different sources of water give consistently

different concentrations of these isotopes. Such is

the case in the Albuquerque area; water from the

Rio Grande has deuterium concentrations that vary

consistently between –90 and –100‰, yet water recharged along the eastern mountain front has concentrations that are consistently heavier (less negative) than –85‰. Sampling of ground water beneath the City of Albuquerque has shown that the

water west of Louisiana Boulevard generally has

deuterium concentrations lighter than –90‰

whereas water east of that line has values heavier

than –90‰. This suggests that ground water west

of this line originated from the river but ground

water east of the line originated from the mountains. This information, however, should be compared with water levels in the area, which are

physical indicators of flow direction.

Water levels in the Albuquerque area in 1960

(Bjorklund and Maxwell, 1961) showed some drawdown because of pumping, but also displayed overall patterns that likely represented predevelopment

conditions. Water-level contours from 1960 indicate

that water was entering the aquifer system from the

Rio Grande just north of Albuquerque near the

town of Corrales and moving to the west of the

river. The 1960 water-level contours also suggest

that water was recharging from the river and moving south within about a five-mile zone east of the

river. The water-level data are ambiguous, however, as to whether or not river water could have

been moving as far east as Louisiana Boulevard

(about 10 miles east the river). The deuterium and

oxygen-18 data therefore may be independent confirmation that river water is entering the aquifer

system under natural conditions and moving southeastward as far as 10 miles east of the river before

moving in a southwesterly direction back toward

the river. It is unlikely that this effect is due to

pumping because ground waters beneath the eastern section of the city all have preliminary 14C-based

ages of several thousand years. The results of flowmodel simulations (Kernodle and others, 1995) are

inconsistent with this observation of significant

natural recharge from the river, in that they indicate
no recharge should occur from the river under natural conditions.

In order to better understand how river water might

enter the aquifer system under natural conditions

and why the results of Kernodle and others (1995)

might be inconsistent with the environmental tracer

data, we constructed a new, simplified model for

purposes of conducting a sensitivity analysis. A

box-shaped model was made to the dimensions of

the central part of the basin (25 miles by 50 miles by

3000 feet thick) and a river was located on the topcenter column of cells with a gradient similar to that

of the Rio Grande. Values of hydraulic conductivity, mountain-front recharge, and anisotropy were

then varied to see under what conditions some river

water might take a substantial diversion through

the aquifer system. For values of recharge and conductivity similar to the 1995 model, the simple

model produced the same results as the original

model—the Rio Grande gains water over its entire

course. With less mountain recharge (or higher

transmissivities), however, the simple model

showed that some river water diverts through the

aquifer system in a pattern that is very similar to

that observed in the Albuquerque area. This suggests that specified recharge values in the 1995

model are too high (or that conductivity values are

too low).

The fact that recharge and transmissivities can affect

the extent to which river water may be entering the

aquifer system implies that the deuterium data

could be used in a more direct way to help calibrate

an improved model of the basin. Plans are now underway for the use of a general nonlinear regression

model, such as UCODE (Poeter and Hill, in review)

or PEST (Doherty, 1994), in combination with

MODFLOW and MODPATH (Pollock, 1994) in order to use the environmental tracer data to calibrate

the model. Carbon-14-based ages will add additional independent information that will be used in

the calibration procedure. Calibrations with deuterium and 14C data will be done originally assuming

steady-state flow conditions. Transient calibrations

can then be performed for the last 50 years to include drawdown data, and for the last 30,000 years

to include possible changes in recharge through the

end of the last ice age. Other modifications to the

original model are planned, including some grid

refinement and the addition of some lower layers

and zones that will make the model more consistent

with the latest geologic information.

REFERENCES

Bjorklund, L.J., and Maxwell, B.W., 1961, Availability of ground water in the Albuquerque area, Bernalillo and Sandoval Counties, New Mexico: New Mexico State Engineer Technical Report 21, 117 p.

Doherty, J., 1994, PEST: Corinda, Australia; Watermark Computing, 122 p.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque basin, Central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114 p.

McDonald, M.G., and Harbaugh, A.W., 1988, A modular three-dimensional finite-difference ground-water flow model:

U.S. Geological Survey Techniques of Water-Resources Investigations, Book 6, Chapter A1, variously paged.

Poeter, E.P., and Hill, M.C., 1998, Documentation of UCODE, a computer code for universal inverse modeling: U.S.

Geological Survey Water-Resources Investigations Report 98-4080, 120 p.

Pollock, D.W., 1994, User’s guide for MODPATH/MODPATH-PLOT, Version 3: A particle tracking post-processing

package for MODFLOW, the U.S. Geological Survey finite-difference ground-water flow model: U.S. Geological

Survey Open-File Report 94-464, variously paged.
TRACING AND DATING GROUND WATER

IN THE MIDDLE RIO GRANDE BASIN,

NEW MEXICO—A PROGRESS REPORT

L. Niel Plummer1, Ward E. Sanford1, Eurybiades Busenberg1,

Laura M. Bexfield2

, Scott K. Anderholm2, and Peter Schlosser3

1

U.S. Geological Survey, Water Resources Division,

432 National Center, Reston, VA 20192 2

U.S. Geological Survey, Water Resources Division,

4501 Indian School Rd., N.E., Suite 200, Albuquerque, NM 87110 3

Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964

Concentrations of environmental tracers and other

chemical and isotopic substances are being determined in ground water from the Santa Fe Group

aquifer in the vicinity of Albuquerque, New Mexico,

and regionally throughout the Middle Rio Grande

Basin. The analyses include major- and minorelement chemistry, tritium (3H), tritiogenic helium-3

(3He), chlorofluorocarbons (CFCs: CFC-11, CFC-12,

CFC-113), sulfur hexafluoride (SF6), oxygen-18 (18O)

and deuterium (2H) in water, carbon-13 (13C) and

carbon-14 (14C) of dissolved inorganic carbon (DIC),

and other dissolved gases (including dissolved oxygen, nitrogen, argon, helium, neon, and carbon dioxide). These data are being used to: (1) identify

recharge areas; (2) date the young (0- to 50-yr) and

old (>2000-yr) water in the aquifer; (3) trace movement of ground water throughout the Basin; (4) estimate recharge rates; (5) trace Rio Grande river

water and water from the drain and canal system

that has entered the Santa Fe Group aquifer in the

Albuquerque area; and (6) help refine the groundwater flow model (Kernodle and others, 1995) developed for the Albuquerque Basin.

Since June 1996, we collected 246 ground-water

samples from available sources including municipal, domestic, and monitoring wells, springs, and

windmills. In addition to the more complete

ground-water sampling, monthly sampling of the

Rio Grande and adjacent drains and laterals, and

water from Tijeras Arroyo and Bear Canyon was

initiated in January 1997 for CFCs, stable isotopes,

tritium, and major- and minor-element chemistry.

Samples of air and unsaturated-zone gas are being

analyzed quarterly for CFCs, SF6, and 13C of CO2

gas. Ground-water samples collected at all available City of Albuquerque production wells in the

summer of 1997 have been analyzed for stable isotopes. Archived ground-water samples from City of

Albuquerque production wells, water from the Rio

Grande, and precipitation from the 1980s have also

been analyzed for stable isotopes. To date, all

chemical analyses of the ground-water samples are

complete for major- and minor-element composition, dissolved gases, CFCs, stable isotopes, and SF6.

Carbon-14 has been determined on 101 groundwater DIC samples and an additional 80 samples

are currently being analyzed. Tritium/helium-3

(3H/3He) analyses have been completed for 35 water samples collected in June 1996. 3H/3He data will

be obtained on approximately 100 water samples.

The project is near the end of the data-acquisition

phase. Additional samples will be collected in

summer 1998 at all deep-monitoring nests completed since July 1997, and additional water samples

will be collected in selected parts of the Basin. Although the results are still preliminary, we can

make some general observations.

The tritium concentration in 20 water samples from

the Rio Grande averaged 8.4 ± 0.7 (±1σ) TU (tritium

units). CFC-11, CFC-12, and CFC-113 concentrations in 104 samples of surface water from the Rio

Grande and adjacent drains and laterals averaged

109 ± 28, 149 ± 74, and 112 ± 19 (±1σ) percent of the

respective air-water-saturation value, after correction for seasonal temperature variations.

CFC-12 concentrations averaged 30 ± 111 (±1σ) picograms per kilogram (pg/kg) in 45 ground-water

samples from undeveloped areas basin-wide, and

were typically at or below the detection limit of 0.3

pg/kg in many of the waters from rural areas. In

developed areas within and surrounding the City of

Albuquerque, the mean and standard deviation for

CFC-12 concentrations in 98 ground-water samples

were 2300 ± 9400 (±1σ) pg/kg. In many cases, the

CFC concentrations were orders of magnitude

greater than that possible for water in equilibrium

with modern air. Under the eastern third of the

City of Albuquerque up to the adjacent mountain
front, CFC-12 concentrations in most ground-water

samples were below detection. In contrast, CFC-12

was commonly detected in water pumped from

wells open to large intervals of the aquifer located

beneath the western two-thirds of the City of Albuquerque, extending eastward from the Rio Grande.

Analyses of ground-water samples from discrete

depths in the inner valley (floodplain) of the Rio

Grande show high concentrations of CFC-12 at

shallow depths.

Tritium concentrations were less than 0.1 TU in

most ground water throughout the area beneath the

City of Albuquerque, except in the inner valley of

the Rio Grande, where tritium concentrations were

typically 9 to 25 tritium units.

The stable isotopes of water provide a useful tracer

of water sources within the Basin. Delta-2H averages –84.4‰ in 282 ground-water samples, with a

range of –53 to –118‰. Some isotopically depleted

water (–118 to –105‰ in ∆2H) is present in wells

near Rio Rancho, at a production well on the West

Mesa, west of Albuquerque, and at depths of about

300 to 700 ft below the water table at the 98th Street

and Mesa Del Sol piezometer nests, southwest of

Albuquerque. Isotopically enriched water from the

eastern mountain front and Tijeras Arroyo (–70 to –

80‰ in ∆2H) appears to flow south beneath parts of

Kirtland Air Force Base. The most enriched waters

(–65 to –53‰ in ∆2H) are present in the southern

third of the Basin.

Carbon-14 activity of DIC ranges from 123.1 to 3.0%

modern carbon in 101 samples, averaging 47.2 pmc

(percent modern carbon). The unadjusted 14C ages

of DIC in the Albuquerque area are approximately

5000 years. 14C activities are near 100 pmc in DIC of

Rio Grande water, and greater than 100 pmc in

shallow ground water in parts of the inner valley,

and in some shallow wells in the eastern mountain

front. The 14C data indicate that water pumped from

production wells in the inner valley produce mixtures of modern river water and older resident

ground water of the Santa Fe Group aquifer.

Tritium/helium-3 dating of young ground water,

and of the young fraction in mixtures of young and

old water, is possible for some waters in the inner

valley, waters along the mountain front, and shallow ground water in the vicinity of Tijeras Arroyo.

Of the 92 3H/3He samples submitted for analysis

from the summer 1996 sampling, 53 have been

analyzed, and of these, 20 samples have apparently

reliable ages, ranging from 0.3 to more than 30

years. For many of the waters from outside the inner valley and outside areas of modern recharge, 3H

concentrations are extremely low due to groundwater ages greater than 50 years, dilution with old

water, and/or low recharge rates. Furthermore,

many of these waters contain a large excess helium

component. For these waters, the fraction of young

water in the mixture cannot be dated using the

3H/3He method.

CFC-12 may be useful in dating some recharge waters in the inner valley, near Tijeras Arroyo, and

along the mountain front. Using recharge temperatures based on measurements of dissolved nitrogen and argon, and estimated recharge elevations, the mountain-front waters sampled were

probably recharged within the past 30 years. For

example, water from Hubbell Spring on the Hubbell

Bench south of Albuquerque appears to be about 23

years old. Water from a closely-spaced piezometer

nest in the Duranes well-field near the Rio Grande

has a well-defined age gradient based on CFC-12,

that indicates a vertical component of ground-water

velocity of approximately 2.8 ft/yr.

CFC-12 dating is often complicated in the Albuquerque area. Local sources of contamination lead

to apparently young or impossible ages. Dilution

with older CFC-free water pumped from wells with

large open intervals result in apparent ages that are

too old. At this preliminary stage of analysis, many

more waters may be dated with CFC-12 and

3H/3He, but presently there are only five waters codated with 3H/3He and CFC-12 for which the apparent ages agree within 2 years.

REFERENCE

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114p.
NORTHERN MIDDLE RIO GRANDE BASIN

GEOLOGY OF THE COCHITI PUEBLO AREA

AND THE CERRILLOS UPLIFT BASED ON

GEOLOGIC MAPPING, AIRBORNE AND GROUND GEOPHYSICS,

AND LIMITED SUBSURFACE INFORMATION

David Sawyer1, Maria Deszcz-Pan2, V.J.S. Grauch2, Gary Smith3, David Dethier4,

Ren Thompson1

, Scott Minor1, Ralph Shroba1, Brian Rodriguez2, and Andrika Kuhle3

1

U.S. Geological Survey, National Cooperative Geologic Mapping,

Box 25046, MS 913, Denver, CO 80225 2

U.S. Geological Survey, Mineral Resources,

Box 25046, MS 964, Denver, CO 80225 3

Department of Earth and Planetary Sciences, University of New Mexico,

Albuquerque, NM 87131 4

Department of Geology, Williams College, Williamstown, MA 01267

Geologic mapping and geophysical investigations in

the Cochiti Pueblo area provide a better understanding of the geologic framework and hydrogeology in this area southwest of Santa Fe. This information is critical to improving models for groundwater underflow from both the Española basin and

Pajarito Plateau to the north, into aquifers of the

larger Albuquerque ground-water system to the

south. Our new investigations, combined with limited subsurface information from 20 water wells,

provide new insights regarding the Santo Domingo

basin, which forms the critical hydrologic link between the Española and Albuquerque basins.

Geologic mapping in the Cochiti Pueblo area provides stratigraphic, structural and age constraints

for lithologic units relevant to the regional hydrogeologic framework of the Santo Domingo basin.

Natural outcrops rarely expose surface units for

more than a few tens to a hundred meters depth.

Surface knowledge of these stratigraphic units and

offsets along faults, however, allow extrapolation of

subsurface data from wells, and airborne and surface geophysics across much larger areas. The principal geologic units mapped at the surface in the

Cochiti Pueblo area are: (1) unconsolidated Pleistocene surficial deposits of gravel, sand, silt, and clay;

(2) two Pleistocene rhyolite ash-flow tuff members

of Bandelier Tuff erupted from the Valles caldera;

(3) basalt and andesite of the Pliocene Cerros del Rio

volcanic field; (4) rift-filling piedmont and axial Rio

Grande sedimentary deposits of the Santa Fe Group,

extending in age from at least Middle Miocene into

the Pleistocene; (5) Miocene rhyolite, andesite, and

basalt, specifically the Bearhead Rhyolite domes,

lava, and Peralta tuff; (6) pre-rift Eocene-Oligocene

sedimentary, volcanic, and plutonic rocks; (7) Cretaceous sedimentary units deposited in the Western

Interior Seaway; and (8) Triassic-Jurassic units

similar to those of the Colorado Plateau.

A combined airborne geophysical survey using

separate time-domain electromagnetic pulse

(TDEM) and aeromagnetic sensors was flown in

March 1997 near Cochiti Pueblo. The 15 x 20-km

survey consists of lines with a 400-m flight spacing

approximately 120 m above ground level. Preliminary plan maps of TDEM voltages, recorded at different times, show that TDEM response generally

corresponds to grain size of clastic alluvial sedimentary deposits. These results allow us to identify

several distinct domains in the Cochiti Pueblo area

based on different TDEM responses. The northern

limit of the Mancos Shale (a strong conductor) is

distinctive in the subsurface north of the Santa Fe

River canyon, where it is truncated by an ENEtrending structural zone roughly on trend with

projection of the Santa Fe River fault zone. We interpret more resistive units north of this boundary

to reflect a thickening of both Cerros del Rio basalts

and Santa Fe Group sediments. The TDEM data

west of the La Bajada fault zone show that relatively

lower resistivity values correspond to Santa Fe

Group piedmont deposits or to Cochiti Formation

volcaniclastic sediments, whereas relatively higher

resistivity values correspond to axial gravel deposits

of the ancestral Rio Grande. To provide independent calibration for the airborne electromagnetic sur-
vey, we collected six audiomagnetotelluric (AMT)

stations that show a good correlation with lithologic

information from wells and geologic mapping.

Aeromagnetic features in the new Cochiti airborne

survey include the basaltic Cerros del Rio volcanic

field; silicic volcanic units of the Jemez volcanic

field (especially the Bandelier Tuff and Bearhead

Rhyolite); and sedimentary fill of the Santo Domingo basin, including intercalated and faulted basalts. A prominent break in the aeromagnetic pattern parallels the La Bajada fault zone. Numerous

high-amplitude positive and reversed magnetic

anomalies correspond to the many vents and complex stratigraphy of the Cerros del Rio volcanic

field. The western half of the survey contains moderate- to low-intensity anomalies that correspond to

units within the Santa Fe Group sedimentary fill

overlain by reversely magnetized Bandelier Tuff,

and faults that offset these strata. Between the Rio

Grande and the La Bajada fault system, a prominent

magnetic low parallels the La Bajada fault, and local

positive magnetic anomalies indicate basaltic vents

buried beneath the surface of the adjacent La Majada geomorphic surface.

Gravity data (from existing compilations by Cordell

and Keller, supplemented by more recent SAGE

data in Ferguson and others, 1995) show a strong

positive anomaly on the eastern flank of the Rio

Grande rift that has been termed the Cerrillos uplift.

Contrary to previous models, the NW limit of the

Cerrillos uplift does not extend beneath the Cerros

del Rio volcanic field to the prominent St. Peters

Dome basement high on the western side of the

Española Basin. We interpret the gravity data and

geologic map relations to indicate there was no

structural boundary between the southern Española

basin and the Santo Domingo basin prior to eruption of the 2.7–2.3 Ma Cerros del Rio volcanic field.

The basin geometry of the Miocene-Pliocene Rio

Grande rift therefore deviates from that of the modern geomorphic Rio Grande valley in the area of the

poorly defined northeast Santo Domingo basin.

Although late Pliocene to early Pleistocene offset of

as much as 375 m separates the Cerros del Rio basalts across the La Bajada fault zone, the minimum

structural relief from the Cerrillos uplift to the axis

of the southern Española and northern Santo Domingo basins is significantly greater. We believe

these relations show that maximum subsidence in

this part of the Rio Grande rift, adjacent to the Cerrillos uplift, occurred during Miocene through middle Pliocene time before eruption of the Cerros del

Rio volcanic field.

Acknowledgments: We gratefully acknowledge permission to work on Cochiti Pueblo given by Governors of Cochiti Pueblo, the cooperation of the staff

of the Cochiti Environmental Protection Office

(CEPO), and the encouragement of Don Diego Gonzalez.

REFERENCE

Ferguson, John F., Baldridge, W.S., Braile, L.W., Biehler, S., Gilpin, B., and Jiracek, G.R., 1995, Structure of the

Española basin, Rio Grande rift, from SAGE seismic and gravity data: New Mexico Geological Society Guidebook,

46th Field Conference, Geology of the Santa Fe Region, p. 105-110.
HYDROGEOLOGIC AND TECTONIC SIGNIFICANCE OF

NEW GEOLOGICAL MAPPING IN

THE SANTO DOMINGO BASIN AND ADJACENT JEMEZ MOUNTAINS

Gary A. Smith1, Andrika J. Kuhle1, and William C. McIntosh2

1

Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 2

New Mexico Bureau of Mines and Mineral Resources,

801 Leroy Place, Socorro, NM 87801

Geological mapping at 1:24,000 scale on the Santo

Domingo Pueblo, Santo Domingo Pueblo SW,

Cañada, and Cochiti Dam 7.5’ quadrangles, complemented by 40Ar/39Ar geochronology, has led to

refinement and revision of stratigraphic and structural characteristics of the northern Santo Domingo

Basin and the margin of the Jemez Mountains volcanic field.

A greater proportion of coarse, gravelly sediment is

present in this region than was appreciated during

construction of the Kernodle et al. (1995) groundwater-flow model for the Albuquerque basin and

suggests the need for upward revision of hydraulic

conductivities for most model cells by an order of

magnitude (to ~10-2 cm/s). Ancestral Rio Grande

gravel and sand are widespread within the upper

Santa Fe Group, extending as much as 12 km west

of, and at least 5 km east of, the modern river. West

of Cochiti Pueblo, these strata are intercalated with

~6.8 Ma pyroclastic deposits of the Peralta Tuff

Member of the Bearhead Rhyolite and underlie a

~6.96 Ma rhyolite dome. Rather than being a thin

Plio-Pleistocene capping layer, as depicted on previous maps, this facies is at least 500 m thick, thus

occupying a substantial volume of the shallow saturated zone, and indicates the presence of a gravelbedload axial stream at an earlier time than previously maintained by most workers. West of the Rio

Grande, the axial facies interfingers with Peralta

Tuff and uppermost Miocene-lower Pleistocene Cochiti Formation. The Peralta Tuff consists of poorly

consolidated, well to poorly sorted rhyolitic tuff and

lapilli tuff intimately intermingled with poorly

sorted sandy gravel dominated by vitric-rhyolite

clasts. Near fault zones, stratiform chalcedony (and

less common calcite) cementation is prevalent and

reaction of groundwater with volcanic glass may

have caused substantial cementation below the water table. The Cochiti Formation, following usage of

Smith and Lavine (1996), is an at least 500-m-thick

sequence of gravel and sand that is at the surface

over most of western Cochiti and Santo Domingo

Pueblos. Gravel dominates in northern and western

outcrops and cementation is generally minor except

locally near faults. These coarse strata of the Cochiti

Formation are also likely more hydraulically conductive than realized in the Kernodle model, potentially leading to new views of recharge routing from

the Jemez Mountains.

The Santo Domingo Basin comprises the accommodation zone between oppositely tilted Española and

Albuquerque basins. Normal faults at the margins

and within the Santo Domingo Basin face both east

and west to form a nearly symmetrical graben.

Down-to-the-east faults increase in displacement

northward where they eventually form the western,

stepped margin of the Española basin half-graben.

Faults with the opposite displacement sense increase in offset southward into the asymmetrically

east-tilted northern Albuquerque basin. Intrabasinal faults strike NNW at a low angle to the N-S

strike of rift-margin structures and may reflect the

extension direction across the diffuse accommodation zone. “See-saw” subsidence within the Santo

Domingo basin is suggested by westward deflection

of the Rio Grande during the late Miocene and subsequent eastward tilting during the Plio-Pleistocene.

Youngest basin-fill sediment (intercalated with

1.84–1.87 Ma pumice correlated to the San Diego

Canyon ignimbrites, and with 1.61 Ma Otowi Member of the Bandelier Tuff) are restricted to the eastern basin. Partly correlative Pliocene gravel caps a

broad erosion surface whose formation beveled

older strata in the western basin during the period

of eastward tilting. A return to westward tilting in

the northern basin is inferred by prolonged westward migration of the Rio Grande over the past

~300,000 years.

Intrabasinal faults, of greater number, length and

displacement than represented on previous maps,

may partition the aquifer at depth, accounting for

water levels in the western basin that are lower than

the Rio Grande. Preferential calcite or chalcedony

cementation along faults is obvious at many locations and may be more prevalent at depth. A horst
trends obliquely across the basin from NW to SE

near Sile and exposes upper Miocene axial gravel

with abundant Peralta Tuff pumice; axial facies may

not be abundant below the water table in this area.

We hypothesize that the trough in the water table

west of the Rio Grande is caused by the presence

there of a highly transmissive section, including

axial-facies gravel, that conducts Jemez Mountains

recharge southward while being structurally isolated from recharge by the Rio Grande.

Faults in the southeastern Jemez Mountains are

northward continuations of NNW-trending intrabasinal faults and also northeast-striking structures,

not seen farther south, that presumably represent

reactivated Proterozoic fabric. The Jemez lineament, therefore, appears to be a broad zone whose

southeastern margin coincides almost exactly with

southeastern volcanic front of the Jemez Mountains

volcanic field. Nearly rectilinear blocks defined by

NE and NNW striking faults are superimposed on

an overall west-tilted structural domain in the

southern Jemez Mountains. The most prominent of

these downfaulted blocks, which we name the

Bearhead basin, subsided during accumulation of a

nearly 700-m-thick section of 6–7 Ma Miocene lava,

tuff, and sediment within the southern part of the

field. Bearhead Rhyolite volcanism was clearly focused along the NE and NNW striking faults, and

especially at their intersections, with the most voluminous extrusion occurring along the west side of

the Bearhead basin. Hypabyssal intrusions of the

Bland Mining District, including roof pendants of

pre-Jemez sediment (lower Santa Fe Group or Galisteo Formation), are strongly uplifted in the footwall of a prominent NE-striking fault, hence explaining this area of rocks within the volcanic field

that are exposed at anomalously low structural

level.

REFERENCES

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2000: U.S. Geological Survey Water-Resources Investigation Report 94-4251, 114 p.

Smith, G.A., and Lavine, A., 1996, What is the Cochiti Formation? New Mexico Geological Society, Guidebook 47, p.

219-224.
GEOLOGIC MAPS OF THE OJITO SPRINGS, SAN YSIDRO,

SKY VILLAGE NE, AND JEMEZ PUEBLO 7.5-MINUTE QUADRANGLES:

RESULTS OF EDMAP AND STATEMAP EFFORTS

IN THE NORTHWESTERN CORNER OF THE ALBUQUERQUE BASIN

F.J. Pazzaglia, M.L. Formento-Trigilio, J.L. Pederson, A.F. Garcia, D.J. Koning, and C. Toya

Department of Earth and Planetary Sciences, University of New Mexico,

Albuquerque, NM 87131-1116

We mapped a series of connected quadrangles

(Ojito Springs, San Ysidro, Sky Village NE, and Jemez Pueblo) applying current lithostratigraphic

nomenclature of Paleozoic, Mesozoic, and early Cenozoic rocks. We use our mapping to help redefine

Santa Fe Group stratigraphy. We identified numerous new faults, some of which have demonstrable

Quaternary offset, and made detailed descriptions

of Quaternary deposits and landforms.

The northwestern corner of the Albuquerque basin

occupies a strategic hydrologic location as groundwater recharge from the San Juan basin, Sierra

Nacimiento, and Jemez Mountains is focused to the

south and east along the Jemez River corridor. The

structural juxtaposition of the southern Rocky

Mountains (Sierra Nacimiento), Basin and Range

(Rio Grande rift), Colorado Plateau, and Jemez

Lineament enables us to investigate the role that

diverse structures and rocks have on regional surface and ground-water hydrology. Numerous

north- and northeast-striking normal faults that define the northwestern boundary of the Rio Grande

rift separate Mesozoic rocks of the Colorado Plateau

from the west (Ojito Springs) to the east (Jemez

Pueblo). These predominantly dip-slip faults,

which have locally reactivated older Laramide

structures, have both down-to-the-east and downto-the-west offset, resulting in several distinct horst

and graben. Commonly an individual normal-fault

segment with down-to-the-west offset changes to a

down-to-the-east, normal-fault segment across a

short (<0.5 km) distance marked by a left-stepping,

horst-block segment boundary. Primarily in the

Jemez Pueblo quad, offset stream channels characterize such left steps. Where the faults cut basin fill,

they are expressed as both carbonate-cemented resistant topographic spines and erodible clay-rich

gouge valleys. The variable degree of cementation

and associated rock fracturing indicate that faults

can act both as barriers as well as conduits for

ground-water flow.

We map several lithostratigraphic units within the

Santa Fe Group. The Zia Formation (300 m thick) is

the basal unit of the Santa Fe Group. The Zia is

composed of the lower Piedra Parada Member, a

white, yellow and tan eolian and fluvial sub-arkosic

sand and silt, and an upper Chamisa Mesa Member

composed primarily of red, yellow, and white fluvial and playa facies. Locally, the Piedra Parada

Member unconformably overlies a ventifactmantled, Oligocene(?) pediment cut across Early

Cenozoic and older rocks. The Zia Formation is

conformably overlain by the middle Santa Fe Formation (~600 m thick), a tan and yellow, predominantly fluvial sand with a distinct increase in pebble

and cobble content. Coarse tan and buff-colored

fluvial sands and gravel of the upper Santa Fe Formation (approximately 100–200 m thick) conformably overlie the middle Santa Fe Formation. These

coarse-grained deposits include units formerly

mapped as Ceja gravel and Cochiti Formation.

Numerous Quaternary deposits document postSanta Fe Group incision, and can be used to help

reconstruct the genesis of modern surface drainage.

For example, Jemez River deposits are rich in felsic

volcanic and Paleozoic rocks, and are thus petrographically distinct from basalt-rich piedmont

deposits.

Our mapping has identified a paleo-Jemez River

that existed several kilometers to the north and east

of its present location immediately following eruption of the upper Bandelier tephra. The progressive

sweep of the river to the south and west has both

lowered base level and brought it closer to the margin of the Colorado Plateau. This has likely played

an important role in the recent dissection of basinfill sediments and the concomitant southward retreat of La Ceja, the north-facing Zia escarpment in

the Sky Village NE quad.
CHARACTERIZING FAULTS IN THE MIDDLE RIO GRANDE BASIN:

RESULTS FROM THE COCHITI AND SANTO DOMINGO PUEBLOS

Scott A. Minor and Nancy A. Shock

U.S. Geological Survey, National Cooperative Geologic Mapping,

Box 25046, MS 913, Denver, CO 80225

<sminor@usgs.gov>

Hydrologic data indicate that faults can strongly

influence ground-water flow within the Middle Rio

Grande Basin (MRGB) aquifer. Such data suggest

that some faults have low hydraulic conductivity

and act as barriers to ground-water flow (Kernodle

and others, 1995). These data are too sparse, however, to determine the lateral extent of impedimentary faults, and they do not preclude that faults can

act as flow conduits. Geologic studies in the MRGB

and in other extensional aquifer basins indicate that

ground water has flowed, or is flowing, preferentially along faults under favorable physical conditions, sometimes episodically during seismic cycles

(e.g., Sibson, 1990; Mozley and Goodwin, 1995;

Hickman and others, 1997). Thus, both temporal

and spatial variability of fault hydrologic characteristics is expected in the MRGB. To study spatial

hydrologic variability of faults in the MRGB, we

have initiated a basin-wide survey to systematically

measure and document a variety of physical parameters of faults at individual outcrop exposures.

Observations made at exposures of map-scale faults

include: (1) fault-plane strike and dip; (2) rake of

slickenside striae; (3) slip sense and chronology; (4)

fault offset; (5) fault-zone fracture geometry (including foot- and hanging-wall damage zones); (6)

fault-core fabric and composition; (7) fault-zone cement distribution, composition, and thickness; (8)

core and damage-zone widths; (9) footwall and

hanging-wall map units/lithology; (10) wall-rock

bedding attitude(s); and (11) cross-cutting relations

of intersecting faults. Additionally, the ratio of

damage-zone width to total fault-zone width (Fa) is

computed where determinable because this ratio

may indicate fault-zone permeability (Caine and

others, 1996). A narrower range of measurements is

also collected from smaller (mesoscale) faults that

are both adjacent to and isolated from the mapped

faults. Mapping of fault zones, beyond that done by

other project geologists (mainly at 1:24,000 scale),

includes delineating the lateral extents of prominent

fault-zone cements.

These fault data are digitized and added to the

composite geologic map database in ARC/INFO

GIS. Selected fault point data embedded in the GIS

database are used to help delineate several types of

fault line attributes, such as cemented fault-zone

segments. Using field constraints, the fault attributes are extrapolated as far as about 4 km from the

observation points along contiguous fault-line segments. The resulting multiple, overlapping, faultline attributes are defined topologically in

ARC/INFO using the “dynamic segmentation”

functionality. Dynamic segmentation allows for

creating, editing, querying, and displaying multiple

sets of attributes for linear features such as fault

lines, and it permits directional routing along such

features (e.g., ground-water flow paths).

Our survey results show the potential utility of

fault-characterization data to provide qualitative

and semi-quantitative geologic constraints for

ground-water flow models in the MRGB. In the

Cochiti-Santo Domingo Pueblos area, fault characterization provides information needed for accurately modeling fault controls on ground-water flow

where water enters the Santo Domingo sub-basin

aquifer at the northern end of the MRGB. Faults in

the study area are mostly NNW-striking normal

faults that dip mainly to the west on the east side of

the study area, to the east on the west side, and both

directions in between (Smith and Kuhle, 1997; G.A.

Smith, D.P. Dethier, D.A. Sawyer, S.A. Minor, R.A.

Thompson, A.J. Kuhle, and R.R. Shroba, unpub.

mapping, 1997). The faults typically dip 50o–70o and

have slickenside striae with moderate- to high-angle

(70o–90o) southerly rakes. Mapped fault zones,

which commonly consist of a central, highlysheared core enveloped by disrupted mixed zones

and outer, fractured damage zones, range in width

from <1 m to as much as 30 m (Fig. 3). Fa values

computed for about 20 mapped faults in the survey

area are all >0.75 and most are >0.9. Such relatively

wide damage zones suggest that the bulk fault

zones in this area may act more like ground-water

conduits than previously assumed.
The distribution of fault-zone cement varies

both in space and mineralogy. Where present,

cement mostly occurs as intergranular and

fracture-filling silica(?) or carbonate within

sheared mixed-zone lenses of gravel and sand.

Prominent, laterally continuous zones of pervasive, sparry carbonate as reported along

faults elsewhere in the MRGB (e.g., Mozley and

Goodwin, 1995) have only been observed intermittently along the La Bajada fault zone

where it juxtaposes gravel of the Santa Fe

Group. In the central and western parts of the

study area, however, impressive wide (as much

as 100 m) zones of resistant, strata-bound silica(?) or carbonate cement flank one or both

sides of several large faults, including the

southernmost Pajarito fault. These strongly

cemented zones may currently act as groundwater flow barriers. Some of the mixed zones

adjacent to these peripheral cemented zones

have contrasting cement mineralogy, indicating

that some faults in the study area have accommodated episodic, channelized aqueous fluidflow and concomitant cementation.

REFERENCES

Caine, J.S., Evans, J.P., and Forster, C.B., 1996, Fault zone architecture and permeability structure: Geology, v. 24, p.

1025-1028.

Hickman, S.H., Barton, C.A., Zoback, M.D., Morin, R., Sass, J., and Benoit, R., 1997, In-situ stress and fracture permeability along the Stillwater fault zone, Dixie Valley, Nevada: International Journal of Rock Mechanics and Mining

Science, v. 34, no. 3-4, p. 1-10.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water Resources Investigations

Report 94-4251, 114 p., 1 pl.

Mozley, P.S., and Goodwin, L.B., 1995, Patterns of cementation along a Cenozoic normal fault: A record of paleoflow

orientations: Geology, v. 23, p. 539-542.

Sibson, R.H., 1990, Conditions for fault-valve behavior, in Knipe, R.J., and Rutter, E.H., (eds.), Deformation mechanisms, rheology, and tectonics: Geological Society of America Special Publication 54, p. 15-28.

Smith, G.A., and Kuhle, A.J., 1997, Late Cenozoic tectonic history of the northern Santo Domingo basin (abs.): New

Mexico Geology, v. 19, p. 54.

Figure 3. Sketch showing fault zone components.
EOLIAN ORIGIN OF SANDY MANTLES ON

GENTLY-SLOPING BASALTIC LAVA FLOWS IN THE

PLIOCENE CERROS DEL RIO VOLCANIC FIELD

NEAR SANTA FE, NEW MEXICO—PRELIMINARY FINDINGS

Ralph R. Shroba and Ren A. Thompson

U.S. Geological Survey, National Cooperative Geologic Mapping,

Box 25046, MS 913, Denver, CO 80225

Grain-size estimates and the composition of sandy

mantles in the Cerros del Rio volcanic field, New

Mexico, indicate that the sand has an eolian origin.

The sandy mantles consist of very fine- to mediumgrained, quartz-rich sand containing scattered basaltic pebbles and cobbles. Gently-sloping basaltic

lava flows, erupted from numerous local vent complexes, characterize the Pliocene Cerros del Rio volcanic field. These basaltic flows underlie the sandy

mantles, and are the probable source of rubble in

the sandy mantles. Basaltic clasts are incorporated

either by downslope movement from topographic

highs or burrowing. The basaltic lava flows commonly weather to boulder- to granule-size material

that contains only minor amounts of sand and finer

material, none of which is quartz rich. Strong

southwesterly winds may have blown the sand

from former sparsely-vegetated or activelyaggrading floodplain deposits along the Rio Grande

to the Cerros del Rio volcanic field. Some of the siltand clay-size fraction in the sandy mantles may

have been derived from more distant sources. Sheet

erosion and sheetwash remobilize sand, and are the

processes that cause sand deposition in topographic

lows in the lava flows. These characteristics are

similar to those for eolian mantles on basaltic lava

flows in the Cima volcanic field in southern California (Wells and others, 1985; McFadden and others,

1986).

The presence of surface and buried soils formed in

the sand mantles indicates episodic deposition followed by surface stability and soil development.

Shallow (2–3 m thick) stream and road cuts usually

expose two deposits. The upper deposit is commonly about 1.2 m thick. The soil formed in the

upper deposit has a weak argillic (Bt) horizon, about

20 cm thick, that overlies an 80-cm-thick, calcic (Bk)

horizon. The Bk horizon has stage I carbonate morphology in the upper half and stage I and locally

stage II morphology in the lower half. The lower

deposit is similar in character to the upper deposit

and is greater than 0.8–1.8 m thick. Slightly weathered sand at a depth greater than one meter is

mostly very fine to medium (0.05–0.5mm), light

brown to pink (7.5YR 6/4 and 7/4), calcareous, has

loamy sand, loam, and silt loam(?) textures, and

lacks obvious bedding or sedimentary structures.

The soil formed in the lower deposit has a calcic (K)

horizon about 35 cm thick that has stage III carbonate morphology, and is locally overlain by an

eroded argillic horizon about 10 cm thick.

The ages of the above deposits can be estimated by

comparing the clay and carbonate morphology of

the overlying soils with that of soils formed in surficial deposits of known or inferred age in northern

and central New Mexico (Wells and others, 1990;

Machette and others, 1997). The clay and carbonate

morphology of the Cerros del Rio soils suggests that

the upper deposit is latest Pleistocene and may be

about 10,000–20,000 years old. The lower deposit is

probably late Pleistocene and may be about 35,000–

75,000 years old.

REFERENCES

Machette, M.N., Long, Thomas, and Bachman, G.O., 1997, Laboratory data for calcic soils in central New Mexico:

background information for mapping Quaternary deposits in the Albuquerque basin: U.S. Geological Survey OpenFile Report 96-722, 60 p.

McFadden, L.D., Wells, S.G., and Dohrenwend, J.C., 1986, Influences of Quaternary climatic changes on processes of

soil development on desert loess deposits of the Cima volcanic field, California: Catena, v. 13, p. 361-389.

Wells, S.G., Dohrenwend, J.C., McFadden, L.D., Turrin, B.D., and Mahrer, K.D., 1985, Late Cenozoic landscape evolution on lava flow surfaces of the Cima volcanic field, Mojave Desert, California: Geological Society of America

Bulletin, v. 96, p. 1518-1529.
Wells, S.G., McFadden, L.D., and Schultz, J.D., 1990, Eolian landscape evolution and soil formation in the Chaco dune

field, southern Colorado Plateau, New Mexico: Geomorphology, v. 3, p. 517-546.

LANDSLIDES OF THE LOS ALAMOS 30’ X 60’ QUADRANGLE,

NORTHERN NEW MEXICO

P.E. Carrara

U.S. Geological Survey, National Cooperative Geologic Mapping,

Box 25046, MS 913, Denver, CO 80225

Recent surficial geologic mapping in the Los Alamos 30’ x 60’ quadrangle, northern New Mexico, has

identified approximately 150 landslides. An area of

about 5000 km2, the Los Alamos 30’ x 60’ quadrangle

includes Bandelier National Monument, Los Alamos National Laboratory, portions of Santa Fe National Forest, and all or part of ten Indian Pueblos

(Cochiti, Jemez, Pojoaque, San Felipe, San Ildefonso,

Santa Ana, Santa Clara, Santo Domingo, Tesuque,

and Zia ). As used here, the term landslide includes

a wide variety of landforms produced by the slow

to rapid downslope transport of surficial materials

or bedrock by gravity resulting from various mass

movement processes, including falls, flows, slumps,

slides, and combinations thereof. Most of these

landslides were previously unmapped, and range in

size from small rotational slides and earthflows of

about 0.10 km2 to large rotational slides and complex landslides (Varnes, 1978) greater than 10 km2.

Landslide types recognized in the map area include

earthflows, debris flows, rotational and translational

slides, and complex landslides (Varnes, 1978). In

total, landslides cover about 10 percent of the Los

Alamos 30’ x 60’ quadrangle.

A variety of methods were used to identify and map

landslide deposits including compilation from existing geologic maps, analysis of 1:40,000 black and

white aerial photographs, and reconnaissance

fieldwork. Low-sun angle in the early morning and

late afternoon highlighted the subdued topography

of many older landslide deposits and facilitated

field identification. Physical characteristics common to landslides that aided in their identification

include: (1) headwall scarps; (2) hummocky topography, including closed depressions and ponds on

hillsides; (3) bulging landslide toe; (4) deflection of

stream channels by landslide toe; (5) vegetation differences between landslide and adjacent stable areas; (6) bedrock blocks with anomalous dips and

strikes; and (7) intact masses of material downslope

of their sources. Landslide scarp height, morphology, and topographic relief between the head and

toe suggest that many of the larger landslide deposits are more than 100 m thick.

Although landslides occur throughout the Los Alamos 30’ x 60' quadrangle, they are concentrated in

the major canyons. These landslides have formed

on steep slopes where resistant volcanic rocks cap

fine-grained, weakly indurated sedimentary rocks

of low shear strength, such as Santa Fe Group sediments. Previous mapping identified extensive landslide deposits along the Rio Grande in White Rock

Canyon (Smith and others, 1976; Reneau and others,

1995; Reneau and Dethier, 1996a and 1996b; and

Dethier and Reneau, 1996). Equally large, massive

landslides also exist, however, along the Jemez

River in the Cañon de San Diego, Vallecito Creek,

and the Rio Guadalupe and its two major tributaries, the Rio Cebolla and the Rio de las Vacas. In

places, landslides form continuous masses for as

much as 10 km along the valley sides.

Landsliding in the map area probably began in the

mid-Pleistocene and has continued to the present.

Causes of the numerous landslides in the Los Alamos 30' x 60' quadrangle may include: (1) downcutting of the canyons through the Pleistocene volcanic rocks exposing the underlying weakly indurated, sedimentary rocks of low shear strength

(Reneau and Dethier, 1996a); (2) continued downcutting and removal of lateral support during times

of high flow, resulting in the maintenance of steep

slopes; and (3) saturation of bedrock and surficial

deposits, particularly during glacial periods, with

resultant increases in pore pressure and mass

(Reneau and Dethier, 1996a). Additionally, earthquakes may have triggered many of the landslides

because this area is seismically active.
Recognizing landslides is important because natural

and human-induced factors can influence slope stability. The reduction of lateral support, the removal

of vegetation, or an increase in pore pressure could

result in landslide reactivation. Landslide-induced

damming can create a temporary lake that overflows and bursts, flooding downstream areas.

Landsliding in White Rock Canyon dammed the Rio

Grande at least four times between 12,000 and

18,000 14C years ago (Reneau and Dethier, 1996a).

REFERENCES

Dethier, D.P., and Reneau, S.L., 1996, Lacustrine chronology links late Pleistocene climate change and mass movements

in northern New Mexico: Geology, v. 24, p. 539-542.

Reneau, S.L., and Dethier, D.P., 1996a, Late Pleistocene landslide-dammed lakes along the Rio Grande, White Rock

Canyon, New Mexico: Geological Society of America Bulletin, v. 108, p. 1492-1507.

Reneau, S.L., and Dethier, D.P., 1996b, Pliocene and Quaternary history of the Rio Grande, White Rock Canyon, and

vicinity, New Mexico: New Mexico Geological Society Guidebook, 47th Field Conference, p. 317-324.

Reneau, S.L., Dethier, D.P., and Carney, J.S., 1995, Landslides and other mass movements near Technical Area 33, Los

Alamos National Laboratory: Los Alamos National Laboratory Report LA-12955-MS, 48 p.

Smith, R.L, Bailey, R.A., and Ross, C.S., 1976, Geologic map of the Jemez Mountains, New Mexico: U.S. Geological

Survey Miscellaneous Investigations Series Map I-571, scale 1:125,000.

Varnes, D.J., 1978, Slope movement types and processes, in Schuster, R.L., and Krizek, R.J., (eds.), Landslides; analysis

and control: Transportation Research Board Special Report 176, p. 12-33.

STREAMFLOW LOSS AND INFILTRATION

ALONG THE SANTA FE RIVER NEAR LA BAJADA,

NEW MEXICO, JUNE 26–27, 1997

Carole L. Thomas1 and Jim Constantz2

U.S. Geological Survey, Water Resources Division, 1

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110 2

345 Middlefield Road, MS 496, Menlo Park, CA 94025

Hydrologists have recognized the importance of

channel losses in streams of the Rio Grande Basin

since the early 1900’s. In the Rio Grande Basin,

where precipitation is small and water demand is

large due to population growth, channel losses due

to infiltration along stream channels are particularly

important because of their potential to recharge the

ground-water system.

A study to: (1) determine streamflow loss patterns

and estimates of infiltration rates; and (2) apply the

streambed-temperature-profile (stp) method to directly measure infiltration through stream channels

in the Middle Rio Grande Basin, New Mexico, began in October 1995. The field sites instrumented

and studied within the Middle Rio Grande Basin

were the Santa Fe River near La Bajada; Bear Canyon Arroyo in Albuquerque; and Abo Arroyo in the

southern Middle Rio Grande Basin. The purpose of

this paper is to discuss streamflow-loss patterns and

estimated infiltration rates during June 26–27 along

a reach of the Santa Fe River near La Bajada (Fig. 4).

The Santa Fe River has certain characteristics that

make it a desirable study site. Effluent from the

Santa Fe Wastewater Treatment Plant causes this

naturally ephemeral stream to flow perennially

downstream from the treatment plant, thus increasing the opportunity to collect data. The Santa

Fe River channel downstream from the treatment

plant passes through a deep canyon and onto a

gently sloping alluvial valley before intersecting the

Rio Grande. This alluvial valley in the La Bajada

area is of interest as an area of potential recharge to

the ground-water system.

Streamflow measurements are available for the

Santa Fe River from March 1970 to the present at a

site (08317200, TCN1) upstream from La Bajada,

New Mexico (Fig. 4). The daily mean flow averaged
for water years 1970–96 is 0.33 cubic meters per second (m3/s) or 11.6 cubic feet per second (ft3/s). The

daily mean flow for water year 1996 ranged from

0.08 to 13.7 m3/s (2.9 to 483 ft3/s); 96.4 percent of

the daily mean flow values were less than or equal

to 0.54 m3/s (19 ft3/s). Flows greater than 0.54 m3/s

(19 ft3/s) generally are a response to storm events or

May-June releases from an upstream reservoir.

Flow at this station is generally unsteady, with a

pattern of a daily minimum in the late afternoon

and a daily maximum during the night to early

morning hours of a 24-hour cycle.

Two streamflow gages (08317203 and 08317207) installed downstream from the 08317200 site in 1996

allowed collection of streamflow data over two

contiguous channel reaches (Fig. 4). The three

gages, from upstream to downstream, are also

identified as TCN1, TCN2, and TCN4 (Fig. 4). The

distance between TCN1 and TCN2 is approximately

800 m, and the distance between TCN2 and TCN4 is

approximately 1,700 m. The three streamflow gages

were operated from October 1996 through November 1997 for determination of streamflow loss

between the gages. Data collection at TCN2

and TCN4 was discontinued on December 4,

1997.

On June 26, 1997, three stream gagers each

made seven to eight current-meter, streamflow measurements at TCN1, TCN2, and

TCN4 between 0900 and 1600. Investigators

measured the wetted-channel area of the

channel reach between TCN1 and TCN4

about every 2 hours during daylight hours

from 0900 June 26 to 0900 June 27. The current-meter, streamflow measurements were

used to develop stage-discharge rating curves

for each of the three gaging stations for the

June 26–27 period, and they also provided a

method for direct calculation of streamflow

losses between gaging stations. Irrigationreturn flow of less than 0.007 m3/ s (0.25

ft3/s) was estimated to return to the Santa Fe

River between TCN2 and TCN4 from adjacent irrigated fields to the north during the

afternoon of June 26. Seepage from beneath

the root zone of the irrigated fields also may

enter the stream. Therefore, only the channel

reach between TCN1 and TCN2 was free of

ungaged irrigation-water exchanges, and

only discharge calculated from stage data for

this reach are reported here (Fig. 5). Data for

1600 to 1830 on June 26 and 0400 to 0900 on

June 27 are missing because the stage recorded

during these times was outside the limits of the

stage-discharge rating curve. Preliminary estimates

of streamflow loss between TCN1 and TCN2 ranged

from about 0.006 to 0.054 m3/s (0.2 to 1.9 ft3/s) after

adjustment for time of travel. The average time of

travel was estimated to be about 15 minutes based

on velocity measurements at TCN1 and TCN2.

Errors are introduced into the calculation of streamflow losses from several sources and affect the observed range of streamflow losses cited above. Current-meter measurements varied due to the difficulty in reading the depth of water on the rod in the

moving current. The unsteady flow condition necessitates a time-of-travel adjustment that is dependent on water velocity, and water velocity

changes with location of measurement in the cross

section, longitudinally along the stream, and with

time. Also, changes in water temperature affect viscosity, which influences the observed range of calculated streamflow losses (Constantz and others,

1994).

Figure 4. Santa Fe River study area data-collection sites near La

Bajada, New Mexico.
The calculated streamflow losses between TCN1

and TCN2 given above are due to both streambed

infiltration and stream evaporation. Estimated

evaporation is 4.8 to 5.4 millimeters per day (in the

range of 6 x 10-8 meters per second (m/s)) based on

evaporation measurements from saturated sediments at Tijeras Arroyo in Albuquerque on June 26–

27, 1991–93 (Thomas, 1995, p. 17). Measured cross

sections were determined during June 26–27, 1997,

to account for stream surface-area variations due to

streamflow variations. The stream surface area

ranged from 4,693 to 6,113 square meters during

this time. Based on streamflow-loss and streamsurface-area estimates, the streambed infiltration

rates varied from approximately 1 x 10-6 to 7

x 10-6 (m/s) during this

time. No adjustment

for evaporative loss

from the stream surface

was used in the infiltration-rate calculation

because the magnitude

of the evaporation rate

was small compared to

the infiltration rate, and

the uncertainty in the

number of significant

figures for the infiltration rate would have

made an adjustment

unreasonable. These

data suggest that 1 to 6

percent of the measured

streamflow loss was due

to direct evaporation from the stream surface.

Other teams of investigators are conducting related

studies regarding infiltration and potential recharge

in the streambed and upland areas adjacent to the

Santa Fe River near La Bajada. A.E. Stewart, A.

Ronan, and J. Constantz report on streambed infiltration calculated using the stp method in these

proceedings. D.A. Stonestrom and K. Akstin report

results using environmental-tracer methods of investigation in these proceedings. Results not yet

published by J. Nimmo and A. Lewis use a steadystate centrifuge method to determine infiltration

and potential recharge.

REFERENCES

Constantz, J., Thomas, C.L., and Zellweger, G., 1994, Influence of diurnal variations in stream temperatures on streamflow loss and groundwater recharge: Water Resources Research, v. 30, p. 3253-3264.

Thomas, C.L., 1995, Infiltration and quality of water for two arroyo channels, Albuquerque, New Mexico, 1988-92:

U.S. Geological Survey Water-Resources Investigations Report 95-4070, 63 p.

Figure 5. Discharge at TCN1 and TCN2, Santa Fe River near La Bajada.
CENTRAL MIDDLE RIO GRANDE BASIN

ALBUQUERQUE — A HISTORICAL PERSPECTIVE

Michael P. Stier

U.S. Geological Survey, National Mapping Division,

Box 25046, MS 516, Denver, CO 80225

The current character of the City of Albuquerque,

New Mexico, is a result of the unique physical geography of the Middle Rio Grande Basin and a dynamic cultural past. From long before Albuquerque’s official creation in 1706 to the present time,

many events have influenced its existence,

sustainability, and growth.

Native Americans settled in the Albuquerque area

about 9,500 years ago as evidenced by artifacts

found in the area, such as the Clovis point (Simmons, 1982). During this time period, the area had

glacial lakes, which were a vital part of the Imperial

mammoth’s habitat. The Native Americans were

primarily attracted to the area to hunt these large

mammals using Clovis-pointed spears. With food

sources and water nearby, the Native American

population flourished in the region for many years.

In the years that followed, from 5,000 to 1,300 years

ago, various Native American cultures, such as the

Desert and Basket Maker Cultures, occupied the

region. About 1,200 years ago, the Basket Makers

abandoned their pit-houses and occupied aboveground buildings made of puddled adobe or stone

(Simmons, 1982). The Basket Makers eventually

became the Pueblos. The name “Pueblo” is derived

from the Spanish word meaning “town.” Essentially, the entire population of a village lived in one

multistoried apartment building.

Spanish explorers came to New Mexico in the sixteenth century in search of “gold, God, and glory.”

Large numbers of Spanish colonists soon followed

the explorers and settled throughout the territory.

Numerous conflicts arose between the Pueblo, Comanche, and Navajo Native Americans, who had

settled in the area, and the Spaniards. Most of the

conflicts were driven by the Native Americans’ refusal to give up their native religion in favor of the

Spaniards’ Christian faith. One such conflict was

the Pueblo Revolt of 1680 (Simmons, 1982). The

Pueblos fought the Spanish to preserve their social

and political structure, sense of world order, and

cultural identity.

As more colonists came to the area, the desire to

establish Spanish legal settlements increased.

Spaniards wanted to establish these settlements, or

“villas,” in the Middle Rio Grande Valley so that the

settlers would have access to churches, public markets, and social activities. In response to the demand for legal settlements, the provisional governor

of the territory, Don Francisco y Valdez, petitioned

the Spanish government in 1706 to establish the

Bosque Grande as a formal villa (Simmons, 1982).

This “bosque,” which the Spanish called a forest on

the banks of a river, had less than the 30 families

required to charter a villa under Spanish law. Valdez, however, came up with a plan he felt would

increase his chances of getting the villa accepted by

the Spanish government. The man who was to approve Valdez’s application was Viceroy Francisco

Fernandez de la Cueva, the Duke of Alburquerque

(a town in western Spain). In his application, Valdez mentioned that he wanted to establish the villa

in the name of the Duke, and call it “Alburquerque”

(Simmons, 1982). The petition was accepted, and

thus was born the City of Alburquerque. The extra

“r” was dropped from Alburquerque’s spelling in

the 1800's.

Before the actual settlement of Albuquerque, the

Spaniards evaluated the bosque to determine the

most suitable site for the villa. The location selected

had the necessary tillable land, pasture, firewood,

and water that the Spanish law required. The elevation of the site was also high enough in relation to

surrounding land to avoid periodic flooding by the

Rio Grande River. The villa’s location also benefited

by its proximity to natural avenues of travel, such as

the Rio Grande River Valley and Tijeras Canyon.

The Rio Grande River Valley offered the most efficient north-south travel, and Tijeras Canyon formed

a route through the Sandia and Manzano Moun-
tains to the eastern plains (Fitzpatrick and Caplin,

1976).

Shortly after Albuquerque’s location had been selected and plotted, many buildings were erected.

The San Felipe de Neri Church was built first, followed by a house for the priest and government

buildings for local officials (Chilton and others,

1984). Colonists settled close to the new villa, built

their houses, and opened irrigation ditches to newly

planted crops. Since its creation in 1706 to the present, the population of Albuquerque has grown from

252 to 420,000 people (Fitzpatrick and Caplin, 1976).

One of the most significant events in Albuquerque’s

history was the arrival of the railroad in 1880. The

railroad was the catalyst that ultimately caused Albuquerque to become the major metropolitan area

that it is today. With this improved transportation,

many of the natural resources Albuquerque possessed could be sold to distant markets within the

United States. Industries like agriculture, cattle

raising, wool, mining, and textiles prospered with

the arrival of the Atchison, Topeka, and Santa Fe

Railway (Harber, 1989). The railroad brought people from the eastern United States, who found jobs

and settled in the Albuquerque area. In 1909, tuberculosis sufferers came in large numbers seeking the

relief offered by the thin atmosphere and dry climate (Fitzpatrick and Caplin, 1976). As more health

seekers arrived in Albuquerque, the health-care industry became increasingly important. Sanatoriums

were built that specialized in the treatment of lung

ailments. Albuquerque’s high concentration of patients and sanatoriums eventually attracted pulmonary specialists from around the country, enhancing

the city’s reputation as a progressive center of

medicine (Fitzpatrick and Caplin, 1976).

Through the years, new industries contributed significantly to Albuquerque’s growth. During World

War II, for example, the population increased substantially with the addition of military establishments such as Kirtland Air Force Base and Sandia

National Laboratories (Harber, 1989). In the 1960's

and 1970's, electronics and clothing manufacturing

contributed to the growth of the city. Since the

1960's, Albuquerque’s downtown has been revitalized, with the Sunport becoming an international

airport serving 19,000 passengers each day (Fitzpatrick and Caplin, 1976). Highways like Interstates

40 and 25 have accommodated more efficient auto

travel along east-west and north-south corridors.

Industrial growth in health care, computer companies, and telecommunications services has created a

consistently strong influx of people seeking jobs.

Today, the results of these historical events are apparent. The City of Albuquerque has dramatically

increased in population, and the urban area has

grown to 120 square miles (310 km2) of land.

REFERENCES

Chilton, Lance, Chilton, Katherine, Arango, E. Polly, Dudly, Jan, Neary, Nancy, and Stlezner, Patricia, 1984, New

Mexico – A New Guide to the Colorful State: University of New Mexico Press, Albuquerque, New Mexico, p. 235-

262.

Fitzpatrick, George and Caplin, Harvey, 1976, Albuquerque—100 Years in Pictures: Modern Press, Albuquerque, New

Mexico, p. 1-163.

Harber, Nancy, 1989, Albuquerque: Modern Press, Albuquerque, New Mexico, p. 34-57.

Simmons, Marc, 1982, New Mexico: University of New Mexico Press, Albuquerque, New Mexico, p. 12-117.
Surficial & Subsurface Geology

PRELIMINARY GEOLOGIC MAPPING IN PARTS OF THE

SANTA ANA PUEBLO AND BERNALILLO NW QUADRANGLES,

NORTHERN ALBUQUERQUE BASIN

Stephen F. Personius

U.S. Geological Survey, Geologic Hazards Team,

Box 25046, MS 966, Denver, CO 80225

Mapping of surficial and bedrock deposits is underway in the Santa Ana Pueblo and Bernalillo NW

7.5’ quadrangles north of the Jemez River. Bedrock

in these quadrangles consists of Tertiary Santa Fe

Group sedimentary rocks and basalts of Santa Ana

Mesa. Younger surficial deposits include alluvial

fan and colluvial deposits shed off Santa Ana Mesa,

fluvial deposits associated with the Jemez River,

and eolian sands derived from bedrock and surficial

deposits.

The oldest rocks exposed in the map area are mixed

eolian and fluvial facies sandstone that appear to

correlate with the upper part of the lower Santa Fe

Group, Zia Sand Formation of Manley (1978) and

Tedford (1982). In the lower part of the section,

these rocks primarily consist of massively crossbedded to parallel bedded, light gray to very pale

brown, poorly consolidated fine- to coarse-grained

sandstone. Several meter-thick outcrops of weathered volcanic ash in this section in the northeastern

part of the Bernalillo NW quadrangle are similar in

appearance to tephra exposures along U.S. Highway 44 northwest of Loma Barbon and in the northern part of the Loma Machete 7.5’ quadrangle to the

south. Higher in the section, these deposits become

more fluvial, and consist of parallel-bedded pink

siltstone and sandstone, interbedded with eolian

crossbedded sandstone.

The Zia Sand Formation is primarily in fault contact

with overlying middle Santa Fe Group sedimentary

rocks. One possible exposure of a depositional

contact between these units is located about 2 km

southeast of Santa Ana (Old Tamaya) Pueblo in the

Santa Ana Pueblo quadrangle. Here light reddish

brown and tan fine-grained sandstone and minor

red mudstone (middle Santa Fe Group) appear to

conformably overlie massively crossbedded sandstone interbedded with pink siltstone (upper Zia

Sand Formation). Elsewhere, middle Santa Fe

Group rocks consist of similar light reddish brown

and tan fine-grained sandstone, red mudstone, and

minor thin pebbly conglomerate. Poorly preserved

pumice beds may aid in regional correlation of these

rocks.

Middle Santa Fe Group rocks are conformably(?)

overlain by a thick sequence of red to tan sandstone

and conglomerate that underlies the basalts of Santa

Ana Mesa; these coarser grained rocks presumably

are correlative with the upper Santa Fe Group.

They consist of well bedded, poorly indurated

sandstone and pebble to minor cobble conglomerate, interbedded with several well developed paleosols that mark hiatuses in deposition. One prominent pumice bed present near the base of these

rocks may provide chronological control to supplement the late Pliocene age of the Santa Ana Mesa

basalts that cap the stratigraphic section in this area.

A few clast-orientation measurements from upper

Santa Fe conglomerates indicate easterly and southeasterly transport directions. Western and northwestern sources are consistent with clast compositions dominated by Sierra Nacimiento/western Jemez Mountains rocks (pink granite, Mesozoic and

Paleozoic sedimentary rocks, Pedernal Chert, petrified wood, intermediate volcanic rocks). Previous

authors (Smith and others, 1970; Manley, 1978)

mapped the middle and upper Santa Fe Group

rocks in the area as Cochiti Formation, but the

transport directions and clast compositions listed

above are inconsistent with the volcaniclastic nature

of the Cochiti Formation as originally described in

the Santo Domingo basin to the northeast (Smith

and Lavine, 1996).

Surficial deposits flanking Santa Ana Mesa are

dominated by thin deposits of bouldery colluvium

that mantle slopes below the mesa-capping basalts.

Well-developed (stage III and IV) calcic soils

strongly cement these unsorted colluvial mixtures
32

of reworked upper Santa Fe Group sand and gravel

and bouldery basaltic debris. In numerous locations, colluvial mantles and underlying bedrock

deposits have slumped and been remobilized as

debris flows. The underlying Santa Fe Group rocks

are well exposed in the resulting headscarps.

An extensive sequence of moderate to poorly sorted

alluvium forms strath and fill terraces and fans

along intermittent stream channels that drain Santa

Ana Mesa. Alluvial deposits generally become finer

grained and less basaltic downstream; clast rock

types are dominated by reworked Santa Fe Group

sand and gravel and less abundant basaltic cobbles

and boulders. These local alluvial deposits underlie

strath and fill terraces that are 2–20 m above modern drainage channels, and interfinger with and/or

overlie fluvial sediments deposited by the Jemez

River. Thin sheets and small dune fields of eolian

sand of various ages locally cover most alluvial deposits. Eolian deposits are especially common

downwind of large arroyos and in areas underlain

by poorly consolidated deposits of Zia Sand Formation.

Jemez River terraces mostly consist of thin (<5-m

thick) deposits of well rounded cobbly alluvium on

straths cut into the underlying bedrock. Several

well-preserved strath terrace remnants are between

5 and 25 m above the modern river channel, but

isolated outcrops of Jemez River alluvium are as

high as 60 m above the Jemez River in scattered locations. Fill terraces are restricted to ≤5-m-high

Holocene terraces, and remnants of an unusual 18-

to 20-m-thick fill terrace exposed in bluffs along the

north side of the river. The high fill terrace is underlain by sand and gravel lenses and a thick sequence of mottled silty clay that locally contains

fist-sized crystals of authigenic gypsum. At sites

southeast and northwest of Santa Ana Pueblo, the

sand and gravel lenses in the fill sequence contain

an as yet unidentified reworked pumice deposit that

may help in determining the age of this fill sequence.

Structures in bedrock consist of both east- and westdipping, generally north-trending normal faults

associated with the Rio Grande rift. Lack of distinctive marker beds precludes precise measurement of offsets, but most of these structures probably have displacements of less than a few hundred

meters. Faults that offset the basalts of Santa Ana

Mesa are easily mapped on air photos, but most

faults in Santa Fe Group rocks are inconspicuous at

best. One exception is the Santa Ana fault, an eastdipping fault whose prominent surface expression

is enhanced by extensive silica cementation in the

footwall. In places, this cemented zone is as much

as 100 m wide, but the degree of cementation varies

considerably along strike. Most bedrock units tilt

eastward, with dips of 8–15o common in Santa Fe

Group rocks.

REFERENCES

Manley, K., 1978, Geologic map of the Bernalillo NW quadrangle, Sandoval County, New Mexico: U.S. Geological

Survey Geologic Quadrangle Map GQ-1446, scale 1:24,000.

Smith, G.A., and Lavine, A., 1996, What is the Cochiti Formation?, in Goff, F., Kues, B.S., Rogers, M.A., McFadden,

L.D., and Gardner, J.N., (eds.), The Jemez Mountains Region: New Mexico Geological Society 47th Field Conference Guidebook, p. 219-224.

Smith, R.L., Bailey, R.A., and Ross, C.S., 1970, Geologic map of the Jemez Mountains, New Mexico: U.S. Geological

Survey Miscellaneous Investigations Map I-571, scale 1:125,000.

Tedford, R.H., 1982, Neogene stratigraphy of the northwestern Albuquerque basin, in Grambling, J.A., and Wells, S.G.,

(eds.), Albuquerque Country II: New Mexico Geological Society 33rd Field Conference Guidebook, p. 273-278.
33

SUBSURFACE STRATIGRAPHY, STRUCTURE, AND

HYDROGEOLOGIC FRAMEWORK OF THE SANTA FE GROUP

FROM BOREHOLE GEOPHYSICAL LOGS,

NORTHERN ALBUQUERQUE BASIN, NEW MEXICO

Sean D. Connell, Bruce D. Allen, and John W. Hawley

New Mexico Bureau of Mines and Mineral Resources

2808 Central Ave., S.E., Albuquerque, NM 87106

Interpretation of borehole geophysical logs measured for water-supply wells in the Albuquerque

metropolitan area of central New Mexico reveal laterally consistent stratigraphic patterns. Such patterns provide a basis for local differentiation of the

Neogene Santa Fe Group, the principal aquifer for

communities along the Rio Grande Valley. Surface

geologic mapping yields important clues to the distribution of faults and alluvial aquifer units in the

region, but Quaternary alluvium obscures numerous geologic structures. Subsurface data in the Albuquerque metropolitan area, however, are plentiful; municipal water-supply and groundwatermonitoring wells are closely spaced (<3 km) and

drilled to depths of up to 1000 m. Integration of

geologic mapping with borehole geophysical logs,

well-completion reports, and driller’s logs, as well

as examination of cuttings from selected wells delineate faults and hydrostratigraphically significant

facies.

Seven hydrostratigraphic units and twelve lithofacies are classified in the subsurface by stratigraphic

position, lithologic character (primarily texture,

provenance and cementation), age, and environment of deposition. Lithofacies (I-X) are differentiated using driller’s logs, cuttings, and geophysical

logs (Hawley, 1996; Hawley and Haase, 1992), and

are mappable among neighboring wells. Santa Fe

Group Lithofacies are grouped into areally extensive upper (USF), middle (MSF), and lower (LSF)

hydrostratigraphic units that are broadly equivalent

to the informally defined upper buff, middle red,

and lower gray formations of Byran and McCann

(1937). Lucas and others (1993) recently applied the

term Sierra Ladrones Formation to upper buff strata

in the Albuquerque area. These hydrostratigraphic

units contain coarse-grained fluvial (I, III), fluvialeolian sand (II), basin-floor (alluvial-flat) silt, clay

with minor sand (IX, X), and piedmont lithofacies

(V, VI); facies IV, VII and VIII are partly indurated

equivalents of II, V and VIII, respectively. Piedmont

deposits derived from basement-cored, footwall

uplifts along the eastern margin (Sandia and Manzano Mountains) comprise units USF-1 and MSF-1.

Fluvial deposits associated with the ancestral Rio

Grande (having a north-northeastern provenance)

and Rio Puerco (having a north-northwestern

provenance) comprise units USF-2/MSF-2 and USF3/MSF-3, respectively. Units USF-4 and MSF-4

have a western basin-margin provenance. LSF is

predominantly eolianite (IV) of the Zia Formation

and occurs below the range of most Albuquerque

wells; however, this unit locally provides potable

water in Rio Rancho.

Subsurface correlation of laterally extensive strata

provides a basis for local differentiation of the Santa

Fe Group. In particular, two sequences of finegrained silty sand and clay (IX and III), first characterized in detail in a corehole drilled near the intersection of 98th Street and Interstate 40 on the West

Mesa, are traceable in the subsurface (Allen and

others, 1998). These units, provisionally named the

upper and lower Atrisco members of the middle red

formation, can be traced for several kilometers

(Connell and others, 1998). The top of the upper

Atrisco member separates coarse-grained sand and

gravel of the Sierra Ladrones Formation from underlying fine- to medium-grained silty sand and

clay of the middle red formation. This contact also

marks an important hydrogeologic boundary between highly productive strata of the USF (I-III) and

less-productive aquifers of the MSF (II, III, IX) hydrostratigraphic units. Wells that produce potable

water from the USF have specific capacity (SC) values of 66 to 75 gpm/ft and saturated hydraulic conductivity (k) values of 40 to 71 ft/day (~10-4 m/s).

In contrast, wells completed in the MSF aquifer

system yield SC values of 6 to 39 gpm/ft and k values of about 4 to 12 ft/day (~10-5 to 10-4 m/s).

Subsurface data also illustrate the influence of buried geologic structures on basin architecture in the
34

Albuquerque metropolitan area. A series of northstriking, down-to-the-west normal faults, such as

the Sandia fault zone, mark the eastern margin. The

East Heights fault zone generally marks the eastern

limit of highly transmissive deposits of the Sierra

Ladrones Fm. Eastward thickening of Sierra Ladrones strata and divergence of marker beds are

local indications of syndepositional faulting. Initial

findings also suggest that the top of the Sierra Ladrones Formation (USF) is diachronous and has migrated eastward during the Plio-Pleistocene in response to tectonic subsidence along the eastern basin margin. Such a response would have caused

early Pleistocene deposition of the highly transmissive Sierra Ladrones Formation (USF-2) beneath

much of Albuquerque.

Synthesis of surface mapping and subsurface data

shows poorly exposed faults that influence the distribution of aquifer units segment the basin. Only

through the integration of these data sets can we

recognize major structural and stratigraphic trends.

REFERENCES

Allen, B.D., Connell, S.D., and Hawley, J.W., 1998, Core drilling provides information about Santa Fe Group aquifer

beneath Albuquerque’s West Mesa: New Mexico Geology, v. 20, p. 8-13.

Bryan, K., and McCann, F.T., 1937, The Ceja del Rio Puerco--a border feature of the Basin and Range province in New

Mexico, part I, Stratigraphy and structure: Journal of Geology, v. 45, p. 801-828.

Connell, S.D., Allen, B.D., and Hawley, J.W., 1998, Subsurface stratigraphy of the Santa Fe Group from borehole geophysical logs, Albuquerque area, New Mexico: New Mexico Geology, v. 20, p. 2-7.

Hawley, J.W., 1996, Hydrogeologic framework of potential recharge areas in the Albuquerque Basin, central New Mexico, in Hawley, J.W., and Whitworth, T.M., (eds.), Hydrogeology of potential recharge areas and hydrogeochemical

modeling of proposed artificial-recharge methods in basin- and valley-fill aquifer systems, Albuquerque Basin, New

Mexico: New Mexico Bureau of Mines and Mineral Resources Open-File Report 402-D, Chapter 1.

Hawley, J.W., and Haase, C.S., (compilers), 1992, Hydrogeologic framework of the northern Albuquerque Basin: New

Mexico Bureau of Mines and Mineral Resources Open-File Report 387, variously paged.

Lucas, S.G., Williamson, T.E., and Sobus, J., 1993, Plio-Pleistocene stratigraphy, paleoecology, and mammalian biochronology, Tijeras arroyo, Albuquerque area, New Mexico: New Mexico Geology, v. 15, p. 1-8.

EXPRESSION OF FAULTS IN HIGH-RESOLUTION AEROMAGNETIC DATA

NEAR ALBUQUERQUE, NEW MEXICO—PRELIMINARY RESULTS

V.J.S. Grauch

U. S. Geological Survey, Mineral Resources Team,

Box 25046, MS 964, Denver, CO 80225

<tien@usgs.gov>

High-resolution aeromagnetic surveys were conducted in 1996 and 1997 in the Middle Rio Grande

Basin near Albuquerque, New Mexico. Maps from

these surveys show expressions of faults, volcanic

rocks, and lithologic variations within the sediments

of the Santa Fe Group aquifer system. The Tertiary

to Quaternary sediments of the aquifer system can

be divided into hydrostratigraphic units exhibiting

a wide permeability range. Thus, delineation of

faults, which may juxtapose different hydrostratigraphic units, and identification of variations

in rock types are important for understanding the

hydrogeology of the Basin. Moreover, certain fault

zones have a unique magnetic signature unrelated

to the units they juxtapose. This signature may indicate fracturing or changes in mineralogy at the

fault zones that might be hydrogeologically significant. Two faults that are known hydrologic barriers

exhibit this signature, which suggests a relation

between the magnetic signature and reduced permeability.
In 1996, aeromagnetic data were acquired along

east-west flight lines using two different specifications. The Rio Rancho survey, covering an area

north and west of Albuquerque that included Rio

Rancho and Sandia Pueblo lands, was flown at 100-

m line spacing and at 100 m height above ground

level (AGL). The Albuquerque West survey, covering the West Mesa area to Rio Puerco, was flown

using 150-m line spacing and at a height of 150 m

AGL. Exceptions to the specifications for both surveys were over urban areas where heights reached

about 300 m AGL. Tests on the results from these

surveys indicated that optimum specifications for

resolving features of interest while keeping costs

down are 150-m line spacing and 150-m AGL. The

equal ratio of line spacing to height above ground

gives proper sampling of the magnetic field so that

the observed data can be filtered to enhance the desired details. In late 1997, two contiguous surveys

were acquired using these optimum specifications:

the Kirtland-Sandia survey, covering Kirtland Airforce Base and Sandia National Laboratories; and

the Isleta survey, covering Isleta Pueblo lands and

the village of Los Lunas, south of Albuquerque.

Only preliminary data are currently available from

the 1997 surveys.

All the aeromagnetic data show expressions of numerous sinuous, generally north- to northnortheast-striking faults within the basin, as well as

expressions of exposed and shallowly buried volcanic rocks, crystalline basement at the shoulders of

the Rio Grande Rift, lithologic variations within the

Santa Fe Group, and anthropogenic structures.

Magnetic expressions due to intra-basinal faults

were identified by: (1) semi-linear magnetic expressions that have little relation to topography; (2) association with surface exposures of faults determined from discussions with geologists mapping in

the area; and (3) correspondence to general locations of faults determined from drill-hole information. Linear magnetic anomalies that have no relation to topography indicate that the anomalies have

a geologic rather than geomorphologic origin. Associations with exposed or inferred faults give the

best confidence that the magnetic features are expressions of faults. This confidence allows faults to

be delineated by the aeromagnetic data in areas

covered by widespread eolian sand. On the other

hand, not all mapped faults have magnetic expression.

Faults that offset volcanic rock are displayed as linear breaks in the highly variable magnetic expression of the volcanic rocks. Some of these breaks can

be extended as linear anomalies into neighboring

sediments. For example, the magnetic expression of

basalt related to Albuquerque volcanoes is cut by

linear breaks on both sides of the vent area, supporting the idea of a north-striking, basalt-filled

graben. The graben faults extend 10–15 km beyond

the area of basalt into alluvial areas, as expressed by

linear anomalies. The western fault extends to the

north and the eastern one to the south.

Magnetic anomalies associated with intrasedimentary faults are linear with amplitudes

ranging from 2 to 10 nanoTesla. Two types of signatures can be recognized: (1) paired highs and

lows, and (2) a low flanked by highs on either side.

The first signature is most likely caused by significant offsets between different units within the Santa

Fe Group. From preliminary models, significant

offsets can be on the order of a hundred meters or

more. In addition, magnetic material can be juxtaposed against less magnetic material on either the

down-thrown or up-thrown side of the fault.

The second type of magnetic signature is produced

by lower values of magnetization within a zone encompassing the fault. From preliminary models, the

zone is generally about 250–300 m wide. The lower

values could be caused by brecciation, chemical

changes due to circulating fluids, a lithologic difference originating from fault-controlled sedimentation, or some combination of these factors. The signature is easiest to recognize from horizontalgradient enhancements of the magnetic data, which

indicate that faults with this signature are widespread. Segments of the Hubbell Springs and Cat

Mesa faults exhibit this signature in preliminary

aeromagnetic data south of Albuquerque. Both

faults are considered hydrologic barriers and can be

used to bound hydrologic models of the basin on

the west (Cat Mesa) and east (Hubbell Springs)

sides. The correspondence suggests that the

mechanism that reduces magnetization along the

fault zone also reduces permeability. Further work

is required, however, to understand the mechanism

and to establish this relation.
PRELIMINARY GEOPHYSICAL RESULTS

FROM THE RIO RANCHO AREA, NEW MEXICO

Maria Deszcz-Pan1, Brian Rodriguez1, V.J.S. Grauch1,

Byron D. Stone2

, David A. Sawyer3, and Victor Labson1

1

U.S. Geological Survey, Mineral Resources, MS 964,

Box 25046, Denver, CO 80225 2

U.S. Geological Survey, National Cooperative Geologic Mapping,

101 Pitkin St., East Hartford, CT 06108 3

U.S. Geological Survey, National Cooperative Geologic Mapping, MS 913,

Box 25046, Denver, CO 80225

<maryla@usgs.gov>

A combined airborne time-domain electromagnetic

pulse (TDEM) and magnetic survey was conducted

in March 1997 in the Rio Rancho area, New Mexico.

The survey area generally coincides with a highresolution magnetic survey conducted in 1996 (see

Grauch et al., this volume). In addition to the airborne surveys, ground electrical resistivity (DC) and

audiomagnetotelluric (AMT) studies were performed in the summer of 1997. The primary objective of the geophysical surveys was to delineate

geological structures and facies changes within the

Santa Fe Group aquifer system that are important to

the local and regional hydrogeology. The surveys

were based on the assumption that the axial-channel

gravel deposits, which are the main aquifers in the

Middle Rio Grande Basin, will have a higher electrical resistivity than surrounding finer-grained materials.

Several factors dictated the decision to use the airborne TDEM method for this investigation. First,

airborne methods efficiently provide significant

amounts of information over a wide area. Second,

airborne TDEM can be used to infer the general

distribution of the electrical resistivity up to a depth

of several hundred meters from the surface—a

greater depth penetration than available from other

airborne electromagnetic (EM) methods. Even

though the method has been used for many years as

a geophysical prospecting tool to find massive sulfides, its use in hydrogeological mapping is new.

Therefore, interpretative techniques to map the

subtle resistivity variations due to facies changes are

not yet fully developed.

The GEOTEM TDEM system (operated by Geoterrex) sends and receives EM signals, and the recorded voltages are converted to resistivity. An

antenna mounted on the airplane generates a burst

of EM signal in the GEOTEM TDEM system. In the

receiver, the arriving EM signal is recorded as a

voltage at specific times after each pulse (TDEM

response). The received signal is affected by many

factors, but, ideally, the shape and strength of the

signal depends on the resistivity distribution in the

subsurface. Therefore, using appropriate algorithms, the measured voltages can be converted to

the electrical resistivity distribution with depth. In

general, a stronger signal indicates lower resistivity

and a weaker signal indicates higher resistivity.

Earlier arrival times provide information on the

shallower depths, and later arrival times provide

information on the deeper depths.

The Rio Rancho survey covered a 25 km x 40 km

area. It was flown using 400-m flight spacing at 120

m above ground level (AGL). Over urban areas, the

flight height reached about 250 m AGL. A data

point was recorded every 30 m along the flight direction.

Cultural features affect the response of the TDEM

system. Fences, pipelines, communication lines,

railways and other man-made conductors can contaminate the responses. The areas affected by such

cultural noise can not be used for interpretation.

The majority of cultural anomalies can be easily

identified, but sometimes the cultural noise response is very subtle and can be mistaken for the

earth response. Cultural noise severely affects the

Rio Rancho area, especially in the central and eastern part of the survey.

In order to obtain resistivity information in areas

affected by cultural noise and to provide an independent check on the interpretation of TDEM models, we collected ground-based DC and AMT data in

the study area. Preliminary resistivity values interpreted at a few points from AMT, DC and TDEM

models are in the range of 100 to 5 ohm-m, which is

also a resistivity range measured by induction logs

in wells scattered over the area.
Our preliminary results, in the form of maps of

voltages recorded at different times, show a good

agreement between the TDEM response and other

subsurface information. Clear changes in the TDEM

response occur at several mapped faults and at

faults inferred from the high-resolution magnetic

survey. Voltage maps for most times show a similar

geographic pattern that can be divided into five areas of distinct voltage responses. On the east, we

observe a very low voltage area that can be related

to thick axial-gravel deposits of the Ancestral Rio

Grande inferred from well logs. The western

boundary of this low voltage area is roughly 2 km

east of the inferred western boundary of the thick

axial-river deposits. To the northwest, an area of

higher voltages coincides with the Zia Horst, in

which uplifted silty units of the lowest Santa Fe

Group deposits are near the surface. To the south of

the Zia Horst, at the center of the map, lower voltages correspond in part to channel-rich middle

Santa Fe units. The voltage pattern suggests this

unit does not extend as far north as expected. On

the other hand, exposed basalt in the southern part

of this area, which is prominent on the magnetic

map, is not observed on the voltage maps. Either

the basalt is too thin to be detected or its electrical

properties are similar to the underlying deposits.

On the west, the Mesozoic Mancos shale likely

causes the highest voltages; the eastern boundary of

this area coincides with the Sandhill Fault. Between

the highest voltages on the west and the lower voltages in the center of the map is an area of moderate

voltages, which is bounded on the east by two faults

clearly observed on the magnetic data.

We need to determine the electrical resistivity values that correspond to particular geological units.

We had hoped to use the contractor-provided electrical conductivity-depth-thickness (CDT) profiles to

identify the zones of different resistivity, but preliminary comparison of the profiles with induction

logs was disappointing in the Rio Rancho area (in

the Cochiti area, the few logs and AMT models

roughly agreed). Another algorithm, developed

and owned by BHP geophysical company, provided

resistivity sections that closely correlated with well

logs and available geological sections. We need to

develop an algorithm that will invert the data to

reliable resistivity-depth information.

ELECTROMAGNETIC SURVEYS IN THE RIO GRANDE FLOODPLAIN,

MIDDLE RIO GRANDE BASIN, NEW MEXICO—SECOND-YEAR STATUS

Joseph M. Sterling1 and James R. Bartolino2

1

New Mexico Institute of Mining and Technology, Socorro, NM 87801 2

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

Quantifying the hydraulic linkage of the Rio Grande

to the Santa Fe Group aquifer system is of prime

importance in managing the water resources in the

Middle Rio Grande Basin. The river and aquifer are

linked through the approximately 25-meter (m)-

thick sequence of inner-valley alluvium underlying

the Rio Grande flood plain. These alluvial deposits,

which contain sediments ranging from cobbles to

clay, are a major factor controlling the volume of

water that can move between the Rio Grande and

the aquifer system. In the ground-water-flow

model of Kernodle and others (1995) vertical hydraulic-conductivity values for the inner-valley alluvium were assumed to range from 12.2 meters per

day (m/day) for most of the inner-valley alluvium

to 0.15 m/day for an area of silty clay. Silty-clay

layers exist within much of the inner-valley alluvium; although many of these layers are discontinuous, they are as thick as 4 to 6 m locally. Information on the distribution and geometry of siltyclay layers in the inner-valley alluvium is essential

for quantifying the amount of water transmitted

between the Rio Grande and the Santa Fe Group

aquifer system. This article describes the preliminary results of the second phase of a study evaluating the use of electromagnetic surveys to provide

this information. Woodward (1997) described results of the first phase.
The second phase of this study was conducted in

the spring and summer of 1997 to determine the

distribution and geometry of significant silty-clay

layers buried in the inner-valley alluvium. Surveys

were conducted using a ground-transient electromagnetic system: the Geonics EM-34 (frequency

domain). (The use of firm, trade, and brand names

in this report is for identification purposes only and

does not constitute endorsement by the U.S. Geological Survey.) During the second phase, 31 EM-34

sections ranging from 80 to 1,600 m long were located in the Rio Grande floodplain between

Alameda and Rio Bravo Boulevards (Fig. 6). Stations were spaced 20 m apart in each section, and

both horizontal- and vertical-dipole measurements

were collected at three intercoil separation distances

(5, 10, and 20 m).

For preliminary interpretation, sections with terrain-conductivity values larger than 40 millimhos

per meter (mmhos/m) were assumed to contain

detectable amounts of silty clay because of correlation with lithologic logs. In addition, sections that

had stations that had widely contrasting terrainconductivity values (>10 mmhos/m) for different

intercoil spacings probably contain detectable

amounts of silty clay because of the inhomogeneity

of the measurements. By using these criteria, all or

parts of 14 of the 31 survey lines are probably underlain by silty-clay layers. Specific conductance of

the ground water was assumed to have a uniform

effect on terrain-conductivity values; Bexfield and

Anderholm (1997) measured specific conductance

ranging from 280 to 1,771 microsiemens per centimeter at 25o Celsius in water from 14 wells in the

Rio Grande floodplain in the Middle Rio Grande

Basin. Topographic effects were not considered for

these preliminary interpretations.

Terrain-conductivity values for two survey lines

show differences (Fig. 7); one section represents terrain-conductivity values for alluvium without siltyclay layers, and the second section represents terrain-conductivity values for alluvium with silty-clay

layers. The I40S1 survey line was on the east side of

the Rio Grande, began approximately 200 m south
of Interstate Highway 40, and was 720 m long (Fig.

6). The RBRN2 survey line also was on the east side

of the river, began approximately 1 km north of Rio

Bravo Boulevard, and was 1,600 m long (Fig. 6).

Table 2 summarizes the range, variability, and interpretation of terrain-conductivity values for the

two sections shown in Figure 7. In section I40S1, the

low terrain-conductivity values (<40 mmhos/m)

and the small variability of terrain-conductivity

values (<10 mmhos/m) at each station strongly inFigure 7. Terrain conductivity along the I40S1 and RBRN2 sections. Note the similarity of conductivity values in the

I40S1 section and the contrasts between conductivity values for different spacings in the RBRN2 section.
Table 2. Summary of range, variability, and interpretation of terrain-conductivity values for sections I40S1

and RBRN2.

Variability of terrain

conductivity values at

Section each station (mmhos/m) Stations

(m)

Range of terrainconductivity

values

(mmhos/m)

Vertical

dipole

Horizontal

dipole

Interpretation

I40S1 All 10-29 <10 <4 Alluvium without silty-clay layers

0-440 10-55 10-40 10-20 Alluvium with strong indication of

silty-clay layers

460-760 10-55 10-40 <10 Alluvium with likely indication of

silty-clay layers

780-940 10-55 10-40 10-20 Alluvium with strong indication of

silty-clay layers

RBRN2

960-1,600 10-55 10-40 <10 Alluvium with likely indication of

silty-clay layers

dicate a lack of silty-clay layers in the alluvium

throughout this section. In section RBRN2, the high

terrain-conductivity values likely indicate silty-clay

layers within the alluvium throughout the section;

the large variability of terrain-conductivity values at

stations 0 to 440 m and 780 to 940 m strongly indicates silty-clay layers within the alluvium at these

stations.

Terrain-conductivity data collected at each station

for the three intercoil separation distances at each

dipole orientation are currently (1997) being entered

into the EMIX 34 Plus computer program (Interpex

Limited, 1989) to aid in interpretation. This software allows terrain-conductivity measurements to

be interpreted in terms of one-dimensional layered

earth models with as many as three plane layers at

each station to provide a probable geologic section.

Such interpretations will be checked against

lithologic and petrophysical logs from wells and

borings made near the sections. Because of substantial variations in terrain conductivity from cultural or other interferences, however, there may be

difficulties in interpretation.

This geophysical approach to delineate buried siltyclay layers is anticipated to complement work begun by personnel of the New Mexico Bureau of

Mines and Mineral Resources to map the physical

stratigraphy of the inner-valley alluvium by interpreting petrophysical and drillers’ logs.

REFERENCES

Bexfield, L.M., and Anderholm, S.K., 1997, Water-quality assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas—Ground-water quality in the Rio Grande flood plain, Cochiti Lake, New Mexico, to El Paso, Texas,

1995: U.S. Geological Survey Water-Resources Investigations Report 96-4249, 93 p.

Interpex Limited, 1989, EMIX 34 Plus software: Golden, Colorado.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114 p., 1 pl.

Woodward, D.G., 1997, Electromagnetic surveys in the Rio Grande flood plain, Middle Rio Grande Basin, New Mexico,

in Bartolino, J.R., (ed.), U.S. Geological Survey Middle Rio Grande Basin Study--Proceedings of the first annual

workshop, Denver, Colorado, November 12-14, 1996: U.S. Geological Survey Open-File Report 97-116, p. 30-31.
98th Street Core

THE 98TH STREET CORE:

KEY TO ANALYSIS OF SANTA FE GROUP STRATIGRAPHY AND HYDROGEOLOGY

IN THE CENTRAL MIDDLE RIO GRANDE BASIN

Byron D. Stone1 and Bruce D. Allen2

1

U.S. Geological Survey, National Cooperative Geologic Mapping Team,

101 Pitkin St., East Hartford, CT 06108 2

New Mexico Bureau of Mines and Mineral Resources, 2808 Central Ave., S.E., Albuquerque, NM 87106

Core samples, cuttings, and geophysical logs from

the 1560-ft (475.5-m) core hole drilled at 98th Street

on the west side of Albuquerque provide key stratigraphic and hydraulic-property information for the

upper clastic sediments of the Santa Fe Group. The

Santa Fe Group is an important unit because the

sediments form the principal aquifer in the region.

These core samples (751.5 ft, 229 m) are the only

undisturbed samples of non-lithified and lithified

sediments of the upper part of the Santa Fe Group

that have been collected in this area. The samples

have allowed us to characterize the lithic and sedimentologic features of this part of the section, and

to correlate the geology with geophysical-log characteristics, magnetic susceptibility measurements,

hydraulic variables, and trace-element geochemistry. This report chiefly addresses the stratigraphic

and lithologic features determined from the 98th

Street core hole; Hudson and others (this volume)

address paleomagnetic and rock magnetic studies.

The U.S. Geological Survey and the City of Albuquerque cooperatively drilled the core hole and an

adjacent water-level monitoring well. The New

Mexico Bureau of Mines and Mineral Resources and

the New Mexico Office of the State Engineer collaborated in the investigation to improve understanding of aquifer characteristics and controls on

ground-water availability and quality.

Three informal lithostratigraphic units summarize

the present stratigraphic framework for the 98th

Street site (Fig. 8). The top unit, 0–19 ft depth, consists of Quaternary eolian sand and valley-border

alluvium. Underlying coarse-grained deposits, 19–

97 ft depth, are correlated with the upper unit of the

Santa Fe Group (USF, Fig. 8; equivalent to the Ceja

Member of the Santa Fe Formation of Kelly, 1977,

and correlated with the Sierra Ladrones Formation

of Machette, 1978). Gravel-clast composition indicates a northwestern source for this unit; basal pebble-cobble gravel disconformably overlies finer

grained beds.

The sequence of interbedded sand, silty sand, silty

clay, and clay from 97 ft to 1560 ft is correlated tentatively with the middle unit of the Santa Fe Group

(equivalent to the upper part of the Middle Red

Member of Kelly, 1977). Allen and others (1998)

and Connell and others (1998), however, correlate

the sandy interval between 97 ft and 441 ft with the

lower part of the Sierra Ladrones Formation (included in the upper Santa Fe hydrostratigraphic

unit of Hawley and others, 1995). Connell and others (1998) correlate the 441–787 ft interval with the

extensive Atrisco Member (informal) of Connell and

others (1998). It consists of thin-bedded fine sand,

poorly sorted silty sand, and laminated silt, fine

sand, and clay. Core samples and geophysical logs

demonstrate that this interval is finer-grained than

overlying and underlying beds. The interval contains numerous and relatively thick sequences of

red (2.5YR 4/6; Munsell, 1975) to reddish brown

(2.5–5YR 5/4) clay, and silt in sets of laminated beds

commonly <2 ft (0.61 m) thick, but as much as 4.45

ft (1.36 m) thick. A distinctive olive-colored zone

between 709 ft and 756 ft consists of light-olive

brown (2.5Y 5/2–4) to dark-grayish brown (2.5Y

4/2) silty clay, and silty fine to medium sand.

A series of laterally extensive, fluvial overbank deposits makes up the entire upper part of the middle

Santa Fe unit (97–787 ft). Such deposits probably

accumulated in shallow abandoned channels or

backswamp ponds, the extent of which may have

been related to syndepositional faults that controlled the location of the main river channel, tributary channels, and overbank flats (Fig. 9). A playalake origin for these fine-grained beds is inconsistent with the evidence; no evaporite minerals,
desiccated mud-flat polygons, eolian concentration

of dried clay pellets, deltaic foreset strata, rippledrift cross laminations, or wave segregated and

sorted sediment in wavy bedforms were observed.

The lower section of the middle Santa Fe unit, 787–

1500 ft depth, includes an upper and a lower seFigure 8. Stratigraphic framework of the 98th Street core-hole site. WT, water table; Q, Quaternary period; USF, upper unit

of the Santa Fe Group; MSF, middle unit of the Santa Fe Group; MSF Atrisco M., the Atrisco Member of the middle unit of

the Santa Fe Group; VA, valley-border alluvial unit.
quence. The upper sequence consists of moderately

sorted, channel-fill medium sand, derived from

northeastern and northern fluvial source areas, and

the lower sequence consists of sand and interbedded silt and clay overbank deposits.

We base the age of the cored interval of the Santa Fe

Group on paleomagnetism and correlation to dated

sections. The fluvial gravel beds of the upper Santa

Fe unit regionally are related to establishment of an

integrated, through-flowing river system in the Rio

*UDQGH ULIWV\VWHPLQ(DUO\ 3OLRFHQH WLPH 0D

(Lozinsky and others, 1991; Chapin and Cather,

1994). We use regional correlation and preliminary

paleomagnetic data to estimate the age of the middle Santa Fe Group. At Loma Colorado, 13.7 mi. (22

km) north-northeast of the 98th Street site, sandy

light-brown and reddish-brown beds that directly

underlie gravel deposits of the upper Santa Fe unit

(S.F. Personius, USGS, pers. communication, 1997)

reportedly are of Late Miocene (Hemphillian) age

(R.H. Tedford, pers. communication, 1997), 4.6–8.9

Ma (Woodburne and Swisher, 1995). Paleomagnetic

data from the 98th Street core (Hudson and others,

1998) indicate that the middle Santa Fe unit, below

97 ft, is dominantly normal magnetic polarity. This

section may correlate with closely-spaced normal

magnetic chrons, 5.9–8.3 Ma in age (chrons

C3An.1n-C4r.1n; Berggren and others, 1995), or

with older normal chrons. The entire cored interval

may span only a few million years.

We identified 22 lithologic units in the cored interval based on detailed examination of core samples

and geophysical logs (Fig. 8). Beds with similar

grain size, sedimentary structure, and composition

characterize the lithologic units. We relate

lithologic units to genetic lithofacies of the Middle

Rio Grande Basin established by Hawley and others

(1995; and Hawley, 1996). The lithofacies have

characteristic geophysical-log signatures and lithic

parameters that affect ground-water production

(Fig. 10; Haase and Lozinsky, 1992; Connell and

others, 1998).

In the 98th Street area, the upper Santa Fe Group

beds represent basin-floor fluvial lithofacies comprising sand and gravel (lithofacies I), and alluvial

channel-fill sand facies, consisting of sand with

lenses of pebbly sand, silt, and silty clay (lithofacies

II). The upper part of the middle Santa Fe Group

contains interbedded sand, silt, and silty clay (modified lithofacies III, IV, IX) that were presumably deposited in overbank environments. Alluvial channel-fill sand facies with thin zones of overbank deposits compose the lower part of the middle Santa

Fe unit. We summarize characteristics of three of

these prominent lithofacies below.

Lithofacies III: Basin-floor alluvial, local lacustrine, and

eolian interbedded sand, silt, silty clay (unit 16, 237–336

ft depth). Unit consists of interbedded thin beds of

clayey and sandy silt, silty fine sand, brown (7.5YR

5/4) silty clay, red (2.5YR 4/6) to reddish brown

(2.5–5YR 5/4) clay, and scattered beds of medium

sand. Gamma and conductivity logs are characterized by highly variable baselines with prominent

spikes that are related to clay beds and to interbedded sequences of silt, clay, and sorted fine sand. In

these logs, clay beds >0.2 ft (6 cm) thick are characterized by narrow-single, or broad-compound, highamplitude spikes. Thick clay beds, >1 ft (30 cm)

thick in the 237–264 ft-depth interval, are characteristically red to reddish brown, medium to high

plasticity, massive to indistinctly microlaminated.

Density of clay beds, and sandy silt and sand beds is

similar (2.12–2.25 g/cc). Porosity, however, is

greater for clay beds (>45%) than for sandy silt and

sand beds (30–40%). Depositional environments

probably were fluvial inter-channel overbank areas,

Figure 9. Depositional environments for three prominent lithofacies in a faulted alluvial-plain setting.
small secondary stream channels, and ponded areas.

Lithofacies II: Basin-floor fluvial sand, lenses of pebbly

sand, silt, and silty clay (unit 8, 787–1017 ft depth).

Unit consists of gray (10YR 6/3–4/4) to light brown

(7.5YR 6–5/4), fine to medium, moderately to

poorly sorted sand and silty sand with coarse sand

layers, scattered granules, and pebbles. Framework

pebble gravel was recovered near 825-, 833-, 843-,

and 860-ft depths. Thin silty clay and clay interbeds, <1 ft (30 cm) thick, were sampled in the 850–

880-ft depth interval and near 978 ft. In gamma and

conductivity logs, baselines of low values and low

variability characterize medium sand. Deflections

in gamma, conductivity, and porosity logs show

vertical variability in 2–4-ft (0.6–1.2 m) lengths,

which are related to interbedded sequences of silt,

clay, and sorted fine sand beds within the sand.

Scattered, thin clay beds, >0.2 ft (6 cm) thick, produce sharp, high-amplitude spikes. Thin, silty clay

beds produce low-amplitude spikes in both logs.

Density values of 2.05–2.20 g/cc and porosity values

of 30–35 percent are typical for medium sand. Density values >2.25 g/cc, along with low porosity values, are related to thin beds of sandstone. Likely

depositional environments include fluvial secondary stream channels and overbank areas.

Lithofacies IX: Basin-floor alluvial flat and local lacustrine silty clay interbedded with silty sand, silty clay, and

clay (unit 12, 534–630 ft depth). Unit consists of

reddish-brown to brown (5–7.5YR 5/4–4/6) clay

and silty clay with interbedded fine to medium silty

sand. Clay beds are massive to indistinctly microlaminated, locally preserving delicate laminae of

clay and silt. In gamma and conductivity logs, a

Figure 10. Lithology and geophysical logs for three prominent lithofacies of the 98th Street core.
variable baseline distributed around relatively high

values characterizes the silty clay sequence. Deflections in gamma, conductivity, and porosity logs

show vertical variability in 2–4 ft (0.6–1.2 m)

lengths, which are related to interbedded sequences

of silt and fine sand beds within the clay. Ten-ft- (3-

m-) thick zones of clay, composed of beds >0.2-ft (6-

cm) thick, produce broad, high-amplitude compound spikes in both gamma and conductivity logs.

Thin clay beds, or silty clay beds produce numerous

low-amplitude spikes in both logs. Density values

of 2.12–2.25 g/cc and porosity values of >45 percent

are typical for silty clay and clay. Extensive, fluvial

overbank areas and secondary stream channels are

the presumed depositional environments.

We summarize the hydrogeologic framework for

the 98th Street site using four hydrostratigraphic

units that closely relate to the lithostratigraphic

units and their included lithofacies (Fig. 8). Estimated average horizontal hydraulic conductivity

(K) values for lithologic units in the 98th Street core

hole were derived from the empirical relationships

of permeability and grain size of non-cemented

samples of the Santa Fe Group (Detmer, 1995). We

estimate the ranges of values (in parentheses, Fig. 8)

from the variability of data points in the original

analysis (Fig. 3 in Detmer, 1995). We base the estimated K values for hydrostratigraphic units on K

values of the included lithologic units, normalized

to their proportional thickness in the hydrostratigraphic units. The empirical K values estimated

from core samples reveal a previously unidentified

contrast in hydraulic conductivity in the lowest-two

hydrostratigraphic units. Correlating among

nearby wells shows that the fine-grained deposits of

the Atrisco Member of the middle Santa Fe unit extend throughout much of the Albuquerque metropolitan area. With an estimated hydraulic conductivity of <0.02–17 ft/day, the Atrisco Member acts as

a laterally extensive barrier to vertical ground-water

flow, separating the upper Santa Fe Group aquifer

from the middle Santa Fe aquifer. The underlying

unit comprises thick sequences of moderately sorted

medium sand and is therefore a potential production zone of the aquifer that bears further investigation.

REFERENCES

Allen, B.D., Connell, S.D., Hawley, J.W., and Stone, B.D., 1998, Core drilling provides information about Santa Fe

Group aquifer beneath Albuquerque’s west side: New Mexico Geology, v. 20, p. 8-13.

Berggren, W.A., Kent, D.V., Swisher, C.C., III, and Aubrey, M.P., 1995, A revised Cenozoic geochronology and chronostratigraphy: Society for Sedimentary Geology (SEPM) Special Publication No. 54, p. 130-212.

Chapin, C.E., and Cather, S.M., 1994, Tectonic setting of the axial basins of the northern and central Rio Grande Basin,

New Mexico, in G.R. Keller and S.M. Cather (eds.), Basins of the Rio Grande Rift—Structure, stratigraphy, and

tectonic setting: Geological Society of America Special Paper 291, p. 5-25.

Connell, S.D., Allen, B.D., and Hawley, J.W., 1998, Subsurface stratigraphy of the Santa Fe Group from borehole geophysical logs, Albuquerque area, New Mexico: New Mexico Geology, v. 20, p. 2-7.

Detmer, D.M., 1995, Permeability, porosity, and grain-size distribution of selected Pliocene and Quaternary sediments in

the Albuquerque Basin: New Mexico Geology, v. 17, p. 79-87.

Haase, C.S., and Lozinsky, R.P., 1992, Estimation of hydrologic parameters, in J.W. Hawley and C.S. Haase (compilers), Hydrogeologic framework of the northern Albuquerque basin: New Mexico Bureau of Mines and Mineral Resources, Open-File Report 387, p. VI-1-VI-3.

Haneberg, W.C., Gomez, P., Gibson, A., and Allred, B., 1998, Preliminary measurements of stress-dependent hydraulic

conductivity of Santa Fe Group aquifer system sediments from the 98th Street core hole, Albuquerque, New Mexico: New Mexico Geology, v. 20, p. 14-20.

Hawley, J.W., 1996, Hydrologic framework of potential recharge areas in the Albuquerque basin, central New Mexico,

in J.W. Hawley and T.M. Whitworth (eds.), Hydrology of potential recharge areas and hydrogeochemical modeling

of proposed artificial-recharge methods in basin- and valley-fill aquifer systems, Albuquerque Basin New Mexico:

New Mexico Bureau of Mines and Mineral Resources Open-File Report 402-D, Chapter 1, p. 1-71.

Hawley, J.W., Haase, C.S., and Lozinsky, R.P., 1995, Hydrogeologic framework of the northern Albuquerque Basin, in

Ortega-Klett (ed.), The water future of Albuquerque and Middle Rio Grande Basin: New Mexico Water Resources

Research Institute, Technical Report No. 290, p. 37-55.

Hudson, Mark, Mikolas, Marlo, Allen, B.D., and Geissman, J.W., 1998, Paleomagnetic and rock magnetic studies of the

upper Santa Fe Group; goals and preliminary results, in J.L. Slate (ed.), U.S. Geological Survey Middle Rio Grande

Basin Study—Proceedings of the second annual workshop, Albuquerque, New Mexico, February 10-11, 1998: U.S.

Geological Survey Open-File Report 98-337.
Kelley, V.C., 1977, Geology of Albuquerque basin, New Mexico: New Mexico Bureau of Mines and Mineral Resources

Memoir 33, 60 p.

Lozinsky, R.P., Hawley, J.W., and Love, D.W., 1991, Geologic overview and Pliocene-Quaternary history of the Albuquerque Basin: New Mexico Bureau of Mines and Mineral Resources, Bulletin 137, p. 157-162.

Machette, M.N., 1978, Geologic map of the San Acacia quadrangle: U.S. Geological Survey Geologic Quadrangle Map

GQ-1415, scale 1:24,000.

Munsell, 1975, Soil Color Charts: Munsell, Inc., Baltimore, MD, 22 p.

Woodburne, M.O., and Swisher, C.C., III, 1995, Land mammal high-resolution geochronology, intercontinental overland

dispersals, sea level, climate, and vicariance: Society for Sedimentary Geology (SEPM) Special Publication No. 54,

p. 335-364.

PALEOMAGNETIC AND ROCK MAGNETIC STUDIES

OF THE UPPER SANTA FE GROUP:

GOALS AND PRELIMINARY RESULTS

M.R. Hudson1, Marlo Mikolas2, B.D. Allen3, and J.W. Geissman2

1

U.S. Geological Survey, National Cooperative Geologic Mapping Team,

Box 25046, MS 913, Denver, CO 80225 2

Dept. Earth and Planetary Sciences, Univ. of New Mexico, Albuquerque, NM 87131 3

New Mexico Bureau of Mines and Mineral Resources,

2808 Central Ave., S.E., Albuquerque, NM 87106

Paleomagnetic and rock magnetic studies of the upper part of the rift-filling Santa Fe Group within the

Albuquerque Basin were initiated in the fall of 1996

with two principal goals: (1) to provide magnetostratigraphic information on the age and duration

of sedimentation for key stratigraphic sections; and

(2) to constrain the role of Santa Fe Group sediments as a magnetic source for aeromagnetic

anomalies. Initial study has concentrated on samples collected over the 457-m depth of the 98th St.

Core from the west side of Albuquerque. A 33-mthick surface section near Belen provides further

information.

In magnetostratigraphy, we correlate normal and

reverse magnetic-polarity zones within the stratigraphic interval to a geomagnetic polarity time scale

(GPTS) to determine age. For the 98th St. Core,

about 200 samples distributed throughout the core

length have been subjected to alternating-field demagnetization to identify magnetic components and

to determine their polarity. A magnetic mineral

having moderate coercivity, probably magnetite,

carries the principal component of magnetization

throughout the 98th St. Core interval, despite a red

coloration and the presence of a high-coercivity

hematite component in some intervals. The magnetite component is dominantly of normal polarity,

but samples with reverse polarity cluster at different

depths throughout the section. We identified nine

alternating normal- and reverse-polarity zones, defined by at least two samples of consecutive polarity, within the core. Assuming that the magnetite

component was acquired at deposition, comparison

of the multiple-polarity intervals to the GPTS suggests that deposition for the core interval spans at

least 1 m.y. and probably 2–3 m.y. Nonetheless,

further work on samples from additional depths

and a more complete assessment of magnetic mineralogy and the mechanisms of remanence acquisition are needed before an exact correlation to the

GPTS can be confidently proposed.

Numerous linear anomalies identified in recent

high-resolution aeromagnetic surveys of the Albuquerque Basin are probably related to offset or alteration along faults within the Santa Fe Group

(Grauch, this volume). Variation of magnetic properties with lithology within the Santa Fe Group

gives insight into potential contrasts of total magnetization that controls the aeromagnetic expression

of these rocks. Total magnetization of rocks is the

vector sum of their induced magnetization, the

product of the magnetic field and magnetic susceptibility (MS), and their natural remanent magnetization (NRM). Within the 98th St. Core, MS varies
over three orders of magnitude, both in logs of

whole-core MS (8.3 x 10-2 to 1.1 x10-4 SI) and in individual samples extracted from the core (2.7 x 10-2 to

3.1 x 10-5 SI). MS generally correlates with grain size

such that the coarsest grained rocks have highest

MS values. A similar variation of MS versus grain

size is observed in the surface section near Belen

where axial-facies conglomerates have ten-fold

greater MS values (1.7 x 10-3 SI) than claystone horizons (2.0 x 10-4 SI). NRM values in both sections

show similar yet less pronounced correlation with

grain size. Calculations of total magnetization from

the NRM and MS values illustrate that induced

magnetization predominates over remanent magnetization in all but the finest and least magnetic of

Santa Fe Group sediments. These data suggest that

coarse-grained aquifer rocks have highest total

magnetization and thus greatest potential for generation of aeromagnetic anomalies where juxtaposed with fine sediments or where altered by fluids channeled along faults.

REFERENCES

Grauch, V.J.S., 1998, Expression of faults in high-resolution aeromagnetic data near Albuquerque, New Mexico—preliminary results, in Slate, J.L., (ed.), U.S. Geological Survey Middle Rio Grande Basin Study—Proceedings of the

second annual workshop, Albuquerque, New Mexico, February 10-12, 1998: U.S. Geological Survey Open-File

Report 98-337.

SEDIMENT AND GROUND-WATER GEOCHEMISTRY

OF THE 98TH ST. DRILL CORE

NEAR ALBUQUERQUE, NEW MEXICO

Mark R. Stanton, David J. Grimes, Richard F. Sanzolone, and Steven S. Sutley

U. S. Geological Survey, Mineral Resources Team,

Box 25046, MS 964, Denver, CO 80225

Most major elements and trace metals exhibit similar abundance patterns with depth and within a

given lithologic unit in samples from the 98th St.

drill core on the west side of Albuquerque. The

greatest amount of most trace metals, in particular

arsenic (As) and iron (Fe), is associated with finergrained materials (fine sand, silt, and clay). We

used ICP-AES (inductively coupled plasma – atomic

emission spectrometry) and ICP-MS (inductively

coupled plasma – mass spectrometry) to analyze

sediment samples.

Bulk-sample X-ray diffraction (XRD) methods have

identified: (1) major amounts of quartz; (2) varying

amounts of orthoclase, albite, and sanidine, and

other aluminosilicates, such as muscovite; (3) carbonates including major calcite and minor dolomite;

and (4) only remnants of sulfides (possibly pyrite).

We also used XRD to examine 15 clay separates; the

dominant clay minerals include illite, smectite,

mixed-layer illite/smectite, and kaolinite. Scanning-electron microscope (SEM) analyses of high

As-bearing sediments (>10 parts per million [ppm])

indicate that increased amounts of As are generally

associated with increased levels of Fe (primarily as

Fe-oxides). Arsenic concentrations in discrete core

samples taken at 1-ft intervals from 655–765 ft range

from 2 to 25 ppm on a dry-weight basis. Arsenic is

at least twice its crustal abundance value (1.8 ppm)

in 47 of the 60 discrete samples. Iron in these high

As-bearing samples ranges from 3–4 wt. percent; in

lower-As samples (≤10 ppm), Fe is 2.5 wt. percent or

less.

Concentrations of total dissolved arsenic (Astot) in

ground-water samples are as follows:

Depth

(ft)

Astot

μg/L

(ppb)

Dominant As Species

438 16 As5+ (≥90% of Astot)

749 7 As3+ (≥66% of Astot)

1112 30 As3+ (≥66% of Astot)

1544 34 As5+ (≥90% of Astot)
The two-highest solid-phase As concentrations (23

ppm at 723 ft, and 25 ppm at 759 ft) bracket the 749-

ft ground-water sample; yet aqueous Astot in the

749-ft interval is the lowest (7 μg/L) of the four

ground waters sampled. The low Astot concentration in the aqueous sample suggests As is less readily solubilized from these two dominantly fine-sand

sediments. That is, although most arsenic is present

as “mobile” As3+, the total aqueous arsenic concentration is low relative to solid-phase arsenic that is

potentially available for dissolution. The two, high

As-bearing sediments, however, may not be hydraulically connected with the ground water that

was sampled. The short screened interval (5 feet,

from 739–744 ft) may inhibit ground water input

from the high-As sediments, especially if impermeable layers are present above or below the screened

interval.

In contrast to the fine-grained sand, mediumgrained sand with relatively low solid-phase As (≤4

ppm) bracket the 1112-ft ground-water sample, but

this sample has the second-highest aqueous Astot

concentration (30 μg/L). The screened interval is

from 1102–1107 ft, and As3+ is again dominant in the

ground water. In the other two groundwater samples, As5+ is the dominant dissolved As species.

These contrasts in Astot concentrations from solidphase and aqueous samples suggest that As is more

readily solubilized from dominantly medium-sand

sediments than from dominantly fine-sand sediments.

The results also illustrate that As solubility is variable within different sample intervals. Because arsenic solubility is generally enhanced as pH increases above 7.0, the variable proportions of As3+

and As5+ from waters having high pH (8.4–9.9) suggest that local redox conditions exert strong control

on As mobility in ground water. We speculate that

the strong association of Fe and As in high-As

sediments is the result of As complexation and adsorption on Fe-oxides or Fe-oxide coatings on mineral surfaces.

Further work includes partial extraction methods

and additional SEM analyses to determine the mineral residences of arsenic in the core samples. Geochemical modeling is also underway to further define the impact of local ground-water chemistry on

the mobility of As in the sediments.
Recharge/Infiltration & Hydraulic Characteristics

EFFECTS OF BASIN-MARGIN STRUCTURE AND STRATIGRAPHY

ON GROUND-WATER RECHARGE IN THE PLACITAS AREA,

NORTHERN ALBUQUERQUE BASIN, NEW MEXICO

Peggy Johnson1, William LeFevre2, Andrew Campbell2, and Brian McPherson2

1

New Mexico Bureau of Mines and Mineral Resources, 801 Leroy Place, Socorro, NM 87801 2

New Mexico Institute of Mining and Technology, Socorro, NM 87801

Preliminary data from a ground-water study in

progress for Sandoval County by the New Mexico

Bureau of Mines and Mineral Resources, indicate

that faults in the Placitas area behave as both barriers to and conduits for ground-water flow into the

northern Albuquerque basin. Placitas is located on

the eastern margin of the Albuquerque Basin, at the

northern termination of the Sandia uplift, northeast

of Albuquerque. Major west-dipping, rift-margin,

normal faults, including the San Francisco-Placitas

fault zone and numerous subsidiary faults, cut

north-dipping Paleozoic and Mesozoic sedimentary

strata as they ramp below Santa Fe Group basin fill.

Ground water in this structurally and stratigraphically complex setting exists in a compartmentalized

aquifer system that is recharged through a combination of surface-water and preferential groundwater flow paths originating in the Sandia Mountains to the south. Piezometric data from private

wells, preliminary stable-isotope, ionic and traceelement data from ground and surface water, and

surface and subsurface geologic data indicate the

existence of an assortment of confined and unconfined aquifers with a wide range of water quality

and productivity, and varying degrees of hydraulic

interconnection. Piezometric data in the vicinity of

the Placitas and San Francisco faults generally indicate dramatic declines in fluid potential of 200 to

300 feet across these structures. Numerous springs

discharge on the up-gradient sides of the faults indicating that the faults attenuate ground-water flow

along most of their extent. Relatively gradual hydraulic gradients do occur across the faults at isolated locations, however, pointing to the existence

of preferential flow paths and/or recharge zones

that channel ground-water flow into the Albuquerque basin.

Stable-isotope data from ground water, surface water, and spring discharge are interpreted relative to

a local meteoric water line defined from a network

of precipitation collectors located along the north

slope of the Sandia Mountains. Variations in

ground-water stable-isotope ratios (δD of −119‰ to

−87‰ and δ18O of −15.0‰ to −11.4‰) appear to

spatially correlate to recharge signatures from precipitation and surface-water sources. Isolated regions of anomalously light stable isotope ratios

(−119 to −115‰ D and −15.0 to −13.6‰ 180), are interpreted to represent areas of paleowater in isolated portions of the Santa Fe Group aquifer.

Chemical analyses of mountain-front spring water

along the San Francisco-Placitas fault zone suggest a

common source of calcium-bicarbonate ground

water originating in the Madera Group limestone

(Pennsylvanian). Ground water from the Santa Fe

Group aquifer immediately down gradient of the

San Francisco fault is chemically similar to that of

the springs and the Madera aquifer wells. A significant change in general and trace-element chemistry

is detected in ground waters discharging from the

Mesozoic-age sediments adjacent to the Placitas

fault zone. These ground waters exhibit very high

concentrations of sodium (≤1450 ppm), sulfate

(≤3900 ppm), and dissolved solids (≤5950 ppm), and

elevated concentrations of iron (≤940 ppb), copper

(≤270 ppb), manganese (≤370 ppb), and zinc (≤110

ppb). Low concentrations of arsenic (5 to 21 ppb)

are generally characteristic of ground water discharging from both the Triassic age Agua Zarca and

lower Petrified Forest Formations, as well as certain

areas of the Santa Fe Group aquifer. These high

TDS, sodium-sulfate ground waters are interpreted

to reflect "long" residence times under semiconfined conditions in low permeability Mesozoicage sediments that are isolated from direct sources

of recharge.

Together these various data support a complex

pattern of recharge to the aquifers adjacent to and

down-gradient of the San Francisco-Placitas fault
zone. Recharge appears to be moving through the

Madera limestone and across the fault zones via

preferential pathways, and is also being redistributed into the aquifers as line sources of infiltrating

surface water originating from spring discharge and

stream flow. Neither piezometric data nor variations in ionic, trace-element, or stable-isotope

chemistry support a spring-discharge origin from

an alternate, deep-basin source of ground water that

flows vertically upward in the faults. Additional

ground-water sampling for age determination will

be undertaken to test this regional hydrogeologic

conceptual model.

TEMPERATURE PROFILES OF THE AQUIFER SYSTEM

UNDERLYING THE RIO GRANDE, MIDDLE RIO GRANDE BASIN,

NEW MEXICO—SECOND-YEAR STATUS

James R. Bartolino

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

An important gap in the understanding of the hydrology of the Middle Rio Grande Basin, central

New Mexico, is the rate at which water from the Rio

Grande recharges the Santa Fe Group aquifer system. The New Mexico State Engineer Office currently (1997) uses the methods of Glover and

Balmer (1954) to estimate the rate of recharge. Results of a numerical model of the Albuquerque Basin (Kernodle and others, 1995) indicate that the

Glover-Balmer equations overestimate the volume

of water recharged from the river during the 1901–

94 period of simulation. This article describes the

plan and second-year progress of a study whose

purpose is to determine the vertical hydraulic conductivity of the Santa Fe Group aquifer system that

underlies the Rio Grande. The U.S. Geological Survey plans to use this information in conjunction

with the Albuquerque Basin model to refine the estimates of recharge from the Rio Grande. This

study uses piezometer-core and temperature-profile

data to model the distribution of vertical hydraulic

conductivity (Lapham, 1989) underlying the Rio

Grande inner-valley alluvium.

Seven sets of nested piezometers were installed

during July and August 1996 at four sites along the

Rio Grande in the Albuquerque area (Fig. 11). In

downstream order, these sites are: (1) the Bernalillo

site, upstream from the State Highway 44 bridge in

Bernalillo (BRN01 and BRN02); (2) the Corrales site,

upstream from the Rio Rancho sewage treatment

plant in Corrales (COR01 and COR02); (3) the Paseo

del Norte site, upstream from the Paseo del Norte

bridge in Albuquerque (PDN01 and PDN02); and

(4) the Rio Bravo site, upstream from the Rio Bravo

bridge in Albuquerque (RBR01). At each of the first

three sites, one piezometer nest is located on the

bank and the other nest is on a sandbar in the river

channel. At Rio Bravo, the only nest was installed

on the bank because of the lack of accessible sandbars. Except for the sandbar nest at Bernalillo,

where two piezometers were installed at depths of

11 and 17 ft, three piezometers were installed in

each nest at depths ranging from 8 to 50 ft. All piezometers were completed in river valley alluvium of

the Santa Fe Group aquifer system. During installation, a core was collected at each nest. Daniel B.

Stephens and Associates analyzed 11 sediment

samples representing the most representative texture(s) from these cores for initial moisture content

(gravimetric and volumetric), dry-bulk density, initial wet-bulk density, and porosity.

Five times between September 1996 (the month of

anticipated warmest ground-water temperatures)

and April 1997, temperature profiles were measured

in the deepest piezometer in each nest and water

levels were measured in all piezometers. At the

same time, temperatures were logged in existing

150-ft piezometers at the Paseo del Norte and Rio

Bravo sites to confirm results of measurements collected from the shallow piezometers.

Figure 12 shows ground-water temperature profiles

for the COR02 and PDN01 piezometer nests located

on sandbars near the west riverbank. Although
temperatures were not logged continuously for an

entire year, the approximate warmest and coldest

temperatures presumably were measured.

The annual ground-water temperature fluctuations

shown in the temperature profiles for COR02 and

PDN01 are similar to other profiles measured for

this study, to preliminary modeling results, and to

profiles shown in Lapham (1989). In the plot for

COR02, the ground water appears to approach a

constant temperature near the bottom of the piezometer at approximately 35 ft. In the plot for

PDN01, however, fluctuations of approximately 2°

Celsius are indicated for the water near the bottom

of the piezometers at depths exceeding 50 ft. A deflection can be noted in all curves for PDN01 at a

depth of approximately 17 ft. This deflection may

result from a change in sediment texture, changes in

the direction of ground-water flow, or changes in

the source of ground-water recharge.

Models have been constructed of each of the seven

piezometer nests using the VS2DH model of Healy

and Ronan (1996). The models are being calibrated

with the ground-water temperature and hydraulichead data collected from the seven sets of piezometers.

REFERENCES

Glover, R.E., and Balmer, C.G., 1954, River depletion resulting from pumping a well near a river: EOS, Transactions,

American Geophysical Union, v. 35, no. 3, p. 468-470.

Figure 11. Location map of the Albuquerque area showing locations of the temperature

profile sites. BRN, Bernalillo site; COR, Corrales site; PDN, Paseo del Norte site; RBR, Rio

Bravo site.
Healy, R.W., and Ronan, A.D., 1996, Documentation of computer program VS2DH for simulation of energy transport in

variably saturated porous media—Modification of the U.S. Geological Survey’s computer program VS2DT: U.S.

Geological Survey Water-Resources Investigations Report 96-4230, 36 p.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114 p., 1 pl.

Lapham, W.W., 1989, Use of temperature profiles beneath streams to determine rates of vertical ground-water flow and

vertical hydraulic conductivity: U.S. Geological Survey Water-Supply Paper 2337, 35 p.

Figure 12. Ground-water temperature profiles drawn from data measured in Corrales piezometer COR02 and Paseo del

Norte piezometer PDN01.
USE OF SURFACE-WATER PULSES TO ESTIMATE

HYDRAULIC CHARACTERISTICS OF THE RIO GRANDE ALLUVIUM,

ALBUQUERQUE AREA, NEW MEXICO

D. Michael Roark

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

Ground water is the principle source of drinking

water in the Albuquerque area (Thorn and others,

1993, p.1). As increasing amounts of ground water

are pumped, water managers and others have

raised questions about how much the Rio Grande

recharges the surrounding aquifer. Because the

amount of recharge is directly related to the aquifer

characteristics of the surrounding alluvium (Thorn

and others, 1993, p.53), the Bureau of Reclamation

conducted a surface-water pulse study on the Rio

Grande in the Albuquerque area in May 1997 to estimate hydraulic characteristics of the Rio Grande

alluvium. The results of the study showed that a

pulse, an approximate 1-foot increase in river stage,

propagates from the river to the riverside drains,

but is not distinguishable in ground-water wells

beyond the drain (Bureau of Reclamation, 1995, p.

24). According to the Bureau of Reclamation (p. 24),

“Another round of field work and data modeling,

with better instrumentation and data-collection outcome, may prove useful to confirm these findings.”

McAda (1996, p. 48) further, suggested that, “It

would be useful to conduct a similar experiment,

using a flood pulse in the riverside drain rather than

the river. This would allow propagation of the

flood pulse to the alluvium beyond the drain.”

The U.S. Geological Survey is conducting a project

to estimate hydraulic characteristics of the alluvial

aquifer (Rio Grande alluvium) adjacent to the Rio

Grande and the associated drain near the Rio Bravo

Bridge. These characteristics will be determined

from results of short-duration and long-duration

surface-water pulses in the river and drains that

stress the ground-water system. The short-duration

surface-water pulses will consist of one engineered

pulse in the Rio Grande, several engineered pulses

in the East Riverside Drain, and any storm-derived

pulses in the river that occur during the datacollection period. An engineered pulse is a shortduration increase in river stage caused by water

released from upstream reservoirs specifically for

this study. The long-duration pulses will consist of

the normal changes in river stage during the year.

Long-duration pulses are useful because shortduration pulses might not stress the ground-water

system enough to result in measurable groundwater-level changes away from the river and riverside drain.

Lithologic logs of existing piezometers at the Rio

Bravo site were analyzed to determine the vertical

distribution of confining layers and strata. Three

new wells were installed after analysis of the logs to

ensure a complete data set for analysis (Fig. 13).

RBR2 is a three-well nest with well depths of 29, 50,

and 150 feet. RBR5 is also a three-well nest with

well depths of 35, 150, and 500 feet. Wells BOR1,

BOR2, BOR3, RBR6, RBR7, and RBR8 are all shallow

wells with a maximum depth of 15 feet. Slug tests

were performed on all wells to ensure that the wells

were in good hydraulic connection with the aquifer

and to determine hydraulic conductivity ranges for

the alluvium.

Pressure transducers were installed in all wells in

the section to measure water-level changes. Pressure transducers and recorders were installed at two

sites on the East Riverside Drain, and a

stage/discharge relation was developed for each

drain site by making streamflow measurements.

The south drain-gage was near the wells to record

drain stage; the north drain-gage was 3 miles upstream from the south drain-gage to determine the

volume of water that the drain is gaining or losing.

Streamflow data also were collected at the Rio

Bravo streamflow gage.

Data were collected at all sites for a 5-month period

(December 1996 to May 1997) to ensure adequate

data availability for several short-duration and

long-duration pulses. The 5-month time frame also

allowed sufficient time to collect background data

to determine which stresses were caused by the

flood pulse and which were caused by outside influences such as ground-water pumping.

The U.S. Geological Survey, the Bureau of Reclamation, the U.S. Army Corps of Engineers, and the City

of Albuquerque coordinated an engineered short-
duration pulse in the river in February

1997. February was selected to avoid interference from stresses such as canal

leakage, irrigation-return flow, and

evapotranspiration. Just before the beginning of the irrigation season in March,

the Middle Rio Grande Conservancy

District diverted water into the East Riverside Drain; this diversion served as a

long-duration surface-water pulse.

To determine aquifer characteristics, a

cross-sectional steady-state representation of the alluvial ground-water system

is being constructed using the crosssectional model functionality of Modflow-96 (Harbaugh and McDonald, 1996).

The layers of the model will represent the

vertical distribution of strata determined

from well logs. The aquifer-storage values determined from log analysis and the

hydraulic-conductivity values determined from slug tests will be used as the

initial conditions. Head-dependent flux

boundaries will be used to represent the

river and drains. Stresses of the surfacewater pulses will be simulated and aquifer characteristics will be determined using

a transient-state model.

REFERENCES

Bureau of Reclamation, 1995, Flood wave test and transient groundwater analysis: Middle Rio Grande Water Assessment Technical Memorandum, Albuquerque Projects Office, variously paged.

Harbaugh, A.W., and McDonald, M.G., 1996, Users documentation for Modflow-96, an update to the U.S. Geological

Survey modular finite-difference ground-water flow model: U.S. Geological Survey Open-File Report 96-485, 56 p.

McAda, D.P., 1996, Plan of study to quantify the hydrologic relations between the Rio Grande and the Sante Fe Group

aquifer system near Albuquerque, central New Mexico: U.S. Geological Survey Water-Resources Investigations

Report 96-4006, 58 p.

Thorn, C.R., McAda, D.P., and Kernodle, J.M., 1993, Geohydrologic framework and hydrologic conditions in the Albuquerque Basin, central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 93-4149, 106

p.

Figure 13. Map showing site locations, near Rio Bravo Boulevard in

Albuquerque.
Recharge—Santa Fe River, Bear Canyon, Abo Arroyo Studies

MEASUREMENTS OF TRIBUTARY, INTER-ARROYO, AND

MOUNTAIN-FRONT RECHARGE ON THE SANTA FE RIVER,

BEAR CANYON, AND ABO ARROYO, NEW MEXICO

Jim Constantz

U.S. Geological Survey, Water Resources Division, Branch of Regional Research,

345 Middlefield Road, MS 496, Menlo Park, CA 94025

Several research projects within the U.S. Geological

Survey-Water Resources Division (WRD) are using

a range of research techniques to estimate potential

recharge rates along the eastern flank of the Middle

Rio Grande Basin (MRGB). The goals of the projects

are to: (1) provide estimates of streambed infiltration and potential recharge at specific locations for

the daily to seasonal recharge period; (2) provide

long-term estimates of recharge for the decade to

century recharge period; and (3) compare recharge

results generated from different techniques with

respect to such parameters as mean values, ranges,

and uncertainties. Research was initiated in FY96,

some research will be completed in FY98, and other

research will be completed in FY99 and FY00. An

overview of the status of these research projects

follows.

John Nimmo, Branch of Regional Research (BRR),

Western Region (WR), WRD, and coworkers (in

these proceedings) are using the steady-state centrifuge method (SSCM) to estimate long-term recharge

rates at specific locations in the MRGB. Accurate

measurement of unsaturated hydraulic conductivity

(K) and soil moisture by the SSCM can indicate

long-term average recharge rates (Nimmo and others, 1994). The steps required are as follows. (1)

Obtain core samples from deep in the unsaturated

zone such that moisture fluctuations are negligible.

(2) Determine the total downward-driving force for

water. In a homogeneous medium, at depths where

moisture does not fluctuate, the flow is steady and

driven only by gravity. In a layered profile, however, the likelihood and magnitude of significant

matric-potential gradients must be evaluated with a

Darcy-based analysis. In either case, Darcy’s law

can indicate the local recharge rate if K, at the water

content existing at that depth, is known. (3) Measure K with the SSCM, which establishes a measurable steady flow of water in a centrifugal field as

great as 2000 g. This method is well suited for the

required measurements because it gives accurate K

values in the low-water-content range important at

arid and semiarid sites. Dave Stonestrom, BRR,

WR, WRD, and Fred Gebhardt, New Mexico District

(NM), WRD, collected core samples for the SSCM

near the Santa Fe River at La Bajada, in Bear Canyon, and Abo Arroyo. Angus Lewis, BRR, WR,

WRD, is currently determining K values.

Stonestrom and coworkers (in these proceedings)

collected bulk-soil samples at the same locations

where core samples were collected for the SSCM.

They are analyzing environmental tracers from

these bulk samples to delineate spatial patterns of

ground-water recharge and to estimate recharge

magnitudes. Chloride and bromide concentrations

are being determined by ion chromatography.

These constituents are chemically conservative and

can indicate local recharge, if assumptions about

sources are satisfied. Pore waters extracted by

cryodistillation are being analyzed for tritium, deuterium, and oxygen-18. Concentration peaks in the

unsaturated zone profile provide estimates of rates

of percolation and potential recharge on the decade

time scale. The use of multiple environmental tracers overly constrains recharge estimates and provides an indication of their accuracy in determining

long-term recharge in the vicinity of the sampling

location.

Carole Thomas, NM, WRD, and coworkers (in these

proceedings) established a series of stream gages on

the La Bajada reach of the Santa Fe River to estimate

streambed infiltration losses. She calculated streamflow from 15-minute stage measurements at each of

three sites over a 2.5-kilometer (km) reach to estimate streamflow differences between the gages for

FY97. Numerous seepage runs were performed in

June 1997 to accurately determine diurnal variations

in streamflow. These results were used as a basis to

estimate streambed-infiltration rates for comparison
to the streambed-temperature profile (stp) method

(Stewart and others, in these proceedings).

Amy Stewart, BRR, WR, WRD, and coworkers (in

these proceedings) have been using a variety of

thermal-tracking procedures (Constantz and Thomas, 1996, 1997; Ronan and others, 1997; Stewart

and others, 1997) to estimate streamflow-loss patterns at the La Bajada reach of the Santa Fe River, at

Bear Canyon, and in Abo Arroyo. They are investigating the stp method as a tool to estimate streambed percolation rates at each location. In addition,

temperature patterns at Bear Canyon and Abo Arroyo are analyzed to determine whether temperature alone can be an indicator of streamflows at the

site. A spatially distributed surface temperature

procedure is being tested at 8 sites in a 30-km reach

in Abo Arroyo between the USGS gaging station

and the Rio Grande. The procedure is designed to

measure the timing—that is, presence or absence,

and duration—of streamflow at specific locations

with the study reach. Streamflow hydrographs

from the gaging station will be compared to the

spatial and temporal patterns of streambed-surface

temperature to construct relations between hydrograph characteristics and the pattern of downstream

flows. This information will form the basis for a

protocol to develop estimates of potential recharge

for given hydrographs within the MRGB.

The SSCM and environmental method are designed

to estimate deep, long-term recharge rates on the

decade-to-century recharge period. The thermalpulse tracking procedures are designed to monitor

streambed infiltration distributions and short-term

potential recharge on the daily-to-seasonal recharge

period. A synthesis of this collaborative research

will provide insight into short-term fluctuations in

recharge and long-term average values for recharge

along the eastern flank of the MRGB.

REFERENCES

Constantz, J. and Thomas, C.L., 1996, The use of streambed-temperature profiles to estimate the depth, duration, and

rate of percolation beneath arroyos: Water Resources Research, v. 32, no. 12, p. 3597-3602.

Constantz, J. and Thomas, C.L., 1997, Streambed–temperature profiles as indicators of percolation characteristics beneath arroyos in the Middle Rio Grande Basin, USA: Hydrological Processes, v. 11, no. 12, p. 1621-1634.

Nimmo, J.R., Stonestrom, D.A., and Aksten, K.C., 1994, The feasibility of recharge rate measurements using the steady

state centrifuge method: Soil Science Society of America Journal, v. 58, no. 1, p. 49-56.

Ronan, A.D., Prudic, D.E., and Constantz, J., 1997, Effects of diurnal stream temperature variation on infiltration beneath an ephemeral stream: American Geophysical Union Transactions, EOS, v. 78, no. 46, p. F304.

Stewart, A., Ronan, A.D., Constantz, J., and Freyberg, D., 1997, The influence of temperature and layering heterogeneity

on transmission loss from an ephemeral stream: American Geophysical Union Transactions, EOS, v. 78, no. 46, p.

F304.
ENVIRONMENTAL TRACERS OF RECHARGE AT

ABO ARROYO, BEAR CANYON, AND THE SANTA FE RIVER,

MIDDLE RIO GRANDE BASIN, NEW MEXICO

David A. Stonestrom and Katherine C. Akstin

U.S. Geological Survey, Water Resources Division,

345 Middlefield Road, MS 421, Menlo Park, CA 94025

To quantify spatial patterns of recharge in the Middle Rio Grande Basin (MRGB), environmental indicators were measured on transects along and between arroyos entering the east margin of the basin.

This summary describes chloride and bromide results from interarroyo transects along the Santa Fe

River near La Bajada (Santa Fe County), along Bear

Canyon near Albuquerque (Bernalillo County), and

along Abo Arroyo in a 28-km reach extending approximately from Blue Springs to Veguita (Socorro

County). The Santa Fe River and Abo Arroyo are

two of the largest rivers entering the MRGB. Bear

Canyon is one to two orders of magnitude smaller

in drainage area and provides an example of the

many small mountain-front drainages ringing the

MRGB.

Continuous bulk samples of unsaturated soils and

sediments were obtained with a pneumatic-driven

core sampler driven to typical depths of 4 to 5 m. In

all, 29 vertical profiles were sampled, 17 in interarroyo areas and 12 in active channels. Two transects

were sampled along the Santa Fe River, one 0.2 km

upstream of exposed bedrock marking the mountain front, and one approximately 1 km downstream of

the mountain front. One transect was sampled in Bear

Canyon, approximately 0.3

km downstream of exposed

bedrock marking the mountain front. Four transects

were sampled along Abo Arroyo, 1.4 km upstream of the

mountain front, and 0.4, 4,

and 27 km downstream of the

mountain front.

After drying samples to determine water content, soluble

salts were extracted using

methods described in Stone

(1984). Chloride and bromide

concentrations were determined using single-column

ion chromatography with silica-bonded ion exchangers. Analytical uncertainty was about ±5%.

Pore water concentrations of chloride ranged from 3

to 5100 mg/L. Pore-water concentrations of bromide ranged from <0.02 to 62 mg/L.

The solute-profile method of Allison was used to

infer recharge rates from pore-water concentrations

of chloride (Allison and others, 1994; Edmunds and

others, 1988). A value of 0.29 mg Cl/L precipitation

was used to calculate chloride loading, based on

wet and dry deposition collected in Santa Fe, New

Mexico, from November 1987 to March 1989 (Anderholm, 1994). Local mean-annual precipitation

values were interpolated from data in Thorn and

others (1993).

Figure 14 shows profiles of water content and porewater concentrations of chloride and bromide for

two holes of an example transect near Abo Arroyo.

Bromide concentrations mimicked chloride concentrations in all profiles, with bromide-to-chloride

ratios showing considerable variation among profiles. Bromide-to-chloride ratios were lowest in

Figure 14. Profiles of water content and pore-water concentrations of chloride and

bromide at distances of 5 and 64 meters from Abo Arroyo along a transect near the

eastern margin of the Middle Rio Grande Basin, New Mexico.
Santa Fe River pore waters, averaging 0.009, and

highest in Bear Canyon pore waters, averaging 0.08.

Ethylene bromide is a gasoline additive (Brehler

and Fuge, 1978); Bear Canyon values thus probably

reflect anthropogenic additions of bromide from

metropolitan Albuquerque.

Interarroyo recharge rates based on chloride massbalance calculations evaluated at a depth of 4 m

ranged from 0.04 to 5 mm/yr (Fig. 15). A recharge

rate of even 5 mm/year over the entire basin would

provide only 4 x 107 m3 of cumulative recharge, or

one-fifth the estimated amount of ground water

withdrawn in 1990 (Thorn and others, 1993). The

Bear Canyon transect had the highest recharge rates.

The elevation of the Bear Canyon transect is about

1980 m. Sandia Crest, immediately to the east, rises

to an altitude above 3000 m. Santa Fe and Abo transects range in elevation from 1450 to 1680 m and are

located where the basin margin is significantly

lower. The relatively high recharge rates at Bear

Canyon are attributable mainly to orographic effects.

A consistent pattern of decreasing recharge rate

with increasing distance from channel was observed

in all transects (Fig. 15). It seems unlikely that chloride-loading rates varied over the short distances

(<0.5 km) of individual transects, which were characterized by gross similarities in vegetation type,

vegetation density, and elevation. The trend may be

caused by a systematic variation in near-surface hydrologic balance due to changes in particle size distribution (hence, hydrologic parameters) with distance from the channels. Evaluation of this and

other hypotheses is underway.

REFERENCES

Allison, G.B., Gee, G.W., and Tyler, S.W., 1994, Vadose zone techniques for estimating groundwater recharge in arid

and semiarid regions: Soil Science Society of America Journal, v. 58, p. 6-14.

Anderholm, S.K., 1994, Ground-water recharge near Santa Fe, north-central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 94-4078, 68 p.

Brehler, B., and Fuge, R., 1978, Bromine, in Wedepohl, K.H., (ed.), Handbook of Geochemistry: New York, SpringerVerlag, p. 35-A-1 to 35-L-2.

Edmunds, W.M., Darling, W.G., and Kinniburgh, D.G., 1988, Solute profile techniques for recharge estimation in semiarid and arid terrain, in Summers, I., (ed.), Estimation of Natural Groundwater Recharge: Norwell, Mass., D. Reidel

Publishing Co., p. 139-157.

Stone, W.J., 1984, Recharge in the Salt Lake Coal Field based on chloride in the unsaturated zone: New Mexico Bureau

of Mines and Mineral Resources Open-File Report 214, 64 p.

Figure 15. Interarroyo recharge rates inferred from solute

profiles along the eastern margin of the Middle Rio Grande

Basin, New Mexico.
Thorn, C.R., McAda, D.P., and Kernodle, J.M., 1993, Geohydrologic framework and hydrologic conditions in the Albuquerque Basin, central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 93-4149, 106

p.

THERMAL TRACKING TECHNIQUES TO ESTIMATE

STREAMFLOW AND STREAMBED INFILTRATION

ALONG THE EASTERN MIDDLE RIO GRANDE BASIN

Amy E. Stewart1,2, Anne D. Ronan3, and Jim Constantz1

1

U.S. Geological Survey, Water Resources Division, Western Region, Branch of Regional Research,

345 Middlefield Road, MS 496, Menlo Park, CA 94025 2

Department of Civil & Environmental Engineering, Stanford University, Stanford, CA 94305 3

Department of Civil Engineering, San Jose State University, San Jose, CA 95192

Proper characterization of streamflow and streambed hydraulic properties is essential for determination of the spatial and temporal variations in arroyo

streambed infiltration. Several techniques are being

developed to use stream and streambed temperature patterns to thermally track the movement of

water, both vertically and down canyon (Constantz

and Thomas, 1996, 1997; Ronan and others, 1997;

Stewart and others, 1997). Data obtained by these

techniques may then be utilized as input in computer models or to validate model simulations.

VS2DH, a two-dimensional, finite-difference model

of heat and water transport in the unsaturated zone

(Healy and Ronan 1996), is being used to simulate

percolation properties below streambeds throughout the eastern portion of the Middle Rio Grande

Basin (MRGB). Stream and streambed temperature

data are used to calibrate this model. Field sites,

representing a variety of locations in which recharge

is believed to be important in arid environments,

have been selected as representative of tributary

and mountain-front recharge. These sites include

the La Bajada reach along the Santa Fe River, a site

at the mountain front of Bear Canyon, and a lower

reach of Abo Arroyo. The Santa Fe River site represents a site of potential tributary recharge in the

wetter, northern portion of the basin, while lower

Abo Arroyo represents a site of potential tributary

recharge in the dry, southern portion of the basin.

A less extensive study is ongoing at Bear Canyon,

representing a site of potential mountain-front recharge. In each of the sites water flows over the

bedrock until reaching basin fill at the fault zones

west of the mountains. As the streamflow travels

over the more permeable alluvial material, cumulative infiltration increases until streamflow ceases

and only groundwater flow continues toward the

Rio Grande.

Although each field site is not instrumented in an

identical manner, in general the thermal tracking

protocol is as follows. At a given site, thermocouple

wire “nests” were buried to approximately 3 meters

(m). Each nest consists of five or six thermocouple

wires attached to specific locations along a wooden

guide. The assembly is inserted into a drill hole located in the low point of the stream channel. Temperature readings at multiple depths, usually along

with stream and air temperatures, are recorded at

10-minute intervals on a Campbell CR10X or 21X

data logger. (The mention of brand names does not

constitute endorsement by the USGS.) Data loggers

are situated along the stream banks either in preexisting USGS gage houses or in temporary secured

shelters. Each field site has multiple thermocouple

nests along the reach. Therefore, the water movement may be tracked as it vertically infiltrates, and

to an extent, may be tracked as it flows down canyon through the subsurface.

VS2DH is being used to model infiltration on a

transverse vertical cross-section at the Santa Fe, La

Bajada field site. A 2-D grid of the stream and bank

system was developed to model variations in

stream temperature and stage, both of which continuously fluctuate throughout the day. Simulated

temperature values are then matched to subsurface

temperature profiles from thermocouple data to

estimate streambed infiltration rates for the crosssection. Due to operational problems related to

stream diversions at the study site, only data from

one thermocouple nest (TCN2) has been modeled
using VS2DH. Initial results appear promising. For

example, for a representative period during June

1997, percolation rates at TCN2 have been estimated

to be on the order of 10-5 m/s. These values are

within the range of streambed infiltration rates reported by Thomas and Constantz for a 1-kilometer

(km) subreach of the Santa Fe River that includes

TCN2 (in these proceedings).

A second thermal-tracking technique is being developed to examine the spatial and temporal patterns in ephemeral reaches. The primary difficulty

proved to be in developing instrumentation that

will remain in place during flash-flooding events.

We are using Onsett Temperature Probes to measure streambed-surface temperatures, at 1-hour intervals, at eight locations down Abo Arroyo. The

probes are unevenly spaced down the 30-km reach,

with a majority of the probes concentrated near the

fault zone. Each probe is encased in PVC pipe, with

screened ends. The casings are tethered with aircraft cable to an anchoring steel rod, buried as deep

as 2 m in the sediment. A record of temperature is

collected, to analyze diurnal variations in streambed

temperatures. Abrupt changes, followed by significant dampening of the diurnal temperature signal

suggests the presence of streamflow at a given

probe site. A USGS gage station is located at the top

of the reach, on the bedrock. Streambed surfacetemperature probe and thermocouple-nest data

collected from Abo Arroyo will be analyzed to relate streamflow hydrographs to spatial and temporal patterns in streamflow between the gaging station and the Rio Grande. This provides an indication of the potential recharge through time across

the extent of the arroyo. A new computer program

is being developed to couple a surface-water program with VS2DH so that the location of a simulated flood-wave toe may be compared to data collected from the streambed surface-temperature

probes.

The Bear Canyon site consists of a study reach of

only 300 m, where two thermocouple nests are operating at the up-canyon and down-canyon boundaries of the study reach. Temperature data from the

thermocouple nests will be used to detect the presence and duration of streamflows. During these

periods of flow, data will be used with VS2DH to

estimate streambed-percolation rates.

References

Constantz, J., and Thomas, C.L., 1996, The use of streambed-temperature profiles to estimate the depth, duration, and

rate of percolation beneath arroyos: Water Resources Research, v. 32, no. 12, p. 3597-3602.

Constantz, J., and Thomas, C.L., 1997, Streambed-temperature profiles as indicators of percolation characteristics beneath arroyos in the Middle Rio Grande Basin, USA: Hydrological Processes, v. 11, no. 12, p. 1621-1634.

Healy, R.W., and Ronan, A.D., 1996, Documentation of computer program VS2DH for simulation of energy transport in

variably saturated porous media--Modification of the U.S. Geological Survey’s computer program VS2DT: U.S.

Geological Survey Water-Resources Investigations Report 96-4230, 36 p.

Ronan, A.D., Prudic, D.E., and Constantz, J., 1997, Effects of diurnal stream temperature variation on infiltration beneath an ephemeral stream: EOS, Transactions, American Geophysical Union, v. 78, no. 46, p. F304.

Stewart, A., Ronan, A.D., Constantz, J., and Freyberg, D., 1997, The influence of temperature and layering heterogeneity

on transmission loss from an ephemeral stream: American Geophysical Union Transactions, EOS, v. 78, no. 46, p.

F304.
SOUTHERN MIDDLE RIO GRANDE BASIN

PRELIMINARY GEOLOGIC, HYDROLOGIC, AND AEROMAGNETIC MAPS OF

THE WESTERN THREE-QUARTERS OF

THE PUEBLO OF ISLETA, CENTRAL NEW MEXICO

Florian Maldonado1, Dave W. Love2, Janet L. Slate1, V.J.S. Grauch3, Ward E. Sanford4,

Matthew Heizler2

, William C. McIntosh2, and Nancy A. Shock1

1

U.S. Geological Survey, National Cooperative Geologic Mapping,

Box 25046, MS 913, Denver, CO 80225 2

New Mexico Bureau of Mines and Mineral Resources,

801 Leroy Place, Socorro, NM 87801 3

U.S. Geological Survey, Mineral Resources,

Box 25046, MS 964, Denver, CO 80225 4

U.S. Geological Survey, Water Resources Division,

12201 Sunrise Valley Drive, MS 430, Reston, VA 20192

Parts of 12 quadrangles, encompassing the Pueblo

of Isleta, central New Mexico, are being mapped at

1:24,000 scale and compiled at 1:50,000 scale, as part

of the Middle Rio Grande Basin Study. Mapping by

the U.S. Geological Survey and New Mexico Bureau

of Mines and Mineral Resources depicts the geology, hydrology, and aeromagnetometry of the area.

Our geologic map shows the western three-quarters

of the pueblo from the Rio Puerco on the west to the

base of the Manzano Mountains on the east. The

major geomorphic features of the mapped quadrangles include the Rio Grande and Rio Puerco valleys;

Llano de Alburquerque and Llano de Manzano;

Wind Mesa, Cat Mesa, Cat Hills, and Isleta volcano

and associated flows; Hell Canyon; ManzanoManzanita piedmont slopes; Hubbell Bench; and

McCormick Ranch closed basin and playa. Major

geologic features within the area are: (1) five basaltic volcanic fields; (2) deposits of the Santa Fe

Group; (3) piedmont deposits from the Manzano

and Manzanita Mountains; (4) post-Santa Fe Group

terrace deposits; (5) calcic soils; (6) fluvial deposits

of the present Rio Puerco and Rio Grande; (7) eolian

dunes; and (8) high-angle normal faults.

The basaltic fields in the western half of the area,

from youngest to the oldest, are: Cat Hills, Black

Mesa, Isleta, Cat Mesa, and Wind Mesa. The Cat

Hills field is composed of seven lava flows and 21

cinder cones. Samples from the oldest flow have

40Ar/39Ar whole-rock ages of 0.11 ± 0.03 and 0.098 ±

0.02 Ma. An earlier K-Ar age for the oldest flow is

0.14 ± 0.04 Ma (Kudo and others, 1977). Samples

from the youngest flow have discordant 40Ar/39Ar

whole-rock ages of 0.49 ± 0.16 Ma and 0.25 ± 0.08

Ma. A dike exposed in the northernmost cinder

cone has a 40Ar/39Ar whole-rock age of 0.18 ± 0.08

Ma. This and other cinder cones are aligned on a

north-northeast striking fissure zone.

The Black Mesa basaltic lava flow is exposed eastnortheast of the Isleta field and is interbedded with

Rio Puerco sand and gravel facies of the upper part

of the Santa Fe Group. No volcanic source for this

flow has been identified. A sample from this field

has a 40Ar/39Ar age of 2.68 ± 0.04 Ma.

The Isleta field is composed of five lava flows, two

cinder cones, and one tuff ring (Kelley and Kudo,

1978). The lowest flow has a 40Ar/39Ar age of 2.75 ±

0.12 Ma and the overlying flow a 40Ar/39Ar age of

2.72 ± 0.08 Ma and an earlier K-Ar age of 2.78 ± 0.12

Ma (Kudo and others, 1977).

The Cat Mesa field consists of a thick lava flow

found locally at the base of the clay and silt facies of

the Santa Fe Group and below the calcic soils of the

Llano de Alburquerque. A sample from this field

has a 40Ar/39Ar whole rock age of 3.00 ± 0.10 Ma.

The Wind Mesa field consists of three lava flows

with minor cinder deposits. The flows are faulted

and appear to be part of an exhumed volcano. Ancestral Rio Puerco pebbles on the lava flow above

the present Santa Fe-lava flow contact support this

interpretation. A sample of the oldest flow has a

40Ar/39Ar whole-rock age of 4.01 ± 0.16 Ma.
The exposed Santa Fe Group is considered part of

the Sierra Ladrones Formation of Machette (1978),

and consists of piedmont conglomerates and sandy

siltstones, and fluvial deposits of an ancestral Rio

Puerco and ancestral Rio Grande. We have divided

the ancestral Rio Puerco deposits in the westernmost part of the map area into three lithofacies that

are based on grain size and clast content. From

youngest to oldest, the facies are: (1) sand and

gravel; (2) silt, sand, and clay; and (3) coarse sand

and gravel. The basalt of Cat Mesa, dated at about 3

Ma, is at the base of the silt, sand, and clay facies.

Along both sides of the Rio Grande valley, ancestral

Rio Puerco facies are primarily sand with pebbles

and cobbles. The ancestral Rio Grande deposits are

exposed east of the Rio Grande valley and are

mapped as a lower fine-grained facies and an upper

coarse-grained facies. The upper facies consists of

coarse sand, pebbles, and cobbles, with rare boulders of the Tshirege Member of the Bandelier Tuff,

as much as 4 m long. The Tshirege ash (1.22 Ma) is

occasionally preserved close to the contact between

the two facies.

Piedmont alluvial aprons from the ManzanoManzanita Mountains have soils that range from

Pliocene to Holocene age. A sequence of as many as

five Quaternary terraces is preserved along Hell

Canyon, which is entrenched below the oldest

piedmont alluvial apron. As many as 20 Quaternary terraces occur along the smaller tributaries.

Post Santa Fe terrace deposits are found along the

present Rio Grande inset against the Sierra Ladrones Formation. The most extensive terrace deposit makes up the Los Duranes Formation. The

Los Duranes Formation is older than the Cat Hills

flow that overlies it—dated at 0.14, 0.11, and 0.098

Ma.

West of the Rio Grande, widespread calcic soils are

mapped separately as calcic soils, and calcic soils of

the Llano de Alburquerque. The calcic soils are

younger than the soils of the Llano and are found

interbedded with and below eolian deposits. The

morphological stage of soil development (Machette,

1985) ranges from poorly developed stage I to stage

III. Stage III soils are commonly found on the flanks

of the Cat Hills cinder cones. The calcic soils of the

Llano de Alburquerque range from stage III to IV,

overlie the sand and gravel facies of the Rio Puerco,

and are overlain by the basaltic flow of the Cat

Hills. Therefore, the Llano surface is older than the

discordant range of ages (0.098 Ma to 0.49 Ma) of

the Cat Hills basalt flows and considerably younger

than the basalt of Cat Mesa (3 Ma).

East of the Rio Grande, a thick stage III to IV calcic

soil, referred to as the calcic soils at the top of the

ancestral Rio Grande, overlies the ancestral Rio

Grande sandy-gravel deposits. These deposits

contain pumice and reworked ash and large clasts

of the 1.22-Ma Tshirege Member of the Bandelier

Tuff. Locally, less developed calcic horizons in eolian sand overlie the thicker soil.

Holocene fluvial deposits are mapped in the westernmost part of the map area along the Rio Puerco

and along the Rio Grande. The Rio Puerco deposits

are divided into three terraces and the present Rio

Puerco channel. The present river channel was delineated from aerial photography dated 1990 and

has deviated as much as 1⁄4 km from the former

channel, shown on the 1952 topographic 1:24,000-

scale base. The Rio Grande valley deposits are divided into the modern floodway of pebbly sand and

fine-sand-to-clay floodplain.

Widespread eolian deposits are composed of sheets

and dunes of Holocene to Pleistocene age. These

include: (1) longitudinal dunes indicating winds

dominantly from the west-southwest; (2) dunes deposited along the escarpment edge, above the Rio

Puerco in the westernmost part of the map area and

above bluffs along the eastern margin of the Rio

Grande valley; (3) dunes deposited against topographic highs, including fault scarps; and (4) dunes

and sheets descending into the Rio Grande valley

from the Llano de Alburquerque.

A northerly striking, high-angle normal-fault zone

forms a complex of grabens, half grabens, and

horsts in the map area. From west to east, seven

major fault zones include the: Garcia (new name),

Cat Mesa, Cedar Wash (new name), Palace-Pipeline

(new name), McCormick Ranch, Hubbell Spring,

and Sanchez faults. The Garcia fault, on the western

edge of the map area, is part of a fault zone that represents the western edge of the Rio Grande Rift.

The Cat Mesa fault offsets the basalts of Cat Mesa

and Cat Hills, the calcic soils of Llano de Alburquerque, and the Santa Fe Group. The Cedar Wash,

an east-northeast-trending fault zone, was identified

southwest of the Isleta volcanic field. Another eastnorthwest-trending fault is inferred beneath part of

Hell Canyon. The Palace-Pipeline fault zone, consisting of three or more north-trending faults, displaces Santa Fe deposits along a pipeline south of
Hell Canyon and can be traced northward. The

McCormick Ranch fault is a down-to-the-east fault

east of a horst trending north from Hell Canyon.

The Hubbell Spring fault zone consists of two or

more north-northeast-trending faults. East of the

easternmost strand, lower Mesozoic and upper Paleozoic rocks deformed by Laramide compression

are exposed beneath 15 m to 30 m of old cemented

piedmont gravel and overlying finer-grained sediments.

The signatures on the aeromagnetic map correspond to the major faults and volcanic fields that

have been mapped at the surface. Both the hydrologically important Cat-Mesa and HubbellSpring faults are expressed on the aeromagnetic

map. In addition, the map suggests that some segments considered part of the Hubbell Spring fault

may not be connected.

The ground-water-level contour map shows steep

gradients in the western and eastern parts of the

map separated by a trough (Titus, 1963). The western (Cat Mesa) gradient, on the west side of the Cat

Mesa fault, may reflect the juxtaposition of fractured basaltic rocks and coarser-grained Santa Fe

Group (hanging wall, east side of fault) against

finer-grained facies of the Santa Fe Group (foot wall,

west side of fault). Another possibility is a northerly-striking fissure system that acts as a steep

ground-water barrier parallel to the Cat Mesa fault.

The alignment of the Cat Hills cinder cones and

distribution of lava flows may reflect a fissure. A

wide ground-water trough, which appears to

plunge to the south, separates the Cat Mesa gradient from the steep eastern gradient. The eastern

gradient, located along the Hubbell Spring fault,

likely represents juxtaposition of basin-fill material

with bedrock.

REFERENCES

Kelley, V.C. and Kudo, A.M., 1978, Volcanoes and related basalts of the Albuquerque Basin, New Mexico: New Mexico Bureau of Mines and Mineral Resources, Circular 156, 30 p.

Kudo, A. M., Kelley, V.C., Damon, P.E., and Shafiquallah, M., 1977, K-Ar ages of basalt flows at Canjilon Hill, Isleta

volcano, and Cat Hills volcanic field, Alburquerque-Belen Basin, central New Mexico: Isochron/West, no. 18, p.

15-16.

Machette, M.N., 1978, Geologic map of the San Acacia quadrangle, Socorro County, New Mexico: U.S. Geological

Survey Geologic Quadrangle Map GQ-1415, scale 1:24,000.

Machette, M.N., 1985, Calcic soils of the southwestern United States, in Weide, D.L., (ed.), Soils and Quaternary geology of the southwestern United States: Geological Society of America Special Paper 203, p. 1-21.

Titus, F.B., Jr., 1963, Geology and ground-water conditions in eastern Valencia County, New Mexico: State Bureau of

Mines and Mineral Resources, New Mexico Institute of Mines and Technology, Ground-Water Report 7, 113 p.
PRELIMINARY PALEOSEISMIC ANALYSIS OF A TRENCH

ACROSS THE HUBBELL SPRING FAULT

NEAR ALBUQUERQUE, NEW MEXICO

Stephen F. Personius

U.S. Geological Survey, Geologic Hazards Team,

Box 25046, MS 966, Denver, CO 80225

The Hubbell Spring fault (HSF) is a down-to-thewest, north-trending normal fault that lies 5–11 km

east of the basin-bounding Manzano fault zone in

the east-central part of the Albuquerque basin. The

HSF forms the western margin of a prominent intrabasin topographic and structural high known as

the Hubbell bench; conspicuous fault scarps mark

its length. At its northern end, the HSF merges with

the Tijeras-Cañoncito fault system at the Travertine

Hills in Sandia National Laboratories. The HSF extends south from the Travertine Hills about 34 km

to the latitude of Belen. Previous mapping and

scarp-morphology studies (Machette and McGimsey, 1983) indicate that the HSF is one of the more

recently active faults in the Albuquerque area, and

probably represents the active margin of the modern Rio Grande rift in this part of the basin. The

present study was initiated because no previous

paleoseismic studies had been conducted on the

HSF, despite its proximity to Sandia National Laboratories and the Albuquerque metropolitan area.

The goals of this study are to determine the timing,

recurrence, and estimated magnitude of the last

several paleoearthquakes on the HSF.

In September 1997, a 60-m-long exploratory trench

was excavated across the HSF on Isleta Pueblo tribal

lands 1.2 km south of the southern boundary of

Sandia National Laboratories. The trench crossed a

7-m-high scarp formed on middle Pleistocene alluvial-fan deposits derived from the Hubbell bench

and Manzano Mountains to the east (Love and others, 1996). The trench exposed two primary fault

zones (herein referred to as the eastern and western

strands) and an intervening 16-m-wide horse block

that is broken by numerous small displacement

synthetic and antithetic faults. In the upthrown

block of the eastern strand, well sorted fluvial sands

of the lower Pleistocene, upper Santa Fe Group are

unconformably overlain by fan alluvium consisting

of sandy coarse pebble and cobble gravel; a prominent stage III-IV calcic soil is formed in the upper

part of the fan deposits. Three wedges of sandy

eolian/colluvial sediment are preserved in the deformation zone. A thin layer of mixed eolian sand

and pebbly slope-wash colluvium lies unfaulted

across the fault scarp at the surface of the trench.

Comparisons between sandy eolian/colluvial

wedges and fault-scarp colluvial wedges described

elsewhere in the western U.S. (summarized in

McCalpin, 1996) suggest that each of the sandy

wedges exposed in the trench formed in response to

a surface-rupturing earthquake. The oldest wedge

lies unconformably on fan deposits, appears to

thicken to as much as 150 cm in the downthrown

blocks of both the eastern and western fault strands,

and is preserved across most of the fault scarp. Its

presence in the upthrown block 15 m east of the

eastern strand as well as in the downthrown block

of the western strand suggests that it was deposited

after formation of fault scarps on both the eastern

and western fault strands. This wedge has subsequently been faulted about 30 cm across the eastern

strand and at least 60 cm across the western strand.

The intermediate wedge is primarily preserved

from the eastern strand westward, suggesting that it

formed after a second surface-rupturing earthquake

on the western strand. Additional evidence for a

second event includes the presence of several upward-truncated fractures and a buried stage II-III

calcic soil at the boundary between the oldest and

intermediate wedges. The intermediate wedge has

a maximum thickness of about 130 cm in the hanging wall of the western strand, although extensive

rodent burrowing adjacent to the western strand

prevents measurement of its maximum thickness.

This wedge has subsequently been faulted about 30

cm across the eastern strand and about 40 cm across

the western strand. The youngest wedge thickens

to about 100 cm just west of the western fault

strand, and is preserved only in the hanging wall

and about 5 m of the horse block. This wedge is

unfaulted and lies on an eroded scarp free-face cut

into the intermediate wedge in the horse block.

The composition and geometry of the eolian/colluvial wedges indicate that they were

probably formed by a combination of eolian sand

deposition by prevailing westerly winds and collu-
viation from eroded fault scarps formed during

three surface-rupturing earthquakes. Climatically

driven episodes of eolian sand deposition may be

reflected as thin buried soils within the wedges, but

the thickness of these sedimentary packages indicates that infrequent surface-faulting events probably created the space needed for wedge deposition

and preservation. Because eolian processes can

rapidly bury landforms in this environment, wedge

thickness is probably a reasonable approximation of

vertical offset associated with individual surfacerupturing earthquakes. The thickness of preserved

wedges (1–1.5 m) indicates a likely range in offset of

1–2 m at the trench site. This range is reasonable,

given that the number of probable events (3) and

net vertical offset in the underlying alluvial fan deposits (4.7 m) indicate an average net vertical offset

of about 1.6 m per surface faulting event. Comparisons between rupture parameters associated with

large historic normal-fault earthquakes elsewhere

(Wells and Coppersmith, 1994), a mapped fault

length of 34 km, and offsets of 1–2 m yield estimated earthquake magnitudes of Mw 6.9–7.1 for the

last three surface-rupturing earthquakes on the

HSF.

The timing of surface-rupturing earthquakes on the

HSF is presently unknown, but soil data and pending TL ages on wedge deposits should allow determination of two recurrence intervals and the

elapsed time since the most recent event. Preliminary soil data suggest that the most recent event

occurred at least several tens of thousands of years

before present, and that recurrence intervals between events may be of similar or longer duration.

REFERENCES

Love, D.W., Hitchcock, C., Thomas, E., Kelson, K., Van Hart, D., Cather, S., Chamberlin, R., Anderson, O., Hawley, J.,

Gillentine, J., White, W., Noller, J., Sawyer, T., Nyman, M., and Harrison, B., 1996, Geology of the Hubbell Spring

7.5-min quadrangle, Bernalillo and Valencia Counties, New Mexico: New Mexico Bureau of Mines and Mineral

Resources Open-File Digital Map OF-DM 5, 7 p. pamphlet, 1 sheet, scale 1:24,000.

Machette, M.N., and McGimsey, R.G., 1983, Quaternary and Pliocene faults in the Socorro and western part of the Fort

Sumner 1° x 2° quadrangles, New Mexico: U.S. Geological Survey Miscellaneous Field Studies Map MF-1465,

scale 1:250,000.

McCalpin, J.P., 1996, Paleoseismology: San Diego, Academic Press, 588 p.

Wells, Donald, and Coppersmith, K.J., 1994, New empirical relationships among magnitude, rupture length, rupture

width, rupture area, and surface displacement: Bulletin of the Seismological Society of America, v. 84, p. 974-1002.
MOUNTAIN-FRONT RECHARGE

ALONG THE EASTERN SIDE OF THE MIDDLE RIO GRANDE BASIN,

CENTRAL NEW MEXICO

Scott K. Anderholm

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

Mountain-front recharge along the eastern side of

the Middle Rio Grande Basin is an important component of recharge to the basin-fill aquifer. Mountain-front recharge occurs along the interface between the basin-fill deposits and the bedrock of the

surrounding mountains (mountain front). Little is

known about the volume of mountain-front recharge to the basin-fill aquifer because there have

been few studies. This article discusses mountainfront recharge, factors that affect mountain-front

recharge, and methods that have been used to estimate mountain-front recharge, and presents estimates of mountain-front recharge for one area along

the eastern side of the basin.

Mountain-front recharge to the basin-fill aquifer can

be divided into two components: (1) subsurface

flow of ground water from the mountainous areas

to the basin-fill aquifer; and (2) infiltration of

streamflow from streams or channels that drain the

mountainous areas. Several factors influence the

quantity of each component. The volume of precipitation in the mountainous areas is a major factor

influencing mountain-front recharge. The volume

of winter precipitation relative to summer precipitation partially determines the volume of water

available for recharge because the evapotranspiration rates are much larger in the summer than in the

winter. The permeability of the bedrock in the

mountainous areas and the basin-fill deposits can

also affect the volume of mountain-front recharge

and the relative importance of the two different

components of mountain-front recharge. The volume of subsurface flow of ground water from the

mountainous areas to the basin-fill aquifer is difficult to estimate or measure directly. Streamflow at

the mountain front can be measured, thereby allowing estimation of the volume of mountain-front

recharge resulting from infiltration of streamflow.

Methods for estimating mountain-front recharge or

one of its components can be grouped into water

balances, ground-water-flow models, rainfall/runoff relations, or chemical balances. Waterbalance methods generally use estimates of precipitation, evapotranspiration, sublimation, and

runoff to calculate mountain-front recharge as a residual. Ground-water-flow models are used to calculate water levels and water balances. The volume

of mountain-front recharge can be adjusted until the

model simulates the known water levels and other

measured components of the water balance. Rainfall/runoff methods have been used to estimate

streamflow at the mountain front from ungaged

mountainous watersheds. Regression equations

generally are developed using streamflow data

from gaged watersheds that have characteristics

similar to those of watersheds where the equations

will be applied. Precipitation (mean annual or

mean-annual winter precipitation) and watershed

or basin area are the most common variables used

in the regression equations. The estimates of

streamflow made using the regression equations are

used to estimate the infiltration of streamflow component of mountain-front recharge. Chemicalbalance methods use estimates of mean annual precipitation and the concentration of a relatively conservative solute in precipitation and ground water

near the mountain front to estimate mountain-front

recharge.

Two rainfall/runoff methods and a chemicalbalance method were applied to an area of the Manzano Mountains along the eastern side of the Middle Rio Grande Basin (Fig. 16). The bedrock in this

area of 60.8 square miles (157.5 km2) consists of

relatively impermeable Precambrian igneous and

metamorphic rocks. The volume of mean annual

precipitation is about 65,200 acre-feet and the volume of mean-annual winter precipitation is about

28,600 acre-feet. Mean annual precipitation is about

20.1 in (51 cm), and mean-annual winter precipitation is about 8.8 in (22 cm).

Rainfall/runoff equations that were developed to

estimate runoff from mountainous areas in southern

Colorado (eq. 1) and southern New Mexico (eq. 2)

were used to estimate streamflow at the mountain

front of the Manzano Mountains area.
Figure 16. Albuquerque Basin and area where mountain-front recharge was estimated (modified from McAda, 1996).
Q=0.0552 A0.977 Pw3.596

(Hearne and Dewey, 1988, p. 31) (1)

Q=0.123 A1.65 P1.35

(Waltemeyer, 1994, p. 3) (2)

where Q is mean annual streamflow, in acre-feet; A

is area, in square miles; Pw is mean-annual winter

precipitation, in inches; and P is mean annual precipitation, in inches.

The streamflow at the mountain front, or the water

available for mountain-front recharge as the result

of infiltration of streamflow from the mountainous

area, was about 7,600 acre-feet using equation 1 and

about 6,200 acre-feet using equation 2. These estimates represent the maximum volume of surface

water that could infiltrate and recharge the basin-fill

aquifer because part of this water could evaporate

or be transpired prior to or during infiltration.

These values underestimate mountain-front recharge because they do not include subsurface flow

of ground water from the mountainous area to the

basin-fill deposits. The bedrock in the Manzano

Mountains area is relatively impermeable, however,

and subsurface inflow of ground water probably is

small.

A chloride-balance method results in an estimate of

mountain-front recharge for the Manzano Mountains area of about 3,900 acre-feet using the following equation (Anderholm, 1994):

R=Pt Cp/Cgw (3)

where R is mean-annual mountain-front recharge,

in acre-feet; Pt is mean annual precipitation, in acrefeet; Cp is the chloride concentration in precipitation (0.3 milligram per liter); and Cgw is the chloride concentration in ground water near the mountain front (5.0 milligrams per liter).

Although the methods use different approaches and

assumptions, the estimates of mountain-front recharge calculated using the rainfall/runoff methods

(7,600 and 6,200 acre-feet per year) and the chloridebalance method (3,900 acre-feet per year) are similar. Based on these estimates, 6 to 12 percent of the

mean annual precipitation in the Manzano Mountains area results in mountain-front recharge to the

basin-fill aquifer.

REFERENCES

Anderholm, S.K., 1994, Ground-water recharge near Santa Fe, north-central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 94-4078, 68 p.

Hearne, G.A., and Dewey, J.D., 1988, Hydrologic analysis of the Rio Grande basin north of Embudo, New Mexico,

Colorado and New Mexico: U.S. Geological Survey Water-Resources Investigations Report 86-4113, 244 p.

McAda, D.P., 1996, Plan of study to quantify the hydrologic relations between the Rio Grande and the Santa Fe Group

Aquifer System near Albuquerque, central New Mexico: U.S. Geological Survey Water-Resources Investigations

Report 96-4006, 58 p.

Waltemeyer, S.D., 1994, Methods for estimating streamflow at mountain fronts in southern New Mexico: U.S. Geological Survey Water-Resources Investigations Report 93-4213, 17 p.
PRELIMINARY RESULTS OF AQUIFER-RECHARGE ESTIMATES

INTERPRETED FROM CENTRIFUGE HYDRAULIC

PROPERTY MEASUREMENTS, ABO ARROYO,

MIDDLE RIO GRANDE BASIN, NEW MEXICO

Angus M. Lewis and John R. Nimmo

U.S. Geological Survey, Water Resources Division, Branch of Regional Research,

345 Middlefield Road, MS 421, Menlo Park, CA 94025

Abo Arroyo is an important source of tributary recharge in the Middle Rio Grande Basin (MRGB);

therefore, recharge-rate measurements in and near

the arroyo are valuable. We have measured unsaturated hydraulic conductivity (K) for ten core samples from Abo Arroyo and adjacent terraces using

the steady-state centrifuge method (SSCM), and

have interpreted point-recharge estimates from

these results. These samples came from four locations along a 30-km reach, from depths of 0.4 to 5.4

m.

Accurate measurement of unsaturated hydraulic

conductivity (K) and soil moisture can indicate

long-term average-recharge rates at selected geographic points (Nimmo and others, 1994). This

method requires core samples from deep enough

such that moisture fluctuations are negligible, implying that water flow is steady. If the matric pressure gradient is known, or if it can be assumed to be

negligible, the value of K at the field-water content

can indicate downward flux density (q). This can be

interpreted as the long-term average-recharge rate

at the position of the sample. The steady-state centrifuge method (SSCM) is well suited for the required measurements because it gives K values in

the low-water-content range important at arid and

semi-arid sites. We used the steady-state centrifuge

method in conjunction with the unsaturated flow

apparatus (UFA) (Conca and Wright, 1992) to

measure unsaturated hydraulic conductivity of the

core samples. The samples were taken in the field

using a Geoprobe (Stonestrom and Akstin, 1998),

and the UFA was modified for use with these core

samples. (Mention of brand names does not constitute endorsement by the U.S. Geological Survey.)

Each sample was run through a series of steadystate measurements covering a range of unsaturated

hydraulic conductivity values such that the corresponding water contents bracketed the field-water

content of the samples. This permitted an estimate

of K at the field-water contents. Assuming gravity

alone drives flow, these K values directly indicate q.

Preliminary results give q estimates that range from

1 to 2700 cm/yr for core samples taken within the

active channel. For samples taken 5 to 500 m away

on the adjacent terraces, q estimates are less than

5x10-5 cm/yr, suggesting that recharge rates drop

off sharply outside the arroyo. Comparing different

depths, two core samples taken from a single borehole within the active channel, 0.4 and 0.5 m below

the surface, show very different recharge rates (60

and 470 cm/yr). These values are significantly less

than estimated q values for two core samples taken

from the same borehole at depths of 1.9 and 2.0 m

(2300 and 2700 cm/yr). This variation with depth

suggests that the two shallower samples are not

deep enough to assume steady flow. The approximate equality of recharge rates from the two samples taken at 1.9 and 2.0 m, however, is consistent

with the assumptions of our method. Aside from

the uncertainty in steadiness of flow, there is possible additional error if matric potential gradients are

large enough to invalidate the assumption of flow

driven by gravity alone. To evaluate these uncertainties and the possibility of lateral flow, SSCM

measurements will be interpreted by a mathematical simulation of Darcian flow (Nimmo and others,

1996, 1997). Lateral flow is also important for the

evaluation of the total quantity of recharge from

Abo Arroyo.

Results show that recharge rates vary along the

reach within the active channel. Four samples,

taken at three different locations within the active

channel, give results consistent with the assumptions of our method. Three of these samples have q

estimates that fall in a relatively narrow range of

1900 to 2700 cm/yr; the q estimate of the fourth is

only 1 cm/yr. Of the three locations along the arroyo, the highest recharge estimates (2300 and 2700

cm/yr) come from the upper reaches (canyon) of

Abo Arroyo. The lowest recharge rate (1 cm/yr)

occurs 2.5 km downstream, where Abo Arroyo enters the basin plain. The recharge rate appears to

increase again (1900 cm/yr) 27 km downstream.

Further SSCM core-sample measurements where
Abo Arroyo enters the basin plain will test the validity of the lowest recharge rate.

Results thus far indicate the steady-state centrifuge

method (SSCM) is useful for estimating pointrecharge rates, provided the core samples are deep

enough such that flow is steady and driven by

gravity alone. Further core-sample measurements

will provide more point-recharge estimates, and a

mathematical simulation of Darcian flow will allow

us to evaluate the assumptions of steady flow and

uniform matric potential, and to evaluate the possibility of lateral flow. Current results suggest that

recharge in the arroyo itself is substantial, while

recharge on the adjacent terraces appears to be negligible.

REFERENCES

Conca, J.L., and Wright, J., 1992, Diffusion and flow in gravel, soil, and whole rock: Applied Hydrogeology, v. 1, p. 5-

24.

Nimmo, J.R., Stonestrom, D.A., and Akstin, K.C., 1994, The feasibility of recharge rate measurements using the steady

state centrifuge method: Soil Science Society of America Journal, v. 58, p. 49-56.

Nimmo, J.R., Deason, J.A., Liaw, S.J., Izbicki, J.A., and Martin, P., 1996, Measurement and interpretation of recharging

fluxes through layered alluvium under a Mojave Desert wash [abs.]: Fall meeting, American Geophysical Union,

San Francisco, EOS, v. 77, no. 46, p. F283.

Nimmo, J.R., Deason, J.A., Izbicki, J.A., and Martin, P., 1997, Measurements and theory to determine recharge and

horizontal spreading under a Mojave Desert wash [abs.]: Annual meeting, Soil Science Society of America, Anaheim, CA, 1997, Agronomy Abstracts, p. 170.

Stonestrom, D.A., and Akstin, K.A., 1998, Environmental tracers of recharge at Abo Arroyo, Bear Canyon, and the

Santa Fe River, Middle Rio Grande Basin, New Mexico, in Slate, J.L., (ed.), Middle Rio Grande Basin Study—Proceedings of the second annual workshop, Albuquerque, New Mexico, February 10-11, 1998: U.S. Geological Survey Open-File Report 98-337.
GIS/DIGITAL INFORMATION

THE MIDDLE RIO GRANDE BASIN DIGITAL CARTOGRAPHY PROGRAM

OF THE NEW MEXICO BUREAU OF MINES AND MINERAL RESOURCES

David J. McCraw, Paul W. Bauer, and Glen E. Jones

New Mexico Bureau of Mines and Mineral Resources,

801 Leroy Place, Socorro, NM 87801

<djmc@nmt.edu>

Modern, accurate geohydrologic map information

provides essential base data for government planning and scientific study. The New Mexico Bureau

of Mines and Mineral Resources (NMBMMR), an

active participant in the ongoing Middle Rio Grande

Basin Study, has developed a new series of openfile, digital geologic-quadrangle maps (OF-DM).

(See current availability of OF-DM series below.)

These maps, funded by matching-funds grants of

the National Geologic Mapping Act STATEMAP

program, coordinated by the U.S. Geological Survey

(USGS) and NMBMMR, provide the public with

prompt, new geologic data at scales of either

1:24,000 or 1:12,000. We produce a variety of formats: (1) high-quality multicolor inkjet plots complete with cross sections, unit descriptions, and correlation charts; (2) a collection of ARC/INFO® coverages for GIS (Geographic Information Systems)

users; and (3) digital PostScript files of OF-DM

plots.

We follow a standard process for the production of

our digital map products. Geologic data are compiled from field mapping, aerial photo interpretation, borehole cuttings, correlation of electricalconductivity logs, etc. Geologic line-work (contacts,

structures, and symbology) is inked onto a greenline, mylar stable-base and scanned at 100% at 400

dpi (dots per inch) on an INTERGRAPH

ANATECH® large-format drum scanner (courtesy

of the USGS-National Cooperative Geologic Mapping Program). The resulting TIFF line-work file is

rubber-sheeted to geo-referencing tick marks generated in ARC/INFO®. This file is exported along

with the ticks as an Adobe Illustrator® file to Macintosh Macromedia FreeHand®, where the linework is drafted, unit polygons are assigned CMYK

(cyan, magenta, yellow, black) colors, and type is

set. This process essentially eliminates potential

errors introduced by a digitizer-operator, and produces smaller digital files that contain lines with

smooth curves made from a minimum number of

points (nodes) and offset-printing quality type. We

then export the drafted line-work as individual layers for all individual line attributes as DXF files to

ARC/INFO®, where they are converted into ARC

coverages for GIS users. We register the completed

geologic map FreeHand® file to a TIFF DRG (digital

raster graph) quadrangle base (which has been

cleaned in Adobe Photoshop® and turned transparent in FreeHand®). We export the map as a PostScript file to Image Alchemy®, which rasterizes the

file for inkjet plotting on demand. Through this

multi-platform process, we provide the public with

superior paper and digital geohydrologic products,

we increase NMBMMR’s cartographic production

efficiency, and we can easily revise NMBMMR’s

peer-reviewed Geologic Map (GM) series, which are

printed by offset press.

Current Open-File Digital Geologic-Quadrangle Maps Available

7.5-Minute Quad OF-DM # Scale (1:--)

Sandia Park 1 12k, 24k

Placitas 2 12k, 24k

Albuquerque East 3 24k

Hubbell Spring 5 12k, 24k

Alameda 10 24k
USING GIS TO PRODUCE A DIGITAL GEOLOGIC MAP:

THE LOS LUNAS QUADRANGLE,

AN EXAMPLE FROM THE MIDDLE RIO GRANDE BASIN, NEW MEXICO

Janet L. Slate and Nancy A. Shock

U.S. Geological Survey, National Cooperative Geologic Mapping Team,

Box 25046, MS 913, Denver, CO 80225

<jslate@usgs.gov>

The Central Region – National Cooperative Geologic Mapping Team of the Geologic Division of the

U.S. Geological Survey is compiling a digital geologic map-database of the Middle Rio Grande Basin,

New Mexico. The database will cover the Albuquerque, Belen, and Los Alamos 1:100,000-scale

map sheets as well as portions of adjacent 100,000-

scale map sheets. The Los Lunas quadrangle, which

encompasses the Rio Grande floodplain, is a prototype of the map-database. The map-database will

provide geologic, geophysical, and water-well information useful to water-resource engineers and

land-use planners.

We obtained the 1:24,000-scale DLG (digital line

graph) file of the Los Lunas quadrangle from the

Global Land Information System (GLIS) of the

USGS National Mapping Division to use as a background during air photo interpretation. (Go to

http://edcwww.cr.usgs.gov/Webglis/glisbin/-

glismain.pl for a list of data sets supported by

GLIS.) This initial step circumvents the traditional

analog compilation of geology onto a scale-stable

mylar base (so-called “green-line mylar”), and allows us to compile geology directly into digital

form. We use a computerized photogrammetric

mapping system which consists of Carl Zeiss Inc.

CADMAP® software and a digital Kern PG-2 stereoplotter. A stereo pair of air photos are mounted on

the PG-2 and scaled to the map base such that a location examined in stereo on the air photos corresponds to the same location on the digital map.

Thus geology interpreted from air photos and field

work may be transferred precisely to the digital file

while viewing the area in stereo. Sample locations,

faults, or geologic units may also be compiled in the

digital file from a paper or mylar topographic quadrangle map during this procedure. The hardcopy

map, which is affixed to a digitizing tablet, is also

scaled to the digital map. Existing geologic, fault,

soils, or other thematic maps may be brought in as a

digital background to aid in compilation. If these

are not available digitally, they can be scanned or

digitized. Beginning with a digital map base enables us to save time by eliminating the steps taken

to convert data from analog to digital.

Accurately placed symbols in the digital geologic

map-database show locations of field observations,

sampling sites, measured sections, drill holes, and

cross sections. Using the mouse of the computer to

“click” on the symbol activates the retrieval of supplemental information from the database. Such information includes annotated photographs of important field sites, analytical data of samples,

graphical representations of measured stratigraphic

sections, drill holes, and cross sections, and downhole or airborne geophysical data where available.

We used ARC/INFO® and ArcView® to construct

the digital map-database. The digital map products

resulting from this study will enable users to easily

and quickly access the information they want for the

Middle Rio Grande Basin.
HISTORICAL MAP RESEARCH

FOR THE MIDDLE RIO GRANDE BASIN STUDY

Stewart Wright

U.S. Geological Survey, Rocky Mountain Mapping Center,

Box 25046, MS 509, Denver, CO 80225

Introduction

Many geographic information system (GIS) studies

deal with the past as well as the present. Maps produced before the availability of aerial photography

(1934) provide an important source of historical

geographic information for establishing baseline

conditions. Thematic information, such as urban

extents and transportation, can be collected from

historical maps to analyze man’s impact on the land

surface through time. More recent editions of historical maps can be used as ancillary data for interpreting landscape change from historical and current aerial photographs.

The purpose of this research was to identify historical editions of U.S. Geological Survey (USGS) maps

for the Middle Rio Grande Basin Study area. The

following parameters were defined: (1) geographic

extent of the project; (2) information needed by

project personnel to decide which historical maps to

use; (3) map series to be researched; (4) map acquisition strategies; and (5) the formats for the research

results.

Methodology

An important source used for this research was Map

Index to Topographic Quadrangles of the United States,

1882 – 1940 (Moffat, 1985.) The author describes

this book as “a graphic bibliography of out-of-print

topographic maps published from 1882 to 1940 in

the 15-, 30-, and 60-minute series for all states except

Alaska.” One section contains a state-by-state list of

areas of pre-1940 large-scale (1:24,000- and 1:31,680-

scale) topographic maps.

The book has an alphabetical published map list

and map index for each state. Each map list contains the quadrangle names, survey dates, map scale

(expressed by minutes of latitude and longitude),

and map-index key numbers. The index maps show

the geographic extent of the historical maps and are

keyed to the corresponding numbers shown in the

published map lists. The map indexes and lists in

this book were used to check the completeness of

historical map coverage data obtained in the computer-file searches.

Historical copies of USGS topographic map indexes

were used for data verification. These indexes usually cover a single state and show the geographic

extent of maps at various scales. Most of the indexes consulted were published in the early 1950's.

Records where only the date of printing differs reflect reprints of earlier map editions. Because map

content was the same, only one of these versions

needed to be acquired.

The first phase of the research involved pre-1934

USGS mapping because information for those maps

was already available from the USGS Historical

Map Archive database in Reston, Virginia. The data

file for this archive contains approximately 12,500

records. All map scales and types, including special

maps and advance sheets, were listed. On the basis

of the previously defined query parameters, the

following information was obtained for each historical map within the Middle Rio Grande Basin

Study area: southeast corner latitude-longitude coordinates, map names, scales, and dates of publication, survey, reprint, and revision. This information

allows researchers to identify maps produced during specific time periods and those that are simply

reprints of earlier editions with no changes in map

content.

Data for the second phase of the research were retrieved from the USGS Map Catalog (MAPCAT),

which is under development for internal USGS use.

Not all historical maps are listed in MAPCAT, and

some maps have incomplete field entries. Twenty

map-series queries were done for the Middle Rio

Grande Basin Study. MAPCAT query results for

each historical map included current or historical

status, southeast corner latitude-longitude coordinates, map names, scale, map-series identifiers, and

dates of publication, survey or field check, reprint,

and revision.

The USGS Earth Science Information Centers have

microfiche of many historical USGS editions; an investigator could review these to identify which

maps would be useful for characterizing man’s im-
pact on the landscape through time. Other potential

sources of historical maps are map depositories,

such as libraries and educational institutions, historical societies, and state and local government

agencies.

Conclusion

The historical map-query results from the USGS

Historical Map Archive and from MAPCAT tables

were supplied to the USGS Middle Rio Grande Basin researchers who will decide which historical

maps to acquire for characterizing landscape

changes in the Middle Rio Grande Basin through

time.

Determining the existence of historical maps can be

a challenge owing to multiple map archives and

different database structures. For efficient searches

the following criteria need to be defined: geographic extent of the project, map series or types to

be investigated, attributes needed to identify historical maps, and the storage formats for retaining

historical map-query results.

REFERENCE

Moffat, R.M., 1985, Map index to topographic quadrangles of the United States, 1882 – 1940: Western Association of

Map Libraries, Occasional Paper No. 10.

URBAN DYNAMICS OF THE MIDDLE RIO GRANDE BASIN

David J. Hester

U.S. Geological Survey, Rocky Mountain Mapping Center,

Box 25046, MS 516, Denver, CO 80225

Introduction

Urban dynamics is the study of land transformations occurring in metropolitan areas through time.

A new housing subdivision, such as Huning Highlands, or a new shopping center, such as Winrock,

are examples of land transformations. Analyzing

the rate of land-use change, and calculating increases in population density, housing-unit density,

density of the transportation network, and waterconsumption rates are techniques to characterize

growth-driven land transformations. Urban growth

in the Albuquerque area is resulting in increasing

ground-water withdrawal which reduces flow in

the Rio Grande (McAda, 1996). Modeling to predict

urban growth helps us understand the impact of

urbanization on the region’s water resources, economy, and people.

Population Growth

From 1900 to 1990, the population of New Mexico

increased from 195,000 inhabitants to 1,515,000

(Chourre and Wright, 1997). The City of Albuquerque contributed 30 percent to New Mexico’s population growth during this time. In 1990, the population of the Middle Rio Grande Basin (MRGB) was

about 564,000, which amounted to about 35 percent

of the inhabitants of the state of New Mexico (U.S.

Department of Commerce, 1991). The Albuquerque

area accounts for about 90 percent of the residents

of the MRGB. Until the 1970's, growth was greatest

in the North Valley and East Mesa of Albuquerque;

however, lower land prices drove urbanization to

the West Side area in the mid-1980's. The Greater

West Side Area, including Rio Rancho and Corrales,

accounted for 60 percent of Albuquerque’s total urban growth between 1980 and 1995 (Middle Rio

Grande Council of Governments, 1997). If Rio Rancho’s population continues to increase at the same

growth rate, the municipality will soon surpass

Santa Fe as the second largest city in New Mexico.

Land Transformations

From 1970 to 1990, a 1-percent increase in national

population resulted in a 6- to 12-percent increase in

land use (Middle Rio Grande Council of Governments, 1997). These transformations from land

cover to land use have typically meant a decrease in

areas conducive to ground-water recharge such as

agricultural lands, forestlands, and wetlands. From

1945 to 1992, general land-use trends for the south-
western U.S. were the transformation of forest and

pasture land to transportation, industrial, and urban

uses (O’Donnell, 1997). In the Albuquerque area,

14,000 acres were irrigated in 1975, compared to

9,600 acres in 1992 (McAda, 1996). Concomitant

with a 30-percent decline in irrigated agriculture,

from 1973 to 1991, urbanized land in the Albuquerque metropolitan area grew by about 70 percent or

35,000 acres (Braun and others, 1997).

Water Consumption

Albuquerque’s annual ground-water withdrawal

has increased from about 2,000 acre-feet in 1933 to

about 123,000 acre-feet in 1994, with more than 50

percent of the withdrawal occurring from 1980 to

1994 (McAda, 1996). New high-technology industries, for example, Intel’s Rio Rancho plant which

consumed nearly 4-million gallons per day in 1996,

place a high demand on existing ground-water resources. Natural resources, such as water, sustain

an urban area’s economic and population growth.

The availability, collection costs, and distribution of

water resources influence future land-use patterns.

Urban-Growth Modeling

An urban-growth model (UGM) can be used to predict future urbanization. The UGM produces both

quantitative data and a pictorial view of predicted

urban expansion. The USGS-NMD plans to use the

UGM for a pilot area in the MRGB encompassing

Albuquerque, Rio Rancho, Edgewood, and Moriarty. The UGM requires datasets of historical urban

extent, slope, historical roads, areas excluded from

development, and shaded relief. The UGM incorporates four types of growth—spontaneous, diffusive,

organic, and road-influenced—as well as five

growth parameters and five growth constants

(Clarke et al., 1996a, 1996b). Aerial photographs

from 1935, 1951, 1973, and 1996 will be interpreted

to map historical urban extent and to calibrate

model output. Calibration is an iterative process;

that is, actual growth in each successive aerial photo

is compared with that predicted by the UGM. Initial growth values are then modified such that predicted urban area matches actual urban area recorded in the aerial photographs. Once calibration

is complete, the UGM can predict future urbanization for a time period similar to that of the historical

data.

Conclusion

From 1891 to 1995, the developed Albuquerque

metropolitan area increased from 2000 acres to

103,000 acres (Price, 1996). Public and Indian lands

cover approximately 40 percent, or 3,900 square

miles, of the MRGB (Middle Rio Grande Council of

Governments, 1997) which will likely constrain future urban growth. The USGS-MRGB urban-growth

modeling will help identify areas of future urbanization and analyze the potential impacts of the resulting urban-land transformation.

REFERENCES

Braun, Paul, Chourre, Martin, Hughes, Dave, Schubert, Jamie, Streibek, Heike, and Thorstad, Rick, 1997, Land use

change in the Albuquerque Metropolitan Area: U.S. Geological Survey,

http://geochange.er.usgs.gov/sw/changes/anthropogenic/albuquerque/.

Chourre, Martin, and Wright, Stewart, 1997, Population growth of the Southwest United States, 1900-1990: U.S. Geological Survey, http://geochange.er.usgs.gov/sw/changes/anthropogenic/population/.

Clarke, K.C., Hoppen, S., Gaydos, L., 1996a, Methods and techniques for rigorous calibration of a cellular automaton

model of urban growth, Third International Conference/Workshop on Integrating GIS and Environmental Modeling:

Santa Fe, New. Mexico, National Center for Geographic Information and Analysis, University of California, Santa

Barbara.

Clarke, K.C., Hoppen, S., Perez, S., 1996b, Clarke Urban Growth Model: U.S. Geological Survey,

http://geo.arc.nasa.gov/usgs/clarke/hilt.html.

McAda, D.P., 1996, Plan of study to quantify the hydrologic relations between the Rio Grande and the Santa Fe Group

Aquifer System near Albuquerque, central New Mexico: U.S. Geological Survey Water-Resources Investigations

Report 96-4006, 58 p.

Middle Rio Grande Council of Governments, DRAFT October 15, 1997, FOCUS 2050 snapshot: Existing conditions,

significant trends, and projections in the Middle Rio Grande Region: Albuquerque, New Mexico, 34 p.

O’Donnell, Michael, 1997, Land use trends in the southwestern United States: U.S. Geological Survey,

http://geochange.er.usgs.gov/sw/changes/anthropogenic/cropland/.

Price, V.B., 1996, Albuquerque’s environmental story—People create their own environment: Albuquerque, New Mexico, http://www.cabq.gov/aes/s2arch.html.
U.S. Department of Commerce, 1991, 1990 census of population and housing; Summary population and housing characteristics, New Mexico: 1990 CPH-1-33, variously paged.

MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS

LAND-USE ANALYSIS MODEL

Mike Corlett1 and David Abrams2

1

Planning Technologies, LLC,

6801 Jefferson, N.E., Suite 100, Albuquerque, NM 87109 2

Middle Rio Grande Council of Governments,

317 Commercial, N.E., Suite 300, Albuquerque, NM 87102

We designed a model, called the Land Analysis

Model (LAM), to allocate forecast population and

employment growth to a conceptual land-use plan.

Planning Technologies and their subcontractor,

Earth Data Analysis Center (EDAC), built the model

in ArcView® to Middle Rio Grande Council of Governments (MRGCOG) specifications. It is being

built to support the Focus 2050 Regional Plan but

should have applications for other planning activities, especially area studies and corridor studies.

Currently the Focus 2050 region has a population of

approximately 700,000 with an employment of

350,000. The MRGCOG has forecast that the region

will grow to a population of 1,555,000 and an employment of 854,000 by 2050 (MRGCOG, 1997). The

average, annual-population growth rate is forecast

at about 1.5 percent.

We gave a demonstration of LAM at the Middle Rio

Grande Basin Study Workshop, on February 10,

1998, which illustrated the following features:

(1) Construction of alternative land-use scenarios;

(2) Development of a known developments layer to

enhance the Existing Land Use;

(3) Development and operation of scoring layers

within LAM;

(4) Allocation of projected housing and employment constrained by regional control totals;

(5) The iterative functioning of LAM; and

(6) Output from LAM.

We can process housing and employment outputs

from LAM to develop a socioeconomic data set including population, housing, and employment by

type. This socioeconomic data set can be input into

other models such as transportation models.

REFERENCE

Middle Rio Grande Council of Governments, 1997, Socioeconomic Estimates and Forecasts to 2050 for State Planning

and Development District 3 and Southern Santa Fe County: Middle Rio Grande Council of Governments TR-127,

Albuquerque, New Mexico.
MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS

EXISTING LAND-USE INVENTORY

Shohreh Day and Carol S. Harlan

Middle Rio Grande Council of Governments

317 Commercial, N.E., Suite 300, Albuquerque, NM 87102

The Middle Rio Grande Council of Governments

(MRGCOG) of New Mexico is spearheading Focus

2050, a land-use planning effort that will produce a

long-range vision and strategy for managing

growth and development in the region. The Focus

2050 region includes Bernalillo, Sandoval, Torrance,

and Valencia Counties, and southern Santa Fe and

northern Socorro Counties. Planning Technologies,

LLC, and Earth Data Analysis Center developed a

geographic information system (GIS) Land-Use

Analysis Model (LAM) using ArcView® software to

construct various alternative future land-use scenarios and to allocate forecast socioeconomic variables. The MRGCOG is working cooperatively with

the National Mapping Division, U.S. Geological

Survey in Denver on land-use and land-surface

characterization aspects of the Middle Rio Grande

Basin Study. National Mapping Division provided

aerial photography, base maps and slope analyses

in support of the Focus 2050 Regional Plan.

An Existing Land-Use Inventory (ELUI) for the entire region was created to support the LAM scenario-development module and the public-input

components of the regional planning process. We

classified 18 land-use categories. The ELUI reflects

land use in the region for the period from late 1996

to early 1997. The ELUI was developed in

ARC/INFO® using a combination of digital and

analog sources, and a variety of GIS analysis tools.

The three primary digital sources for the ELUI included: (1) City of Albuquerque Geographic Information System (AGIS) digital land-use data, December 1996; (2) U.S. Department of Interior, Bureau

of Reclamation Land-Use Trend Analysis (LUTA)

data for the years 1992–1993; and (3) digital orthophotography for Bernalillo County acquired in

March and May of 1996. The LUTA data utilized 35

land-use classes of which approximately 20 related

to crop or vegetation cover. The AGIS data used

more than 600 land-use categories. We converted

these two sources to the ELUI classes with correspondence tables. Aerial photography and land-use

maps were used for compilation and updating, using both manual techniques and “heads-up” digitizing. Local government planners, zoning administrators, and rural addressing personnel assisted in

the inventory and review of data. We collected and

verified a limited amount of field data when necessary.

GIS tools assisted in customizing the initial land-use

polygon coverage for input to the LAM. MRGCOG

planners required that major regional centers (employment and/or commercial) be distinguished in

the inventory. Seven regional centers were identified and outlined on land-use plots. Parking areas

within these regional center boundaries were reclassified to conform to their abutting polygon land-use

classes. Subsequently, all polygons of office and

major retail ELUI classes falling outside of regional

center boundaries were changed to the

mixed/minor commercial ELUI class. The polygon

coverage was converted to a raster format using

ARC GRID, and all street and railroad right-of-way

(ROW) cells were recalculated to the ELUI class of a

non-ROW neighbor. We converted this GRID coverage to polygons, and only major street and railroad ROW were added back into the coverage with

buffering and overlay processes in ARC/INFO®.

We added housing and employment densities to

each polygon by ELUI class based on 1996 socioeconomic data for the 668 Data Analysis Subzones in

the region.

Future land-use scenarios and constraint or scoring

layers will be developed using LAM modules. Constraint layers define areas where land use such as

employment or housing would be unlikely or constrained; one example might be slopes greater than

30%. Scoring layers “score” a polygon based on its

desirability for development. The model will then

allocate forecast housing and employment based on

these layers and constrained by regional controls. A

new ArcView® shape file with housing and employment densities is produced from which other

necessary socioeconomic variables can be generated

for input to transportation, air quality or other

models.
DATA PRODUCTION STATUS FOR THE MIDDLE RIO GRANDE BASIN

Laurie Davis

U.S. Geological Survey, Rocky Mountain Mapping Center,

Box 25046, MS 516, Denver, CO 80225

Recent investigations of the Albuquerque basin by

the U.S. Geological Survey (USGS) and federal,

state, and local agencies have determined that the

aquifer system is not as extensive as previously

thought. This finding has resulted in a concerted

effort by federal, state, and local agencies to gather

and interpret additional hydrologic, geologic, and

geographic data to better manage the important

water resources of the Middle Rio Grande Basin.

The USGS established a team to conduct research

required for the next 5 years (FY 1996–2000) and to

coordinate these efforts with federal, state, and local

agencies. One role of the USGS National Mapping

Division (NMD) is to provide base cartographic

data in support of the Middle Rio Grande Basin

study. Currently, the 126-quadrangle project area

has complete coverage for the following products:

(1) 7.5-minute 30-meter digital elevation models

(DEM);

(2) 1:24,000-scale digital line graph (DLG-3) data

for hydrography, cultural features, transportation, the Public Land Survey System, and the

quad boundary;

(3) 1:24,000-scale digital raster graphics (DRG);

and

(4) 1:40,000-scale black-and-white aerial photographs (NAPP).

To identify additional requirements for base cartographic data, a Middle Rio Grande Basin solicitation

package was distributed in January 1997 to more

than 40 federal, state, and local agencies working in

New Mexico. The base cartographic data offered in

the solicitation package were black-and-white, 1-

meter-resolution digital orthophoto quadrangles

(DOQ), 7.5-minute 10-meter DEM, and limited update revision of the DLG-3 categories mentioned

above. Seven responses were returned in February

1997. Three Department of the Interior (DOI) bureaus submitted responses through the DOI HighPriority Digital Base Data Program solicitation.

The purpose of the Middle Rio Grande Basin solicitation was to ensure the most efficient use of available funding and production resources to satisfy

requirements for base cartographic data. NMD

evaluated the responses and developed a selection

process based on two criteria: (1) data requested

needed to be used in support of the Middle Rio

Grande Basin study; and (2) data requests from

multiple agencies must be overlapping. After

evaluating the responses, NMD developed the following base cartographic production plan.

Digital Orthophoto Quads (DOQ)

Through the DOI High-Priority Digital Base Data

Program and USGS internal funding sources, and in

partnership with the U.S. Forest Service, 119 quadrangles (476 quarter-quadrangles) are authorized for

DOQ production. Digital orthophoto quads will be

produced using the 1996 NAPP photographs for all

quadrangles except: Mesa Sarca, Comanche Ranch,

Mountainair, Willard, Ladron Peak, Mesa Draw,

and Round Top. Scheduled completion date is

January 1999.

Digital Elevation Models (DEM)

The entire 126-quadrangle project area is currently

authorized for 10-meter DEM production. Scheduled completion date is March 1998.

Digital Line Graphs (DLG-3)

Seventy-five 1:24,000-scale quadrangles are currently authorized for DLG-3 hypsography collection

to provide complete contour coverage for the project area. Scheduled completion date is March 1998.

Limited update revision of DLG-3 data files

Evaluation of the Middle Rio Grande Basin solicitation responses identified eighty 1:24,000-scale quadrangles where limited update revision of DLG-3

data files was requested. The NMD team photoinspected 14 of those quadrangles to determine

which DLG-3 overlays would require digital limited-update (DLU) revision. Photo-inspection

showed that four quadrangles required no DLU

revision, four quadrangles required transportation

revision, and six quadrangles required DLU revision for both transportation and cultural features.

NMD will do the DLU revision for these 1:24,000-

scale DLG-3 overlays in fiscal year 1998. NMD has

yet to resolve how the remaining 66-quadrangle
DLU requirement will be met during fiscal year

1998.

File transfer protocol (ftp) will be used to distribute

data in response to each solicitation except for DOQ,

which will be distributed on 8-mm tape.

DESIGN AND DEVELOPMENT OF

THE MIDDLE RIO GRANDE BASIN STUDY WEB PAGES

Mark R. Feller

U.S. Geological Survey, Rocky Mountain Mapping Center,

Box 25046, MS 516, Denver, CO 80225

The Middle Rio Grande Basin (MRGB) study web

site enables those involved with the project to disseminate information about the hydrology, geology,

and land-surface characteristics of the region. The

web site is a centralized location, accessed via the

Internet, where study results are readily available.

The software tools used to develop the individual

pages included various software packages for webpage publishing, multiple search engines to locate

appropriate links to relevant sites, an interactive

image display and editing tool for an X Windowing

system, and the Gnu Emacs editor with multiple

ELISP (emacs interpreted programming language)

macros. Various browsers were used for testing the

look and feel of the individual web pages developed. The browsers used during the testing phase

were Internet Explorer version 2.0, Internet Explorer

version 3.02, Netscape Navigator 2.0, Netscape

Navigator 3.01 Gold, Netscape Communicator 4.02,

Mosaic version 2.4, and Mosaic version 2.7. The

hardware used in developing and testing the software consisted of personal computers, Data General workstations and servers, and a Howtek scanner. The server that hosts the Middle Rio Grande

Basin web pages is a Data General Aviion 6240.

This machine has four 22 megahertz processors with

96 megabytes of RAM (random access memory),

along with 8 gigabytes of storage. The version of

the software used for making hypertext and other

documents available to web browsers is NCSA’s

HTTPD version 1.5. The server that hosts the pages

is located at the U.S. Geological Survey (USGS),

Rocky Mountain Mapping Center (RMMC) in Denver, Colorado. (Any use of trade, product, or firm

names is for descriptive purposes only and does not

imply endorsement by the U.S. Government.)

The guidelines followed for the general layout of

the web pages are published in the document USGS

Data and Publications on the Internet World Wide Web.

This document was approved by all areas within

the USGS that develop web pages. The page design

for the Middle Rio Grande Basin study uses frames

that allow individual areas within a page viewed on

a screen to take on their own characteristics. One of

the main goals for the Middle Rio Grande Basin web

site was to provide the capability for anyone to access the information on the web site, whether the

user’s browser supported frames or not. Therefore,

parallel development was required, allowing both

the browsers that did not have frame functionality

and those that did to view the same content of the

web pages. Each web page was developed to allow

the user to return to the Middle Rio Grande Basin

home page and to send any comments, criticism, or

information to the USGS Middle Rio Grande Basin

study project manager. When the general presentation of the web pages was being considered, multiple browsers with multiple hardware configurations

were taken into account.

The base content used for the web pages was the

Middle Rio Grande Basin Study Fact Sheet FS-034

published in March 1997. There are nine main information pages under the home page. Each of the

nine pages concerns a question discussed in the fact

sheet. Each of these main pages can be reached at

any time by clicking on the appropriate button on

the left side of the web page. Other information

linked to the web pages gives the user the option to

view documents that support the fact sheet.

For example, an electronic copy of the publication,

Simulation of Ground-Water flow in the Albuquerque

Basin, central New Mexico, 1901–1994, with Projections
to 2020 (USGS Water-Resources Investigations Report 94-4251), can be viewed from the web pages.

This publication discusses why the study is necessary, describes how the results of these projects will

be used, and shows references cited. From the References Cited web page the user can retrieve an

electronic copy of USGS MRGB Study--Proceedings of

the First Annual Workshop (USGS Open File Report

97-116), and the publication, Plan of Study to Quantify the Hydrologic Relations between the Rio Grande

and the Santa Fe Group Aquifer System near Albuquerque, central New Mexico (USGS WRIR 96-4006). The

web page links to other governmental agencies involved in studying the water resources in the basin.

These include: City of Albuquerque, New Mexico

Office of the State Engineer, New Mexico Bureau of

Mines and Mineral Resources, Bureau of Reclamation, several Pueblos within the study area, Bernalillo County, New Mexico Environment Department, Sandia National Laboratories, Los Alamos

National Laboratory, U.S. Environmental Protection

Agency, U.S. Army Corps of Engineers, and Middle

Rio Grande Basin Technical Advisory Committee.

From the web page that contains facts on what projects will be completed under the study, the user can

access the home pages of three divisions within the

USGS, along with links to the digital line graph

(DLG), digital elevation model (DEM), and digital

orthophoto quadrangle (DOQ) programs. From this

same page the user can also visit the New Mexico

Resource Geographic Information System Program

and the U.S. Geological Survey’s airborne geophysical surveys web sites. Graphics files explaining the

status of geologic mapping in the basin are also

available from the web page that discusses which

projects will be completed under the Middle Rio

Grande Basin study. Within the web page that

contains sources of additional information are links

to the New Mexico Water Resources District Chief

for water information, the RMMC chief for mapping

information, and the USGS Central Regional geologist for geologic information, along with the USGS

Middle Rio Grande Basin study Coordinating

Committee and Technical Advisory Committee.

There are many opportunities for development

within the web site. For example, animated graphic

image format files could be used to display historical data compiled in the study or possibly to show

forecasts of model results. Movies, such as Aquifer

Dynamics of the Middle Rio Grande Basin, could also

reside on the web pages. Presentations and demonstrations could be recorded and put on the web for

viewing. There are plans to incorporate image maps

that will allow the user to click on a 1:24,000-scale

quadrangle within the Middle Rio Grande Basin

study area. Different types of information, such as

DLG and DEM data availability, horizontal and

vertical datums used for the USGS basecartographic data products, and vintage USGS

1:24,000-scale topographic maps within the basin,

could then be accessed. The Internet efficiently disseminates information to the public, and the USGS

is taking advantage of this form of electronic media

to keep the public informed about the Middle Rio

Grande Basin study.
ADMINISTRATIVE PAPERS

NEW MEXICO’S STATEMAP PROGRAM:

GEOLOGIC QUADRANGLE MAPPING

ALONG THE RIO GRANDE WATERSHED

Paul Bauer

New Mexico Bureau of Mines and Mineral Resources,

801 Leroy Place, Socorro, NM 87801

<bauer@nmt.edu>

During the first five years of the New Mexico Bureau of Mines and Minerals Resources (NMBMMR)

STATEMAP program, we will have mapped 26 7.5-

minute quadrangles along the Rio Grande urban

corridor between Taos and Belen (Fig. 17). In June

of 1998, we begin work on 10 more quadrangles.

The final products are digital, detailed geologic

maps (1:24,000 and 1:12,000), with accompanying

unit descriptions, cross sections, stratigraphic sections, and explanatory texts. Each quadrangle emphasizes bedrock lithology and structure, and surficial-basin and arroyo-valley deposits, and their importance to ground-water resources and land-use

planning. Due to the geologic complexity of the

mountain-front areas, we use a multidisciplinary

approach to mapping, which utilizes specialists for

various aspects of the project, including geoscientists from the NMBMMR, New Mexico Tech, University of New Mexico, and the private sector.

These quadrangles were selected based on their

potential to provide high-quality earth-science data

to potential users. The Rio Grande corridor is of

vital economic, social, and scientific welfare to the

state. The important societal needs that we have

identified along the Rio Grande watershed are:

(1) Environmental—(a) ground-water and surfacewater supply, availability, and quality; (b) geologic hazards such as flooding, hydrocompaction, and slope stability;

(2) Earth resources—metallic minerals, industrial

minerals, aggregate, rock resources;

(3) Land-use planning—landform dynamics, soil

properties, water rights, etc.; and

(4) Transportation.

A combination of rapid population growth, permeable alluvial aquifers, large topographic relief, and

the alternating scarcity and abundance of meteoric

Fiscal

year

STATEMAP $

available

NMBMMR

$ awarded

% of

total Quad(s) mapped Average$/quad

1993-4 $1,442,734 $20,000 1.4 Tijeras $20,000

1994-5 $1,979,641 $50,000 2.5 Albuquerque East, Sandia Crest, Placitas $16,667

1995-6 $1,287,000 $50,000 3.9 Sandia Park, Hubbell Spring, McClure

Reservoir

$16,667

1996-7 $4,376,400 $165,330 3.8 Isleta, Alameda, Mt. Washington, Sky

Village SE, Jemez Pueblo, Santo Domingo Pueblo, Glorieta, Taos SW

$23,619

1997-8 $3,708,814 $157,421 4.2 Bernalillo, Albuquerque West, San Ysidro, San Felipe Pueblo, Sedillo, Dalies,

Carson, Seton Village, Bosque Peak,

Loma Creston, Santo Domingo Pueblo

SW

$17,491

1998-9 $3,762,798 $150,000 4.0 San Pedro, Edgewood, San Felipe Pueblo

NE, Galisteo, Santa Fe, Veguita, Socorro,

Ranchos de Taos, Rosilla Peak, Capilla

Peak

$15,000
Figure 17. Index map of 7.5-minute quadrangles in the Rio

Grande watershed showing New Mexico Bureau of Mines

and Mineral Resources STATEMAP quadrangles in progress

(1998–1999) and (1997–1998), and completed (1994–1997).
water gives rise to a host of hydrogeologic and engineering geologic problems. The Albuquerque,

Española, San Luis, and Socorro basins and adjacent

uplifts have become the focus of geologic and hydrologic interest by local, state, tribal, and federal

officials due to concern over the supply of ground

water for an expanding population. Understanding

watersheds and basin-fill stratigraphy is critical to

ensure potable water for the future, and to mitigate

aquifer contamination. Surficial deposits provide

critical data on flood-prone zones, areas subject to

mass wasting, and soil and sediment parameters

that influence construction plans and land management. Geologic structures also control groundwater flow; in particular, the hydrogeologic significance of both rift-related normal faults and transverse fault zones needs quantifying. Several of the

quadrangles also contain rocks (Proterozoic to Cenozoic in age) that are the focus of topical, ongoing

investigations in rock and mineral resources, structural geology, stratigraphy and sedimentology, basin evolution, and tectonics. Furthermore, the maps

will benefit government bodies (state, county, tribal,

local) and private organizations (environmental,

planners, developers, citizens groups). The

NMBMMR has actively cultivated working relationships with such groups, all of which have expressed

a need for detailed geologic maps. The NMBMMR

and the State Geologic Mapping Advisory Board,

which consists of 30 members from federal, state,

county, municipal, tribal, and private agencies, are

responsible for setting mapping priorities in New

Mexico.

The overall project objective is to characterize the

geology of each area in sufficient detail to allow use

of this information in matters of practical economic

and environmental concern to governments, communities, and planners, as well as to satisfy the fundamental goals of basic science. In addition, we will

continue to integrate information from individual

quads into an ever-expanding regional synthesis of

stratigraphy, structure, hydrogeology, and engineering geology. This multidisciplinary approach

to mapping and subsurface investigations in one of

the most rapidly growing regions in the southwestern U.S. will serve the multiple goals (social, economic, scientific) of the National Geologic Mapping

Program and the people of New Mexico.

We work closely with USGS–Geologic Division personnel involved in the Middle Rio Grande Basin

Project, and expect most of our maps will be used in

the USGS 1:100,000 compilation of the Albuquerque

Basin. Several of our quads dovetail with EDMAP

projects sponsored by professors at New Mexico

Tech and UNM. Some of our quads compliment

cooperative investigations, such as ongoing hydrogeologic studies with the Office of the State Engineer and Sandoval County.

Our STATEMAP geologic maps have significantly

increased our understanding of the bedrock geology, surficial deposits, hydrogeology, and subsurface stratigraphy and structure of the Rio Grande

rift basins and uplifts. Agency personnel who address environmental, water-resource, and landplanning issues value our maps.
NEW MEXICO DISTRICT COOPERATIVE PROGRAM

IN THE MIDDLE RIO GRANDE BASIN, FY98

Dennis G. Woodward

U.S. Geological Survey, Water Resources Division,

4501 Indian School Road, N.E., Suite 200, Albuquerque, NM 87110

The New Mexico District of the U.S. Geological Survey (USGS) has established and fostered for many

decades a dynamic Federal-State Cooperative Program in the Middle Rio Grande Basin, central New

Mexico. In the Cooperative Program, investigative

projects and data-collection activities are jointly

identified, planned, and funded by the USGS (as

much as 50 percent) and by State and local agencies.

Generally, the State and local agencies provide at

least one-half the funds, and the USGS does most of

the work. The collective results of the Cooperative

Program have provided the scientific basis and the

institutional framework for developing the USGS

Middle Rio Grande Basin Study that began in fiscal

year 1996. This article briefly describes the historical highlights of the Cooperative Program in the

Middle Rio Grande Basin and the components of

the present program. Of the approximate $4.5 million allocated in fiscal year 1998 for USGS work in

the basin, about $1.6 million was from the Cooperative Program. The major agencies in the Cooperative Program in the basin study are the City of Albuquerque (City), the New Mexico Office of the

State Engineer Office (NMOSE), and Bernalillo

County.

One of the earliest highlights of the Cooperative

Program in the Middle Rio Grande Basin was the

report on the availability of ground water in the

Albuquerque area by Bjorklund and Maxwell

(1961). They presented regional maps of the geology and water-table configuration in the area.

Reeder and others (1967) provided a quantitative

analysis of the water resources in the Albuquerque

area, with computed effects on the Rio Grande from

ground-water pumpage. They presented projected

water-table declines and depletions of Rio Grande

flow due to projected ground-water withdrawals.

Following a period primarily devoted to datacollection activities, the development, construction,

and documentation of the Albuquerque Basin

ground-water-flow model rank as a recent significant milestone in the Cooperative Program with the

City of Albuquerque. Thorn and others (1993) described the geohydrologic framework and hydrologic conditions used in the flow model, and Kernodle and others (1995) presented the results of the

flow model. McAda (1996) detailed a plan of study

to quantify the hydrologic relations between the Rio

Grande and the Santa Fe Group aquifer system in

the Albuquerque area; 13 essential activities and

informational needs were identified and prioritized.

The most recent highlight of the Cooperative Program with the City is the drilling and completion of

a series of nested piezometers located throughout

the Albuquerque area. By the end of calendar year

1997, 11 piezometer nests—each with three piezometers—were completed at nine different sites.

Generally, the nests have piezometers that measure

water levels near the water table, near the middle of

the “production zone” in the City wells, and near

the base of the “production zone” in the City wells.

The current (1998) Cooperative Program with the

City contains the following components: (1) continuation of the ground-water-level monitoring

network; (2) expansion of the monitoring network

by completion of more nested piezometers; (3) estimation of surface-water depletions from the Rio

Grande resulting from ground-water withdrawals—

results from model simulations will be compared to

results from the Glover-Balmer (1954) method; (4)

estimation of seepage rates from the Rio Grande,

canals, and drains in the Albuquerque area; (5)

monitoring of low-flow conditions in urban storm

drains; (6) Rio Grande flood-pulse investigation; (7)

determination of mountain-front recharge by chloride-balance methods; (8) assessment of waterquality trends in City production wells; (9) dissemination of hydrologic information over the Internet:

(10) update of the regional ground-water-flow

model; (11) assistance to the Upper Rio Grande

Water Operations Model; and (12) investigation of

aquifer compaction and land subsidence. Many of

these activities focus on quantifying hydrologic relations between the Rio Grande and the aquifer

system, as identified in the McAda (1996) plan. The

current (1998) Cooperative Program with the

NMOSE contains the following components: (1)

revision of the Albuquerque Basin ground-waterflow model; (2) participation in the estimation of

physical and hydraulic characteristics of canals and
drains; (3) participation in the drilling and completion of the nested piezometers network; (4) participation in a large-scale aquifer test in Albuquerque;

and (5) continuation of the long-term ground-waterlevel monitoring network. The 1998 Cooperative

Program with Bernalillo County provides for the

drilling and completion of a series of deep-nested

piezometers.

REFERENCES

Bjorklund, L.J., and Maxwell, B.W., 1961, Availability of ground water in the Albuquerque area, Bernalillo and Sandoval Counties, New Mexico: New Mexico State Engineer Technical Report 21, 117 p.

Glover, R.G., and Balmer, G.G., 1954, River depletions resulting from pumping a well near a river: EOS, Transactions,

American Geophysical Union, v. 35, no. 3, p. 468-470.

Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020: U.S. Geological Survey Water-Resources Investigations

Report 94-4251, 114 p., 1 pl.

McAda, D.P., 1996, Plan of study to quantify the hydrologic relations between the Rio Grande and the Santa Fe Group

aquifer system near Albuquerque, central New Mexico: U.S. Geological Survey Water-Resources Investigations

Report 96-4006, 58 p.

Reeder, H.O., Bjorklund, L.J., and Dinwiddie, G.A., 1967, Quantitative analysis of water resources in the Albuquerque

area, New Mexico—Computed effects on the Rio Grande of pumpage of ground water, 1960-2000: New Mexico

State Engineer Technical Report 33, 34 p.

Thorn, C.R., McAda, D.P., and Kernodle, J.M., 1993, Geohydrologic framework and hydrologic conditions in the Albuquerque Basin, central New Mexico: U.S. Geological Survey Water-Resources Investigations Report 93-4149, 106

p.

MEMORANDUM OF UNDERSTANDING BETWEEN

THE U.S. GEOLOGICAL SURVEY – NATIONAL MAPPING DIVISION AND

THE MIDDLE RIO GRANDE COUNCIL OF GOVERNMENTS OF NEW MEXICO

Lee W. Aggers1, Stephen J. Burstein2, and David J. Hester1

1

U.S. Geological Survey, Rocky Mountain Mapping Center,

Box 25046, MS 516, Denver, CO 80225 2

Middle Rio Grande Council of Governments,

317 Commercial, N.E., Suite 300, Albuquerque, NM 87102

This Memorandum of Understanding (MOU) between the U.S. Geological Survey (USGS), National

Mapping Division (NMD), and the Middle Rio

Grande Council of Governments (MRGCOG) of

New Mexico was signed on June 18, 1997. An official copy of the signed MOU may be requested from

either individual listed under the “Points of Contact” section. Due to abstract limitations, the following summary has omitted the definitions, implementation plan, superseded agreements, and

approval sections from the original signed MOU.

Purpose

This MOU is established between the USGS, NMD,

and the MRGCOG (known as the partner agency) to

provide the capability to share various geographic

data, and to foster mutual land-use modeling applications. This MOU will facilitate the transfer of

technology, the exchange of digital and hardcopy

geographic data, and the joint development of

methods for land use analysis.

Objectives

1. To promote a shared cooperative partnership

that will mutually benefit both agencies participating in joint land-use/land-cover and landsurface characterization research and development.

2. To provide a mechanism for coordination, production, and exchange of analog mapping

products, digital cartographic data, and re-
motely sensed data to be used by the MRGCOG

and the USGS for land-use analysis.

3. To exchange geospatial data, geoprocessing

technologies, and modeling methods for landsurface analysis research.

4. To mutually enhance the ability to transfer

products and technology, and to support the

use and application of geospatial data for landuse modeling.

Background

USGS

As the principal national mapping agency of the

United States, one of the missions of the USGS is to

produce, update, and disseminate geographic, cartographic, remotely sensed, and related earthscience information in graphic and digital form.

The USGS is involved in the Middle Rio Grande

Basin (MRGB) Study, which is a cooperative

interdivisional and interagency effort to improve

quantitative understanding of water availability in

the Albuquerque-Santa Fe urban corridor. The objective of the study is to provide critical earthscience information and analysis tools to help municipal officials with future land-use and waterresources planning.

The role of NMD in the MRGB Study consists of

producing base cartographic data in the project

area, working with cooperating agencies to characterize the land surface, and creating the infrastructure for management of MRGB geospatial data.

Since the MRGCOG is developing a land-use analysis model (LAM) for its area of interest (covers approximately 90 percent of the MRGB Study), the

USGS is interested in cooperating with the

MRGCOG as the model is developed. This effort

will assist the USGS in future work with cooperators interested in land-surface characterization.

MRGCOG

The MRGCOG is a voluntary association of counties, municipalities, and other local governments

and organizations in State Planning and Development District 3. As a planning organization, the

MRGCOG directs various programs of regional

systems planning and gives technical assistance to

member organizations.

The MRGCOG has recognized the need for a regional land use plan. The goal of the plan is to produce a long-range strategy for managing growth in

the region during the next 50 years. Therefore, the

MRGCOG has contracted for the production of detailed visualization studies of urban design and rural character as support documents for the Focus

2050 Regional Plan. Because of the USGS’s interest

in modeling land use, the MRCGOG will work cooperatively with the USGS as the LAM is developed.

Scope

This Memorandum of Understanding is an agreement between the USGS and the MRGCOG that sets

forth basic policies and procedures governing matters of mutual interest and responsibility. Under

this agreement, activities include, but are not limited to, base cartographic data collection (such as

cost-share, work-share, or data-exchange), regional

plan and (or) land-surface characterization database development, participation on regional landuse committees, technical assistance in deriving

land-use data, and training for land-use analysis

software. This agreement covers production and

exchange of geospatial data, technical assistance for

land-use analysis, joint development and exchange

of land-use analysis software, and review of landuse and land-cover classification standards.

Authorities and Policies

This agreement is entered into under the following

authority:

1. Authorizing Legislation of the USGS (P.L. 100,

March 7, 1928), which directs that the Geological Survey’s share in any topographic mapping

or water-resources investigations carried out in

cooperation with any state or municipality shall

not exceed 50 percent of that cost (43 U.S.C.50).

2. Department of the Interior USGS manual

(500.1.1), which establishes the policy of the

USGS in cooperative work with states, counties,

municipalities, and other political subdivisions.

3. OMB Circular A-16, and Presidential Executive

Order 12906, April 11, 1994, Coordinating Geographic Data Acquisition and Access: The National Spatial Data Infrastructure (NSDI).

4. Articles of Agreement establishing the Middle

Rio Grande Council of Governments executed

December 11, 1969, with amendments through

December 12, 1996.

5. In case of conflict, the appropriate Federal laws

and regulations apply.

Responsibilities

Specific activities and responsibilities that may be

undertaken as part of this agreement are as follows:
The USGS will:

1. Participate in the MRGCOG LAM design requirements meetings when requested by the

MRGCOG.

2. Participate on the MRG Regional Land Use

Task Force when requested by the MRGCOG.

3. Participate on the MRGCOG LAM User Acceptance Team when requested by the

MRGCOG.

4. Provide 1996 National Aerial Photography

Program (NAPP) photographic products, including 1:12,000-scale digital orthophoto quadrangles (DOQ), for specific areas requested by

the MRGCOG.

5. Provide the MRGCOG assistance in deriving

their land use category for constrained lands or

provide the MRGCOG with the raw digital

elevation model (DEM) data necessary to derive the land use category.

6. Invite the MRGCOG to attend any USGS

workshop regarding landscape change analysis, human-induced land transformations,

land-use modeling, or urban dynamics.

The MRGCOG will:

1. Assist the USGS with land use and land cover

(LULC) verification during the LULC data

compilation activity.

2. Provide converted U.S. Bureau of Reclamation

and City of Albuquerque LULC digital data as

well as any supporting analog land-use maps

for use by the USGS in compiling LULC data.

3. Provide information regarding the attractiveness scores used to code land-use polygons for

different development scenarios as well as information regarding the LAM system architecture.

4. To the maximum extent possible, provide the

USGS with courtesy copies of the adopted

plans, sector plans, and comprehensive plans

for all cities and counties within the MRGB

land-surface analysis pilot area.

5. Provide (on an as-needed basis) input to the

USGS’s land-surface analysis, urban dynamics,

and land-cover characterization program requirements.

The USGS-NMD, and the MRGCOG will:

1. Exchange digital and (or) analog information

(i.e., contemporary and historical) required for

either the USGS MRGB Land-Surface Analysis

activity or the MRGCOG LAM.

2. Participate in jointly reviewing the Land-Based

Classification Standards Project sponsored by

the American Planning Association.

3. Exchange the LAM software and the USGS Urban Growth Model software as well as any output-development scenario data-sets for analyzing differences in model results.

4. Exchange 1:100,000-scale and 1:24,000-scale

digital raster graphics (DRG) in support of the

MRGCOG Focus 2050 Regional Plan and USGS

MRGB Study.

5. Exchange LULC classification schemas being

implemented for the USGS MRGB study and

the MRGCOG regional plan.

Financial Arrangements

Funding

When it becomes necessary that both agencies must

exchange funds, then an annex will be prepared to

this agreement that cites the existing agreement, the

need for funds to be exchanged, funding amount,

products and (or) services to be rendered, etc. Both

agencies will sign and date the annex. The agreement to exchange funds will not take effect until

both parties have signed the annex.

Constraints

Cost sharing by the USGS-NMD cannot exceed 50

percent of the cooperative project costs.

Coverage

The amount contributed covers all the necessary

field and office work directly related to the program, but excludes any bureau-level general administrative or accounting work.

Period of Agreement

Effective Agreement

This agreement shall be in effect from the date of the

last signature until the USGS MRGB Study and

MRGCOG Focus 2050 Regional Plan are complete.

Review Cycle

This agreement will be reviewed every 6 months, or

at the request of either agency, for possible modification, as appropriate.

Modifying or Terminating Clause

This agreement may be modified at any time upon

joint approval, or may be terminated by either

agency upon 90 days written notice, or at any time

by mutual consent.
Points of Contact

Both the USGS and the MRGCOG will designate

one individual to serve as the contact for the resolution of technical and production-related questions.

David J. Hester

USGS-National Mapping Division

Box 25046, MS 516

Denver, CO 80225-0046

Tel: (303) 202-4318

Fax: (303) 202-4354

E-mail: dhester@usgs.gov

Stephen J. Burstein

MRGCOG

317 Commercial N.E., Suite 300

Albuquerque, NM 87102-3429

Tel: (505) 247-1750

Fax: (505) 247-1753

E-mail: sburstein@mrgcog.org

OVERVIEW OF THE FOCUS 2050 REGIONAL PLAN

Dennis R. Foltz, AICP (American Institute of Certified Planners), and Stephen Burstein, AICP

Middle Rio Grande Council of Governments

317 Commercial, N.E., Suite 300, Albuquerque, NM 87102

The Middle Rio Grande Council of Governments

(MRGCOG) has initiated a project called the Focus

2050 Regional Plan, which aims to create a longrange vision and strategy for managing growth and

development within the Middle Rio Grande Basin.

Economic sustainability is the goal. The year

through which the Plan applies is 2050. The Focus

2050 Regional Plan area comprises Bernalillo, Sandoval, Torrance, Valencia and southern Santa Fe

Counties (Fig. 18).

Plan development is scheduled for approximately

four years, and consists of eight overlapping activities (Fig. 19). During this second year of Focus 2050,

the following components have been accomplished

or are in progress: (1) socioeconomic projections to

the year 2050; (2) existing-conditions report; (3) existing land-use inventory; (4) urban design/rural

character study; (5) completion of the Regional Vision Statement and Goals; (6) development of the

Land-Use Analysis Model (LAM); and (7) coordination on regional water planning including the Middle Rio Grande Water Assembly. The Regional

Land-Use Task Force, a technical committee made

up of MRGCOG appointees, is assisting in developing Focus 2050. Thus far two subcommittees

have been formed and are conducting regular

meetings: the Linked Regional Open-Space Task

Group and the Land-Use Alternatives Subcommittee. Additional subcommittees will be formed

during the next year. The Executive Board of

MRGCOG, consisting of local government-elected

officials, serves as the policy-development board for

Focus 2050.

Coordination between MRGCOG and the U.S.

Geological Survey (USGS) – National Mapping Division has been helpful to the development of Focus

2050 in numerous ways including: (1) assistance in

designing the specifications for LAM; (2) acquisition

of selected digital orthophoto data for inventorying

existing land-use; and (3) use of slope analysis as a

layer of “constrained land” for LAM. In turn,

MRGCOG has provided the USGS with products of

our study that should assist the Middle Rio Grande

Basin Study. Among these are: Existing Land-Use

Inventory, Land-Use Analysis Model (LAM), and

concept scenarios.

Results-to-date of two of the most important activities of Focus 2050 are outlined below. Both Public

Involvement and Land-Use Scenarios synthesize

information from the other activities.

Public Involvement

We conducted the Focus 2050 Regional Visioning

process from August 1997 through January 1998.

More than 400 participants worked to develop the

Vision Statement and Goals through: (1) sets of

workshops in each County served by MRGCOG; (2)

community interviews; and (3) facilitated discus-
sions with planning commissions, local elected

bodies and others concerned with long-range development. The MRGCOG Board of Directors

adopted the Statement and Goals on January 8, 1998

to guide the Focus 2050 Regional Plan. Future public-involvement events scheduled are the Educational Symposium to coincide with the “long list” of

alternative land-use scenarios and the Regionalism

Town Hall for public involvement in selecting the

preferred land-use alternative.

Land-Use Scenarios

The Land-Use Analysis Model (LAM) GIS application will be used to draw the alternative land-use

scenarios, depict the socioeconomic factors corresponding with land-use change, and allocate the

land use and socioeconomic changes based on

scoring principles. Transportation, air quality, water, economic development, linked regional openspace, housing and utilities are factors that will influence land-use scenarios in Focus 2050 (Fig. 20).

The Land-Use Alternatives Subcommittee, consisting of people from cross-disciplinary public and

private backgrounds, is currently working on the

assumptions and principles that will be depicted in

the “long list” of alternative land-use scenarios. This

subcommittee will report to the Regional Land-Use

Figure 18. Map showing the Focus 2050 Regional Plan area.
Task Force, which will make recommendations to

the Executive Board of MRGCOG throughout the

process. A short list of three or four scenarios will

be considered for further evaluation. The preferred

alternative may be a combination of some of the

best features of several scenarios.

Many groups will use the Focus 2050 Regional Plan;

among them are: governmental agencies, non-profit

agencies, and businesses and private citizens committed to involvement in regional issues. Local

governments may use the plan as a “template” to

guide local comprehensive plans. Focus 2050 will

be used to guide MRGCOG in such areas as transportation planning, regional water planning, and

growth-management technical assistance. The preferred long-use scenario in Focus 2050 will be integrated into the Middle Rio Grande Long-Range

Major Transportation Improvement Study being

developed by MRGCOG for the Metropolitan Planning Organization.

In conclusion, Focus 2050 links cross-functional

planning among multiple jurisdictions in the region.

The adoption and implementation of the Regional

Plan by local governments will be a meaningful step

toward a regional planning effort. Opportunities

for collaboration between the MRGCOG and the

local government members of the Council of Governments, state agencies, and federal agencies exist

within the framework of the Focus 2050 Regional

Plan.

Figure 19. Timeline showing activities scheduled for the Focus 2050 Regional Plan process.

Figure 20. Sketch showing functional plan areas related

to the Focus 2050 Regional Plan.
MIDDLE RIO GRANDE BASIN STUDY

PARTICIPATING ORGANIZATIONS

U.S. Geological Survey – Geologic Division

National Cooperative Geologic Mapping Program

P.O. Box 25046, MS 913

Denver, CO 80225

U.S. Geological Survey – Water Resources Division

New Mexico District Office

4501 Indian School Road, N.E.

Albuquerque, NM 87110

U.S. Geological Survey – National Mapping Division

Rocky Mountain Mapping Center

P.O. Box 25046, MS 516

Denver, CO 80225

New Mexico Bureau of Mines and Mineral Resources

801 Leroy Place

Socorro, NM 87801

City of Albuquerque

Public Works Department

Water Resources Management

P.O. Box 1293

Albuquerque, NM 87103

New Mexico Office of the State Engineer

P.O. Box 25102

Santa Fe, NM 87504

Middle Rio Grande Council of Governments

317 Commercial Ave., N.E., Suite 300

Albuquerque, NM 87102

University of New Mexico

Department of Earth and Planetary Sciences

Albuquerque, NM 87131

New Mexico Institute of Mining and Technology

Earth and Environmental Science Department

Socorro, NM 87801

Front cover:

Geologic map of the Middle Rio Grande Basin Study area.

Geology clipped and reduced from Geologic Map of New Mexico.

Compiled by O.J. Anderson, G.E. Jones, and G.N. Green, 1997.

Digital database by G.N. Green and G.E. Jones.

Back cover:

Configuration of hydrogeologic units (subsurface representation 1)

in the ground-water flow model of the Middle Rio Grande Basin

(see Tiedeman, p. 11-13, this volume).