Hydrogeologic Terranes and Potential Yield of Water to

Wells in the Valley and Ridge Physiographic Province

in the Eastern and Southeastern United States

r

iUSGS

tnce for a changing world
AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY

Instructions on ordering publications of the U.S. Geological Survey, along with prices of the last offerings, are given in the currentyear issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey publications released prior to the current year are listed in the most recent annual "Price and Availability List." Publications that may be listed in 

various U.S. Geological Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" may 

be no longer available.

Order U.S. Geological Survey publications by mail or over the counter from the offices given below.

BY MAIL OVER THE COUNTER

Books

Professional Papers, Bulletins, Water-Supply Papers, Techniques of Water-Resources Investigations, Circulars, publications 

of general interest (such as leaflets, pamphlets, booklets), single 

copies of Preliminary Determination of Epicenters, and some miscellaneous reports, including some of the foregoing series that 

have gone out of print at the Superintendent of Documents, are 

obtainable by mail from

U.S. Geological Survey, Information Services 

Box 25286, Federal Center, Denver, CO 80225

Subscriptions to Preliminary Determination of Epicenters 

can be obtained ONLY from the

Superintendent of Documents

Government Printing Office

Washington, DC 20402

(Check or money order must be payable to Superintendent of 

Documents.)

Maps

For maps, address mail orders to

U.S. Geological Survey, Information Services 

Box 25286, Federal Center, Denver, CO 80225

Books and Maps

Books and maps of the U.S. Geological Survey are available 

over the counter at the following U.S. Geological Survey Earth 

Science Information Centers (ESIC's), all of which are authorized 

agents of the Superintendent of Documents:

 ANCHORAGE, Alaska Rm. 101, 4230 University Dr.

 LAKEWOOD, Colorado Federal Center, Bldg. 810

 MENLO PARK, California Bldg. 3, Rm. 3128, 345 

Middlefield Rd.

 RESIGN, Virginia USGS National Center, Rm. 1C402, 

12201 Sunrise Valley Dr.

 SALT LAKE CITY, Utah Federal Bldg., Rm. 8105, 125 

South State St.

 SPOKANE, Washington U.S. Post Office Bldg., Rm. 135, 

West 904 Riverside Ave.

 WASHINGTON, D.C. Main Interior Bldg., Rm. 2650,18th 

and C Sts., NW.

Maps Only

Maps may be purchased over the counter at the following 

U.S. Geological Survey office:

 ROLLA, Missouri 1400 Independence Rd.
Hydrogeologic Terranes and Potential Yield of Water to 

Wells in the Valley and Ridge Physiographic Province in 

the Eastern and Southeastern United States

By E.F. HOLLYDAY and G.E. HILEMAN

REGIONAL AQUIFER-SYSTEM ANALYSIS 

APPALACHIAN VALLEY AND PIEDMONT

U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1422-C
U.S. DEPARTMENT OF THE INTERIOR 

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY 

Gordon P. Eaton, Director

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. Government.

Library of Congress Cataloging in Publication Data

Hollyday, E.F.

Hydrogeologic terranes and potential yield of water to wells in the Valley and Ridge physiographic province in the eastern and southeastern United States / by E.F. Hollyday and G.E. Hileman.

p. cm. (Regional aquifer-system analysis Appalachian Valley and Piedmont ; C) (U.S. Geological Survey professional paper ; 

1422)

Includes bibliographical references (p. - ).

1. Aquifers Appalachian Basin. 2. Groundwater Appalachian Basin. I. Hileman, G.E. (Gregg Edward), 1962- . II. Title. 

III. Series. IV. Series: U.S. Geological Survey professional paper ; 1422. 

GB1199.3.A6H65 1996

553.7'9'0974 DC21 96-49996

OP 

ISBN 0-607-87064-8

For sale by U.S. Geological Survey, Information Services 

Box 25286, Federal Center, Denver, CO 80225
FOREWORD

THE REGIONAL AQUIFER-SYSTEM ANALYSIS PROGRAM

The RASA Program represents a systematic effort to study a number of 

the Nation's most important aquifer systems, which, in aggregate, underlie 

much of the country and which represent an important component of the 

Nation's total water supply. In general, the boundaries of these studies are 

identified by the hydrologic extent of each system and, accordingly, transcend the political subdivisions to which investigations have often arbitrarily been limited in the past. The broad objective for each study is to 

assemble geologic, hydrologic, and geochemical information, to analyze and 

develop an understanding of the system, and to develop predictive capabilities that will contribute to the effective management of the system. The use 

of computer simulation is an important element of the RASA studies to 

develop an understanding of the natural, undisturbed hydrologic system 

and the changes brought about in it by human activities and to provide a 

means of predicting the regional effects of future pumping or other stresses. 

The final interpretive results of the RASA Program are presented in a 

series of U.S. Geological Survey Professional Papers that describe the 

geology, hydrology, and geochemistry of each regional aquifer system. Each 

study within the RASA Program is assigned a single Professional Paper 

number beginning with Professional Paper 1400.

Gordon P. Eaton 

Director

CONTENTS

Page

Foreword..................................................................................................... iii

Abstract........................................................................................................ Cl

Introduction................................................................................................ 1

Problem................................................................................................ 1

Purpose and Scope.............................................................................. 2

Previous Investigations...................................................................... 3

Acknowledgments.............................................................................. 3

Hydrogeologic Setting............................................................................... 3

General Features................................................................................. 3

Lithology.............................................................................................. 5

Consolidated Rock........................................................................ 6

Regolith........................................................................................... 6

Structure............................................................................................... 8

Page

Hydrogeologic Terranes............................................................................ C8

Hydrogeologic Terrane Classification.............................................. 11

Hydrogeologic Terrane Maps ........................................................... 13

Hydrogeologic Terrane Subdivisions............................................... 13

Selection and Analysis of Well Records and Variables......................... 16

Selection of Records and Variables................................................... 16

Analysis of Records and Variables................................................... 19

Analysis of Hydrogeologic Terrane Subdivisions.......................... 22

Potential Yield of Water to Wells.............................................................. 22

Summary..................................................................................................... 23

Selected References.................................................................................... 25

Page

ILLUSTRATIONS

[Plates in pocket] 

 

Plate 1. Chart with columns showing the stratigraphic position and lithology of the geologic units in the Valley and Ridge 

	Physiographic Province

2-5. Maps showing the location of hydrogeologic terranes in the Valley and Ridge Physiographic Province in:

2. Eastern and Southeastern United States

3. Maryland, New Jersey, and Pennsylvania

4. Virginia and West Virginia

5. Alabama, Georgia, and Tennessee

Figure 1. Map showing the Appalachian Valley and Piedmont Regional Aquifer-System Analysis study area, physiographic

provinces, and report study area............................................................................................................................................................... 2

2. Boxplots showing variation of specific-capacity values for wells grouped by a selected dozen geologic units ................................... 4

3-4. Maps showing the location of:

3. The areas described by the stratigraphic columns in plate 1......................................................................................................................... 7

4. Major structural features in the Valley and Ridge Physiographic Province in the Eastern and Southeastern United States .............. 9

5. Diagrammatic geologic sections of the Paleozoic rock of the Valley and Ridge Physiographic Province in the

Eastern and Southeastern United States................................................................................................................................................... 10

6. Boxplot showing variation of specific-capacity values for wells grouped by selected lithologic descriptors in the 

Ground- Water Site Inventory data base of the U.S. Geological Survey and the relation of lithologic descriptor 

groups to hydrogeologic terranes.............................................................................................................................................................. 12

7. Diagrammatic hydrogeologic section of the western toe of the Blue Ridge Mountains, southeastern Rockingham

County, Virginia....................................................................................................................^ 14

8-9. Maps showing the:

8. Location of conditions that define the western toe subdivision of the dolomite hydrogeologic terrane in

the Valley and Ridge Physiographic Province in the Eastern and Southeastern United States ....................................................... 15

9. Areal distribution of well records used in the analysis of well records ....................................................................................................... 17

10-14. Boxplots showing:

10. Variation of selected hydrologic and well-construction data for wells used in analysis .......................................................................... 18

11. Variation of specific-capacity values for wells in the dolomite hydrogeologic terrane grouped by categories of well-casing

diameter, primary use of the water, and topographic setting of the well............................................................................................ 20
vi CONTENTS

Figure 12. Variation of specific-capacity values for wells grouped by five hydrogeologic terranes and

two homogeneous data sets................................................................................................................................................................... 21

13. Variation of specific-capacity values for public and industrial supply wells in and out of the western

toe subdivision of the dolomite hydrogeologic terrane in Virginia and West Virginia................................................................. 23

14. Variation of estimated potential yield of water to most-productive wells in hydrogeologic terranes in the

Valley and Ridge Physiographic Province in the Eastern and Southeastern United States......................................................... 24

CONVERSION FACTORS AND VERTICAL DATUM

Multiply

inch (in.)

foot (ft)

gallon per minute (gal/min)

gallon per minute per foot [(gal / min) / ft]

By

25.4

0.3048

0.06309

0.2070

To obtain

millimeter

meter

liter per second

liter per second per meter

Sea level: In this report, "sea level" refers to the National Geodetic Vertical Datum of 

1929 a geodetic datum derived from a general adjustment of the first-order level nets 

of the United States and Canada, formerly called Sea Level Datum of 1929.
REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER TO

WELLS IN THE VALLEY AND RIDGE PHYSIOGRAPHIC PROVINCE IN

THE EASTERN AND SOUTHEASTERN UNITED STATES

BY E.F. HOLLYDAY AND G.E. HlLEMAN

ABSTRACT

The Valley and Ridge Physiographic Province is underlain by 

deformed sedimentary rock of Paleozoic age including dolomite, limestone, shale, and sandstone. Regolith (soil, sediment, and weathered 

rock) covers the Paleozoic rock throughout most of the province. Local 

differences in lithology, structure, and weathering can result in four 

orders of magnitude variation in the water-yielding properties of the 

geologic units that underlie the area. Selected rock types, however, can 

account for a substantial part of this variation because of the unique 

way in which these dense, consolidated sedimentary rock types 

deform and weather to produce secondary openings.

On the basis of relations among rock type, water-yielding openings, and water-yielding properties (as indicated by specific capacity), 

the regolith and consolidated rock were classified and mapped as five 

hydrogeologic terranes alluvium, dolomite, limestone, argillaceous 

carbonate rock, and siliciclastic rock. The hydrogeologic terranes are 

named after the predominant outcrop lithology within them. The western toe of the Blue Ridge Mountains is classified as a subdivision of the 

dolomite hydrogeologic terrane that may produce yields of water in 

excess of 1,000 gallons per minute (gal/min) to public and industrial 

supply wells.

Specific-capacity data for homogeneous data sets, which consist of 

all wells that have the same characteristics in regard to casing diameter, 

primary use of the water, and topographic setting, revealed significant 

differences in water-yielding properties among the five hydrogeologic 

terranes. According to results of Tukey statistical tests at a probability 

(alpha level) of 0.05, 8 out of 10 pairs of hydrogeologic terranes (for 

example, alluvium/limestone) had significantly different median 

specific-capacity values. The median value for public and industrial 

supply wells in the western toe is three times greater than the value for 

comparable wells in the dolomite hydrogeologic terrane elsewhere.

Estimates of potential yields to public and industrial supply wells 

were calculated from specific-capacity data for most-productive wells, 

which have casing diameter of 7 in. or more, discharge water primarily 

for public or industrial supply, and are in a valley. Median constant 

drawdowns, calculated from reported drawdowns, were assumed to 

be between 10 and 90 ft for wells completed in each of the five hydrogeologic terranes, and well-entrance losses were assumed to be negligible. Estimated interquartile ranges in potential yields to 412 mostproductive wells in the five hydrogeologic terranes were 170 to 

580 gal/min, alluvium; 210 to 1,400 gal/min, dolomite; 80 to 

720 gal/min, limestone; 65 to 850 gal/min, argillaceous carbonate rock; 

and 70 to 280 gal/min, siliciclastic rock.

INTRODUCTION

The U.S. Geological Survey (USGS) started the 

Regional Aquifer-System Analysis (RASA) Program in 

1978 in response to congressional concern about the adequacy of water supplies during drought. The purposes of 

the RASA Program were to define the regional hydrology and geology of the Nation's important aquifer systems and to establish a framework of background 

information on geology, hydrology, and water chemistry 

for each aquifer system. This critical information is 

needed to develop an understanding of regional groundwater flow systems and to support efficient groundwater resources management (Sun, 1986, p. 1-8).

In 1988 as part of the RASA Program, the USGS 

began a 6-year study of the ground-water resources in 

parts of 11 States in the Eastern and Southeastern 

United States (Swain and others, 1991). The study was 

called the Appalachian Valley and Piedmont Regional 

Aquifer-System Analysis (APRASA). The APRASA 

team investigated ground-water resources primarily in 

the unglaciated part of the Valley and Ridge, Blue 

Ridge, New England, and Piedmont Physiographic 

Provinces (fig. 1). The Valley and Ridge subproject team 

of the APRASA study focused on a regional analysis of 

the hydrogeology of the carbonate and siliciclastic rocks 

in the Valley and Ridge Physiographic Province.

PROBLEM

A major problem in the effective development, management, and protection of the ground-water resources 

of the Valley and Ridge Physiographic Province is insufficient information on the regional hydrogeologic framework. Definition of the framework is made difficult by 

the complexity of the geology, which causes large variation in the water-yielding properties of the rocks. The

Cl
C2 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

80°

EXPLANATION

Physiographic province

Valley and Ridge

Blue Ridge and 

New England

FIGURE 1. The Appalachian Valley and Piedmont Regional Aquifer-System Analysis study area, physiographic provinces, and report study area.

range in yields of water to wells completed in any particular geologic unit can span several orders of magnitude 

and overlap the ranges of well yields in other units. Any 

analysis of this variation requires a large amount of well 

data to describe differences in the hydraulic characteristics within each unit and to test for significant differences 

in hydraulic characteristics among units.

PURPOSE AND SCOPE

The purpose of this report is to provide background 

information on the regional hydrogeologic setting of the 

Valley and Ridge Physiographic Province in Alabama, 

Georgia, Maryland, New Jersey, Pennsylvania, Tennessee, Virginia, and West Virginia; to describe and map 

hydrogeologic terranes within this setting; to test these

hydrogeologic terranes for significant differences in 

water-yielding properties; and to estimate the quantity of 

water potentially available to wells in these hydrogeologic terranes. Hydrogeologic terranes are defined in this 

report as regionally mappable areas characterized by 

similar rock type and water-yielding properties. The 

hydrogeologic terranes represent areas of distinct hydrologic character. They are intended to help water users 

locate and develop adequate water supplies and to help 

hydrologists interpret the regional hydrogeology.

This report is one of four chapters in U.S. Geological 

Survey Professional Paper 1422 that describes various 

aspects of the geology, hydrology/ and geochemistry of 

ground water in the APRASA study area. These chapters 

include the summary (Chapter A) and descriptions of
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C3

surface- and ground-water relations (Chapter B), the 

hydrogeologic framework of the Valley and Ridge Physiographic Province [Chapter C (this report)], and groundwater geochemistry (Chapter D).

PREVIOUS INVESTIGATIONS

Previous investigations provide maps and descriptions of the geologic units, describe the local quantity 

and quality of the ground water within these units, and 

establish the statistical methods for comparing the wateryielding properties of these units. State geologic maps 

show the distribution of geologic units at a scale of 

1:500,000 for Alabama (Osborne and others, 1989), Georgia (Lawton and others, 1976), and Virginia (Calver and 

Hobbs, 1963). State geologic maps show units at a scale 

of 1:250,000 for Maryland (Cleaves and others, 1968), 

New Jersey (Lewis and Kummel, 1912), Pennsylvania 

(Berg and others, 1980), Tennessee (Hardeman, 1966), 

and West Virginia (Cardwell and others, 1968). Descriptions of the geology of some individual topographic 

quadrangles, counties, parts of counties, or several counties in the area have been published. Many reports 

describing the ground-water resources of a county, parts 

of counties, multicounty areas, or river basin are listed in 

the Selected References section of this report.

The statistical methods used in this report are largely 

based on those used by Knopman (1990, p. 7-9) in her 

analysis of well records in the USGS Ground-Water Site 

Inventory (GWSI) data base. This analysis ranked factors 

that influence the water-yielding potential of the rocks in 

the Piedmont and Valley and Ridge Physiographic Provinces in Pennsylvania. In her analysis, she used values of 

the dependent variable that were transformed by their 

natural logarithm in order to work with a more symmetric distribution than for untransformed data. Nonparametric statistical methods were used because of the 

persistence of outliers and the occasional violation of the 

normality assumption when working with small subsets 

of the data. Statistical analysis included monotonic correlation, one-way and factorial analysis of variance, and 

multiple linear regression. Readers are referred to Knopman (1990) for the details regarding her statistical 

methods.

ACKNOWLEDGMENTS

The authors wish to express their gratitude to Jason E. 

Duke and Paul A. Pearson, Student Trainees (Hydrology), who personally collected 570 records primarily of 

municipal and industrial wells in Alabama, Georgia, Tennessee, Virginia, and West Virginia. They exercised considerable independent judgment while adding these

records to the USGS GWSI data base in each State, compiling a data base for the project, and performing statistical tests and summaries on the data. Without their 

unusual dedication to data collection, data verification, 

and statistical analysis of the data, this report would 

have been far less quantitative than in its present form.

HYDROGEOLOGIC SETTING

The complexity of the geology in the Valley and 

Ridge Physiographic Province results in a large variation 

in the water-yielding properties of the carbonate and 

siliciclastic rocks that underlie the study area. This variation has been observed on the scale of a single county 

(Clark and others, 1976, figs. 17-23; Swain and others, 

1991, p. 30). Within a single geologic unit (formation, 

group, or member) or combination of units, the effects of 

local differences in lithology, structure, and weathering 

can result in a range in water-yielding properties that 

spans several orders of magnitude. If specific capacity 

(the discharge of a well divided by the resulting drawdown) is considered to be a measure of the wateryielding properties, then the range in water-yielding 

properties of a single unit can span four orders of magnitude and overlap the ranges of many other units (fig. 2).

GENERAL FEATURES

The Valley and Ridge Physiographic Province is 

underlain by deformed sedimentary rock of Paleozoic 

age that overlies metamorphic and igneous rock of Precambrian age. The metamorphic and igneous rock is not 

discussed in the report because it has low permeability 

relative to the sedimentary rock and occurs either at 

depths greater than 1,000 ft or in limited outcrop within 

the study area. The Paleozoic sedimentary rock is, in 

order of abundance, carbonate rock (dolomite and limestone), shale, and sandstone (Colton, 1970, p. 10). Folding 

and faulting of this rock, which was initially deposited in 

an almost horizontal position, has resulted in large structural features (anticlines, synclines, and thrust faults) 

that include several tens of square miles. Regolith (soil, 

sediment, and weathered rock) covers the consolidated 

rock throughout most of the study area.

Ground water in the consolidated rock of the study 

area resides in and flows through secondary openings 

(joints, fractures, bedding-plane partings, and dissolution openings). The secondary openings were formed by 

mechanical breakage and enlarged by chemical weathering of the consolidated rock. These openings, which were 

produced after the rock was lithified, contrast with the 

primary openings that existed between grains in the 

original sediment.
2?

c5rt

B

to

J,,

§8-'

o'

1*o

ft __

O 1

o ^ ' 

A

DO

DO O Q

O2 O m

op * o TC L^ . n 1

^ 5 "j ci O c

Q< -D ? Q C

mm m HO

/- 

O

c 

z

Q

, __ . m

 Q (/)

 H DO ^

O ^

OQ

1 J? ^ ^-^ 

" ^rocn-^icoco CD w dC~ 

<< ^§§ § 22S ^ 8 ^ >

1

3

1

00

!

p

ft*

o

ft

D8

3

qgft

2,

o 

'2- o'

1

F

§3 q_j

^ a w 3

o BT °

° 1 W

Sfo. hS OO ^^* M

» P. > 

is ^

|| 8

sj ^

^0 DO O

^3" 03

c« ^ > ? ii

PS n-s

1 iS l

3 ^ >

a H H

g en m

g.

t/3

O

o

m

CHEMUNG FORMATION

BRALLIER FORMATION

TRIMMERS ROCK

FORMATION

MAHANTANGO FORMATION

ONONDAGA GROUP

RAMSEYBURG MEMBER,

JWVRTINSBURG FORMATION

ONTELAUNEE FORMATION

EPLER FORMATION

NITTANY DOLOMITE

RICHLAND FORMATION

ZULLINGER FORMATION

ELBROOK LIMESTONE

SPECIFIC CAPACITY, IN GALLONS PER MINUTE PER F

OF DRAWDOWN

' ' ' " 1M|

01 

9 1 

C)

 O 1 

- 0 1 

9 1 

0 I 

0 | 

-0| 

- 0 | 

0 1 

i O 1

1 1 1 1 1 1 1 1

 1

 1 C

1 ' ' " 1MI ' ' ' " 1MI 

0

)

 10

 1 0

 1 o

 1 o

 

1 n' ^

__

 

 1 0

 1 0

1 , , , . ,,.,1 , , , , .,.,1 
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C5

Ground-water flow systems in consolidated rock tend 

to be restricted in depth and areal extent because of the 

restricted vertical extent of major weathering and the 

change in geologic structure over short distances. Weathering decreases with depth, thereby restricting the depth 

of development of the more permeable zones. Faults 

commonly restrict the areal extent of flow systems by 

cutting across geologic units and juxtaposing permeable 

rock and less permeable rock. Folds restrict the areal 

extent of flow systems by distorting the horizontal layering and exposing both permeable and less permeable 

rock units at the land surface. In addition, the widespread occurrence of trellis drainage networks in the Valley and Ridge Physiographic Province supplement 

restrictions on the areal extent of ground-water flow systems imposed by faults and folds. For these reasons, flow 

systems in the more permeable rock typically occupy a 

space of a few hundreds of feet in depth by tens or hundreds of square miles in area. For example, a map of the 

potentiometric surface indicates that ground-water flow 

in the Spring Creek basin of south-central Pennsylvania 

is restricted to an area of approximately 10 mi by 17.5 mi 

(Wood, 1980, p. 10-12 and fig. 5). A similar map indicates 

that flow in the Carson Spring basin of the northwestern 

Valley and Ridge, Tennessee, is restricted to an area of 

approximately 2.3 mi by 4 mi (Webster and Carmichael, 

1993, p. 5-10 and fig. 15). This is in contrast to areas of 

extensive unconsolidated deposits such as the Atlantic 

and Gulf Coastal Plain where flow systems can occupy a 

space of many hundreds of feet in depth by thousands or 

tens of thousands of square miles in area.

The largest ground-water flow systems in the Valley 

and Ridge Physiographic Province discharge at large 

springs (450-45,000 gal/min) that are fed by conduits in 

carbonate rock. These conduits discharge at points rather 

than along extended lines of seeps. In the study area in 

Pennsylvania, 90 percent of springs that discharge 

100 gal/min or more produce water from carbonate rock 

(Saad and Hippe, 1990, p. 8). A substantial number of 

wells that discharge more than 1,000 gal/min in the 

study area are located adjacent to large springs that drain 

carbonate rock.

The quality and quantity of ground water in the consolidated rock are influenced by the depth of occurrence 

of the water and the lithology of the rock through which 

it flows. Freshwater occurs in usable quantities almost 

everywhere in consolidated rock to depths of several 

hundred feet, but tends to be deeper in carbonate rock 

than in argillaceous siliciclastic rock. Freshwater, which 

is in quantities too small for economic use, and brine 

occur in this rock to depths of a few thousand feet. One 

exception is the deep, warm freshwater in the Oriskany 

Sandstone and stratigraphically equivalent or adjacent 

rock units in Virginia and West Virginia. This ground

water probably circulates as deep as 1,800 ft below land 

surface where it is warmed by the surrounding rock 

before returning to land surface to discharge at hot 

springs (Hobba and others, 1979). Compared with siliciclastic rock, carbonate rock tends to have more variable 

water-yielding properties, larger maximum potential 

yields of water to wells, and water with less dissolved 

iron, but greater hardness.

LITHOLOGY

Differences in the lithology of selected rock types can 

account for a substantial part of the variation in the 

water-yielding properties of the rock. Different 

unconsolidated materials have different primary porosity and permeability as a result of differences in their 

grain size, packing, and cementation. Different consolidated sedimentary rocks have different secondary porosity and permeability as a result of differences in the way 

they deform and weather. Dolomite or limestone that is 

mostly free of clay or shale interbeds tends to deform 

plastically or develop few fractures at great depth within 

the Earth's crust. At shallow depth during weathering, 

the dissolution of soluble minerals along joints, fractures, 

and bedding-plane partings causes widening of these 

planar openings and results in a honeycomb rock that 

has variable, but commonly high, permeability. The pure 

or nearly pure carbonate rock typically is covered by 

only a few feet of residuum. Argillaceous carbonate rock 

also tends to deform plastically and develop fewer fractures. During weathering, clays are likely to swell or otherwise fill the few fractures and dissolution openings, 

which results in a rock that has low permeability. This 

rock usually is covered by a few tens of feet of residuum. 

Argillaceous siliciclastic rock generally deforms and 

weathers in a manner similar to argillaceous carbonate 

rock but lacks any substantial development of dissolution openings and has low permeability. Sandstone that 

is mostly free of clay or shale interbeds develops fractures at depth, but during weathering, these fractures are 

not widened by dissolution. The permeability of clean 

sandstone is higher than that of argillaceous siliciclastic 

rock but lower than that of clay-free carbonate rock. Nonargillaceous sandstone typically is covered by a few feet 

of stony residuum. Thus, because these selected, sedimentary rock types deform and weather differently, each 

type tends to have unique water-yielding characteristics.

Differences in the thickness and texture of regolith 

(unconsolidated materials) can account for a substantial 

part of the variation in the water-yielding properties of 

geologic materials in an area. Thick, coarse-grained 

regolith has a high permeability and, where saturated, 

can form a productive aquifer above the consolidated
C6 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

rock. Although thick fine-grained regolith has a low permeability, where saturated, it can provide abundant 

recharge to the underlying aquifers in consolidated rock. 

The water-yielding properties of geologic materials in 

areas with thin regolith, which stores little water, are predominantly influenced by the properties of the underlying consolidated rock.

CONSOLIDATED ROCK

The consolidated sedimentary rock units in the study 

area represent a wide variety of rock types dolomite; 

magnesian limestone; limestone; argillaceous carbonate 

rock; shale, mudstone, and siltstone; sandstone; conglomerate; interbedded sandstone, siltstone, and shale 

(Patchen and others, 1985a, 1985b). The authors determined that most of these rock types could be grouped 

into a classification wherein each class is hydrologically 

unique. Under this classification, the rock types of hydrologic significance in the study area are these sedimentary 

rocks: dolomite, limestone, argillaceous carbonate rock, 

and siliciclastic rock. The distribution through time of 

these rock types and local geologic units comprising 

them and their location across the study area (fig. 3) are 

illustrated by 21 stratigraphic columns in plate 1. For the 

most part, the geologic unit names in plate 1 conform to 

the usage of the State Geological Surveys. The columns 

contain the map symbols used in the State geologic maps 

referenced at the top of the columns in plate 1. The symbols may be used to relate the map units to a particular 

geologic unit, rock type, and hydrologic significance.

For the hydrologic purpose of this report, the dolomite rock type includes: (1) units that are predominantly 

dolomite (such as the Shady Dolomite in the Lower Cambrian Series), (2) a combination of dolomite and sandstone or chert (Gatesburg Formation and Copper Ridge 

Dolomite in the Upper Cambrian Series), and (3) dolomite and limestone with as much as 70 percent limestone 

(Elbrook Limestone in the Middle and Upper Cambrian 

Series in Virginia). The limestone rock type includes units 

that are predominantly limestone (Lincolnshire Limestone, Middle Ordovician Series in Virginia and West Virginia) and limestone with less than 30 percent dolomite 

(Stonehenge Limestone, Lower Ordovician Series).

The argillaceous carbonate rock type includes units 

that are predominantly clay-rich dolomite or limestone 

(Chambersburg Limestone in the Middle Ordovician 

Series in Maryland and Pennsylvania) as well as shale 

units that contain abundant calcite or magnesium calcite 

(Wills Creek Formation, Upper Silurian Series). The 

argillaceous carbonate rock type also includes undifferentiated geologic units that may be a combination of 

limestone, argillaceous carbonate rock, and siliciclastic 

rock (Middle and Upper Ordovician Series rock, undifferentiated, in Virginia). The siliciclastic rock type 

includes units that are predominantly shale with little or 

no carbonate content (such as the Chattanooga Shale, 

Lower Mississippian and Upper Devonian Series), siltstone (Maccrady Shale, Lower and Upper Mississippian 

Series), sandstone (Clinch Sandstone, Lower Silurian 

Series), and conglomerate (Shawangunk Conglomerate, 

Lower and Middle Silurian Series in New Jersey) that 

consist of clay minerals, quartz grains, or siliceous rock 

fragments. In New Jersey and eastern Pennsylvania, the 

siliciclastic rock type also includes a unit that contains a 

substantial amount of slate (Martinsburg Shale, Middle 

and Upper Ordovician Series).

Different rock types characterize different rock ages 

(pi. 1). Substantial amounts of dolomite are only in the 

carbonate rock that is mostly of Lower Cambrian 

through Middle Ordovician Series. Limestone is common in the Cambrian and Ordovician Systems throughout the study area, the Upper Silurian and Lower 

Devonian Series in the northern half of the study area, 

and the Mississippian System in the southern half of the 

study area. Siliciclastic rock is particularly abundant in 

rock series younger than the Middle Ordovician. The 

argillaceous carbonate rock typically is in a stratigraphic 

interval between siliciclastic rock and either dolomite or 

limestone.

Different rock types of the same age characterize different parts of the study area (pi. 1). For example, the 

siliciclastic and argillaceous carbonate rocks in the Upper 

Silurian and Lower Devonian Series in New Jersey (column 1) grade laterally into limestone and argillaceous 

carbonate rocks in Pennsylvania (columns 3 and 4) and 

into limestone and siliciclastic rocks in Maryland, Virginia, and West Virginia (columns 5-11). Within these 

same two series, most geologic units are missing and the 

thickness of the section approaches zero in the southwestern half of the study area (columns 12-21). Different 

rock types of the same age may even characterize different parts of the same column area (column 9, Middle 

Ordovician Series) where a thrust fault has juxtaposed 

rock types that originally were in compositionally different and widely separated parts of the same depositional 

basin.

REGOLITH

Regolith varies in thickness from 0 to 450 ft and in 

texture from clay to gravel. It was either formed in place 

by the weathering of the underlying bedrock (residuum) 

or deposited after being transported from the place of 

weathering (till, colluvium, and alluvium). Only a small 

part of the regolith is shown on maps in this report 

because of the thinness and variable texture of most of 

these materials.
EXPLANATION

Column 

number

1

2

3

4

56

7

8

9

101112

Column name

Northwestern New Jersey Eastern Pennsylvania 

Southeastern Pennsylvania South-central Pennsylvania 

Washington County, Maryland Allegany County, Maryland Northeastern West Virginia 

Northwestern Virginia 

Montgomery, Roanoke, Botetourt, and Rockbridge Counties, Virginia Craig, Alleghany, Bath, and Highland

Counties, Virginia Southeastern West Virginia Washington, Smyth, Wythe, and Pulaski Counties, Virginia 

Scott, Russell, Tazewell, Bland, and

Giles Counties, Virginia Lee and Wise Counties, Virginia Northeastern Valley and Ridge,Tennessee

Column number

1617

1819

2021

Column name

Northwestern Valley and Ridge,

Tennessee 

Southeastern Valley and Ridge,

Tennessee

Valley and Ridge and Plateau, Georgia Valley and Ridge, Northern Segment, Alabama 

Calhoun, St. Clair, and Talladega

Counties, Alabama 

Valley and Ridge, Southern Segment, Alabama

Boundary of area of stratigraphic column Number represents column in plate 1Boundary of study area of report

Column boundaries modified 

from Patchen, Avary, and 

Erwin (1985a and 1985b)

100 MILES

100 KILOMETERS

ffi o

o o

H 

O

s

oI-H

Qf 

H

O <I-H *

Q

Base from U.S. Geological Survey 

1:2,500,000 scale map

FIGURE 3. Location of the areas described by the stratigraphic columns in plate 1.
C8 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

Much of the consolidated rock in the study area is 

covered by residuum or glacial till. A fine-grained residuum covers the valleys and upland flats that comprise 

much of the study area. Residuum is thin (commonly less 

than 5 ft) on shale and most carbonate rock. Residuum 

can be thick (more than 50 ft) on rock that contains substantial amounts of blocky sandstone or chert because 

these resistant materials protect the surface of the residuum from erosion (Hack, 1965, p. 45^9, fig. 35). A protective surface forms either in place as a lag concentrate 

or as the result of the accumulation of colluvial or alluvial material transported from adjacent, topographically 

higher resistant rock. Glacial till with a sandy or clayey 

matrix covers much of the uplands in New Jersey and 

northern and eastern Pennsylvania and is commonly less 

than 3 ft thick (Sevon, 1989).

Alluvium underlies most river flood plains and is in 

terraces at the sides of valleys with streams that drain 

areas of resistant, siliciclastic rock. In major valleys of 

New Jersey and parts of northern and eastern Pennsylvania, alluvium commonly exceeds 30 ft in thickness and is 

coarse grained, well sorted, and derived directly or indirectly from glacial deposits. Alluvium in this part of the 

study area produces some of the largest yields of water to 

wells of any geologic units in the study area and is 

mapped as part of the report (pis. 2 and 3).

Thin, stony colluvium overlies residuum or bedrock 

on hill and mountain slopes that are crested by resistant 

siliciclastic rock (Hack, 1965, p. 30-32; Mills and Delcourt, 1991, p. 614-615). This stony colluvium commonly 

grades down the slope into dissected alluvial terraces 

that contain cobble gravel, sand, and sandy loam. Adjacent to the Blue Ridge Physiographic Province along the 

southeastern edge of the study area, colluvium and alluvium interfinger to form a regolith apron that covers 

thick residuum and carbonate bedrock. The area of this 

apron has been associated with large springs (Becher and 

Root, 1981, p. 12) and wells producing in excess of 

1,000 gal/min (Leonard, 1962, p. 208, 209).

STRUCTURE

Differences in geologic structure can account for some 

of the variation in the water-yielding properties of the 

rock in the study area. Large-scale structures (anticlines, 

synclines, and thrust faults) juxtapose rock types that 

have different water-yielding properties and bring rock 

to the land surface where secondary porosity and permeability can be enhanced by chemical weathering. Smallscale structures (fractures, joints, and bedding-plane 

partings) provide openings that allow water to enter and 

move through an otherwise dense rock mass.

Large-scale structures (fig. 4) control the distribution 

and extent of the geologic units. Complex anticlines, such

as the Nittany Arch and Wills Mountain Anticline in the 

northeastern half of the study area and Powell Valley, 

Wills Valley, and Murphree Valley Anticlines in the 

southwestern half, bring the older rock to land surface. 

Complex synclines, such as the Lackawanna, Broad Top, 

Massanutten, and Catawba Synclines and the Anthracite 

Basins in the northeastern half of the study area and the 

Bays Mountain, Floyd, Coosa, and Cahaba Synclines in 

the southwestern half, preserve the younger rock in their 

centers. In the northeastern half of the study area, the 

Great Valley and the Shenandoah Valley are underlain by 

intricately folded and faulted rock along the southeastern edge of the Valley and Ridge Physiographic Province. The southeastern edge of most of the province 

generally has closely spaced faults, overturned and 

recumbent folds, and outcrops of the oldest rock.

Thrust faults, which range in attitude from nearly 

horizontal to steeply dipping (fig. 5), cut across and displace the Paleozoic rock units. Faults place older rock 

from the southeast over younger rock to the northwest. 

In the northeastern half of the study area, the displacement along thrust faults decreases with decreasing 

depth, and anticlinal folds replace the faults at land surface (fig. 5, A-A' and B-B'). Large anticlinal folds commonly are at land surface where the thrust faults ramp 

upward from depth [fig. 5, B-B', (Wills Mountain Anticline), E-E' (anticline in the footwall of the Rome Fault)]. 

Near the middle of the study area (fig. 5, C-C' and D-D'), 

many thrust faults, such as the Pulaski and Saltville 

Faults, bring Ordovician and Cambrian rocks to the land 

surface, repeating the stratigraphic section not only vertically but also from northwest to southeast.

The rock has been broken by small-scale structures 

throughout the Valley and Ridge. The frequency of intersection, density, and geometry of the fractures, joints, 

and bedding-plane partings vary with the lithology, bed 

thickness, and structural setting. Locally, all or some of 

these minor planar openings can be sealed by deposition 

of natural cementing materials subsequent to deformation or can be filled with fine-grained sediment transported by infiltrating surface water.

HYDROGEOLOGIC TERRANES

Hydrogeologic terranes are regionally mappable 

areas characterized by similar rock type and wateryielding properties. A classification of hydrogeologic terranes was developed and maps of hydrogeologic terranes were compiled so that the study area could be 

subdivided on the basis of the unique water-yielding 

properties of each hydrogeologic terrane.
EXPLANATION

Major structural feature

AB Anthracite Basins

AF Allegheny Front

BM Bays Mountain Syncline

BTS Broad Top Syncline

C Catawba SynclineCA Cahaba Syncline

CF Cartersville Fault

CO Coosa SynclineF Floyd SynclineGSF Great Smoky Fault

GV Great ValleyLS Lackawanna SynclineM Massanutten SynclineMV Murphree Valley Anticline NA Nittany ArchNMF North Mountain FaultPF PulaskJ Fault

PV Powell Valley Anticline

RF Rome Fault

SF Saltville Fault

SV Shenandoah Valley

WM Wills Mountain Anticline

WV Wills Valley Anticline

Physiographic Province

AP Appalachian PlateausBR Blue Ridge

NE New England

P Piedmont

VR Valley and Ridge

J Approximate location of major 

structural feature

-A' Approximate trace of diagrammatic 

section shown in figure 5

Boundary of report study areaBoundary of physiographic province

75°

Thrust fault Sawtooth on upper 

plate of thrust fault. Locally is a 

report area boundary

35'

/ 50 100 MILES

50 100 KILOMETERS

oQ 

M 

O r^ O Q

Base from U.S. Geological Survey 

1:2,500,000 scale map

Structural features modified from Cardwell, Erwin,

and Woodward (1968); King and Beikman (1974);

Osborne and others (1989); and Rodgers (1953)

Md 

Q 

W 1J

§

M

FIGURE 4. Location of major structural features in the Valley and Ridge Physiographic Province in the Eastern and Southeastern United States.
CIO REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

Nittany 

Arch

Anthracite 

Basins

Great 

Valley

South-central Pennsylvania 

APPROXIMATELY 80 MILES

Geology from Berg 

and others (1980)

£8

Wills 

Mountain 

Anticline

North

Mountain

Fault

Massanutten 

Syncline

Northeastern West Virginia and Northwestern Virginia 

 APPROXIMATELY 70 MILES 

Geology modified from 

Woodward (1985, section 11)

St. Clair 

Fault

Saltville Pulaski 

Fault Fault

Geology modified from 

Woodward (1985, section 16)

Giles and Pulaski Counties, Virginia i 

 APPROXIMATELY 50 MILES '

Chattanooga Hunter Saltville

D Fault Valley Fault

I Fault I

Dumplin Great Tuckaleechee 

Valley Smoky Cove DFault Fault I

Geology modified from 

Woodward (1985, section 23)

Anderson, Knox, and Blount Counties, Tennessee I 

 APPROXIMATELY 50 MILES '

Wills Lookout Rome 

E Valley Syncline Fault 

Anticline I

Coosa 

Fault

Cartersville 

Fault E.

Geology modified from 

Woodward (1985, section 29)

DeKalb and Cherokee Counties, Alabama i 

 APPROXIMATELY 50 MILES '

| Pennsylvanian rock

|_| Mississippian rock

Devonian rock

EXPLANATION

| Silurian rock 

| | Ordovician rock 

[ J Cambrian rock

Rock of Piedmont and Blue Ridge 

Physiographic Provinces and basement

Approximate location of fault 

Approximate location of geologic contact

FIGURE 5. Diagrammatic geologic sections of the Paleozoic rock of the Valley and Ridge Physiographic Province in the Eastern and Southeastern United States. See figure 4 for location of sections.
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE Cll

HYDROGEOLOGIC TERRANE CLASSIFICATION

Hydrogeologic terrane classes were defined based on 

the relation of rock type to the nature of water-yielding 

openings in the rock and the water-yielding properties of 

the rock. Twelve lithologic descriptors from the GWSI 

data base were used to identify the rock type for classifying hydrogeologic terranes. For wells with lithologic 

descriptors, specific-capacity values were used as an 

approximate measure of water-yielding properties. The 

following five hydrogeologic terrane classes, one consisting of regolith and four consisting of consolidated sedimentary rock, are defined below: alluvium, dolomite, 

limestone, argillaceous carbonate rock, and siliciclastic 

rock. The relations among the 5 hydrogeologic terranes, 

the 12 lithologic descriptor groups, and the specific 

capacity of wells are shown in figure 6. Specific-capacity 

data were sufficient to treat each of the lithologic descriptor groups as a separate hydrogeologic terrane; however, 

as shown in figure 6, it is unlikely that all lithologic 

descriptor groups would have unique water-yielding 

properties according to specific capacity. The authors 

elected to reduce the number of hydrogeologic terranes 

in order to increase the likelihood of identifying hydrogeologic terranes that would be unique in their wateryielding properties.

Hydrologic intuition may conflict with apparent differences in the median specific-capacity values of wells 

completed in selected pairs of lithologic descriptor 

groups (fig. 6). For example, if it is assumed that all materials are well sorted, then sand and gravel (SDGL) would 

be expected to have a greater median value than sand 

(SAND) because the larger grain sizes in sand and 

gravel (SDGL) are commonly related to greater permeability (Wenzel, 1942, p. 11-13; Freeze and Cherry, 1979, 

p. 350-352). Limestone (LMSN) would be expected to 

have a greater median value than dolomite (DLMT) or 

limestone and dolomite (LMDM), because limestone 

(LMSN) dissolves more quickly than dolomite (White, 

1988, p. 146). A large part of the reason for the apparent 

differences between selected pairs is that wells in each 

lithologic descriptor group have different diameter, 

intended water use, and topographic setting. As discussed later in the report in the section "Analysis of 

Records and Variables," differences in well characteristics have a significant effect upon median specificcapacity values.

The distinction between regolith and consolidated 

rock was made on the basis of differences in the nature of 

the water-yielding openings and water-yielding properties. Well-sorted, coarse-grained alluvium of glacial origin is the only regolith that covers a substantial area and 

yields large quantities of water to wells from pore spaces 

between sediment grains. Water in the consolidated rock

occupies fractures, bedding-plane partings, or dissolution openings. In addition, median specific-capacity 

values of wells completed in the alluvium hydrogeologic terrane sand (SAND), and sand and gravel 

(SDGL) were greater than those for wells completed in 

consolidated rock hydrogeologic terranes (fig. 6). In 

addition to differences due to well characteristics, sand 

(SAND) may have an apparently greater median 

pecific-capacity value than sand and gravel (SDGL) 

because the sand may be better sorted and may have 

less clay than the sand and gravel.

Dolomite and limestone were defined as distinct 

hydrogeologic terrane classes on the basis of their composition, the nature of water-yielding openings, and 

water-yielding properties. Large dissolution openings 

are unique features of these carbonate rocks and occur 

in addition to the joints, fractures, and bedding-plane 

partings characteristic of siliciclastic rock; and contrast 

with the intergranular openings of unconsolidated 

material. Specific-capacity values further differentiate 

dolomite and limestone from other rock types. Wells 

completed in the dolomite hydrogeologic terrane dolomite (DLMT), and limestone and dolomite (LMDM) had 

the greatest median specific-capacity values of wells 

completed in consolidated rock hydrogeologic terranes 

in the study area (fig. 6). Wells completed in the limestone hydrogeologic terrane limestone (LMSN) had 

the second greatest median specific-capacity value.

In addition to differences because of well characteristics, limestone (LMSN) may have an apparently much less 

median specific-capacity value than dolomite (DLMT) or 

limestone and dolomite (LMDM) because many wells 

assigned by the field investigator to limestone may actually penetrate argillaceous limestone. Part of the difference between limestone and dolomite also may be that 

many dolomite units in the study area contain either 

chert or thin beds of sandstone, which weather to produce thick regolith. In some places, the thick regolith is 

saturated and recharges the underlying dolomite aquifer.

Argillaceous carbonate rock also was defined as a 

hydrogeologic terrane class on the basis of composition 

and nature of water-yielding openings and properties. 

Like dolomite and limestone, argillaceous carbonate rock 

mostly consists of magnesium calcite or calcite and can 

develop dissolution-enlarged secondary openings. However, the clay-mineral component of this rock mostly is 

insoluble, and when the rock is dissolved, the clay residue 

tends to clog some of the secondary openings and to 

reduce the water-yielding capacity of the rock. Median 

specific-capacity values for wells completed in the argillaceous carbonate rock hydrogeologic terrane limestone 

and shale (LMSH), and dolomite and shale 

(DMSH) were less than median values for wells completed in the dolomite or limestone hydrogeologic 

terranes (fig. 6).
C12 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

NUMBER OF WELLS

1,000 F

<

o 

2

DC 

LU 

0.

LU

DC 

LU

100

10

§1

<DC 

(DO

0.1

O

o 

o

o

LU 

0.

co

0.01

LITHOLOGIC

DESCRIPTOR

GROUP

HYDROGEOLOGIC 

TERRANE

: 1 1 1

O

0 o

; 5[M!-

: 0

- *

- 0

o

o

- I

o -1-

o o

II 1 1

Q -=1 1- ^ Z I

Z CD ^ Q CO CO

< O _i -5; ^ ^

\Jl _^/v°. _!A_ v\_±

1

0

I

0

1

I

CO2

Qy

1

O

1

T

0

i

2

_i

CD

\ °

1

0

1

T

O

1

 I

CO

o

CO

1

o

1

T

o

1

LU_l I

CO

1

0

I

T

o

1

CO

o

^y

CO

1 :

-

:

o ~

I;

-

T 1

0

-

-

1

z

CO_l w /

V

2 

>

13

LU

O 

O

LU

R

CO 

LU

cow*: I3I-O 0<0 

LU ZDC oO

< CD

-I DC

d<

CDO

DC

<

po 

wO

<DC 

O

o

^ 

CO

SAND Sand

SDGL Sand and gravel

DLMT Dolomite

LMDM Limestone and dolomite

LMSN Limestone

LMSH Limestone and shale

EXPLANATION 

Lithologic descriptor group

DMSH Dolomite and shale 

CGLM Conglomerate 

SDSL Sandstone and shale 

SHLE Shale 

SNDS Sandstone 

SLSN Siltstone

Percentile Indicates percentage of measurements 

equal to or less than indicated values

95th 

90th 

75th

50th

25th 

10th 

5th

FIGURE 6. Variation of specific-capacity values for wells grouped by selected lithologic descriptors 

in the Ground-Water Site Inventory data base of the U.S. Geological Survey and the relation of lithologic descriptor groups to hydrogeologic terranes.
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C13

Consolidated, non-carbonate, clastic rock was combined into a separate hydrogeologic terrane class on the 

basis of composition and the nature of water-yielding 

openings and properties. This rock, which mostly consists of insoluble silicate mineral grains or rock fragments, is termed "siliciclastic rock/' It does not have 

primary, intergranular, water-yielding openings and generally does not develop secondary dissolution openings. 

The water-yielding openings in the siliciclastic rock are 

almost exclusively joints, fractures, and bedding-plane 

partings. Median specific-capacity values for wells completed in the siliciclastic rock hydrogeologic terrane conglomerate (CGLM), sandstone and shale 

(SDSL), shale (SHLE), sandstone (SNDS), and siltstone 

(SLSN) were similar to each other, but as a group, they 

were less than the values for all lithologic descriptor 

groups in other hydrogeologic terranes except dolomite 

and shale (DMSH) (fig. 6;. In addition to differences due 

to well characteristics, sandstone (SNDS) may have the 

same median specific-capacity value as shale (SHLE) or 

sandstone and shale (SDSL) because the sandstone that 

has records with lithologic descriptor data is predominantly sandstone interbedded with shale or sandstone 

with a significant clay content.

HYDROGEOLOGIC TERRANE MAPS

The hydrogeologic terrane maps (pis. 2-5) were compiled from the hydrogeologic terrane classification, the 

predominant lithology of each geologic unit, and the 

State geologic maps. The predominant lithology (pi. 1) 

was determined primarily from the lithologic descriptions in the explanations on the State geologic maps, supplemented by data tables available for the Correlation of 

Stratigraphic Units of North America charts (Patchen 

and others, 1985a and 1985b), county reports on the geology and ground-water resources, and the lithologic 

descriptors assigned to wells in each unit in the GWSI 

data base. The rock types shown by color in plate 1 correspond exactly to the hydrogeologic terrane classes in 

plates 2-5. Uncolored (white) parts of the maps represent 

areas where the geologic units consist of a mix of rock 

types or where the geologic units consist of rock characteristic of the Blue Ridge, New England, or Piedmont 

Physiographic Provinces.

The hydrogeologic terranes (pis. 2-5) coincide with 

the outcrop pattern of the geologic units with the corresponding predominant lithology and reflect the geologic 

structure of the area. In the northeastern half of the Valley and Ridge Physiographic Province (pi. 2), where few 

thrust faults are exposed and do not bring the older carbonate rock to the surface, the siliciclastic rock hydrogeologic terrane characterizes much of the area. The

dolomite and limestone hydrogeologic terranes mostly 

are adjacent to the southeastern margin of this half of the 

province or are where folds bring them to the surface as 

in the Nittany Arch. In the southwestern half of the province, numerous thrust faults repeat portions of the stratigraphic section and bring rock of all four hydrogeologic 

terranes to land surface in bands oriented parallel to the 

regional strike. In general, the argillaceous carbonate 

rock hydrogeologic terrane occurs between the siliciclastic rock hydrogeologic terrane and other carbonate 

hydrogeologic terranes. The alluvium hydrogeologic terrane generally coincides with the major valleys in the 

northeastern one-fifth of the study area (pis. 2 and 3). The 

siliciclastic rock hydrogeologic terrane includes more 

than half the entire study area; the alluvium hydrogeologic terrane includes the least area.

HYDROGEOLOGIC TERRANE SUBDIVISIONS

The five hydrogeologic terranes can be subdivided on 

the basis of factors in addition to rock type. The five 

hydrogeologic terranes include a wide range of hydrologic, structural, and geomorphic conditions. The terranes are regional, comprehensive, and essentially 

include the entire study area. Areas of more localized 

hydrologic conditions can be defined within these hydrogeologic terranes. An example of the subdivision of the 

dolomite hydrogeologic terrane is the western toe of the 

Blue Ridge Mountains, which is largely defined based on 

geomorphic conditions.

The western toe of the Blue Ridge Mountains (western toe) is an area characterized by an apron of colluvium 

and alluvium at the toe of the western slope of the Blue 

Ridge Mountains (Hinkle and Sterrett, 1976, p. 50 

and 51). The colluvium consists of stony material shed 

from outcrops of resistant, siliciclastic rock principally 

the Antietam Quartzite and equivalent units that is 

associated with the Blue Ridge Mountains. The apron 

overlies fine-grained residuum and dolomite bedrock at 

the southeastern edge of the Valley and Ridge 

Physiographic Province (fig. 7). In parts of the western 

toe, the combined thickness of colluvium, alluvium, and 

residuum exceeds several 100 ft (King, 1950, p. 55 and 

59). Within Augusta, Rockbridge, and Rockingham 

Counties, Virginia (fig. 8), the western toe has public and 

industrial supply wells that individually may produce in 

excess of 1,000 gal/min and together produce more than 

20 million gallons of water per day from dissolution 

openings in the dolomite that underlies the thick regolith 

(Leonard, 1962; Hinkle and Sterrett, 1976, 1978; Meng 

and others, 1985, p. 431).

The geomorphic conditions defining the western toe, 

namely an apron of colluvium and alluvium that was
APPROXIMATELY 

FEET 600 

s f

p

5T

JO

8?<r I'

I

no

: !-! y/ .11

-

- 

3

a

w

X fl

r

>

H

i.3

I

IVNOIOSH waxsA^-na^mbv Nvmovivddv SISAIVNV ASTIVA CINV 
EXPLANATION

Approximate location of conditions that define 

the western toe subdivision of the dolomite hydrogeologic terrane

Boundary of county and study area of report. Named counties are discussed in the text

0 50 100 MILES

____ 

i _____i i i

0 50 100 KILOMETERS

Base from U.S. Geological Survey 1:2,500,000 scale map

FIGURE 8. L
C16 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

derived from resistant, siliciclastic rock and that overlies 

fine-grained residuum and dolomite bedrock at the 

southeastern edge of the Valley and Ridge Physiographic 

Province, extend beyond Virginia. These same conditions 

exist in parts of 36 counties in the study area (fig. 8). As 

examples, Becher and Root (1981, p. 32 and fig. 8) have 

mapped an area of thick colluvium and alluvium that 

overlies the Tomstown Dolomite in southeastern Cumberland County, Pennsylvania. An area of thick colluvium and residuum overlies the Shady Dolomite on the 

slope of Coldwater Mountain in southern Calhoun 

County, Alabama. Scott, Harris, and Cobb (1987, fig. 2 

and pi. 1) included this area in the recharge area of Coldwater Spring. This spring has a measured discharge averaging 22,000 gal/min and is estimated to be the largest 

spring in the Valley and Ridge Physiographic Province.

SELECTION AND ANALYSIS OF WELL 

RECORDS AND VARIABLES

SELECTION OF RECORDS AND VARIABLES

A statistical analysis of well records was performed to 

determine if significant differences in water-yielding 

properties among the hydrogeologic terranes could be 

detected. In order to perform valid tests of significance, 

the authors first analyzed selected well records to investigate the influence of independent variables (casing diameter, primary use of the water, and topographic setting) 

upon the dependent variable (specific capacity).

All wells with values for specific capacity and well 

location were selected for inclusion in the data base for 

the study. Most of these were domestic wells, which generally have low yield and small specific capacity. Domestic wells commonly are not located in the most favorable 

setting, drilled to the optimum depth, developed for sufficient time, and equipped to produce large quantities of 

water. Consequently, domestic wells are not the most 

reliable source of information for classifying hydrogeologic terranes, investigating the influence of independent 

variables on specific capacity, testing for significance, or 

estimating the potential yield of water to wells. However, 

in a trade of quantity of data for quality of data, a large 

sample set (domestic wells together with nondomestic 

wells) was used to classify hydrogeologic terranes and to 

investigate the influence of independent variables, 

because the smaller size of the sample of nondomestic 

wells reduced the ability to detect potentially significant 

terrane classes and variables. A smaller sample set (nondomestic wells only) was used to test for significant differences among hydrogeologic terranes and to estimate 

potential yield of water to wells.

Records for wells with 6,891 reported specificcapacity values were retrieved from the GWSI data base 

for the eight-State area. Most of these records also 

included other data of interest well yield, well depth, 

and well-casing diameter. For example, 3,834 records 

included a lithologic descriptor that allowed analysis of 

specific-capacity values by descriptor (fig. 6). The largest 

number of records were for wells in Maryland (fig. 9). 

Records for wells in Maryland and Pennsylvania were 88 

percent of the total.

Specific capacity, well yield, well depth, casing depth, 

and casing diameter were examined to describe the variation of numeric data contained in the well records 

(fig. 10). Of the specific-capacity values, 90 percent (5th to 

95th percentile) were between 0.02 and 27 (gal/min)/ft, a 

range that exceeds three orders of magnitude. The 

reported yields to half of the wells were 16 gal/min or 

less. The median depth of the wells was 166 ft; 95 percent 

of the wells were less than 476 ft deep, and only 5 percent 

of the wells were less than 57 ft deep. Half of the wells 

were cased to a depth of 41 ft or less. Of the casing diameters, 75 percent were 6 in. or less.

Primary use of the water and topographic setting 

were examined to describe the distribution of categorical 

data contained in the well records. With regard to primary use of the water, 63 percent of the wells were 

domestic; 18 percent were public or industrial supply; 

7 percent were commercial, institutional, or stock; and 

12 percent were used for other purposes or were unused. 

With regard to topographic setting, 58 percent of the 

wells were on hilltops or hillsides; 32 percent, in valley 

flats or flats; and 10 percent, in other or undesignated 

topographic settings. The data set predominantly consists of domestic wells on hilltops or hillsides.

Each well record was assigned to one of the five 

hydrogeologic terranes based on the identity of the geologic unit penetrated by the well. The geologic unit was 

the primary aquifer reported in the GWSI data base or, 

for those wells with no reported primary aquifer, was the 

geologic unit shown on State maps at the well location. 

The distribution of wells by hydrogeologic terrane was 

uneven. Most wells (3,324) were in the siliciclastic rock 

hydrogeologic terrane; the least number of wells (115) 

were in the alluvium hydrogeologic terrane. The dolomite, limestone, and argillaceous carbonate rock hydrogeologic terranes were the location for 1,334, 1,501, and 

617 wells, respectively.

Dependent and independent variables for analysis 

were selected primarily on the basis of earlier work by 

Knopman (1990, p. 3-6), who analyzed well records for 

Pennsylvania in the GWSI data base to identify factors 

that influence the water-yielding potential of the rock. 

Knopman used specific capacity as the dependent
35'

ALABAMA

PENNSYLVANIA

EXPLANATION

Boundary of study area of report

State line

Well used in analysis

TENNESSEE

100 MILES

100 KILOMETERS

ffi

DO O M 

O

5

O

oD 

TJ 

O H Mo

M

o

Base from U.S. Geological Survey 

1:2,500,000 scale map

FIGURE 9. Areal distribution of well records used in the analysis of well records. O
C18 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

NUMBER OF WELLS 

6,891

NUMBER OF WELLS 

6,889

1.UOU 

DC

z m

. . > 1 00

^~ t o

III 10

0 D. LJL

H w ° ' 

o z e

ftqo

Q- H O _ . w ^ u. 0.1

O

n m

O

^ I

r

r I

: ! 

o

l.UUU

w

z

3 ^ 100 

< ^

. oc

Q UJ i Qj D- in1U

1

0

I

I

o

NUMBER OF WELLS 

6,825

NUMBER OF WELLS 

6,012

BELOW DEPTH, IN FEET LAND SURFACE 1i s

0

I

! 1 i

FEET CASING DEPTH, IN BELOW LAND SURFACE

1§ 3O

 1 :

1 

O

o - 

z z

W 

< 

O

12

10

NUMBER OF WELLS 

6,358

75th, 

50th, 

25th, 

10th, 

5th

T

EXPLANATION

Percentile Indicates percentage of 

measurements equal to or less than 

indicated values

- 95th

- 90th

- 75th

- 50th

~ 25th

- 10th

- 5th

FIGURE 10. Variation of selected hydrologic and well-construction data for wells used in analysis.
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C19

variable; and used casing diameter, primary use of the 

water, lithologic descriptor, topographic setting, depth of 

casing, depth of well, saturated interval (as calculated 

from depth of well, static water level, and depth of casing), and primary aquifer (or geologic unit identifier) as 

independent variables. She determined that casing diameter, primary use of the water, lithologic descriptor, and 

topographic setting (in decreasing order) accounted for 

the most variation in specific-capacity values (Knopman, 

1990, p. 27, fig. 9).

The dependent variable for this study was specific 

capacity. Specific capacity and reported well discharge 

are measures of the yield of water to wells. Specific 

capacity was considered the more accurate measure 

because it accounts for drawdown in addition to discharge. As an example, a group of wells that produce an 

average 10 gal/min with 10 ft of drawdown are completed in rock that has better water-yielding properties 

than a group of wells that produce an average 

10 gal/min with 100 ft of drawdown. Specific capacity is 

only an approximate indicator of the water-yielding 

properties of the rock, because the consolidated rock in 

the study area commonly is neither isotropic nor homogeneous, and because the specific capacity varies with 

well discharge. Of the variables available for analysis, 

specific capacity nevertheless was considered to be the 

most accurate and abundant indicator.

The independent variables for this investigation casing diameter, primary use of the water, 

topographic setting, hydrogeologic terrane, and hydrogeologic terrane subdivision were selected on the basis 

of the results of work by three investigators in addition 

to Knopman (1990). Casing diameter correlated strongly 

with well diameter, which in turn was reported to correlate strongly with well yield; for example, average well 

yield was determined to be directly proportional to the 

diameter of wells in the Piedmont and Blue Ridge Physiographic Provinces of North Carolina (Daniel, 1989, 

p. A16-A20). In the present study, casing diameter was 

not postulated to directly influence specific capacity. A 

large part of the correlation between well diameter and 

yield (or specific capacity) is probably due to cultural 

bias in the siting and construction of the wells. This bias 

is associated with the intended use of the water and not 

with the greater discharge capacity of the larger casing 

size. For example, wells with a diameter greater than 

7 in. are likely to have been constructed at sites where a 

well owner who desired a large amount of water knew in 

advance that large quantities of water were available and 

warranted the expense of the larger casing size. Advance 

knowledge might be based on records of existing wells or 

the results of drilling test wells.

Concerning primary use of the water, Wood and 

MacLachlan (1978, p. 29-30, tables 5 and 6) provided 

data to show that the median specific-capacity values of 

nondomestic wells in carbonate geologic units are 

20 times the median values of domestic wells in the same 

units. A large part of the correlation between primary 

use of the water and specific capacity of wells is probably 

due to cultural bias in the siting and construction of the 

wells; for example, well owners who intend to withdraw 

water for public or industrial supply purposes usually 

are willing to invest more time and money on their water 

supplies than are well owners who intend to withdraw 

water for domestic purposes.

ANALYSIS OF RECORDS AND VARIABLES

Casing diameter, primary use of the water, and topographic setting influence the specific-capacity values of 

wells completed in the various hydrogeologic terranes. 

For example, when specific-capacity values for wells in 

the dolomite hydrogeologic terrane were grouped 

sequentially, first by categories of the variable casing 

diameter, then by categories of primary use of the water, 

and last by categories of topographic setting (fig. 11), 

substantial differences became apparent. For the dolomite hydrogeologic terrane, wells with casing diameters 

of less than 7 in. generally had a smaller specific capacity 

than wells with casing diameters of greater than 9 in. 

Wells used for domestic supply typically had a smaller 

specific capacity than wells used for public or industrial 

supply, and wells located on hills had a smaller specific 

capacity than wells located in valleys (fig. 11). The eight 

categories within the three variables (fig. 11) had similar 

relations to specific-capacity values for wells completed 

in the four other hydrogeologic terranes.

To further examine the apparent differences in 

specific-capacity values among the categories of the 

variables casing diameter, primary use of the water, and 

topographic setting, Tukey's honestly significant difference test (SAS Institute, Inc., 1985, p. 473) was employed. 

Tukey's test, a nonparametric statistical procedure, was 

used to determine if the apparent differences in median 

values among these categories were statistically significant from each other. The test involves a null hypothesis that no real differences in median values of specific 

capacity exist among wells in the various categories. 

An alpha level, or level of probability, is used in the 

test to represent the maximum probability of rejecting 

the null hypothesis when it is actually true. Tukey tests 

performed at a probability (alpha level) of 0.01 indicated a statistically significant difference between the 

median values of specific capacity for the following 

seven pairs of categories within the three variables
C20 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

1,000

NUMBER OF WELLS

837 168 255 503 101 427 552 591

O

2

DC 

LU 

CL 

LU

CO O

Z Q

O g: =!< 

< K S o

-, LL

^ O

o 

o

o

LU 

CL 

CO

100

10

0.1

0.01

CATEGORY

0

r 

o

M

-

:

.

;

-

"

O

r O

0

CO CO LU Z CO 

LU LU > < LU I I to x I 

o QO i-o 

z zij cc z

z z !<

< Z LU

O

°I

-i0

o

0

9

o p £ < °^z<

CO O < DC 

LiJ DC >- \- 

^ LU 1 CO

1 8 ! «- 11 

0

0

;

1

-

-

;

-

~

-

O j 

0

_l >.

 1 LJJ 

X 1

CD

VARIABLE

w co ^ l^-

LU

_l

I

V 

CASING 

DIAMETER

CD

CL 

1 J

¥ 

PRIMARY USE 

OF THE WATER

J

Y 

TOPOGRAPHIC

SETTING

EXPLANATION

Percentile Indicates percentage of measurements 

equal to or less than indicated values

95th 

90th 

75th

50th

25th

10th

5th

FIGURE 11. Variation of specific-capacity values for wells in the dolomite 

hydrogeologic terrane grouped by categories of well-casing diameter, primary 

use of the water, and topographic setting of the well.

[where (less than 7 in.)/(7 to 9 in. inclusive) is an example of a single pair] (fig. 11):

Casing diameter

(less than 7 in.)/(7 to 9 in. inclusive) 

(less than 7 in.)/(greater than 9 in.) 

(7 to 9 in. inclusive)/(greater than 9 in.)

Primary use of the water

(domestic) / (commercial) 

(domestic)/(public and industrial supply) 

(commercial)/(public and industrial supply)

Topographic setting

(hill)/(valley).

Differences among the hydrogeologic terranes in 

regard to the percentage of wells in each category of the 

three variables tend to bias the median values of specific 

capacity and complicate the determination of significant 

differences in water-yielding properties among the 

hydrogeologic terranes. For example, the alluvium 

hydrogeologic terrane has a larger percentage of wells 

with casing diameters of greater than 9 in. than does the 

dolomite hydrogeologic terrane. This difference between 

the two hydrogeologic terranes tends to exaggerate the 

apparent difference between their median values of specific capacity. Testing for significant differences in wateryielding properties between the alluvium and dolomite 

hydrogeologic terranes may not be valid without 

accounting for differences between data sets in regard to 

casing diameter.

A method for reducing the influence of casing diameter, primary use of the water, and topographic setting on 

specific capacity is to subdivide the data base into homogeneous data sets consisting of wells with the same characteristics with respect to these three variables. Two 

homogeneous data sets were constructed for each hydrogeologic terrane the most-productive wells and the 

least-productive wells (fig. 12). The homogeneous data 

set that represented the most-productive wells consisted 

only of wells with casing diameters of greater than or 

equal to 7 in., used for either public or industrial supply, 

and located in valleys. The homogeneous data set that 

represented the least-productive wells consisted only of 

wells with casing diameters of less than 7 in., used for 

domestic supply, and located on hills. The influence of 

these variables is so pronounced that the interquartile 

range (25th to 75th percentile) for the most-productive 

wells in siliciclastic rock does not even overlap the interquartile range for the least-productive wells in dolomite 

(ng. 12)

Specific-capacity values for these two homogeneous 

data sets for each hydrogeologic terrane are significantly 

different according to Tukey tests probability (alpha 

level) of 0.0005. Subdividing the data into homogeneous
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C21

NUMBER OF WELLS

1,000

oLL

£ 100

o.

LU

H

Z

GALLONS PERMlIN 

OF DRAWDOWN

O-L 

O

o

8 0.1

0 

LU 

D_ 

CO

0.01

HYDROGEC 

TE

34 195 66 26 91 

6 268 583 274 1,655

: I I I I I :

J _

r-J i 1

~ 

i 1 '

T 1

r rn IL-T -rt i

" n :

; -r- ¥ P T '-

, TT~ T ;

1 I 1 l I

^ LU LU COLU^i O^ D t- z ^bo i=o 

XOGIC > i 0 2ig|g 

RRANE 3 3 M oO"-3

 7^ LU < CD Q

< § i 3^ o

-1 a " =! 

cc co

EXPLANATION

Description of homogeneous data sets Most-productive wells data set 

consists only of wells with casing diameters of greater than or equal to 

7 in., used for either public or industrial supply, and located in valleys. 

Least-productive wells data set consists only of wells with casing 

diameters less than 7 in., used for domestic supply, and located on hills.

Percentile Indicates percentage of measurements 

equal to or less than indicated values

T~

90th 

75th

50th 

25th 

10th

34 Number of most-productive wells 

6 Number of least-productive wells

Boxplot of most-productive wells 

Boxplot of least-productive wells

FIGURE 12. Variation of specific-capacity values for wells grouped by five hydrogeologic terranes 

and two homogeneous data sets.
C22 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

sets (fig. 12) revealed some of the cause for the large 

range in values within each hydrogeologic terrane for 

undivided data sets that results in overlapping values 

between terranes. The homogeneous data sets represent 

end members in a range of values wherein restrictions 

were made on the three variables casing diameter, primary use of the water, and topographic setting. In contrast, when no restrictions were made on these variables 

as for nonhomogeneous, undivided sets, the range in 

specific-capacity values for each hydrogeologic terrane 

was sufficiently large that real differences among terranes were obscured, and the range in values for each 

hydrogeologic terrane had substantial overlap with the 

range of other terranes. Subdividing the data base by the 

three variables allows for better estimates of the specific 

capacity of the hydrogeologic terranes.

Valid conclusions about significant differences in 

water-yielding properties can be made by comparing subdivided data sets. Concerning a comparison of median 

specific-capacity values for most-productive wells, Tukey 

test results indicated a statistically significant difference probability (alpha level) of 0.05 between median 

values for the following pairs of hydrogeologic terranes:

(alluvium) / (limestone), 

(alluvium)/(argillaceous carbonate rock), 

(alluvium)/(siliciclastic rock), 

(dolomite) / (limestone), 

(dolomite)/ (argillaceous carbonate rock), 

(dolomite)/(siliciclastic rock), 

(limestone)/(siliciclastic rock), and 

(argillaceous carbonate rock)/(siliciclastic rock).

Tukey test results did not indicate a statistically significant difference between median values of specific capacity for the remaining two pairs of hydrogeologic terranes 

at a probability (alpha level) of 0.05:

(alluvium)/(dolomite), and

(limestone)/(argillaceous carbonate rock).

In summary Tukey test results indicated that the differences in median specific-capacity values were significant for at least 8 of the 10 pairs of hydrogeologic 

terranes by use of homogeneous data sets. Therefore, the 

hydrogeologic terranes are, for the most part, significantly different in their water-yielding properties.

ANALYSIS OF HYDROGEOLOGIC TERRANE 

SUBDIVISIONS

A statistical analysis of well records was performed to 

determine if significant differences in water-yielding 

properties between subdivisions of the dolomite hydrogeologic terrane could be detected. To determine

differences between the western toe subdivision of the 

dolomite hydrogeologic terrane and remaining subdivisions of this terrane, a comparison was made using 

44 records of the most-productive wells from the GWSI 

data base of the USGS for Virginia and West Virginia. For 

the purpose of this comparison, wells located within the 

dolomite hydrogeologic terrane and within a band that is 

3 mi wide along the southeastern border of the Valley 

and Ridge Physiographic Province in these two States 

were classified as "in-toe" wells, and those within the 

dolomite hydrogeologic terrane to the northwest were 

classified as "out-of-toe" wells. The ranges of the middle 

90 percent of specific-capacity values overlapped and 

spanned about three orders of magnitude (fig. 13). The 

median specific-capacity value for "in-toe" wells 

[26 (gal/min)/ft] is more than three times the median 

value for "out-of-toe" wells [7.2 (gal/min)/ft].

To further examine the apparent differences in 

specific-capacity values between the subdivisions of the 

dolomite hydrogeologic terrane, a nonparametric statistical procedure, the Mann-Whitney test (Inman and 

Conover, 1983, p. 281) was employed. The MannWhitney test was used to determine if the apparent differences in median values between these subdivisions 

were statistically significant from each other. The MannWhitney test involves a null hypothesis that no real difference in median values of specific capacity exist 

between wells in the two subdivisions. An alpha value, 

or level of probability, is used in the test to represent the 

maximum probability of rejecting the null hypothesis 

when it is actually true. The alpha value used in this 

analysis was 0.05. The p-value represents the attained 

level of significance determined from the data using the 

Mann-Whitney test. If the p-value is less than or equal to 

the alpha value, the null hypothesis is rejected, and significant differences are assumed to exist between the 

subdivisions.

The Mann-Whitney test indicated a statistically significant difference between the median values of specific 

capacity for the subdivisions of the dolomite hydrogeologic terrane in Virginia and West Virginia (p-value of 

0.05). Public and industrial supply wells in dolomite in 

the western toe had significantly greater specific-capacity 

values than comparable wells in dolomite elsewhere in 

Virginia and West Virginia.

POTENTIAL YIELD OF WATER TO WELLS

The potential rate that water can be withdrawn from 

public and industrial supply wells can be estimated from 

the reported specific-capacity values of the mostproductive wells (fig. 12) by assuming constant drawdowns for each hydrogeologic terrane and negligible
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C23

1,000 F

NUMBER OF WELLS 

16 28

CC 

HI 

D_ 

HI 100

coo

ZO

<cc 

go

10

O 

O

O 111

D_ 

CO

0.1

001

1

T

HI

O

O

LLJ 

O

O

T

EXPLANATION

Percentile Indicates percentage of measurements 

equal to or less than indicated values

95th 

90th 

75th

50th

25th

10th

5th

FIGURE 13. Variation of specific-capacity values for public and 

industrial supply wells in and out of the western toe subdivision 

of the dolomite hydrogeologic terrane in Virginia and West 

Virginia.

well-entrance losses. These constant drawdowns were 

determined from the median of reported drawdowns for 

the most-productive wells. For these wells, the median 

drawdowns (rounded to the nearest 10 ft) were 10 ft, 

alluvium; 30 ft, dolomite and limestone; 50 ft, argillaceous carbonate rock; and 90 ft, siliciclastic rock. As an 

example of the calculation of potential yield, the median 

specific capacity of the 91 most-productive wells in siliciclastic rock (fig. 12) was 1.4 (gal/min)/ft. When multiplied by 90 ft of drawdown, this specific-capacity value 

resulted in an estimated median potential yield of about 

130 gal/min (fig. 14). Because the water-yielding properties of the rock vary, a more realistic estimate of potential 

yield is given by the interquartile range in specific capacity. On the basis of data for the 412 most-productive 

wells, the middle 50-percent range in estimated potential 

yields to these public and industrial supply wells was 

170 to 580 gal/min, alluvium; 210 to 1,400 gal/min, dolomite; 80 to 720 gal/min, limestone; 65 to 850 gal/min, 

argillaceous carbonate rock; and 70 to 280 gal/min, siliciclastic rock (fig. 14).

SUMMARY

This report provides information on the hydrogeologic setting of the Valley and Ridge Physiographic Province, describes and maps hydrogeologic terranes within 

this setting, applies statistical tests to these hydrogeologic terranes to identify significant differences in water 

yielding properties, and estimates the quantity of water 

potentially available to public and industrial supply 

wells in these hydrogeologic terranes.

The Valley and Ridge Physiographic Province is 

underlain by deformed sedimentary rock of Paleozoic 

age including dolomite, limestone, shale, and sandstone. 

Regolith (soil, sediment, and weathered rock) covers the 

Paleozoic rock throughout most of the province. Ground 

water in the consolidated sedimentary rock resides in 

and flows through secondary opening. Flow systems 

tend to be limited in depth by weathering and associated 

enhancement of secondary permeability and limited in 

areal extent by faults and folds and stream drainage networks. The largest flow systems discharge at springs in 

carbonate rock. Selected rock types account for a substantial part of the variation in the water-yielding properties of the rock because of the unique way in which 

these rock types deform and weather. Structure also 

accounts for some of the variation because faults juxtapose rock types with different water-yielding properties; 

and joints, fractures, and bedding-plane partings are a 

variable network of openings for ground-water movement. Well-sorted alluvium of glacial origin in the northeastern one-fifth of the area, and regolith along the
C24 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

NUMBER OF WELLS

100,000

LUIB 10,000

z

cc

LU 

Q_

C/D

1,000

34 195 66 26 91

CD

z

3

LU

o

Q_

100

10

HYDROGEOLOGIC ^

§

ill 

z

§|s

31

o * j= o

8

EXPLANATION

Description of most-productive wells Most-productive wells data set 

consists only of wells with casing diameters of greater than or equal to 

7 in., used for either public or industrial supply, and located in valleys.

Calculation of potential yield Potential yield is estimated by multiplying 

specific capacity shown in figure 12 for most-productive wells by a 

median drawdown of 10 ft, alluvium; 30 ft, dolomite and limestone; 

50 ft, argillaceous carbonate rock; and 90 ft, siliciclastic rock

Percentile Indicates percentage of estimates 

equal to or less than indicated values

90th 

75th

50th 

25th 

10th

FIGURE 14. Variation of estimated potential yield of water to most-productive wells in hydrogeologic 

terranes in the Valley and Ridge Physiographic Province in the Eastern and Southeastern United States.
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C25

southeastern edge of the Valley and Ridge Physiographic 

Province, store large quantities of ground water.

Hydrogeologic terranes are regionally mappable 

areas characterized by similar rock type and wateryielding properties; areas of a particular rock type and 

water-yielding properties were assigned to a particular 

terrane to help water users in locating and developing 

adequate water supplies. The five hydrogeologic terranes 

defined in the report alluvium, dolomite, limestone, 

argillaceous carbonate rock, and siliciclastic rock were 

defined based on the relation of rock type to the nature of 

water-yielding openings and water-yielding properties 

as indicated by the specific capacity of wells. Consolidated sedimentary rock units, which were identified 

from State geologic maps, and the regolith were grouped 

into the hydrogeologic terranes on the basis of the predominant lithology of mapped geologic units. Maps 

showing the distribution of the hydrogeologic terranes in 

the study area were compiled from the same State geologic maps. The hydrogeologic terranes coincide with the 

outcrop of the geologic units that have the corresponding 

predominant lithology. The siliciclastic rock hydrogeologic terrane includes most of the study area. The western toe of the Blue Ridge Mountains subdivision of the 

dolomite hydrogeologic terrane is along the southeastern 

edge of the Valley and Ridge Physiographic Province 

where siliciclastic rock debris from the adjacent highlands covers thick residuum and dolomite. The western 

toe has wells that produce more than 1,000 gal/min.

To determine if significant differences in wateryielding properties among the hydrogeologic terranes 

could be detected, records for wells with 6,891 specificcapacity values were retrieved from the GWSI data base 

for the study area. These data were predominantly for 

domestic wells on hilltops and hillsides. Building on previous investigations, the authors selected specific capacity as the variable that best represents the water-yielding 

properties of the hydrogeologic terranes in the study 

area. Casing diameter, primary use of the water, topographic setting, hydrogeologic terrane, and hydrogeologic terrane subdivision were selected as variables that 

influence the value of specific capacity.

Casing diameter, primary use of the water, and topographic setting influence specific-capacity values of wells 

completed in each hydrogeologic terrane. Homogeneous 

data sets, which consist of all wells that have the same 

characteristics with respect to casing diameter, primary 

use of the water, and topographic setting, however, take 

these three variables into account and allow valid conclusions regarding significant differences in water-yielding 

properties. All five hydrogeologic terranes showed differences. According to results of Tukey statistical tests at 

a probability (alpha level) of 0.05, 8 out of 10 pairs of 

hydrogeologic terranes had significantly different

median specific-capacity values by using homogeneous 

data sets. The median specific-capacity value for public 

and industrial supply wells in the western toe subdivision of the dolomite hydrogeologic terrane is more than 

three times the value for comparable wells in the rest of 

the dolomite hydrogeologic terrane in Virginia and West 

Virginia a significant difference.

Estimates of potential yields to public and industrial 

supply wells were calculated from specific-capacity data 

for the most-productive wells, which have casing diameter of 7 in. or more, discharge water primarily for public 

or industrial supply, and are in a valley. Median constant 

drawdowns, calculated from reported drawdowns, were 

determined to be between 10 and 90 ft for wells completed in each of the five hydrogeologic terranes, and 

well-entrance losses were assumed to be negligible. Estimated interquartile ranges in potential yields to 412 mostproductive wells in the five hydrogeologic terranes were 

170 to 580 gal/min, alluvium; 210 to 1,400 gal/min, dolomite; 80 to 720 gal/min, limestone; 65 to 850 gal/min, 

argillaceous carbonate rock; and 70 to 280 gal/min, 

siliciclastic rock.

SELECTED REFERENCES

Bailey, Z.C., and Lee, R.W., 1991, Hydrogeology and geochemistry in 

Bear Creek and Union Valleys, near Oak Ridge, Tennessee: U.S. 

Geological Survey Water-Resources Investigations Report 

90-4008, 72 p.

Becher, A.E., and Root, S.I., 1981, Groundwater and geology of the

Cumberland Valley, Cumberland County, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water Resource Report 50, 95 p.

Becher, A.E., and Taylor, L.E., 1982, Groundwater resources in the Cumberland and contiguous valleys of Franklin County, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water Resource 

Report 53, 67 p.

Berg, T.M., Edmunds, WE., Geyer, A.R., and others, comps., 1980, Geologic map of Pennsylvania: Pennsylvania Geological Survey, 4th 

ser., Map 1, 3 sheets, scale 1:250,000.

Berg, T.M., Way, J.H., and Mclnerney, M., 1985, South-central Pennsylvania, column 18, southeastern Pennsylvania, column 19, and 

eastern Pennsylvania, column 24, in Patchen, D.G., Avary, K.L., 

and Erwin, R.B., regional coords.. Correlation of stratigraphic 

units of North America (COSUNA) project Northern Appalachian region: American Association of Petroleum Geologists, 

1 sheet.

Bieber, P.P., 1961, Ground-water features of Berkeley and Jefferson

Counties, West Virginia: West Virginia Geological and Economic 

Survey Bulletin 21, 81 p.

Bossong, C.R., 1989, Geohydrology and susceptibility of major aquifers 

to surface contamination in Alabama; area 2: U.S. Geological Survey Water-Resources Investigations Report 88-4177, 22 p.

Bradfield, A.D., 1992, Hydrology of the Cave Springs area near Chattanooga, Hamilton County, Tennessee: U.S. Geological Survey 

Water-Resources Investigations Report 92-4018,28 p.

Bradley, M.W, and Hollyday, E.F., 1985, Tennessee ground-water

resources, in National water summary 1984 Hydrologic events, 

selected water-quality trends, and ground-water resources: U.S. 

Geological Survey Water-Supply Paper 2275, p. 391-396.
C26 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

Brahana, J.V., and Hollyday, E.F., 1988, Dry stream reaches in carbonate 

terranes: Surface indicators of ground-water reservoirs: American 

Water Resources Association Water Resources Bulletin, v. 24, 

no. 3, p. 577-580.

Brahana, J.V., Mulderink, Dolores, Macy, J.A., and Bradley, M.W, 1986, 

Preliminary delineation and description of the regional aquifers 

of Tennessee The East Tennessee aquifer system: U.S. Geological 

Survey Water-Resources Investigations Report 82-4091, 30 p.

Brent, W.B., 1960, Geology and mineral resources of Rockingham

County: Virginia Division of Mineral Resources Bulletin 76,174 p.

Broshears, R.E., 1988, Tennessee ground-water quality, in National 

water summary 1986 Hydrologic events and ground-water 

quality: U.S. Geological Survey Water-Supply Paper 2325, 

p. 465-472.

Butts, Charles, 1910, Description of the Birmingham quadrangle, Alabama: U.S. Geological Survey Atlas, Folio 175.

 1927, Description of the Bessemer-Vandiver quadrangles, Alabama: U.S. Geological Survey Atlas, Folio 226.

 1933, Geologic map of the Appalachian Valley of Virginia with 

explanatory text: Virginia Division of Mineral Resources, Virginia 

Geological Survey Bulletin 42, 56 p., 1 sheet, scale 1:250,000. 

-1940, reprint 1973, Geology of the Appalachian Valley in Virginia: Virginia Division of Mineral Resources, Virginia Geological 

Survey Bulletin 52, pt. 1, 568 p.

Cady, R.C., 1933, Preliminary report on ground-water resources of 

northern Virginia: Virginia Geological Survey Bulletin 41, 48 p.

Cady, R.C., and Lohr, E.W, 1936, Ground-water resources of the 

Shenandoah Valley, Virginia: Virginia Geological Survey 

Bulletin 45,137 p.

Callahan, J.T., 1958, Large springs in northwestern Georgia: Georgia 

Mineral Newsletter, v. 11, no. 3, p. 80-86.

Calver, J.L., and Hobbs, C.R.B., eds., 1963, Geologic map of Virginia: 

Virginia Division of Mineral Resources map, 1 sheet, 

scale 1:500,000.

Cardwell, D.H., Erwin, R.B., and Woodward, H.P., comps., 1968, Geologic map of West Virginia: West Virginia Geological and Economic Survey map, 2 sheets, scale 1:250,000.

Carswell, L.D., and Lloyd, O.B., 1979, Geology and groundwater

resources of Monroe County, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water Resources Report 47, 61 p.

Causey, L.V, 1961a, Geologic map of Etowah County, Alabama: Geological Survey of Alabama Special Map 15.

 1961b, Ground-water resources of Etowah County, Alabama Reconnaissance report: Geological Survey of Alabama 

Information Series 25.

 1963a, Generalized geologic maps of St. Clair County, Alabama: 

Geological Survey of Alabama Special Map 21.

 1963b, Geology and ground-water resources of St. Clair County, 

Alabama: Geological Survey of Alabama Bulletin 73.

 1965a, Geologic map of Cherokee County, Alabama: Geological 

Survey of Alabama Special Map 39. 

-1965b, Geologic rock-type map of Talladega County, Alabama:

Geological Survey of Alabama Special Map 38.

 1965c, Geology and ground-water resources of Cherokee

County, Alabama A reconnaissance: Geological Survey of Alabama Bulletin 79.

 1965d, Availability of ground water in Talladega County, Alabama A reconnaissance: Geological Survey of Alabama 

Bulletin 81.

Causey, L.V., Willmon, J.R., and Ellard, J.S., 1975, Water availability in 

Bibb County, Alabama: U.S. Geological Survey unnumbered 

open-file report.

 1978, Water availability in Bibb County, Alabama: Geological 

Survey of Alabama Special Map 144.

Cederstrom, D.J., Boswell, E.H., and Tarver, G.H., 1978, Summary 

appraisals of the Nation's ground-water resources South 

Atlantic-Gulf Region: U.S. Geological Survey Professional 

Paper 813-O, 35 p.

Chisholm, J.L., and Frye, P.M., 1976, Records of wells, springs, chemical 

analyses of water, biological analyses of water, and standard 

streamflow data summaries from the upper New River basin in 

West Virginia: West Virginia Geological and Economic Survey 

Basic Data Report 4, 78 p.

Clark, WE., Chisholm, J.L., and Frye, P.M., 1976, Water resources of the 

upper New River basin, West Virginia: West Virginia Geological 

and Economic Survey River Basin Bulletin 4, 87 p.

Cleaves, E.T., Edwards, Jonathan, Jr., and Glaser, J.D., comps., 1968, 

Geologic map of Maryland: Maryland Geological Survey map, 

1 sheet, scale 1:250,000.

Cloos, Ernst, 1951, Stratigraphy and sedimentary rocks of Washington 

County, in The physical features of Washington County: Maryland Department of Geology, Mines and Water Resources, 

p. 17-94.

Collins, W.D., Foster, M.D., Reeves, Frank, and Meacham, R.P., 1930, 

Springs of Virginia: Virginia Division of Water Resources and 

Power Bulletin 1, 55 p.

Colton, G.W., 1970, The Appalachian basin Its depositional sequences 

and their geologic relationships, in Fisher, G.W, Pettijohn, F.J., 

Reed, J.C., and Weaver, K.N., eds., Studies of Appalachian geology Central and southern: New York, Wiley, 460 p., p. 5-47.

Cooper, B.N., 1966, Geology of the salt and gypsum deposits in the

Saltville area, Smyth and Washington Counties, Virginia, in Geology, chemistry, and mining, v. 1, Second symposium on salt: 

Cleveland, Ohio, Northern Ohio Geological Society, p. 11-35.

Copeland, C.W, and Raymond, D.E., 1985, DeKalb and western

Etowah Counties, Alabama, column 4, Western Valley and Ridge, 

northern segment, column 5, Eastern Valley and Ridge, northern 

segment, Alabama, column 6, Western Valley and Ridge, southern 

segment, column 7, and Eastern Valley and Ridge, southern segment, column 8, in Patchen, D.G., Avary, K.L., and Erwin, R.B., 

regional coords., Correlation of stratigraphic units of North 

America (COSUNA) project Southern Appalachian region: 

American Association of Petroleum Geologists, 1 sheet.

Cressler, C.W, 1963, Geology and ground-water resources of Catoosa 

County, Georgia: Georgia Department of Natural Resources Information Circular 28.

 1964a, Geology and ground-water resources of the Paleozoic 

rock area, Chattooga County, Georgia: Georgia Department of 

Natural Resources Information Circular 27.

 1964b, Geology and ground-water resources of Walker County, 

Georgia: Georgia Department of Natural Resources Information 

Circular 29.

 1970, Geology and ground-water resources of Floyd and Polk

Counties, Georgia: Georgia Department of Natural Resources

Information Circular 39.

-1974, Geology and ground-water resources of Gordon, Whitfield, and Murray Counties, Georgia: Georgia Department of Natural Resources Information Circular 47.

Cressler, C.W, Blanchard, H.E., Jr., and Hester, W.G., 1979, Geohydrology of Bartow, Cherokee, and Forsyth Counties, Georgia: Georgia 

Department of Natural Resources Information Circular 50.

Cressler, C.W, Franklin, M.A., and Hester, W.G., 1976, Availability of 

water supplies in northwest Georgia: Georgia Department of Natural Resources, Geologic and Water Resources Division 

Bulletin 91,140 p.

Croft, M.G., 1963, Geology and ground-water resources of Bartow 

County, Georgia: U.S. Geological Survey Water-Supply 

Paper 1619-FF, 32 p.
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C27

 1964, Geology and ground-water resources of Dade County, 

Georgia: Georgia Department of Natural Resources Information 

Circular 26.

Dalton, Richard, and Markawicz, F.J., 1985, Northwestern New Jersey, 

column 25, in Patchen, D.G., Avary, K.L., and Erwin, R.B., regional 

coords., Correlation of stratigraphic units of North America 

(COSUNA) project Northern Appalachian region: American 

Association of Petroleum Geologists, 1 sheet.

Daniel, C.C., III, 1989, Statistical analysis relating well yield to construction practices and siting of wells in the Piedmont and Blue Ridge 

Provinces of North Carolina: U.S. Geological Survey WaterSupply Paper 2341-A, 27 p.

Daniel, C.C., III, and Payne, R.A., 1990, Hydrogeologic unit map of the 

Piedmont and Blue Ridge Provinces of North Carolina: U.S. Geological Survey Water-Resources Investigations Report 90-4035, 

1 sheet, scale 1:500,000.

DeBuchananne, G.D., and Richardson, R.M., 1956, Ground-water

resources of East Tennessee: Tennessee Division of Geology Bulletin 58, pt. 1,393 p.

Dekay, R.H., 1972, Development of ground-water supplies in Shenandoah National Park, Virginia: Virginia Division of Mineral 

Resources, Mineral Resources Report 10,158 p.

Diecchio, R.J., 1985, Post-Martinsburg Ordovician stratigraphy of Virginia and West Virginia: Virginia Division of Mineral Resources 

Publication 57',77 p.

Drake, A.A., Jr., 1965, Carbonate rocks of Cambrian and Ordovician 

age, Northampton and Bucks Counties, eastern Pennsylvania, 

and Warren and Hunterdon Counties, western New Jersey: U.S. 

Geological Survey Bulletin 1194-L, p. L1-L7.

Drake, A.A., Jr., and Lyttle, P.T., 1980, Alleghanian thrust faults in the 

Kittatinny Valley, New Jersey, in Manspeizer, Warren, ed., Field 

studies of New Jersey geology and guide to field trips: Newark, 

New Jersey, Rutgers University Press, p. 92-114.

Duigon, M.T., and Dine, J.R., 1991, Water resources of Washington 

County: Maryland Geological Survey Bulletin 36,109 p.

Duigon, M.T., Dine, J.R., and Tompkins, M.D., 1989, Ground-water and 

surface-water data for Washington County, Maryland: Maryland 

Geological Survey Basic Data Report No. 18, 273 p.

Edwards, Jonathan, Jr., 1978, Geologic map of Washington County: 

Maryland Geological Survey map, 1 sheet, scale 1:62,500.

Epstein, J.B., and Epstein, A.G., 1969, Geology of the Valley and Ridge 

Province between Delaware Water Gap and Lehigh Gap, Pennsylvania, Field trip 1-B, in Subitzky, Seymour, ed., Geology of 

selected areas in New Jersey and eastern Pennsylvania and guidebook of excursions: New Brunswick, New Jersey, Rutgers University Press, p. 132-205.

Evaldi, R.D., and Lewis, J.G., 1983, Base flow and ground water in 

upper Sweetwater Valley, Tennessee: U.S. Geological Survey 

Water-Resources Investigations Report 83-4068, 30 p.

Faust, R.J., and Harkins, J.R., 1980, Water availability, Blount County, 

Alabama: Geological Survey of Alabama Special Map 141,19 p.

Fenneman, N.M., 1938, Physiography of Eastern United States: New 

York, McGraw-Hill, 714 p.

Freeze, R.A., and Cherry, J.A., 1979, Groundwater: Englewood Cliffs, 

N.J., Prentice-Hall, 604 p.

Friel, E.A., Hobba, W.A., Jr., Chisholm, J.L., 1975, Records of wells, 

springs, and streams in the Potomac River basin, West Virginia: 

West Virginia Geological and Economic Survey Basic Data 

Report 3, 96 p.

Gaydos, M.W., and others, 1982, Hydrology of area 19, eastern coal 

province, Tennessee: U.S. Geological Survey Water-Resources 

Investigations Report 81-901, 75 p.

Gerhart, J.M., and Lazorchick, G.J., 1984, Evaluation of the groundwater resources of parts of Lancaster and Berks Counties, Pennsylvania: U.S. Geological Survey Water-Resources Investigations

Report 84-4327,136 p.

-1988, Evaluation of the ground-water resources of the lower Susquehanna River basin, Pennsylvania and Maryland: U.S. Geological Survey Water-Supply Paper 2284,128 p.

Glaser, J.D., 1985, Allegany County, Maryland, column 13, and Washington County, Maryland, column 14, in Patchen, D.G., Avary, 

K.L., and Erwin R.B., regional coords., Correlation of stratigraphic 

units of North America (COSUNA) project Northern Appalachian region: American Association of Petroleum Geologists, 

1 sheet.

Hack, J.T., 1965, Geomorphology of the Shenandoah Valley, Virginia 

and West Virginia, and origin of the residual ore deposits: U.S. 

Geological Survey Professional Paper 484, 84 p.

Hartford, C.R., 1978, Monteagle Limestone (Upper Mississippian)

oolitic tidal-bar sedimentation in southern Cumberland Plateau: 

American Association of Petroleum Geologists Bulletin, v. 62, 

no. 4, p. 644-656.

Hardeman, W.D., 1966, Geologic map of Tennessee: Tennessee Division 

of Geology map, 4 sheets, scale 1:250,000.

Harkins, J.R., and others, 1982, Hydrology of area 24, eastern coal province, Alabama: U.S. Geological Survey Open-File Report 81-1113, 

81 p.

Hinkle, K.R., and Sterrett, R.McC, 1976, Rockingham County groundwater Present conditions and prospects: Virginia Water Control 

Board Planning Bulletin 300, 88 p.

 1978, Groundwater resources of Augusta County, Virginia: Virginia Water Control Board Planning Bulletin 310,119 p.

Hobba, W.A., Jr., 1976, Ground-water hydrology of Berkeley County, 

West Virginia: West Virginia Geological and Economic Survey 

report, 21 p.

 1981, Ground-water hydrology of Jefferson County, West Virginia: West Virginia Geological and Economic Survey Environmental Geology Bulletin EGB-16, 21 p.

 1985, Water in Hardy, Hampshire, and western Morgan Counties, West Virginia: West Virginia Geological and Economic Survey Environmental Geology Bulletin EGB-19, 91 p.

-1988, Progress report on the ground-water study in Jefferson

County, West Virginia, March 1988: U.S. Geological Survey OpenFile Report 88-188, 3 p.

Hobba, W.A., Jr., Fisher, D.W, Pearson, F.J., Jr., and Chemerys, J.C., 

1979, Hydrology and geochemistry of thermal springs of the 

Appalachians: U.S. Geological Survey Professional Paper 1044-E, 

36 p.

Hobba, W.A., Jr., Friel, E.A., and Chisholm, J.L., 1972, Water resources 

of the Potomac River basin, West Virginia: West Virginia Geological and Economic Survey River Basin Bulletin 3,110 p.

 1973, Ground-water hydrology of the Potomac River basin, 

West Virginia: West Virginia Geological and Economic Survey 

Hydrologic Map, 1 sheet, scale 1:250,000.

Hobson, J.P., Jr., 1963, Stratigraphy of the Beekmantown Group in 

southeastern Pennsylvania: Pennsylvania Geological Survey, 

4th ser., General Geology Report G37, 331 p.

Hollowell, J.R., 1971, Hydrology of the Pleistocene sediments in the 

Wyoming Valley, Luzerne County, Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., Water Resource Report 28, 77 p.

Hollowell, J.R., and Coaster, H.E., 1975, Ground-water resources of

Lackawanna County, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water Resource Report 41,106 p.

Hollyday, E.F., and Goddard, PL., 1980, Ground-water availability in 

carbonate rocks of the Dandridge area, Jefferson County, Tennessee: U.S. Geological Survey Water-Resources Investigations 

Report 79-1236,50 p.

Hollyday, E.F., Hileman, G.E., Smith, M.A., and Pavlicek, D.J., 1996, 

Hydrogeologic terranes and potential yield of water to wells in
C28 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

the Valley and Ridge Physiographic Province in Maryland, New 

Jersey, and Pennsylvania: U.S. Geological Survey Hydrologic 

Investigations Atlas HA-732-A, 2 sheets, scale 1:500,000.

Hollyday, E.F., Knopman, D.S., Smith, M.A., and Hileman, G.E., 1992, 

Statistical analysis of well records for use in classifying and mapping hydrogeologic terranes in the Valley and Ridge Province, in 

Hotchkiss, W.R. and Johnson, A.I., eds., Regional aquifer systems 

of the United States Aquifers of the southeastern area: American 

Water Resources Association Monograph Series 17,18 p.

Hollyday, E.F., and others, 1983, Hydrology of area 20, eastern coal

province, Tennessee, Georgia and Alabama: U.S. Geological Survey Water-Resources Investigations Report 82-440, 81 p.

Hollyday, E.F., and Smith, M.A., 1990, Large springs in the Valley and 

Ridge Province in Tennessee: U.S. Geological Survey WaterResources Investigations Report 89-4205, 9 p.

Hubbard, D.A., Jr., 1990, Geologic map of Clarke County, Virginia; map 

of hydrogeologic components for Clarke County, Virginia: Virginia Division of Mineral Resources Publication 102, 2 sheets, 

scale 1:50,000.

Hufschmidt, P.W, and others, 1981, Hydrology of area 16, eastern coal 

province, Virginia and Tennessee: U.S. Geological Survey WaterResources Investigations Report 81-204, 68 p.

Inman, R.L., and Conover, W.J., 1983, A modern approach to statistics: 

New York, Wiley, 497 p.

Johnston, W.D., Jr., 1933, Ground water in the Paleozoic rocks of northern Alabama: Geological Survey of Alabama Special Report 16, 

414 p.

Jones, W.K., 1973, Hydrology of limestone karst in Greenbrier County, 

West Virginia: West Virginia Geological and Economic Survey 

Bulletin 36, 49 p.

Kidd, R.E., 1989, Geohydrology and susceptibility of aquifers to surface 

contamination in Alabama; area 5: U.S. Geological Survey WaterResources Investigations Report 88-4083, 28 p.

King, P.B., 1950, Geology of the Elkton area, Virginia: U.S. Geological 

Survey Professional Paper 230, 82 p.

 1970, Epilogue, in Fisher, G.W, Pettijohn, F.J., Reed, J.C., and

Weaver, K.N., eds., Studies of Appalachian geology Central and 

southern: New York, Wiley, 460 p.

King, P.B., and Beikman, H.M., 1974, Geologic map of the United States: 

U.S. Geological Survey special map, 3 sheets, scale 1:2,500,000.

Knight, A.L., 1976, Water availability, Jefferson County, Alabama: Geological Survey of Alabama Special Map 167.

Knopman, D.S., 1990, Factors related to water-yielding potential of

rocks in the Piedmont and Valley and Ridge Provinces of Pennsylvania: U.S. Geological Survey Water-Resources Investigations 

Report 90-4174, 52 p.

Kozar, M.D., Hobba, W.A., Jr., and Macy, J.A., 1991, Geohydrology, 

water availability, and water quality of Jefferson County, West 

Virginia, with emphasis on the carbonate area: U.S. Geological 

Survey Water-Resources Investigations Report 90-4118, 93 p.

Latta, B.F., 1956, Public and industrial ground-water supplies of the 

Roanoke-Salem district, Virginia: Virginia Division of Geology 

Bulletin 69, 53 p.

Lawton, D.E., Marsalis, WE., and others, 1976, Geologic map of Georgia: Georgia Geological Survey map, 1 sheet, scale 1:500,000.

Leonard, R.B., 1962, Ground-water geology along the northwest foot of 

the Blue Ridge between Arnold Valley and Elkton, Virginia: 

Blacksburg, Va., Virginia Polytechnic Institute and State University, unpublished Ph.D. dissertation, 211 p.

Lewis, J.V, and Kummel, H.B., 1912, Geologic map of New Jersey: New 

Jersey Department of Conservation and Economic Development 

Atlas Sheet 40,1 sheet, scale 1:250,000. Revised by Johnson, M.E., 

1950.

Lloyd, O.B., Jr., and Carswell, L.D., 1981, Groundwater resources of the 

Williamsport region, Lycoming County, Pennsylvania, Pennsylvania Geological Survey, 4th ser., Water Resource Report 51, 69 p.

Lloyd, O.B., Jr., and Lyke, W.L., 1995, Segment 10, Illinois, Indiana, Kentucky, Ohio, and Tennessee, Ground-water atlas of the United 

States: U.S. Geological Survey Hydrologic Atlas 730-K, 30 p.

Luther, E.T., 1985, Pine Mountain overthrust and adjacent areas, Tennessee, column 12, Valley and Ridge, Tennessee, column 13, 

Northern Unaka Mountains and adjacent Valley and Ridge, Tennessee, column 14, and Southern Unaka Mountains and adjacent 

Valley and Ridge, Tennessee, column 15, in Patchen, D.G., Avary, 

K.L., and Erwin, R.B., regional coords., Correlation of stratigraphic units of North America (COSUNA) project Southern 

Appalachian region: American Association of Petroleum Geologists, 1 sheet.

Lyttle, P.T., and Epstein, J.B., 1987, Geologic map of the Newark

1-degree by 2-degree quadrangle, New Jersey, Pennsylvania, and 

New York: U.S. Geological Survey Miscellaneous Investigations 

Series 1-1715, 2 sheets, scale 1:250,000.

MacLachlan, D.B., 1967, Structure and stratigraphy of the limestones 

and dolomites of Dauphin County, Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., General Geology Report G44,168 p.

Maclay, R.W, 1962, Geology and ground-water resources of the

Elizabethton-Johnson City area, Tennessee: U.S. Geological Survey Water-Supply Paper 1460-J, p. 386-436.

McCalley, Henry, 1897, Report on the valley regions of Alabama (Paleozoic strata) part 2 on the Coosa Valley region: Geological Survey 

of Alabama Special Report 9.

McColloch, J.S., 1986, Springs of West Virginia: West Virginia Geological and Economic Survey, v. V-6A, 493 p.

McLemore, W.H., 1971, The geology and geochemistry of the Mississippian System in northwest Georgia and southeast Tennessee: Athens, Ga., University of Georgia unpublished Ph.D. thesis.

 1985, Northwestern Valley and Ridge and Plateau, Georgia, column 9, and Southeastern Valley and Ridge, Georgia, column 10, 

in Patchen, D.G., Avary, K.L., and Erwin, R.B., regional coords., 

Correlation of stratigraphic units of North America (COSUNA) 

project Southern Appalachian region: American Association of 

Petroleum Geologists, 1 sheet.

McMaster, W.M., 1963, Geologic map of the Oak Ridge Reservation, 

Tennessee: Oak Ridge, Tennessee, U.S. Atomic Energy Commission, Oak Ridge National Laboratory, ORNL/TM-713, 23 p.

 1973, Water resources of Knox County, Tennessee, in Tennessee Division of Geology, Geology of Knox County, Tennessee, 

with field trips: Tennessee Division of Geology Bulletin 70, 

p. 102-104.

McMaster, W.M., and Hubbard, E.F., 1970, Water resources of the Great 

Smoky Mountains National Park, Tennessee and North Carolina: 

U.S. Geological Survey Hydrologic Investigations Atlas HA-420, 

2 sheets, scale 1:125,000.

Meisler, Harold, and Becher, A.E., 1971, Hydrogeology of the carbonate 

rocks of the Lancaster 15-minute quadrangle, Pennsylvania: 

Pennsylvania Geological Survey 4th ser., Water Resource 

Report 26,149 p.

Meng, A.A., III, Harsh, J.F., and Kull, T.K., 1985, Virginia ground-water 

resources in National water summary 1984 Hydrologic events, 

selected water-quality trends, and ground-water resources: U.S. 

Geological Survey Water-Supply Paper 2275, p. 427-432.

Meyer, Gerald, Wilmoth, B.M., and LeGrand, H.E., 1965, Sheet 10, 

Availability of ground water in the Appalachian region, in 

Schneider, W.J., and others, Water resources of the Appalachian 

region Pennsylvania to Alabama: U.S. Geological Survey Hydrologic Investigations Atlas HA-198,11 sheets, scale 1:2,500,000.

Milici, R.C., Harris, L.D., and Statler, A.T., 1979, An interpretation of 

seismic cross sections in the Valley and Ridge of eastern
HYDROGEOLOGIC TERRANES AND POTENTIAL YIELD OF WATER IN THE VALLEY AND RIDGE PROVINCE C29

Tennessee: Tennessee Division of Geology Oil and Gas Seismic 

Investigations Series 1.

Miller, E.V., and Hubbard, D.A., Jr., 1986, Selected slope categories and 

karst features map of Giles County, Virginia: Virginia Division of 

Mineral Resources Publication 70,1 sheet, scale 1:50,000.

Mills, H.H., and Delcourt, P.A., 1991, Quaternary geology of the Appalachian Highlands and Interior Low Plateaus, in Morrison, R.B., 

ed., Quaternary nonglacial geology; Conterminous U.S.: Boulder, 

Colo., Geological Society of America, The Geology of North 

America, v. K-2, p. 611-628.

Moffett, T.B., and Moser, P.W., 1978, Ground-water resources of the Birmingham and Cahaba Valleys of Jefferson County, Alabama: Geological Survey of Alabama Circular 103, 78 p.

Mooty, W.S., 1987, Geohydrology and susceptibility of major aquifers to 

surface contamination in Alabama; area 7: U.S. Geological Survey 

Water-Resources Investigations Report 87-4109, 28 p.

Newport, T.G., 1971, Ground-water resources of Montgomery County, 

Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water 

Resource Report 29, 83 p.

Nutter, L.J., 1973, Hydrogeology of the carbonate rocks, Frederick and 

Hagerstown Valleys, Maryland: Maryland Geological Survey 

Report of Investigations 19, 70 p.

Osborne, WE., Szabo, M.W, Copeland, C.W, Jr., and Neathery, T.L., 

1989, Geologic map of Alabama: Geological Survey of Alabama 

Special Map 221,1 sheet, scale 1:500,000.

Parizek, R.R., White, W.B., and Langmuir, Donald, 1971, Hydrogeology 

and geochemistry of folded and faulted carbonate rocks of the 

central Appalachian type and related land use problems field 

trip guidebook for Geological Society of America annual meeting, 

Washington, D.C., November 1971: State College, Pa., The Pennsylvania State University, 184 p.

Patchen, D.G., and Avary, K.L., 1985, Southeast Valley and Ridge, West 

Virginia, column 3, and northeast Valley and Ridge, West Virginia, column 10, in Patchen, D.G., Avary, K.L., and Erwin, R.B., 

regional coords., Correlation of stratigraphic units of North 

America (COSUNA) project Northern Appalachian region: 

American Association of Petroleum Geologists, 1 sheet.

Patchen, D.G., Avary, K.L., and Erwin, R.B., regional coords., 1985a, 

Correlation of stratigraphic units of North America (COSUNA) 

project Northern Appalachian region: American Association of 

Petroleum Geologists, 1 sheet.

 1985b, Correlation of stratigraphic units of North America 

(COSUNA) project Southern Appalachian region: American 

Association of Petroleum Geologists, 1 sheet.

Planert, Michael, and Pritchett, J.L., Jr., 1988, Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; 

area 4: U.S. Geological Survey Water-Resources Investigations 

Report 88-4133,31 p.

Price, PH., 1929, Pocahontas County: West Virginia Geological and Economic Survey County Geological Report Series, 531 p.

Price, PH., and Heck, E.T., 1939, Greenbrier County: West Virginia Geological and Economic Survey County Geological Report Series, 

846 p.

Rader, E.K., 1985a, Highland to Craig County, Virginia, column 4, Rockbridge and Botetourt Counties, Virginia, column 5, and northeast 

Valley and Ridge, Virginia, column 11, in Patchen, D.G., Avary, 

K.L., and Erwin, R.B., regional coords., Correlation of stratigraphic units of North America (COSUNA) project Northern 

Appalachian region: American Association of Petroleum Geologists, 1 sheet.

 1985b, Lee County, Virginia, column 20, Scott and Russell Counties, Virginia, column 22, Wythe and Pulaski Counties, Virginia, 

column 25, in Patchen, D.G., Avary, K.L., and Erwin, R.B., regional 

coords., Correlation of stratigraphic units of North America

(COSUNA) project Southern Appalachian region: American 

Association of Petroleum Geologists, 1 sheet.

Reger, D.B., 1924, Mineral and Grant Counties: West Virginia Geological and Economic Survey County Geological Report Series, 866 p.

 1926, Mercer, Monroe, and Summers Counties: West Virginia 

Geological and Economic Survey County Geological Report 

Series, 963 p.

Robinson, W.H., Ivey, J.B., and Billingsley, G.A., 1953, Water supply of 

the Birmingham area, Alabama: U.S. Geological Survey 

Circular 254.

Rodgers, John, comp., 1953, Geologic map of East Tennessee with

explanatory text: Tennessee Division of Geology Bulletin 58, pt. 2, 

168 p.

Root, S.I., 1968, Geology and mineral resources of southeastern Franklin County, Pennsylvania: Pennsylvania Geological Survey 

Atlas 119cd, 118 p.

Rutledge, A.T., and Mesko, TO., 1996, Estimated hydrologic characteristics of shallow aquifer systems in the Valley and Ridge, the Blue 

Ridge, and the Piedmont Physiographic Provinces based on analysis of streamflow recession and base flow: U.S. Geological Survey Professional Paper 1422-B, 58 p.

Saad, D.A., and Hippe, D.J., 1990, Large springs in the Valley and Ridge 

Physiographic Province of Pennsylvania: U.S. Geological Survey 

Open-File Report 90-164,17 p.

Safford, T.H., Jr., 1966, Ground water in Marshall County, Alabama A 

reconnaissance: Geological Survey of Alabama Bulletin 85, 66 p.

SAS Institute, Inc., 1985, SAS user's guide Statistics (5th ed.): Carey, 

N.C., SAS Institute, Inc., 956 p.

Schneider, W.J., and others, 1965, Water resources of the Appalachian 

region, Pennsylvania to Alabama: U.S. Geological Survey Hydrologic Investigations Atlas HA-198,11 sheets, scale 1:2,500,000.

Schultz, A.P., Stanley, C.B., Gathright, T.M., II, Rader, E.K., Bartholomew, M.J., Lewis, S.E., and Evans, N.H., 1986, Geologic map of 

Giles County, Virginia: Virginia Division of Mineral Resources 

Publication 69,1 sheet, scale 1:50,000.

Scott, J.C., Cobb, R.H., and Castleberry, R.D., 1987, Geohydrology and 

susceptibility of major aquifers to surface contamination in Alabama; area 8: U.S. Geological Survey Water-Resources Investigations Report 86-4360, 65 p.

Scott, J.C., Harris, W.F., and Cobb, R.H., 1987, Geohydrology and susceptibility of Coldwater Spring and Jacksonville Fault areas to 

contamination, Calhoun County, Alabama: U.S. Geological Survey Water-Resources Investigations Report 87-4031, 29 p.

Seaber, PR., and Hollyday, E.F., 1965, An appraisal of the ground-water 

resources of the lower Susquehanna River basin: U.S. Geological 

Survey open-file report, 75 p.

Sevon, W.D., 1989, Surficial materials of Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., Map 64,1 sheet, scale 1:2,000,000.

Shamburger, J.M., and Harkins, J.R., 1980, Water availability, Shelby 

County, Alabama: Geological Survey of Alabama Special 

Map 140.

Sherwood, W.C., 1964, Structure of the Jacksonburg Formation in

Northampton and Lehigh Counties, Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., General Geology Report G45, 64 p.

Siddiqui, S.H., and Parizek, R.R., 1971, Hydrogeologic factors influencing well yields in folded and faulted carbonate rocks in central 

Pennsylvania: Water Resources Research, v. 7, no. 5, p. 1295-1312.

Simpson, T.A., 1965, Geologic and hydrologic studies in the Birmingham red-iron-ore district, Alabama: U.S. Geological Survey Professional Paper 473, 47 p.

Sitterly, P.D., and Wilson, R.L., comps., 1978, Environmental geology of 

Hamilton County, Tennessee: Tennessee Division of Geology Bulletin 79, pt. 2,1 sheet, scale 1:48,000.
C30 REGIONAL AQUIFER-SYSTEM ANALYSIS APPALACHIAN VALLEY AND PIEDMONT

Slaughter, T.H., and Darling, J.M., 1962, The water resources of Allegany and Washington Counties: Maryland Department of Geology, Mines and Water Resources Bulletin 24, 408 p.

Smith, E.A., 1907, The underground water resources of Alabama: Geological Survey of Alabama Monograph 6,388 p.

Sun, P-C.R, Criner, J.H., and Poole, J.L., 1963, Large springs of East Tennessee: U.S. Geological Survey Water-Supply Paper 1755, 52 p.

Sun, R.J., 1986, Regional aquifer-system analysis program of the U.S. 

Geological Survey Summary of projects, 1978-1984: U.S. Geological Survey Circular 1002,264 p.

Swain, L.A., Hollyday, E.F., Daniel, C.C., III, and Zapecza, O.S., 1991, 

Plan of study for the regional aquifer-system analysis of the 

Appalachian Valley and Ridge, Piedmont, and Blue Ridge Physiographic Provinces of the Eastern and Southeastern United States, 

with a description of study-area geology and hydrogeology: U.S. 

Geological Survey Water-Resources Investigations Report 

91-4066, 44 p.

Taylor, P.M., and Rosier, M.T., 1986, Ground-water data for West Virginia, 1974-84: U.S. Geological Survey Open-File Report 86-320, 

66 p.

Taylor, L.E., Werkheiser, W.H., DuPont, N.S., and Kriz, M.L, 1982,

Groundwater resources of the Juniata River basin, Pennsylvania: 

Pennsylvania Geological Survey, 4th ser., Water Resource 

Report 54,131 p.

Taylor, L.E., Werkheiser, W.H., and Kriz, M.L., 1983, Groundwater

resources of the West Branch Susquehanna River basin, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water Resource 

Report 56,143 p.

Tilton, J.L., Prouty, W.F., and Price, PH., 1927, Pendleton County: West 

Virginia Geological and Economic Survey County Geological 

Report Series, 384 p.

Trainer, F.W, and Watkins, F.A., 1975, Geohydrologic reconnaissance of 

the upper Potomac River basin: U.S. Geological Survey WaterSupply Paper 2035, 68 p.

Tucci, Patrick, 1992, Hydrology of Melton Valley at Oak Ridge National 

Laboratory, Tennessee: U.S. Geological Survey Water-Resources 

Investigations Report 92-4131, 76 p.

Warman, J.C., and Causey, L.V, 1962a, Geologic map of Calhoun

County, Alabama: Geological Survey of Alabama Special Map 17.

 1962b, Geology and ground-water resources of Calhoun County, 

Alabama: Geological Survey of Alabama County Report 7, 77 p.

Warman, J.C., Causey, L.V, Burks, J.H., and others, 1960, Geology and 

ground-water resources of Calhoun County, Alabama Interim 

report: Geological Survey of Alabama Information Series 17, 67 p.

Webster, D.A., and Bradley, M.W, 1988, Hydrology of the Melton Valley 

radioactive-waste burial grounds at Oak Ridge National Laboratory, Tennessee: U.S. Geological Survey Open-File Report 87-686, 

115 p.

Webster, D.A., and Carmichael, J.K., 1993, Ground-water hydrology of 

the lower Wolftever Creek basin, with emphasis on the Carson 

Spring area, Hamilton County, Tennessee: U.S. Geological Survey 

Water-Resources Investigations Report 91-4190,47 p.

Wenzel, L.K., 1942, Methods for determining permeability of waterbearing materials: U.S. Geological Survey Water-Supply 

Paper 887,192 p.

White, W.B., 1988, Geomorphology and hydrology of karst terrains: 

New York, Oxford University Press, 464 p.

Williams, J.H., and Eckhardt, D.A., 1987, Groundwater resources of the 

Berwick-Bloomsburg-Danville area, East-Central Pennsylvania: 

Pennsylvania Geological Survey, 4th ser., Water Resource 

Report 61, 76 p.

Wood, C.R., 1980, Summary groundwater resources of Centre County, 

Pennsylvania: Pennsylvania Geological Survey, 4th ser., Water 

Resource Report 48, 60 p.

Wood, C.R., Flippo, H.N., Jr., Lescinsky, J.B., and Barker, J.L., 1972, 

Water resources of Lehigh County, Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., Water Resource Report 31, 263 p.

Wood, C.R., and MacLachlan, D.B., 1978, Geology and groundwater 

resources of northern Berks County, Pennsylvania: Pennsylvania 

Geological Survey, 4th ser., Water Resource Report 44, 91 p.

Woodward, N.B., ed., 1985, Valley and Ridge thrust belt Balanced 

structural sections, Pennsylvania to Alabama: Knoxville, Tenn., 

University of Tennessee Department of Geological Sciences Studies in Geology 12, 64 p.

Wright, W.G., 1990, Ground-water hydrology and quality in the Valley 

and Ridge and Blue Ridge Physiographic Provinces of Clarke 

County, Virginia: U.S. Geological Survey Water-Resources Investigations Report 90-4134, 61 p.

Zurawski, Ann, 1978, Summary appraisals of the Nation's groundwater resources Tennessee Region: U.S. Geological Survey Professional Paper 813-L, 35 p.

 ft U.S. GOVERNMENT PRINTING OFFICE: 1997-547-552