Cedar Breaks National Monument 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2006/006 

National Park Service 

U.S. Department of the Interior 

Natural Resource Program Center 

Cedar Breaks National Monument 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2006/006 

Geologic Resources Division 

Natural Resource Program Center 

P.O. Box 25287 

Denver, Colorado 80225 

March 2006 

U.S. Department of the Interior 

Washington, D.C.
The Natural Resource Publication series addresses natural resource topics that are of interest 

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Printed copies of reports in these series may be produced in a limited quantity and they are 

only available as long as the supply lasts. This report is also available from the Geologic 

Resource Evaluation Program website (http://www2.nature.nps.gov/geology/inventory/

gre_publications) on the internet, or by sending a request to the address on the back cover. 

Please cite this publication as: 

Thornberry-Ehrlich, T. 2006. Cedar Breaks National Monument Geologic Resource 

Evaluation Report. Natural Resource Report NPS/NRPC/GRD/NRR—2006/006. National 

Park Service, Denver, Colorado. 

NPS D-215, March 2006 
 CEBR Geologic Resource Evaluation Report iii 

Table of Contents 

List of Figures .............................................................................................................. iv

Executive Summary ...................................................................................................... 1

Introduction ................................................................................................................... 3

Purpose of the Geologic Resource Evaluation Program ............................................................................................3

Geologic Setting .........................................................................................................................................................3

Geologic Issues............................................................................................................. 8

Slope Processes.........................................................................................................................................................8

Seismicity and Mining.................................................................................................................................................8

Karst and fracturing within the Claron Formation........................................................................................................9

Water Issues...............................................................................................................................................................9

Ecosystems and Cultural Resources........................................................................................................................10

Hoodoo Formation and Present Condition ...............................................................................................................10

Paleontologic Potential .............................................................................................................................................10

Faulting and Deformation Processes........................................................................................................................10

Mining Issues............................................................................................................................................................11

Marysvale Volcanic Field..........................................................................................................................................12

Wind Erosion and Deposition ...................................................................................................................................12

General Geology ......................................................................................................................................................12

Geologic Features and Processes............................................................................. 13

Markagunt Megabreccia ...........................................................................................................................................13

Structural Features...................................................................................................................................................13

Erosion of the landscape ..........................................................................................................................................13

Hoodoo Formation....................................................................................................................................................14

Other Features .........................................................................................................................................................14

Map Unit Properties .................................................................................................... 15 

Map Unit Properties Table........................................................................................................................................16

Geologic History.......................................................................................................... 19

References................................................................................................................... 28

Appendix A: Geologic Map Graphic .......................................................................... 31

Appendix B: Scoping Summary................................................................................. 33 

Attachment 1: Geologic Resource Evaluation Products CD
iv NPS Geologic Resources Division 

List of Figures 

Figure 1: Location of Cedar Breaks National Monument................................................................................................5

Figure 2: The Colorado Plateau .....................................................................................................................................6

Figure 3: Geologic cross-section illustrating the “Grand Staircase”................................................................................7

Figure 4: West to east geologic cross section through the central part of Cedar Breaks National Monument ...............7

Figure 5: Geologic time scale.......................................................................................................................................22

Figure 6: Location of the Cretaceous Period, Western Interior Seaway.......................................................................23

Figure 7: Location of Cedar Breaks National Monument on a tectonic map showing Laramide-age structures...........24

Figure 8: Early post-Laramide map..............................................................................................................................25

Figure 9: Tertiary (primarily Miocene) volcanic centers in southern Utah and Nevada ................................................26

Figure 10: Generalized graphic overview of geologic evolution of Utah.......................................................................27
 CEBR Geologic Resource Evaluation Report 1 

Executive Summary 

This report has been developed to accompany the digital geologic map produced by Geologic 

Resource Evaluation staff for Cedar Breaks National Monument. It contains information 

relevant to resource management and scientific research. 

Cedar Breaks National Monument provides visitors the 

rare opportunity of standing in one physiographic 

province while viewing a panorama of an entirely 

different physiographic province. Visitors standing on 

the nearly flat- lying strata of the Colorado Plateau can 

look to the west at the stark landscape of the Basin and 

Range province. 

This splendid view is eclipsed only by the multicolored 

cliffs, spires, pinnacles, and other geologic features 

carved by erosion and weathering into the natural 

amphitheaters just below the rim, or “break” in the 

gently east- dipping, pine- covered surface of the plateau. 

The geologic processes of weathering and erosion are 

vividly captured in stone and yet, are not static. 

Relentlessly working towards a dynamic equilibrium, 

these processes shape and reshape the landscape treating 

visitors to a changing and vibrant viewscape. 

The Markagunt Plateau is a small part of the High 

Plateaus region of the Colorado Plateau Physiographic 

province. Cedar Breaks forms the western escarpment of 

the Markagunt Plateau delineating the boundary 

between the Colorado Plateau and the Basin and Range 

Physiographic Provinces. The unparalleled geologic 

variety of the region attracted over 514,000 visitors in 

2004. Visitors are drawn by the myriad of rock shapes 

including columns, spires, hoodoos, windows, pedestals, 

bridges, alcoves, and canyons, and other spectacular 

geological features carved into the red, orange, and white 

fluvial and lacustrine strata of the Claron Formation. 

Although visitors appreciate the geologic wonders of 

Cedar Breaks their very numbers place increasing 

demands on available resources. 

Understanding the geology of Cedar Breaks enhances 

one’s understanding of the unique relationship between 

geology and the environment. Geology provides the 

foundation of the entire ecosystem. In Cedar Breaks 

National Monument surface exposures consist primarily 

of Cretaceous, Tertiary, and Quaternary age rocks. Rock 

layers are exposed by erosion of the Markagunt Plateau, 

revealing clues about the varied environments 

responsible for creating the present landscape. Knowing 

the geology in detail is fundamental to determining the 

history of Cedar Breaks National Monument and to 

managing and preserving geologic features today. 

Geologic processes initiate complex responses that give 

rise to rock formations, surface and subsurface fluid 

movement, soils, and canyons. Preservation of the 

canyons, spires, alcoves, and hoodoos of Cedar Breaks 

National Monument is absolutely necessary for the 

continued inspiration of wonder in park visitors. 

Emphasis of geologic resources both in natural resource 

management and in educational program is certain to 

enhance the visitor’s experience. 

Cedar Breaks National Monument, which mirrors the 

multi- colored landscape of Bryce Canyon National Park, 

its better known neighbor 40 miles to the east, hosts 

some of the most spectacular desert erosional features on 

earth. The interplay of geology, water, tectonic forces, 

and climate created this architectural elegance on the 

landscape at Cedar Breaks. Some of the principal 

geologic issues and concerns for the monument pertain 

to protecting these features. Humans have modified the 

landscape surrounding Cedar Breaks and consequently 

have altered the natural geologic processes. These 

processes are dynamic and capable of noticeably 

changing the landscape within a human life span (less 

than a century). The following features, issues, and 

processes have been identified as having the most 

geological importance and the highest level of 

management significance to the monument: 

• Slope failures and slope processes. Arid, desert 

environments are especially susceptible to slumping 

and landslide problems due to the lack of stabilizing 

plant growth and the relatively frequent occurrence of 

intense seasonal rainstorms. Construction of roads and 

trails also impacts the stability of a slope. Mudstonerich units such as the Brian Head Formation are 

typically found in outcrop as slopes. These slopes are 

prone to fail when saturated. In addition the more 

resistant units in the monument are exposed as cliffs 

and precipitous slopes. Rockfall and slope failure is a 

potential hazard almost everywhere along the roads 

and trails of Cedar Breaks National Monument. 

• Seismic and mining activity. Cedar Breaks was created 

to preserve and protect some of the most spectacular 

erosional spires and other geologic features in the 

world, yet this area is still seismically active. In addition 

to natural seismicity, vibrations from blasting at nearby 

mines are also putting these features at risk. 

• Fracturing and karst development in the Claron 

Formation. The Tertiary age Claron Formation forms 

the spectacular hoodoos and other erosional features 

that delight visitors. However, the fractures and 

sinkholes inherent in the formation also pose serious 

threats to overlooks and other visitor facilities. Caves 

may also play a cultural resource role at the 

monument. 

• Water Issues. The southern Utah mountains receive on 

average about 8- 10 inches of precipitation each year 

with higher altitudes receiving more. This sparse 

rainfall defines the arid climate that makes water such 
2 NPS Geologic Resources Division 

an important resource regionally. Water for Cedar 

Breaks National Monument comes primarily from 

wells drawing water from aquifers in the Claron 

Formation and Straight Cliffs Sandstone. Productive 

aquifers must be deep enough to be relatively 

impervious to drought conditions and be contained in 

fractured rock that provides groundwater conduits to 

the well. The hydrogeologic system at the monument is 

not well understood and warrants further study. 

Other geologic issues such as the paleontological 

potential of the area, wind erosion, hoodoo formation 

and preservation, faulting and deformation processes, 

and the story of the Marysvale Volcanic Field, were also 

identified as important management issues for Cedar 

Breaks National Monument. 

It is the interaction of the variety of rock types with the 

topographic landscape created by uplift and erosion that 

must be understood to assess potential hazards and best 

protect the visitors to the park. The Map Unit Properties 

section of this report details the different units and 

potential resources, concerns and issues associated with 

each. 
 CEBR Geologic Resource Evaluation Report 3 

Introduction 

The following section briefly describes the regional geologic setting and the National 

Park Service Geologic Resource Evaluation Program. 

Purpose of the Geologic Resource Evaluation Program 

Geologic features and processes serve as the foundation 

of park ecosystems and an understanding of geologic 

resources yields important information for use in park 

decision making. The National Park Service Natural 

Resource Challenge, an action plan to advance the 

management and protection of park resources, has 

focused efforts to inventory the natural resources of 

parks. Ultimately, the inventory and monitoring of 

natural resources will become integral parts of park 

planning, operations and maintenance, visitor 

protection, and interpretation. The geologic component 

is carried out by the Geologic Resource Evaluation 

(GRE) Program administered by the NPS Geologic 

Resources Division. The goal of the GRE Program is to 

provide each of the identified 270 “Natural Area” parks 

with a digital geologic map, a geologic resource 

evaluation report, and a geologic bibliography. Each 

product is a tool to support the stewardship of park 

resources and is designed to be user friendly to nongeoscientists. 

GRE teams hold scoping meetings at parks to review 

available data on the geology of a particular park and to 

discuss specific geologic issues affecting the park. Park 

staff are afforded the opportunity to meet with experts 

on the geology of their park during these meetings. 

Scoping meetings are usually held for individual parks 

although some meetings address an entire Vital Signs 

Monitoring Network. 

Bedrock and surficial geologic maps and information 

provide the foundation for studies of groundwater, 

geomorphology, soils, and environmental hazards. 

Geologic maps describe the underlying physical habitat 

of many natural systems and are an integral component 

of the physical inventories stipulated by the National 

Park Service (NPS) in its Natural Resources Inventory 

and Monitoring Guideline (NPS- 75) and the 1997 NPS 

Strategic Plan. The NPS GRE is a cooperative 

implementation of a systematic, comprehensive 

inventory of the geologic resources in National Park 

System units by the Geologic Resources Division, the 

Inventory, Monitoring, and Evaluation Office of the 

Natural Resource Program Center, the U.S. Geological 

Survey, and state geological surveys. 

For additional information regarding the content of this 

report, please refer to the Geologic Resources Division of 

the National Park Service, located in Denver, Colorado 

with up- to- date contact information at the following 

website: http://www2.nature.nps.gov/geology/inventory/ 

Geologic Setting 

Traveling across the High Plateau country of the 

Colorado Plateau, early explorers and settlers often came 

across cliff like edges that would “break” the relatively 

flat plateaus, resulting in time consuming, and often 

extremely dangerous detours. The juniper, known to the 

early settlers as “cedar,” grew thick upon the plateaus; 

hence the name “Cedar Breaks.” 

Located in south- central Utah, Cedar Breaks National 

Monument encompasses about 6,155 acres of high desert 

landscape. The elevation in the park averages about 3,353 

m (11,000 ft). The monument contains an erosional 

landscape modified by glacial and periglacial processes. 

The erosional amphitheatre of Cedar Breaks lies on the 

western rim of the Markagunt Plateau at 3,170 m 

(10,400 ft) elevation (figure 1). The Markagunt Plateau 

contains the highest elevations in southwestern Utah. A 

few miles north of Cedar Breaks, the basalt- capped 

Brianhead Peak reaches 3,449 m (11,315 ft) in elevation. 

In the 1870s, Major John Wesley Powell began regional 

geological studies of the four corners area. One of the 

premier geologists with the Powell Survey, Clarence 

Dutton, recognized the Grand Staircase, a stair- step 

arrangement of cliff- forming rock layers that became 

progressively younger northward from the Grand 

Canyon (figure 3). The Tertiary- age Claron Formation 

that forms the majority of the rocks exposed at Cedar 

Breaks is one of the younger formations exposed in this 

Grand Staircase. 

Over millions of years, sedimentary rocks of the Claron 

Formation and younger Tertiary rocks have been 

uplifted, eroded, and carved into a deep canyon that 

spans three miles and is over 2,000 feet deep. Cedar 

Breaks National Monument was set aside to preserve and 

protect an incredible collection of hoodoos. These 

fascinating geomorphological shapes include spires, fins, 

pinnacles, canyons, and mazes. The erosion of colorful 

sandstones, mudstones, and limestones left behind these 

fantastic remnants on the landscape. Erosional processes 

are also responsible for some of the management 

concerns at Cedar Breaks National Monument. 

Cedar Breaks National Monument is located at the 

western margin of the Colorado Plateau, in the High 

Plateau region. The Colorado Plateau is a broad area of 

relative structural stability between the Rocky Mountains 

and the Basin and Range Physiographic Provinces. 

The Colorado Plateau remains somewhat of a tectonic 

mystery and has undergone relatively little geologic 

deformation compared to the surrounding regions 

(Graham et al. 2002). It is roughly circular in shape, and 
4 NPS Geologic Resources Division 

extends about 483 km (300 miles) in an east- west 

direction and 644 km (400 miles) in the north- south 

direction. It ranges in altitude from about 762 m (2,500 ft) 

along the Colorado River, to about 3,962 m (13,000 ft) on 

some of the isolated peaks. The principal tectonic 

features of the plateau are basins, uplifts, monoclinal 

flexures, domes of igneous intrusion, platforms, slopes 

and broad saddles, and fold and fault belts (Kelley and 

Clinton 1960) (figure 2). Perhaps more than any other 

structural feature, the Colorado Plateau is characterized 

by monoclines, which, if lined up from end to end, would 

comprise an aggregate length of nearly 4,023 km (2,500 

miles) (Kelley 1955). The term monocline, as defined by 

Powell in 1873, describes a bend or local steepening in 

otherwise gently inclined beds. 

Surrounding Cedar Breaks are various uplifts, 

monoclines, and mountains. To the southwest, the 

Kaibab (monoclinal) Uplift dominates the area. The 

Circle Cliffs, Monument Uplift, and San Rafael Swell are 

to the northeast as are the Henry Mountains and the 

Miner’s Mountain monocline. The Marysvale Volcanic 

Field borders the region on the north side. The 

Markagunt Plateau lies west of the Paunsaugunt Plateau 

that dominates Bryce Canyon National Park. It is at the 

edge of the High Plateaus province. To the east and 

northeast are the Table Cliff Plateau and the Kaiparowits 

Plateau, respectively. 
 CEBR Geologic Resource Evaluation Report 5 

Figure 1. Location of Cedar Breaks National Monument relative to Zion National Park and Bryce Canyon National Park. Modified from 

Gregory (1950). 
6 NPS Geologic Resources Division 

Figure 2. The Colorado Plateau, showing some of the significant uplifts, basins, faults, volcanic centers, and rivers. High areas are 

shown in gray: AM, Abajo Mts.; AP, Aquarius Plateau; BC, Book Cliffs; CCU, Circle Cliffs Uplift; DU, Defiance Uplift; KU, Kaibab Uplift; 

LSM, La Sal Mts.; MU, Monument Upwarp; RC, Roan Cliffs; SRS, San Rafael Swell; UU, Uncompahgre Uplift. Basins: PB, Paradox 

Basin; UB, Uinta Basin. Leading edge of Sevier Thrust Belt is shown as sawtooth with teeth on upper, overriding thrust plate. Modified 

from Kiver and Harris, 1999. 
 CEBR Geologic Resource Evaluation Report 7 

Figure 3. Geologic cross-section illustrating the “Grand Staircase” from the Grand Canyon to Bryce Canyon/Cedar Breaks. Rocks 

exposed as Cedar Breaks are colored yellow. “Ma”: Millions of years ago; “Ba”: billions of years ago. Modified from the geologic cross 

section published by the Zion Natural History Association, 1975. 

Figure 4. West to east geologic cross section through the central part of Cedar Breaks National Monument. Modified from Hatfield and 

others (2000). 
8 NPS Geologic Resources Division 

Geologic Issues 

A Geologic Resource Evaluation scoping session was held for Cedar Breaks National 

Monument July 15- 16, 1999, to discuss geologic resources, to address the status of geologic 

mapping, and to assess resource management issues and needs. The following section 

synthesizes the scoping results, in particular, those issues that may require attention 

from resource managers. 

Slope Processes 

Intense erosion of the relatively soft Tertiary Claron 

Formation is responsible for the vast array of hoodoos 

and canyons present at Cedar Breaks National 

Monument. However, erosional processes also are the 

cause of the most important geological resource 

management issues in the monument: landslides and 

rockfalls. Present and future construction and 

maintenance plans need to address fracturing and 

landslide (mass wasting) potential in the various 

formations listed as high risk in the Map Unit Properties 

section of this report. 

Canyons and amphitheatres in Cedar Breaks have nearly 

vertical walls. This renders them highly dangerous 

because of the likelihood of rock falls, landslides, slumps, 

and slope creep. This issue is a major concern in the 

weaker rock units including the red member of the 

Claron Formation. Stronger rock units such as the White 

member of the Claron Formation and the Straight Cliffs 

Sandstone are highly fractured increasing the probability 

of rockfalls. 

Slumps and other forms of slope failure are common for 

units that do not form cliffs. Unconsolidated alluvium, 

for example, is especially vulnerable to failure when 

exposed on a slope. Precipitation, which often produces 

flash flooding at Cedar Breaks, loosens rock and soil on 

slopes lacking stabilizing plant and tree roots. Rock and 

soil, when saturated with water, will slip down slope 

causing a slump, mudslide or debris flow. Landslide 

deposits have been mapped in Quaternary sediments, in 

the Markagunt Megabreccia, and in the Brian Head 

Formation. Quaternary landslide deposits (Ql) are 

identified on the geologic map. 

New construction or routine maintenance work could 

trigger slope failure. If a road displaces the toe of a 

previous landslide, it could reactivate that landslide. 

Therefore, constructing roads, buildings, campgrounds, 

infrastructure, pipes, and water wells on landslide 

deposits and/or within the path of potential landslides 

should be avoided. Trails in the monument lead visitors 

through spectacular desert scenery; however, many of 

these trails are at high risk for rockfalls and landslides. 

Inventory, Monitoring, and/or Research Needs for Slope 

Processes 

• Perform a comprehensive study of the erosion 

processes active at Cedar Breaks National Monument, 

taking into account the different rock formations, 

slope aspects, location, and likelihood of instability. 

• Create a rockfall susceptibility map using rock unit 

versus slope aspect in a GIS; use the map to plan future 

developments and aid current resource management 

of trails, buildings, and recreational use areas. 

• Inventory and monitor debris flow potential near 

picnic areas; relate to slope and loose rock deposits. 

Possible methods for this type of monitoring range 

from simple stakes that can be located and monitored 

using periodic GPS measurements to high- tech 

continual laser readings. 

• Inventory areas susceptible to flash floods and relate 

them to climate and flow patterns. 

• Perform trail stability studies and determine which 

trails are most at risk and in need of further 

stabilization. 

• Monitor areas planned for development for growth of 

fractures and for potential mass wasting. 

• Study old landslides in detail to determine the amount 

of material moved, the cause of movement, the 

porosity and permeability of the landslide material, 

and the degree of saturation prior to movement. Also, 

inventory and document the slope angle and the 

impacts of mass movements. 

Seismicity and Mining 

The Basin and Range and Colorado Plateau are still 

seismically active. Minor earthquakes occur in Nevada 

and Utah almost daily, most too small to be detected 

without a seismometer. The Wasatch Front, north of 

Cedar Breaks, near Salt Lake City, is due for a major 

earthquake. No historical earthquakes associated with 

surface rupture have occurred along the Wasatch fault 

zone during at least the past 133 years. However, the 

recurrence interval, or time between major seismic 

events, for the entire Wasatch fault zone may be 50 to 

430 years (Swan et al. 1980). The Hurricane fault zone 

underlies the western scarp of the Markagunt Plateau. 

This fault zones is one of the major displacement areas 

within the Basin and Range, accommodating at least 

3,050 m (10,000 ft) of movement in the Cedar City area. 

This fault and other local normal faults within and to the 

west of Cedar Breaks National Monument are still 

considered seismically active. Washington, Utah, near St. 

George, experienced a magnitude 5.9 earthquake in 1992 

(Hatfield et al. 2000). Most of the faults within the 

monument are north to northeast trending and smallscale with less than 30 m (100 ft) of displacement. 
 CEBR Geologic Resource Evaluation Report 9 

Several mines that use blasting to extract ore, coal, and 

other resources are located near Cedar Breaks National 

Monument. Blasting creates seismic waves that 

propagate through the earth, resulting in surface 

vibration. 

The delicate hoodoos of Cedar Breaks National 

Monument are largely the reason the area was set aside 

for preservation and protection. Severe ground shaking 

from either natural or man- made sources, has a great 

impact on the geomorphology of Cedar Breaks and is 

considered a significant resource management issue. 

Inventory, Monitoring, and/or Research Needs for Seismicity 

and Mining 

• Perform a comprehensive study of the faulting and 

seismic processes active at Cedar Breaks National 

Monument, taking into account rock formations, slope 

aspects, location and likelihood of instability. 

• Monitor slopes along trails particularly in areas prone 

to fail in the event of seismic activity in the area. 

• Develop a visitor access plan to avoid areas beneath 

the rim of the canyons to avoid rockfalls. 

• Monitor seismic activity in the Cedar Breaks area by 

cooperating with local agencies including the USGS 

and Utah Geological Survey. 

• Determine the effects of nearby mining, including 

blasting, on the delicate features at Cedar Breaks. How 

does this relate to natural seismicity in the area? 

• Perform a comprehensive study of the seismicity of 

active faults in close proximity to Cedar Breaks area 

including the mapping of small- scale faults and shear 

fractures. 

Karst and fracturing within the Claron Formation 

Fracturing in the Claron Formation is a geological 

process that has the potential to disrupt the stability and 

safety of visitor overlooks. Increased erosion from 

fracture failure and landsliding (mass wasting) also pose 

potential problems for the resource manager. The Brian 

Head Formation, Markagunt Megabreccia, and 

unconsolidated Quaternary sediments have the highest 

risk of failure by mass wasting. 

Sinkholes, seeps, springs, and other karst- related 

features have also developed in the Tertiary Claron 

Formation. Sinkhole development may impact new and 

existing construction. Caves associated with springs may 

yield cultural artifacts, including dwellings, tools, and 

petroglyphs. 

Inventory, Monitoring, and/or Research Needs for Karst and 

Fracturing within the Claron Formation 

• Perform a comprehensive inventory of the fractures in 

the Claron Formation and develop a plan to monitor 

any change in the fractures including photodocumentation and measurements of fractures. 

• Inventory sinkholes and areas that are likely to develop 

sinkholes. 

• Inventory caves in the monument. 

• Perform detailed studies of the Claron and Brian Head 

Formations along with cataloging the geological 

features of Cedar Breaks National Monument using a 

Global Positioning System and GIS. These studies 

would also help in monitoring rates of erosion and 

weathering. 

Water Issues 

Water is principally responsible for the formation of the 

various rock shapes at Cedar Breaks, and continues to 

play a critical role in sculpting the landscape. Rain at 

Cedar Breaks often occurs as locally torrential showers. 

The intensity of rain in a country almost barren of soil 

and vegetation results in severe erosion (Gregory and 

Moore 1931). Intense rain events falling on unprotected 

soil knocks apart individual soil particles and washes 

unconsolidated sediment into the canyons. 

Rainwater combines with carbon dioxide in the 

atmosphere to form carbonic acid (H2CO3). Although a 

weak acid, over time carbonic acid effectively dissolves 

limestone in rock layers and in intergranular cement. 

Lindquist (1980) discovered that the freeze and thaw 

action of water on the rocks at nearby Bryce Canyon 

National Park was perhaps the most effective weathering 

process. 

Numerous small springs forming where the ground 

surface intersects an aquifer or groundwater conduit, are 

especially common along very steep slopes. The two 

types of springs in the Cedar Breaks area are alluvial and 

bedrock springs. Alluvial springs are formed by water 

pockets near the surface in unconsolidated sediments. 

Much deeper are bedrock springs which originate from 

flow along fractures and bedding planes within lithified 

rock. 

Water, though integral, is scarce on the Markagunt 

Plateau, as it is for southern Utah in general. Much of the 

water used at the park comes from wells, penetrating the 

surface to reach aquifers in the Claron Formation, 

Wahweap and Straight Cliffs Sandstones. Aquifers must 

be deep enough to be relatively impervious to drought 

and occur in fractured rock to provide groundwater 

conduits to the well. 

Inventory, Monitoring, and/or Research Needs for Water 

Issues 

• Determine the nature of the watershed of the 

monument by compiling baseline watershed data, and 

surface and subsurface hydrogeologic data, including 

discharge rates of surface water. 

• Monitor water quality on a multiple sample location 

basis within the park; drinking water sources are 

especially important. 

• Perform hydrogeologic studies of the groundwater and 

surface water systems to better define groundwater 

flow, and the association of groundwater with karst 

and cave development. 

• Study groundwater flow patterns. A drinking water 

supply and low water use alternatives for waste 

disposal are two significant issues for Cedar Breaks; 
10 NPS Geologic Resources Division 

knowledge of groundwater flow patterns and 

alternative waste technologies would be beneficial to 

the resource manager. 

• Research the effects of a forest canopy on surface 

water availability. How does it impact the water supply 

and the ecosystem as a whole? 

• Install additional wells for testing and drinking water. 

• Study the impacts of nearby mining operations on the 

hydrology of the area (see above mining issues 

discussion). 

• Identify and study potential sources of groundwater 

for quality. 

• Install transducers and data loggers in wells. 

• Investigate additional methods to characterize 

groundwater recharge areas and flow directions. 

• Study groundwater recharge mechanisms and shallow 

subsurface flow in carbonate terrains in the southern 

Utah. 

• Conduct a study of aquifer permeability and of the 

quantity of water present in Cedar Breaks National 

Monument. 

Ecosystems and Cultural Resources 

Inventory, Monitoring, and/or Research Needs for 

Ecosystems and Cultural Resources 

• Study the fire history of bogs for the last 20,000 years. 

Lowder Creek can be traced back 17,000 years, Red 

Valley 11,000 years, and Alpine Pond 3,000 years. 

• Monitor and inventory human impacts in the park, 

including cultural resources. 

• Research chert distribution around the monument. 

The distribution of chert has numerous cultural 

implications. 

• Develop a better understanding of the relationship 

between clustered vegetation and bedrock strata. 

• Determine the relationship between geology and 

archeology by studying dune and mud deposits on the 

rim. 

Hoodoo Formation and Present Condition 

Preserving and maintaining hoodoos and other 

landforms in their natural environment is a key resource 

management issue for Cedar Breaks National 

Monument. The relationship between rock units and 

erosional processes is a dynamic one. Changes in climate, 

especially precipitation, have a profound effect on the 

entire system. Determining the balance between visitor 

access and feature preservation is a difficult task. 

Inventory, Monitoring, and/or Research Needs for Hoodoo 

Formation and Present Condition 

• Study the progressive evolution of hoodoos; examine 

morphology and internal stratigraphy and structure for 

interpretive value. 

• Study the impact of solution weathering and freezethaw cycles on fractures. 

• Study the responses of different lithologies to 

weathering and erosion. 

• Study processes affecting landscape evolution 

including: rates of edge migration, erosion, retreat of 

rim, rates of down cutting of streams at the bottom of 

canyons, and aggradation of bottom fill. 

• Study and monitor atmospheric conditions with 

respect to the hydrology of the park. 

• Perform a detailed 3- dimensional cartographic survey 

of the Markagunt Plateau. 

• Study hoodoo fluting to determine if it is vertical or 

follows bedding. 

Paleontologic Potential 

The desert landscape of Cedar Breaks contains more 

than just hoodoos; it contains a record of prolific ancient 

life. Fossils found in geologic formations exposed within 

or near the monument include corals, gastropods 

(snails), pelecypod bivalves (clams, oysters), vertebrates 

(fish, turtles, dinosaurs, birds, and mammals), plants, and 

petrified wood. 

The Upper Cretaceous Straight Cliffs Formation is 

known to have fossil wood and plant fragments (Hatfield 

et al. 2000 a, b). Thin beds of fossiliferous limestones 

contain oysters and are found in lower beds of the 

Straight Cliffs Formation in Cedar Canyon (Hatfield et 

al. 2000 a, b). Vertebrate fossils including fish, turtles, 

and dinosaurs were collected from the Straight Cliffs 

Formation just west of Cedar Breaks (Hatfield et al. 2000 

a, b; Eaton et al. 1999a). Fossil pelecypods, vertebrates, 

leaf fragments and carbonized wood are locally found in 

the Upper Cretaceous Wahweap Sandstone and Upper 

Cretaceous- Paleocene(?) Grand Castle Formation. The 

Paleocene- Eocene Claron Formation is poorly 

fossiliferous although a few pelecypods and gastropods 

have been found (Hatfield et al. 2000 a, b). Bown and 

others (1997) also collected some insect trace fossils from 

the Claron Formation. The lower “variegated” unit of the 

Eocene- Oligocene Brian Head Formation has vertebrate 

fauna including bony fish, ray teeth, and abundant turtle 

fossils 30 miles northeast of Cedar Breaks (Eaton et al. 

1999b). A ray, an unidentified bird, an alligator, and 

ungulate fossils were also collected as were teeth from 

marsupials and rodents. Quaternary insects, plant 

macrofossils, spores and pollen have been recovered 

from pond deposits adjacent to Cedar Breaks and 

radiocarbon dated to 17,000 years bp (Santucci, 2000). 

Specimens found within Cedar Breaks should be 

protected and catalogued for scientific study, and 

preserved for future generations to enhance visitor 

appreciation of the entire monument. 

Inventory, Monitoring, and/or Research Needs for 

Paleontological Potential 

• Perform a comprehensive study of the paleontologic 

resources at Cedar Breaks National Monument 

focusing on Cretaceous, Paleocene, Eocene, and 

Oligocene rocks to determine if fossils are present in 

backcountry areas. 
 CEBR Geologic Resource Evaluation Report 11 

• Inventory all paleontologic specimens collected in the 

monument. If possible, determine the locations of 

specimens removed from the monument that are in 

private collections. 

• Determine localities from which fossils were found, 

document localities, fill out paleontology locality 

forms, and conduct condition assessment to meet 

GPRA goal 1A9 

• Interpret the fossil resources of Cedar Breaks using 

graphics, brochures, and exhibits. Stress the scientific 

importance of fossils and the need to protect and 

preserve fossil resources. 

• Develop appropriate paleontological resource 

monitoring strategies to facilitate scientific research, 

visitor interpretation, and resource management of 

park fossils. 

• Caves sinkholes and springs (such as Arch Springs 

Cave) in the Claron Formation may preserve 

paleontological material, although none is currently 

known. Further investigation is recommended to 

determine their paleontological potential (Santucci et 

al. 2001). 

Faulting and Deformation Processes 

Rocks at Cedar Breaks have undergone multiple phases 

of deformation resulting in folds, faults, joints and other 

fractures compromising the strength of rock units and 

impacting many of the features in the monument. For 

instance, faults and fractures can focus surface runoff 

and by erosion, eventually widen them into gullies. When 

parallel gullies are separated by a jointed rock unit, water 

follows the joints, eroding the rock and ultimately 

separating spires from the rest of the column. 

Deformation is an active and on going process at Cedar 

Breaks. Rocks, being somewhat brittle, respond to 

pressure by developing small- scale fractures and joints. 

Understanding the nature of deformation allows 

geologists to identify areas of weakness in rock where 

weathering and erosion are the greatest. Identifying these 

areas is of importance to a resource manager. 

Inventory, Monitoring, and/or Research Needs for Faulting 

and Deformation Processes 

• Study the role of jointing versus faulting (both strikeslip and thrust faulting) in the evolution of the 

landscape. 

• Study the Markagunt Megabreccia (breccia is a rock, 

composed of cemented rock fragments as a result of 

fracturing, often found in fault zones) near Cedar 

Breaks for regional tectonic implications. 

• Conduct an inventory of all recent fault scarps in the 

area, commonly present in surficial Quaternary 

deposits. 

Mining Issues 

Interest in uranium mining in the area peaked following 

World War II. The principal host rocks for uranium 

exposed near Cedar Breaks are the Triassic Chinle 

Formation and the Jurassic Morrison Formation. 

Abandoned mines pose a threat to an ecosystem and to 

the health and safety of visitors. Surface water and 

groundwater can be contaminated by high 

concentrations of heavy metals leached from the mine 

itself and from mine tailings. Heavy metals may also 

contaminate nearby soils, which in turn can impact plant 

and animal life that live in the soil. Another threat 

specific to uranium mining is that of radon gas exposure. 

Radon is a tasteless, odorless gas produced by the 

radioactive decay of uranium. Radon is a known 

carcinogen that usually concentrates in low- lying areas 

like basements and mineshafts. 

Coal beds are present in the strata of Cedar Breaks. Coal 

indicates that swamps and bogs covered the landscape in 

the past. There are 22 coalfields in Utah found primarily 

in Cretaceous strata such as the Straight Cliffs 

Formation. The major coalfields contain more than a 

billion tons of coal. In southwest Utah, these include the 

Alton, Kaiparowits, and Kolob coalfields, which account 

for over 95 percent of the coal resources in Utah. Minor 

coalfields account for approximately 4 percent of the 

total (State of Utah 2004). 

Cedar Breaks NM has been withdrawn from federal 

mineral leasing laws and the mining law of 1872 

governing mining claims, therefore exploration and 

exploitation of coal and oil and gas is not possible within 

the monument. However, mineral development in the 

area surrounding Cedar Breaks may pose a threat to the 

viewshed and ecosystem of the monument. Since the 

cost of mining coal is directly affected by transportation 

costs, proximity to existing roads and railroads greatly 

influences the siting of coalmines (State of Utah 2004). 

Coal mining and oil and gas production often results in 

new road construction, water pollution, noise, and a 

local population increase. The Surface Mining Control 

and Reclamation Act of 1977 contains specific provisions 

protecting park units from the affects of surface coal 

mining adjacent to park boundaries. 

Inventory, Monitoring, and/or Research Needs for Mining 

Resources and Issues 

• Maintain awareness of the potential encroachment of 

oil and gas exploration and potential surface coal 

mining adjacent to of the park. 

• Perform a thorough investigation of uranium 

occurrence in the monument. This should include 

descriptions of uranium bearing rock units, uranium 

content analysis, and an inventory of locations where 

beds are exposed at the surface and are accessible to 

the public. 

• Complete an inventory of the uranium content of 

recent unconsolidated deposits and soils as well as the 

uranium bearing stratigraphic units. Assess the impacts 

of uranium on fauna and flora in the monument 

• Acquire plugging records of oil and gas wells 

potentially connected to park groundwater systems. 

• Conduct periodic surface and ground water sampling 

as well as soil sampling for uranium. Monitoring the 

mineral content of drinking water is chiefly important. 
12 NPS Geologic Resources Division 

Marysvale Volcanic Field 

Bounding Cedar Breaks to the north is the locally 

extensive Marysvale Volcanic Field. This field formed 

when local extension allowed molten rock to rise 

through the earths crust and penetrate the surface with 

flows and small- scale cones. The volcanic field is 

contemporaneous with other volcanic features on the 

Colorado Plateau including Capulin Volcano. In addition 

to lava flows in the area, the volcanic field spewed vast 

blankets of ash over the landscape that are preserved in 

the youngest rocks at Cedar Breaks today. 

Inventory, Monitoring, and/or Research Needs for Marysvale 

Volcanic Field 

• Date the appropriate minerals applicable to age dating 

lava flows. 

• Determine the amount of volcanic material originally 

present in the monument and how much has been 

subsequently removed by erosion. 

• Use resistivity to locate cavities in flows. Cavities, 

including lava tubes and large vesicles, may contain 

preserved animals. 

• Conduct a detailed study of fractures, faults, and 

bedding within the area. 

• Conduct detailed mapping of volcanic features in the 

volcanic field. 

Wind Erosion and Deposition 

In addition to water, wind is a major force that can 

redistribute soil and soil resources (e.g., litter, organic 

matter, and nutrients) within and among ecosystems. 

Erosion and deposition by wind is important at Cedar 

Breaks National Monument and can be accelerated by 

human activities. 

Accelerated losses of soil and soil biota by erosion may 

indicate a degradation of the ecosystem. Ecosystem 

health is dependent on the retention of these resources. 

In addition, wind erosion and sediment transport may be 

strongly impacted by land- use practices outside the 

monument. Because monument management practices 

limit or prohibit off- road travel, human impacts within 

the monument are primarily associated with off- trail 

hiking in high- use areas. Where livestock grazing or 

trailing is still permitted, accelerated soil erosion can be 

more extensive. 

Inventory, Monitoring, and/or Research Needs for Wind 

Erosion and Deposition 

• Monitor movement of soil materials. 

• Investigate the consequences of soil movement on the 

ecosystem. 

• Investigate the natural range of soil movement in 

relation to landscape configuration and characteristics. 

General Geology 

This report is an attempt to further the long- term goal 

of improving the understanding of geologic processes at 

Cedar Breaks by providing suggestions for future work 

and baseline information, including the attached digital 

geologic map of the park. However, for the scientific 

community and the general public, the geology of Cedar 

Breaks National Monument offers many opportunities to 

further the knowledge of desert erosional processes, 

geologic history, and ancient Native American cultures. 

Inventory, Monitoring, and/or Research Needs for General 

Geology 

• Perform rock color studies. 

• Identify stratigraphic packages bounded by 

unconformities in order to better define past 

depositional systems. 

• Continue to study and implement geographic 

information systems (GIS) technology for 

interpretation, resource management, and 

maintenance. This can be done through interpretive 

mapping, 3- D visualization, virtual field trips, and 

rockfall hazard assessments (McNeil et al. 2002). 

• Obtain GIS data for the unique geologic features of 

Cedar Breaks and catalog these features using a Global 

Positioning System (GPS). This project would also 

allow for future monitoring of erosion associated with 

specific features. 

• Study the glacial and megabreccia deposits around 

Brian Head Peak. Questions remain regarding the 

origin and deposition of the megabreccia. Hatfield and 

others (2000) have addressed some of these questions. 

• Develop educational brochures, graphics and outreach 

programs about the geology of Cedar Breaks, 

emphasizing its unique location relative to the 

transition zone between the Colorado Plateau and 

Basin and Range physiographic provinces. 
 CEBR Geologic Resource Evaluation Report 13 

Geologic Features and Processes 

This section provides descriptions of the most prominent and distinctive geologic features 

and processes in Cedar Breaks National Monument. 

Markagunt Megabreccia 

The Markagunt Megabreccia is exposed in the eastern 

part of Cedar Breaks National Monument. One of 

several large structurally emplaced units in the southern 

High Plateaus, the Markagunt Megabreccia has a 

measured thickness ranging from 5 to 130 feet at 

Blowhard Mountain, southeast of the monument, and in 

surrounding areas (Hatfield et al. 2000). 

The Markagunt Megabreccia was originally thought to 

have been emplaced by repeated landsliding along these 

slip surfaces following tectonic uplift of the Markagunt 

Plateau. However, this interpretation became suspect 

because only Brian Head Mountain rises topographically 

above the breccia in the area and Brian Head is 6 miles 

from the megabreccia at Blowhard Mountain. 

Slip surfaces responsible for the creation of the 

Markagunt Megabreccia occur mainly in the Brian Head 

Formation. Other slip surfaces are in the Bear Valley 

Formation and the Mount Dutton Formation. Both the 

Brian Head Formation and Bear Valley Formation are 

poorly lithified and contain high amounts of volcanic 

ash, making them lithologically and structurally unstable 

units. Slip surfaces in the Mount Dutton Formation are 

in a mudstone breccia unit. 

Typically, landslides are incapable of traveling 6 miles. 

Furthermore, if a landslide had come from the Brian 

Head peak area it would contain clasts of the Leach 

Canyon Formation, which is exposed on the peak. 

However, Leach Canyon clasts do not occur in the 

megabreccia. Hatfield and others (2000) hypothesize 

that the Markagunt Megabreccia was emplaced by 

gravity induced sliding along stratigraphically controlled 

slip surfaces and that this formation once covered Cedar 

Breaks, Blowhard Mountain, and areas at least several 

miles farther south. Testing of this hypothesis continues 

today. 

Hypotheses concerning the causes of the gravity sliding 

also remain to be tested. One hypothesis states that 

sliding was the result of the emplacement of a large 

batholith that caused uplift of the Markagunt Plateau. 

Another suggests that the megabreccia slid off a 

structural dome caused by the emplacement of the Iron 

Peak laccolith located about 15 miles north- northeast of 

Cedar Breaks. A third hypothesis proposes emplacement 

of the megabreccia by gravity sliding off outward 

penetrating thrust sheets generated by the weight and 

collapse of the Marysvale volcanic field to the north 

(Hatfield et al. 2000). More research is needed to test 

these hypotheses. 

Structural Features 

Figure 4 illustrates the gently eastward dip of the 

Markagunt Plateau. The Markagunt Plateau is a fault 

block that has been uplifted and tilted along faults within 

the Hurricane Fault Zone. The Hurricane Fault Zone is a 

major fault zone in Utah with normal fault displacement 

of at least 3,000 m (10,000 feet) in the Cedar City area 

(Hatfield et al. 2000). The Hurricane Fault Zone is an 

example of late Cenozoic basin and range deformation 

caused by extensional tectonics. After millions of years of 

compressive tectonics during the Paleozoic and 

Mesozoic Eras, this was an episode of extensional 

deformation involving the southwestern North 

American margin. 

Compression resulted from the collision of lithospheric 

plates expressed by thrusting as in the Sevier Orogeny 

deforming only near- surface sedimentary strata. Reverse 

faulting as in the Laramide Orogeny, involved 

Precambrian metamorphic and igneous rocks, as well. 

These tectonic events were the result of complex plate 

tectonic movements along the western seaboard of 

North America. 

The High Plateau country of the Colorado Plateau 

contains evidence of both basin and range normal 

faulting and reverse faulting although only normal faults 

have been mapped at Cedar Breaks National Monument. 

The number of faults and the amount of displacement 

along these faults decreases across the High Plateau 

region into the main part of the Colorado Plateau. In 

Cedar Breaks, the normal faults trend north to northeast 

and have displacements of generally less than 100 feet 

(Hatfield et al. 2000). Movement along the Hurricane 

Fault may have begun about 10 million years ago and 

continues today as evidenced by the 1992, 5.9 magnitude 

(local magnitude) earthquake near the town of 

Washington, Utah. 

Erosion of the landscape 

Multicolored cliffs, spires, pinnacles, and other unique 

features at Cedar Breaks were carved by erosion, 

weathering, and mass wasting on the western edge of the 

Markagunt Plateau. Headward erosion of the Ashdown 

Creek drainage cutting into the rim of the Markagunt 

Plateau created much of the topography we see today. 

The freezing and thawing of water in fractures and joints 

breaks rock down by acting as a wedge to pry the rocks 

apart. Chemical alteration and dissolution of the 

minerals in the rock due to percolating groundwater or 

surface water has carved out intricate steps in the Claron 

Formation. With intense rainstorms, weakened and 

loosened rocks move downslope either by gravity alone 

(e.g., talus at the base of cliffs) or by sheetwash and flash 

flooding. 
14 NPS Geologic Resources Division 

Rivers on the Colorado Plateau cut through essentially 

horizontal sedimentary rocks, creating steep cliffs and 

terraces. Resistant rocks such as the Claron Formation 

cap the plateau and overly the softer formations. The 

underlying less resistant rocks are eroded back under the 

lip of the cap rock. Eventually, erosion removes enough 

of the underlying material that the cap rock collapses, 

moving the cliff face ever backward. The rate of cliff face 

retreat at Cedar Breaks is astonishing. This rapid retreat 

is attributed to several factors: 1) the rate of weathering is 

high, 2) the amount of protective vegetative cover is low, 

3) the erosion of soft rocks is rapid, and 4) the rapid 

undercutting of the red limestone member of the Claron 

Formation where the white limestone member acts as a 

cap rock (Lindquist 1980). 

Hoodoo Formation 

This erosional process is responsible for the formation of 

hoodoos at Cedar Breaks. Hoodoos are formed when 

more resistant rock acts as a cap on top of less resistant 

rock forming a column, pinnacle or pillar of rock. The 

formation of hoodoos is in part a function of joints and 

fractures, which accelerates the erosion process. The 

trends of walls and ridges found in Cedar Breaks closely 

follow the trends of the dominant joints within the intact 

rock units (Brox 1961). 

Jointing is not the only control on hoodoo formation, 

especially if the rock is not hard and competent. This 

absence joint control is thought to result from the 

combination of weak beds and the overall rapid rate of 

wall retreat. Because of the extremely high rates of 

erosional retreat and bedrock weathering, it is unlikely 

that the joints offer much added weakness. Hoodoos 

tend to form on the crest of ridges between gullies in the 

red limestone member of the Claron Formation near the 

head of the escarpment. 

Separating the hoodoo from the gully slopes are sharp 

weathering transitions from rapid slope weathering to 

the much slower weathering of the bedrock surfaces 

(Lindquist 1980). Any hoodoo formation in the slopeforming member is thus a self- enhancing mechanism 

(Engineers International Inc. 1980). The presence of 

sedimentary layers of alternating resistance to erosion 

appears to be crucial in hoodoo development. This 

variation and alternation of resistant layers is a primary 

feature of the Claron Formation (Lindquist, 1980). 

As in nearby Bryce Canyon National Park, the pinnacles 

of Cedar Breaks vary in height from less than 12 m (40 ft) 

to 61 m (200 ft) or more. The eroded limestone forms an 

intricate landscape of arches, spires, pinnacles, and 

natural bridges (Engineers International, Inc. 1980). 

Some hoodoos extend from the escarpment at right 

angles and are like walls. Lindquist (1980) called these 

“primary hoodoos.” Secondary hoodoos extend at 

various angles from primary hoodoos or slopes leading 

to primary hoodoos. Ridge hoodoos form on ridge crests 

some distance (100’s of meters) from the primary 

escarpment. Hoodoos can form complexes as clusters of 

shapes with a radiating configuration. 

Other Features 

• The tapestry of colors is another feature that 

contributes to the unique appearance of the 

monument. Although the exact coloring agents in the 

rock still need to be identified, the colors are currently 

believed to be due to various amounts of iron and 

manganese compounds (Hatfield et al. 2000). 

• Cedar Breaks is a unique location on the Colorado 

Plateau where a visitor has a splendid view of the Basin 

and Range landscape to the west while standing on a 

plateau of nearly flat- lying rock layers. This transition 

in structure and topographic expression from one 

geologic province to another is further illustrated by 

the variety of volcanic and sedimentary rock units 

derived from various source areas on the Colorado 

Plateau.
 CEBR Geologic Resource Evaluation Report 15 

Map Unit Properties 

This section provides a description for and identifies many characteristics of the map 

units that appear on the digital geologic map of Cedar Breaks National Monument. The 

table is highly generalized and is provided for informational purposes only. Ground 

disturbing activities should not be permitted or denied on the basis of information 

contained in this table. More detailed unit descriptions can be found in the help files that 

accompany the digital geologic map or by contacting the NPS Geologic Resources 

Division. 

Mesozoic rocks underlie Cedar Breaks National 

Monument almost entirely. Capping the high points are 

Tertiary and Quaternary rocks. Because of intense 

erosion, these rocks are on striking display. 

The Upper Cretaceous Straight Cliffs Formation, the 

oldest formation in Cedar Breaks, is derived from a 

mixture of sand, mud, limy ooze, and organic matter 

which lithified into a coal- rich unit. The sandstones, 

mudstones, and siltstones of the Grand Castle and 

Wahweap Sandstones followed this deposition. 

The Tertiary Claron Formation is the result of local 

basins filling with sediments. The Brian Head Formation 

was deposited over the Claron. Erosion of these units 

during uplift formed the spindly hoodoos, 

amphitheatres, klippes, and other fantastic 

geomorphological shapes discussed above. 

Volcanic eruptions throughout the area are responsible 

for the tuffaceous layers of the Oligocene Isom 

Formation and Miocene Leach Canyon Formations. The 

mysterious, intensely deformed, chaotic mass of the 

Markagunt Megabreccia, also of Miocene age, lies above 

the tuff deposits preceding another volcanic event. This 

event left basalt and other mafic lava flows in the area. 

Pleistocene glaciation and other geomorphological 

agents, such as streams and landslides, have left recent 

Quaternary age deposits on the landscape of Cedar 

Breaks National Monument. 

The following table presents the stratigraphic column of 

Cedar Breaks and an itemized list of features associated 

with each map unit. This table lists the properties specific 

to each unit including: map symbol, name, description, 

resistance to erosion, suitability for development, 

hazards, potential paleontologic resources, cultural and 

mineral resources, potential karst issues, potential 

recreational use, and global significance. 

For further information on map units and other ancillary 

map information, please consult the Windows help file: 

CEBRGLG.hlp (included on CD).
Map Unit Properties Table 

Age Unit Name (Symbol) Features and Description Erosion Resistance Suitability for Development Hazards Potential Paleontologic Resources Potential Cultural Resources 

Artificial fill (af) Man- made fill deposits, mostly for dams and highways 

Quaternary 

Alluvium (Qal), alluvialterrace deposits (Qal1), sheet wash alluvium (Qac), colluvium (Qc), Volcanic gravel colluvium (Qcv), peat (Qo), eolian deposits (Qes), landslide deposits (Qms), alluvial fan deposits (Qf), older talus and colluvium (Qmt2), older alluvium (Qa), and older landslide deposits (QTl) 

Unconsolidated sediments deposited in eolian, alluvial, fan, and landslides; includes peat deposits. Pleistocene and Holocene landslide deposits (Qms), colluvium (Qc), alluvial fans (Qf), and alluvium (Qal) are common in CEBR (Hatfield et al., 2000). Landslides in the Brian Head Formation are especially common. Alpine Pond fills a depression formed by a landslide, and about 50 feet of Isom Fm. blocks are exposed along the landslide scarp above the pond. Peat (Qo) has formed from Pleistocene and Holocene bog deposits that occur in and near the monument. Vegetation has stabilized eolian dunes (Qes) just east of the Cedar Breaks rim (Hatfield et al., 2000). 

Low to very 

low 

Units are suitable for most development unless exposed on a slope where unconsolidated deposits are prone to fail. High permeability of units makes some waste facility development problematic. Presence of any altered volcanics (as swelling clays) may make road and trail development risky. 

High landslide potential as well as mass wasting and other slumping, especially when units are water saturated. 

Local fossil remains; many likely washed in from other units 

Tools, 

arrowheads and 

other artifacts 

Quaternary Basalt (Qb), and olivine- plagioclase mafic volcanic rock: lava flows (Qbf1) 

Black & gray, vesicular, generally crystalline poor, basalt. Some units with visible crystals of olivine and plagioclase present as lava flows. Resistant basalt forms lava flows, flow breccia, dikes, and cinder cones just east of CEBR; vegetated flows probably Pleistocene in age; those without vegetation may be Holocene. 

Moderate 

to high 

Units are suitable for most development unless high fracture density is present. Any altered clays. associated with the volcanics may lead to unstable road, trail, and building foundations. 

Rockfall potential when exposed on a cliff face. 

None None documented 

Tertiary 

(Miocene) Markagunt Megabreccia (Tm) 

Angular clasts and broken masses of Brian Head, Wah Wah Springs (not in CEBR), Isom, Bear Valley (not in CEBR), and Mount Dutton (not in CEBR) Formations form the poorly exposed, structurally chaotic assemblage of Markagunt Megabreccia; rock masses, house- to cityblock- sized, set in a matrix of sheared and folded rocks of same units. Some masses are as large as 1 square mile. 20- 46 m (65-150 ft) thick. 

Low 

Most permanent development on this unit is not recommended due to the highly fractured nature of the breccia. 

Rockfall and landslide potential high; highly fractured and deformed unit. 

Fragments 

from other 

units 

None 

documented 

Tertiary 

(Miocene) Leach Canyon Formation (Tl) 

The distinctive, rhyolite ash- flow tuffs of Miocene age (23.8 Ma); cooling units may be associated with the Caliente caldera complex straddling Nevada- Utah border about 60 miles to the west. Leach Canyon tuffs did not extend past eastern section of the Markagunt Plateau. Phenocrysts make up about 10 to 20 % of the crystal- poor tuff; ubiquitous brownish- red rhyolite lithic clasts, rounded gas cavities lined with yellow vapor- phase minerals, and abundant white collapsed pumice fragments; 26 m (85 ft) thick. 

Moderate 

Poorly welded; friable and weak for road & buildings foundations, trails and camp sites; variable permeability may allow waste facility development. 

Highly friable; easily eroded; slides and slumping probable. 

None None documented 
Age Unit Name (Symbol) Features and Description Erosion Resistance Suitability for Development Hazards Potential Paleontologic Resources Potential Cultural Resources 

Tertiary 

(Oligocene) Isom Formation (Ti) 

Three members: the Blue Meadows Tuff member, Baldhills Tuff member (may be 650 feet thick), and Hole- in- the- Wall Tuff member. North of CEBR, Baldhills Tuff member forms at least three cooling units totaling about 80 feet thick; units consist of dark- gray, black, and brick red tuff with long linear vesicles and local breccia; formation generally composed of resistant, reddish- brown to dark- gray, crystal- poor, densely welded, trachytic ash- flow tuffs; 24 m (80+ ft) thick 

Moderate 

to high 

Poorly welded; friable and weak for road & buildings foundations, trails and camp sites; variable permeability may allow waste facility development. 

Degree of welding highly heterogeneous; erosion, slides and slumping probable. 

None None documented 

Tertiary 

(U. Eocene – Oligocene) Brian Head Formation (Tbh) 

Three poorly exposed units: 1) lower soft, reddish- brown, pink, & reddish- orange, non- tuffaceous sandstone & conglomerate with some siltstone, claystone, & micritic limestone; 2) gray, greenish- gray, yellowish- gray, bioturbated beds of volcaniclastic clayey sandstone, conglomeratic sandstone, claystone, micritic limestone, & air fall tuff; 3) upper heterogeneous unit of volcanic mudflow breccia, immature volcanic sandstone and conglomerate, mafic lava flows, and ashflow tuff; total thickness: 213 m (700 ft). 

Moderate 

Variable in rock type, degree of consolidation and stability; careful mapping and surveying recommended before development; some swelling clay. 

High potential for rockfalls and landslides especially when exposed on a slope or undercut by erosion of underlying layers 

Vertebrates 

Plants 

Chert may have 

provided tool 

material in this 

unit 

Tertiary 

(Eocene) Claron Formation, White Member (Tcw) 

Lake & river sediments; cliff of white & light- orange, micritic limestone; yellowishgray to light- brown, interbedded mudstone and fine- to medium- grained sandstone; cliff of white, light- yellowishgray, and light- orange, micritic limestone; forms impressive, west- facing scarp marking the rim of the central Markagunt Plateau; about 110 m (360 ft) thick. 

Moderate 

Hoodoos and other erosional and karst features are abundant in this unit making development a poor candidate for development. 

Slumping, sliding and rockfall potential when highly eroded or undercut from lower units on a slope face 

Locally abundant palynomorphs, insects and assorted gastropods 

Erosional formations often had spiritual significance to ancient Native American tribes 

Tertiary 

(Paleocene - Eocene) Claron Formation, Red Member (Tcr) 

Resistant pink, red, & reddish- orange, argillaceous, sandy micritic limestone; resistant reddish- tan & pink cross- bedded sandstone; soft, red and pink silty mudstone with minor lenticular, gray, pink, reddish- tan, resistant conglomerate and conglomeratic sandstone; 65- foot limestone at base. Thin- bedded limestone, cross- bedded sandstone, and lenticular conglomerate beds are more resistant than soft mudstone beds; veinlets of sparry calcite that represent algal filaments branch through the limestone also containing vertical burrow fillings and stylolites. Shallow caves and local springs found in 65- foot limestone bed at base; approximately 396 m (1300 ft) thick. 

Moderate 

Hoodoos and other erosional and karst features abundant; a poor candidate for development. 

Severe erosion hazards; landslide potential rockfall potential, especially where exposed on steep slopes 

Pelecypods, gastropods and other trace fossils abundant. 

Hoodoos and other erosional formations had significant spiritual significance to local ancient Native American peoples 
Age Unit Name (Symbol) Features and Description Erosion Resistance Suitability for Development Hazards Potential Paleontologic Resources Potential Cultural Resources 

Upper Cretaceous –Tertiary (Paleocene) Grand Castle and Wahweap Sandstones (TKgw) 

Mostly sandstone in upper part of Wahweap; rest of formation poorly exposed, interbedded soft, mostly brownish- gray, olive- brown, and reddishbrown mudstone with minor sandstone and siltstone. Thin- bedded siltstone and fine- grained sandstone is gray, black, and grayish- orange; sandstone locally crossbedded (Hatfield et al., 2000). Carbonized fossil wood, leaf impressions, and spherical calcareous, limonitic concretions present; lower part of the unit is a poorly exposed friable, cross- bedded sandstone; light gray to light yellowish- gray and locally interbedded with underlying Wahweap Sandstone; upper part is a ledge of fine- to coarse- grained, cross- bedded, argillaceous, cherty sandstone and smallpebble mudstone conglomerate. The angular, poorly to moderately sorted sandstone is yellowish- brown, orangegray, and white “salt- and- pepper;” may correlate with Grand Castle Fm.; combined thickness averages 305 m (1000+ ft). 

Moderate 

to high 

Suitable for most forms of development unless highly fractured or undercut on a slope; variable in rock type; careful mapping and development needed; mud- rich units & poorly consolidated units will compromise stability of structures and roads. 

High variability of rock types may create rockfalls when a resistant unit overlies a less resistant unit; sliding potential in mud- rich or poorly consolidated layers. 

Leaf impressions, some fossil wood, pelecypods and other assorted vertebrate fossils found regionally 

Possible tool 

material 

L cp

Upper Cretaceous Straight Cliffs Formation, upper part (Kscu) 

Soft, light- gray, yellowish- gray, light yellowish- brown, reddish- brown, & brownish- gray mudstone with thin beds of lenticular, fine- to medium- grained sandstone; sandstone thickens to west where lower unit forms gray cliffs of marine sandstone interbedded with thin beds of fossiliferous oyster- bearing limestone and coal; oyster- bearing limestone and coal to the west of CEBR; about 366 m (1200 ft) thick. 

High 

Suitable for most forms of development unless highly fractured or undercut on a slope exposure. 

Rockfall potential 

when exposed on 

a cliff face 

Some fossil wood, oysters, clams and assorted gastropods 

Provided building material for ancient Native Americans; petroglyphs present at some locales 

Llcp
 CEBR Geologic Resource Evaluation Report 19 

Geologic History 

This section highlights the map units (i.e., rocks and unconsolidated deposits) that occur 

in Cedar Breaks National Monument and puts them in a geologic context in terms of the 

environment in which they were deposited and the timing of geologic events that created 

the present landscape. 

The geologic story of Cedar Breaks National Monument 

begins in the Late Cretaceous (figure 5). Dinosaurs 

roamed southwestern and western Utah, feeding on lush 

vegetation while other vertebrates and abundant 

invertebrate inhabited the ocean and near shore 

environments to the east of Cedar Breaks. As the Sevier 

Orogeny advanced from the west, sedimentary rocks that 

had formed in shallow, offshore marine environments 

were folded and uplifted into mountain ranges. 

In complement to the uplifting mountains, the Western 

Interior Basin, a shallow north- south trending basin, 

formed east of the thrust belt. While the mountains rose 

in the west and the Western Interior Basin expanded, the 

Gulf of Mexico separating North and South America rift 

open in the south, and marine water began flowing 

northward into the basin. At the same time, marine water 

began to advance onto the continent from the Arctic 

region. As the shallow seas advanced onto the continent, 

currents redistributed sediment deposited by river 

systems in much the same way sediments are 

redistributed along the shorelines of North America 

today. As more sediment was shed from the continent 

and deposited into the basin, the weight of the sediment 

caused the basin to subside. 

The seas advanced and retreated many times during the 

Cretaceous until the most extensive interior seaway ever 

recorded drowned much of western North America 

(figure 6). The Western Interior Seaway filled an elongate 

basin that extended from today’s Gulf of Mexico to the 

Arctic Ocean, a distance of about 4827 km (3,000 mi) 

(Kauffman 1977). 

In the Cretaceous the western margin of the seaway 

coincided with the active Sevier orogenic belt, but the 

eastern margin was part of the low- lying, stable platform 

ramp in what today coincides with Nebraska and Kansas. 

Consequently, sedimentation into the basin from the 

rising mountains on the western margin was rapid 

compared to the slow sedimentation into the basin from 

the craton on the eastern margin. Rapid sedimentation 

led to further sediment loading and downwarping along 

the western margin. 

By the Late Cretaceous, the present Four- Corners area 

had migrated northward into a subtropical climatic zone. 

Although the seaway was not physically restricted at 

either end, water circulation appears to have been 

periodically disrupted. A variety of depositional 

environments existed throughout the basin as sea level 

rose and fell. These included brackish estuaries, deltas, 

beaches, deep water, coal swamps, and fluvial systems. 

Over time, changes in depositional environment with 

changing sea level were recorded in the vertical section 

of rocks and fossils. 

The Straight Cliffs Formation and Grand CastleWahweap Sandstone record a gradual change from 

nearshore, mostly shallow marine environments in the 

Straight Cliffs to fluvial (river) and lake deposition in the 

Grand Castle and Wahweap Sandstone. In effect, these 

Late Cretaceous to early Tertiary rocks record the Sevier 

orogenic deformation and its evolution into Laramidestyle deformation (Goldstrand 1990). For about 35 

million years during the Laramide Orogeny, from 

roughly 70 Ma to 35 Ma, the collision of the tectonic 

plates transformed the extensive basin of the Cretaceous 

Interior Seaway into smaller, internally drained, nonmarine, intermontane basins (figure 7) (Goldstrand 1990; 

Ott 1999; Graham et al. 2002). This style, contrasting with 

earlier Sevier deformation, involved thick, basementcored uplifts along thrust faults, and extensive folding. 

According to Gilbert (1877): 

“It seems as though the crust of the earth had been 

divided into great blocks, each many miles in extent, 

which were moved from their original positions in 

various ways. Some were carried up and others down, 

and the majority were left higher at one margin than at 

the other. But although they moved independently, 

they were not cleft asunder. The strata remained 

continuous, and were flexed instead of faulted at the 

margins of the blocks.” 

The Claron Formation includes fluvial, deltaic, and 

lacustrine sediments, deposited after the Sevier Orogeny 

ended. These sediments record deposition in wellaerated lakes and streams in a large, stable intermontane 

basin bounded by the basement- cored uplifts produced 

during the Laramide Orogeny (figure 8) (Goldstrand 

1990; Ott 1999; Hatfield et al. 2000). 

The lower red member of the Claron Formation was 

deposited in a shallow, low- energy, low gradient lake 

margin, resulting in the slow alteration and pedogenesis 

(extreme bioturbation) of the primary sediments. The 

upper white member signals the reestablishments of 

continuous lacustrine sedimentation punctuated by rare 

pedogenic (soil forming) events (Ott 1999). The upper 

layers, which might bear record of the desiccation of the 

lacustrine environment, have been eroded from the 

Cedar Breaks area. 
20 NPS Geologic Resources Division 

The angle at which the Pacific lithospheric plate was 

being subducted beneath the North American plate 

changed in the Eocene and cut off the Laramide 

Orogeny. The shallow basins continued to be filled with 

lake and stream deposits that eventually became the 

Brian Head Formation (Eocene and Oligocene). The 

lower part of the Brian Head Formation reflects a 

continuation of the relatively passive environmental 

setting that began in the Late Cretaceous. Dinosaurs 

were absent and streams that traversed the hummocky 

topography carried silt and mud that slowly settled into 

the remaining lakes. 

The tuffaceous sediments in the middle parts of the Brian 

Head Formation mark the beginning of extensive 

volcanic eruptions to the west and north that impacted 

not only Utah but also the entire margin of western 

North America. About 32 Ma (lower Oligocene), 

clustered volcanoes explosively erupted in 

stratovolcanoes that became the Marysvale volcanic 

field. The southern margin of this volcanic field lies just 

north of the monument. 

Explosive andesitic volcanism dominated the area to the 

west during Oligocene and early Miocene time and 

probably inundated both the Cedar Breaks and Zion 

regions with hundreds of feet of volcanic ash (figure 9) 

(Biek et al. 2000; Hatfield et al. 2000). Like the ash 

deposits from Mt. St. Helens, the Tertiary volcanic ash 

erupted as a hot mixture of volcanic gases and tephra 

forming the ash- flow tuffs of the Isom Formation (27 

Ma; Oligocene) and the Leach Canyon Formation (24 

Ma; Miocene). 

Coincident with basaltic volcanism, the north- striking 

faults of the ancestral Hurricane fault zone ruptured the 

surface. North of Cedar Breaks, deep grabens developed 

by west- northwest striking faults active about 26 Ma. 

These grabens filled with eolian sand, volcanic ash, and 

mafic lava flows seen today as the Bear Valley Formation 

(not exposed in the monument) (Hatfield et al. 2000). 

Volcanic mudflows (lahars) surged down the flanks of 

the denuded volcanoes of the Marysvale volcanic field 

and buried the Bear Valley Formation. These became the 

volcanic breccias of the Mount Dutton Formation (not 

exposed in the monument). 

During the Lower Miocene (22 to 20 Ma), the Markagunt 

Megabreccia moved southward into the Cedar Breaks 

area. This movement was triggered either by earthquakes 

causing movement on giant gravity- slide sheets or by 

compressive forces that caused shallow thrust sheets in 

and north of the monument to rupture the surface. The 

megabreccia slid along subhorizontal shear planes in 

incompetent rock units such as the Brian Head 

Formation. 

The Basin and Range extensional tectonic episode began 

in southwestern Utah about 20 Ma although most basin 

and range faulting began about 10 Ma (Hatfield et al. 

2000). The major result of this extension was creation of 

the Basin and Range Province to the west. In this period 

of extension, the Hurricane Fault Zone underwent its 

most recent episode of faulting and the High Plateaus 

were blocked out. Extensional tectonics have continued 

to the present. 

Uplift of the Markagunt Plateau was accompanied by 

extensive erosion. Rocks were loosened by physical 

weathering such as frost action and root growth and by 

chemical weathering such as the dissolution of the 

calcium carbonate cement that binds the particles 

together to form sedimentary rock. Once loosened, the 

particles cascade downslope by the force of gravity or are 

removed by runoff from rain or melting snow. Rivers 

also cut into the cliffs by headward erosion. Headward 

erosion carves shallow, elongate indentations or 

amphitheaters into the edge of a plateau. Not all rocks 

erode in the same manner. Some are more resistant than 

others. This selective erosion of less resistant rock is 

called differential erosion. 

At Cedar Breaks National Monument, the erosion of the 

fault scarp bordering the Markagunt Plateau has caused 

the western margin to retreat several miles eastward. 

During the Pleistocene, the highest parts of the plateau in 

Cedar Breaks were scoured and scraped by glaciers. 

Physical and chemical weathering including mass 

wasting by landslides, rock falls and soil creep continue 

to erode the plateau’s rim and push it farther eastward. 

The topography we see now at Cedar Breaks will slowly 

disappear as the landscape continues to evolve. 

The Quaternary Period is subdivided into two epochs: 

1) Pleistocene, which ranges from about 1.6 Ma to 10,000 

years before present (B.P.), and 2) Holocene Epoch that 

extends from 10,000 years B.P. to the present. The 

Pleistocene Epoch is known as the Ice Age and is marked 

by multiple episodes of continental and alpine glaciation. 

Continental glaciers, thousands of feet thick, advanced 

and retreated over approximately 100,000- year cycles. 

Huge volumes of water were stored in the glaciers during 

glacial periods so that sea level dropped as much as 91 m 

(300 ft) (Fillmore 2000). The carving of a rugged 

mountain landscape by streams, frost action, and glaciers 

has been the principal geologic activity in this region 

from late Tertiary time to the present. 

The Holocene is the Age of Humans and human impact 

on the global ecosystem is complex. With the retreat of 

the glaciers and the end of widespread glaciation about 

12,000 years ago, the climate continued to warm and 

global sea level rose. In some local areas (e.g., the coast of 

Maine), however, relative sea level lowered as the land 

rebounded from the weight of the glaciers. Local 

tectonism, sediment input, global warming, and global 

cooling are some of the factors affecting global sea level 

The relative importance of these factors, and the impacts 

that humans have on them, continue to be debated today 

(Graham et al. 2002). 

Geologically, the High Plateaus area has not changed 

much during the Holocene. The area has been subjected 

to some extension and uplift associated with the Rio 

Grande Rift, and streams have carved new landscapes 
 CEBR Geologic Resource Evaluation Report 21 

since the end of the Ice Age. However this is geologically 

a very brief period of time. Figure 10 summarizes the 

geologic history from the Proterozoic to the present at 

Cedar Breaks. 

The following references provide additional information 

regarding geologic principles, the geology of Cedar 

Breaks National Monument, and background 

information on the monument. 

• Plummer, C. C., McGeary, D., and Carlson, D. H., 

1996, Physical Geology: McGraw- Hill, 577 p. 

• Chernicoff, S. and Venkatakrishnan, R., 1995, Geology, 

Worth Publishers, 593 p. 

• Tarbuck, E. J., Lutgens, F. K., and Dennis, T., 2001, 

Earth: An Introduction to Physical Geology: PrenticeHall, 7th edition, 688 p. 

• Hatfield, S.C., Rowley, P.D., Sable, E.G., Maxwell, D.J., 

Cox, B.V., McKell, M.D., Kiel, D.E., 2000, Geology of 

Cedar Breaks National Monument, in D.A. Sprinkel, 

T.C. Chidsey, Jr., and P.B. Anderson, eds., Geology of 

Utah’s Parks and Monuments: Utah Geological 

Association, Publication 28, p. 139- 154. 

• Kiver, E.P. and Harris, D.V., 1999, Geology of U.S. 

Parklands: John Wiley & Sons, Inc., New York, 5th

Edition, p. 522- 530. 
22 NPS Geologic Resources Division 

Figure 5. Geologic time scale; adapted from the U.S. Geological Survey. Red lines indicate major unconformities between eras. 

Included are major events in life history and tectonic events occurring on the North American continent. Absolute ages shown are in 

millions of years. 
 CEBR Geologic Resource Evaluation Report 23 

Figure 6. Location of the Cretaceous Period, Western Interior Seaway. Shaded areas indicate land above sea level. Shoreline migrated 

east and west periodically through time. North indicates the Cretaceous north. Modified from Rice and Shurr (1983). 
24 NPS Geologic Resources Division 

Figure 7. Location of Cedar Breaks National Monument on a tectonic map showing Laramide-age structures on the Colorado Plateau.

The map illustrates the anastamosing nature of the basement-cored arches (regional-scale anticlines) and the spatial relationships 

with the adjacent thrust belt, Colorado Plateau, and North American craton. The ‘Thrust Belt’ marks the eastern extent of the Sevier 

Orogeny. From Gregson and Chure, 2000. 
 CEBR Geologic Resource Evaluation Report 25 

Figure 8. Early post-Laramide map showing the probable location of the continental divide, major depositional basins, erosional

features, and stream systems in the western U.S. Light gray areas denote basins (note Claron Basin), dark gray areas indicate 

highlands and arrows indicate probable directions of sediment transport into the basins and away from the continental divide. SDC, 

Sangre de Cristo Mountains; SJ, San Juan Mountains. Modified from Christiansen and others, 1992. 
26 NPS Geologic Resources Division 

Figure 9. Tertiary (primarily Miocene) volcanic centers in southern Utah and Nevada. The ages of the basalt systematically decrease 

from west to east, suggesting the presence of a fixed hot spot in the mantle. Modified from Fillmore, 2000, and Nelson and Tingey, 

1997. 
 CEBR Geologic Resource Evaluation Report 27 

Figure 10. Generalized graphic overview of geologic evolution of Utah from the Archean Eon to the Holocene Epoch (adapted from 

Hintze 1988). 
28 NPS Geologic Resources Division 

References 

This section provides a listing of references cited in this report. It also contains general 

references that may be of use to resource managers. A more complete geologic 

bibliography is available and can be obtained through the NPS Geologic Resources 

Division. 

Baars, D.L., Bartleson, B.L., Chapin, C.E., Curtis, B.F., De 

Voto R.H., Everett, J.R., Johnson, R.C., Molenaar, 

D.M., Peterson, F., Schenk, C.J., Love, J.D., Merin, 

I;.S., Rose, P.R., Ryder, R.T., Waechter, N.B., and 

Woodward, L.A., 1988, Basins of the Rocky Mountain 

region, in L.L. Sloss, ed., Sedimentary Cover – North 

American Craton: U.S.: Geological Society of America, 

The Geology of North America, Volume D- 2, p. 109-

220. 

Biek, R.F., Willis, G.C., Hylland, M.D., and Doelling, 

H.H., 2000, Geology of Zion National Park, Utah, in 

D.A. Sprinkel, T.C. Chidsey, Jr., and P.B. Anderson, 

eds., Geology of Utah’s Parks and Monuments: Utah 

Geological Association Publication 28, p. 107- 138. 

Bown, T. M., S. T. Hasiotis, J. F. Genise, F. Maldonado, 

and E. M. Brouwers. 1997. Trace fossils of 

Hymenoptera and other insects, and 

paleoenvironments of the Claron Formation 

(Paleocene and Eocene), southwestern Utah. Pages 41-

58 in F. Maldonado and L. D. Nealey (editors). 

Geologic studies in the Basin and Range- Colorado 

Plateau transition in southeastern Nevada, 

southeastern Utah, and northwestern Arizona, 1995. 

U.S. Geological Survey Bulletin 2153. 

Brox, G.S., 1961, The geology (Wasatch Formation, 

Eocene) and erosional development of northern Bryce 

Canyon National Park, (Garfield County, Utah). 

Master’s thesis, University of Utah, Salt Lake City, UT, 

70 pp. 

Chenoweth, W. L., 1996, The Uranium industry in the 

Paradox Basin, in A.C. Huffman, Jr., W.R. Lund, and 

L.H. Godwin, eds., Geology and Resources of the 

Paradox Basin: Utah Geological Association 

Guidebook 25, 1996 Field Symposium, p. 95- 108. 

De Courten, F., 1994, Shadows of time – the geology of 

Bryce Canyon National Park. Bryce Canyon Natural 

History Association, Bryce Canyon, Utah, 128 pp. 

Dutton, C.E., 1880, Report on the geology of the High 

Plateaus of Utah. U.S. Geographic and Geological 

Survey of the Rocky Mountain region (Powell), 307 pp. 

Eaton, J. G., S. Diem, J. D. Archibald, C. Schierup, and H. 

Munk. 1999a. Vertebrate paleontology of the Upper 

Cretaceous roks of the Markagunt Plateau, 

southwestern Utah. Pages 323- 334 in Gillette, D. D. 

(editor). Vertebrate Paleontology in Utah. Utah 

Geological Survey Miscellaneous Publication 99- 1. 

Eaton, J. G., J. H. Hutchison, P. A. Holroyd, W. W. 

Korth, and P. M. Goldstrand. 1999b. Vertebrates of the 

Turtle Basin local fauna, Middle Eocene, Sevier 

Plateau, South- Central Utah. Pages 463- 468 in 

Gillette, D. D. (editor). Vertebrate Paleontology in 

Utah. Utah Geological Survey Miscellaneous 

Publication 99- 1. 

Fillmore, R., 2000, The Geology of the Parks, 

Monuments and Wildlands of Southern Utah: The 

University of Utah Press, 268 p. 

Goldstrand, P.M., 1990, Stratigraphy and paleogeography 

of Late Cretaceous and Paleogene rocks of southwest 

Utah: Utah Geological and Mineral Survey 

Miscellaneous Publication 90- 2, 58 p. 

Goldstrand, P.M., 1994, Tectonic development of Upper 

Cretaceous to Eocene strata of southwestern Utah: 

Geological Society of American Bulletin, v. 106, no. 1, p. 

145- 154. 

Graham, J. P., Thornberry, T. L., and O’Meara, S. A., 

2002, Geologic Resources Inventory for Capitol Reef 

National Park: Inventory and Monitoring Program, 

National Park Service, Fort Collins, CO., 328 p. 

Gregory, H.E., 1950, Geology and Geography of the Zion 

Park Region Utah and Arizona: U.S.G.S. Professional 

Paper 220, 200 p. 

Gregory, H.E., 1951, The geology and geography of the 

Paunsaugunt region, Utah: USGS Professional Paper 

226, 116 p. 

Gregory, H.E., Moore, R.C., 1931, The Kaiparowits 

region, a geographical and geologic reconnaissance of 

parts of Utah and Arizona. U.S. Geological Survey 

Professional Paper 164, 161 pp. 

Hatfield, S. C., P. D. Rowley, E. G. Sable, D. J. Maxwell, 

B. V. Cox, M. D. McKell, and D. E. Kiel. 2000a. 

Geology of Cedar Breaks National Monument, Utah. 

in Sprinkel, D. A., T. C. Chidsey, Jr. and P. B. Anderson 

(editors). Geology of Utah’s Parks and Monuments. 

Utah Geological Association Publication 28. 

Hatfield, S. C., P. D. Rowley, E. G. Sable, D. J. Maxwell, 

B. V. Cox, M. D. McKell, and D. E. Kiel. 2000b. 

Geologic Road Log of Cedar Breaks National 

Monument, Utah. in Anderson, P. B. and D. A. 

Sprinkel, (editors). Geologic Road, Trail, and Lake 

Guides to Utah’s Parks and Monuments. Utah 

Geological Association Publication 29. 
 CEBR Geologic Resource Evaluation Report 29 

Hintze, L.F., 1988, 1993, Geologic history of Utah: 

Brigham Young University Studies Special Publication 

7, 202 p. 

Kauffman, E. G., 1977, Geological and biological 

overview: Western Interior Cretaceous Basin: 

Mountain Geologist, v. 14, p. 75- 99. 

Kelley, V.C., 1955, Monoclines of the Colorado Plateau. 

Geological Society of America Bulletin, vol. 66, pp. 

789- 804. 

Kelley, V.C., Clinton, N.J., 1960, Fracture systems and 

tectonic elements of the Colorado Plateau. University 

of New Mexico Publications in Geology, no. 6, 104 pp. 

Kiver, E.P. and Harris, D.V., 1999, Geology of U.S. 

Parklands: John Wiley & Sons, Inc., 5th edition, p. 455-

466. 

Lindquist, R.C., 1980, Slope processes and forms at Bryce 

Canyon National Park. Dissertation, University of 

Utah, Salt Lake City, UT, 134 pp. 

Nelson, S.T., and Tingey, D.G., 1997, Time- transgressive 

and extension- related basaltic volcanism in southwest 

Utah and vicinity: Geological Society of America 

Bulletin 109, p. 1249- 1265. 

Nuccio, V. F. and Condon, S. M., 1996, Burial and 

thermal history of the Paradox Basin, Utah and 

Colorado, and petroleum potential of the Middle 

Pennsylvanian Paradox Formation, in A.C. Huffman, 

Jr., W.R. Lund, and L.H. Godwin, eds., Geology and 

Resources of the Paradox Basin: Utah Geological 

Association Guidebook 25, 1996 Field Symposium, p. 

57- 76. 

Ott, A.L., 1999, Detailed stratigraphy and stable isotope 

analysis of the Claron Formation, Bryce Canyon 

National Park, southwestern Utah. Master’s Thesis, 

Washington State University, Pullman, WA. 

Rice, D. D. and Shurr, G. W., 1983, Patterns of 

sedimentation and paleogeography across the Western 

Interior Seaway during time of deposition of Upper 

Cretaceous Eagle Sandstone and equivalent rocks, 

northern Great Plains, in M. W. Reynolds and E. D. 

Dolly, eds., Mesozoic Paleogeography of the WestCentral United States: Rocky Mountain Section, 

SEPM (Society for Sedimentary Geology), p. 337- 358. 

Santucci, Vincent L., Kenworthy, Jason, and Kerbo, Ron, 

2001, An inventory of paleontological resources 

associated with National Park Service Caves, Geologic 

Resources Division Technical Report 01/02, p.10. 

State of Utah, 2004, Coal Resources. 

http://www.planning.utah.gov/CRMPCoalResources.

htm 

Swan, F.H., III, Schwartz, D.P., Cluff, L.S., 1980, 

Recurrence of moderate to large magnitude earthquakes 

produced by surface faulting on the Wasatch fault zone, 

Utah. Bulletin Seismological Society of America, vol. 70, 

pp. 1431- 1432. 
30 NPS Geologic Resources Division 
 CEBR Geologic Resource Evaluation Report 31 

Appendix A: Geologic Map Graphic 

The following page provides a preview or “snapshot” of the geologic map for Cedar 

Breaks National Monument. For a poster size PDF of this map or for digital geologic 

map data, please see the included CD or visit the GRE publications webpage: 

http://www2.nature.nps.gov/geology/inventory/gre_publications.cfm 

 CEBR Geologic Resource Evaluation Report 33 

Appendix B: Scoping Summary 

The following excerpts are from the GRE scoping summary for Cedar Breaks National 

Monument. The scoping meeting occurred on July 15- 16, 1999; therefore, the contact 

information and Web addresses referred to herein may be outdated. Please contact the 

Geologic Resources Division for current information. 

Executive Summary 

An evaluation workshop was held at Cedar Breaks 

National Monument on July 15- 16, 1999 to view and 

discuss the park’s geologic resources, to address the 

status of geologic mapping by both the Utah Geological 

Survey (UGS) and the United States Geological Survey 

(USGS) for compiling both paper and digital maps, and 

to assess resource management issues and needs. 

Cooperators from the NPS Geologic Resources Division 

(GRD), Natural Resources Information Division 

(NRID), Cedar Breaks NM, UGS, USGS, Southern Utah 

University, Stockton College, USFS and Utah Bureau of 

Land Management (BLM) were present for the two- day 

workshop. 

Day one involved a field trip co- led by SUU geology 

professor Stan Hatfield and USGS geologist Pete Rowley. 

Day two involved a scoping session to present overviews 

of the NPS Inventory and Monitoring (I&M) program, 

the Geologic Resources Division, and the ongoing 

Geologic Resource Evaluation (GRE) for Colorado and 

Utah. Round table discussions involving geologic issues 

for Cedar Breaks NM included interpretation, the UGA 

Millennium 2000 guidebook featuring the geology of 

Utah's National and State parks, the status of cooperative 

geologic mapping efforts, sources of available data, 

geologic hazards, potential future research topics, and 

action items generated from this meeting. Brief 

summaries of each follow. 

Overview of Geologic Resource Evaluation 

After introductions by the participants, Steve Fryer 

(NPS- NRID) presented an overview of the NPS I&M 

Program, the status of the natural resource inventories, 

and the geological resources inventory. 

He also presented a demonstration of some of the main 

features of the digital geologic map for the Black Canyon 

of the Gunnison NM and Curecanti NRA areas in 

Colorado. This has become the prototype for the NPS 

digital geologic map model as it ideally reproduces all 

aspects of a paper map (i.e. it incorporates the map notes, 

cross- sections, legend etc.) with the added benefit of 

being a GIS component. 

It is displayed in ESRI ArcView shape files and features a 

built- in help file system to identify the map units. It can 

also display scanned JPG or GIF images of the geologic 

cross sections supplied with the map. The cross section 

lines (ex. A- A') are subsequently digitized as a shape file 

and are hyperlinked to the scanned images 

For a recap on this process, go to: 

http://www.nature.nps.gov/grd/geology/gri/blca_cure/ 

and view the various files in the directory. 

The geologists at the workshop familiar with GIS 

methods were quite impressed with this method of 

displaying geologic maps digitally; Joe Gregson is to be 

commended for his accomplishments. 

Bruce Heise (NPS- GRD) followed with an overview of 

the Geologic Resources Division and the Geologic 

Resource Evaluation program. 

The GRE also aims to help promote geologic resource 

interpretation within the parks and GRD has staff and 

technology to assist in preparation of useful materials 

including developing site bulletins and resource 

management proposal (RMP) statements appropriate to 

promoting geology. Jim Wood (GRD) and Melanie 

Moreno (USGS- Menlo Park, CA) have worked with 

several other NPS units in developing web- based 

geology interpretation themes, and should be considered 

as a source of assistance should the park desire. 

The UGS has the Geologic Extension Services available 

for help to the NPS for creating interpretive brochures 

and for seasonal employee training. The UGS also has 

programs for applied geology (hazards), economic 

geology, archeology and paleontology. Pete Rowley and 

Stan Hatfield have generously offered their services and 

are also available locally for any assistance the park may 

need regarding geologic issues and interpretation. 

UGA Guidebook on Utah’s National and State Park Areas 

Grant Willis of the UGA announced that a guidebook 

treating the geology of 27 of Utah's national and state 

parks and monuments would be compiled for 

publication in September 2000. This compilation will be 

a snapshot into the geology of each park and covers most 

facets of what the GRE is trying to develop for each park 

for a final report (i.e. cross sections, simplified geologic 

map, general discussions of rocks, structure, unique 

aspects of park geology, classic viewing localities). 

The only NPS unit in Utah that will not be treated will be 

Golden Spike National Historic Site. 

Funding for this publication is coming jointly from the 

UGA, NPS, BLM, USFS and Utah state parks; it is hoped 

that the publication will be sold for under $30. 
34 NPS Geologic Resources Division 

Each author will be encouraged to get with NPS staff 

interpreters to develop a product that aims at a wide 

audience (the common visitor, the technical audience 

and the teaching community). Cedar Breaks NM authors 

will be our field trip leaders (Stan Hatfield, who has also 

tried to enlist the services of Pete Rowley into the 

project). 

Park authors are strongly encouraged to get with NPS 

staff to make sure that any trail logs do follow maintained 

trails and do not take visitors into unauthorized areas, or 

places where resources are fragile and would be 

disturbed by increased visitation (i.e. areas with 

crytptogamic soils). 

Also, a CD- ROM will be distributed with the publication 

featuring road and trail logs for specific parks as well as a 

photo glossary and gallery. The photo glossary will 

describe certain geologic features (i.e. what is 

crossbedding?). These will also be available as webdownloadable Adobe Acrobat PDF files. The UGA 

cannot copyright this material because it is funded with 

state money, so it can be distributed widely and freely, 

which will also benefit the purposes of the GRI. 

Additional reprints are not a problem because of the 

digital nature of the publication and the UGA board is 

committed to additional printings as needed. UGA 

normally prints 1000 copies of their publications because 

they become dated after about five years; that will 

probably not be an issue for this publication. Prices for 

the full- color guidebook are estimated to be 

approximately $25/copy, and sales are expected to be 

high (exact estimates for Capitol Reef NM were 125 

copies/year). A website for the guidebook is forthcoming 

in October 1999. 

Field Trips will be held in September 2000. Currently, 

four field trips are scheduled: 

Arches NP, Canyonlands NP, Dead Horse Point State 

Park (SP) 

Antelope Island SP and Wasatch Mountain SP 

Zion NP, Cedar Breaks NM, Snow Canyon SP and Quail 

Creek SP 

Dinosaur NM, Flaming Gorge NRA, and Red Fleet SP 

Note: Trips 1 and 2 will run concurrently and Trips 3 and 

4 will also run concurrently. 

Many other benefits are anticipated from this publication 

and are enumerated below: 

This type of project could serve as a model for other 

states to follow to bolster tourism and book sales 

promoting their state and its geologic features. 

Sandy Eldredge (UGS) will be targeting teaching 

communities for involvement in the field trips; hopefully 

teachers will pass on what they have learned to their 

young audience. 

The language is intended to appeal to someone with a 

moderate background in geology and yet will be very 

informative to the educated geologist. The publication 

may be able to serve as a textbook to colleges teaching 

Geology of National Parks (in Utah). 

A welcomed by- product could be roadlogs between 

parks in Utah for those visiting multiple parks, perhaps 

with a regional synthesis summarizing how the overall 

picture of Utah geology has developed. 

Paleontological Resources 

Dave Sharrow is interested in having a Paleontological 

Survey conducted for Cedar Breaks National 

Monument. Similar studies have been done at Zion, 

Yellowstone and Death Valley. Vince Santucci (NPSGRD Paleontologist) needs to be contacted for his input 

on this matter. Similar surveys have been done for 

Yellowstone and Death Valley NP's and have shed 

valuable new information on previously unrecognized 

resources. These surveys involve a literature 

review/bibliography and recognition of type specimens, 

species lists, and maps (which are unpublished to protect 

locality information), and also make park specific 

recommendations for protecting and preserving the 

resources. 

The Death Valley Survey will be available soon. The 

Yellowstone Survey is already available on- line: 

http://www.nature.nps.gov/grd/geology/paleo/yell_surve

y/index.htm 

and is also available as a downloadable PDF at 

http://www.nature.nps.gov/grd/geology/paleo/yell.pdf 

If a paleontological survey yields significant findings, 

paleontological resource management plans should be 

produced for Cedar Breaks involving some inventory 

and monitoring to identify human and natural threats to 

these resources. Perhaps someone on the park staff could 

be assigned to coordinate paleontological resource 

management and incorporate any findings or suggestions 

into the parks general management plan (GMP). It would 

be useful to train park staff (including interpreters and 

law enforcement) in resource protection, as the fossil 

trade "black market" has become quite lucrative for 

sellers and often results in illegal collecting from federal 

lands. 

Collections taken from this area that now reside in 

outside repositories should be tracked down for 

inventory purposes. Fossils offer many interpretive 

themes and combine a geology/biology link and should 

be utilized as much as possible in interpretive programs. 

Cooperative Geologic Mapping Efforts for Cedar Breaks 

National Monument 

UGS Perspective 

Currently, the UGS is mapping in Utah at three different 

scales: 1:24,000 for high priority areas (i.e. National and 

State parks), 1:100,000 for the rest of the state, and 

1:500,000 for a compiled state geologic map. 
 CEBR Geologic Resource Evaluation Report 35 

The availability of funding for Cedar Breaks and Zion 

(jointly with the NPS) has made it possible for these 

higher priority areas to be mapped at this detail. The 

UGS plans to complete mapping for the entire state of 

Utah within 10- 15 years at 1:100,000 scale. 

For 1:100,000 scale maps, their goal is to produce both 

paper and digital maps; for 1:24,000 scale maps, the only 

digital products will be from "special interest" areas (i.e. 

areas such as Zion and growing metropolitan St. 

George). Grant Willis mentioned that the UGS simply 

does not have enough manpower and resources to do 

more areas at this scale. He also reiterated that UGS 

mapping goals are coincident with those of the National 

Geologic Mapping Program. 

In Cedar Breaks NM, the UGS has been jointly 

cooperating with the NPS and USGS for some time on 

producing these 1:24,000 quadrangles in both paper and 

digital format. Until 1995, the USGS had done major 

mapping projects under the BARCO (Basin and Range to 

Colorado Plateau transition project) mapping program. 

When the USGS reorganized, many of these projects 

were put on indefinite hold. Fortunately, their has been 

mutual cooperation between the UGS and USGS to work 

together to get these products completed for the NPS. 

The NPS appreciates the labor of all involved parties and 

individuals in this cooperative and hopes that many 

products will result from the combined efforts of all 

involved agencies. 

The UGS has divided their mapping work in the Cedar 

Breaks / Zion areas into two distinct phases. The first 

phase involves producing geologic maps for the 

following quadrangles (see Appendix C, Cedar Breaks 

NM Index of Geologic Maps, 1:24,000 Scale): 

The Guardian Angels (ZION) 

Temple of Sinawava (ZION) 

Clear Creek Mountain (ZION) 

Springdale West (ZION) 

Springdale East (ZION) 

All five quadrangles are field mapped and are presently in 

the internal review stage by the UGS; some field spotchecking is desirable. Some of the mapping was done 

using photogrammetric methods and some is hand 

drawn on Mylar. The UGS expects to deliver both 

completed paper and digital products by October 1, 1999. 

The original projected deliverable date was April 1, 1999; 

however, the UGS has had significant turnover with their 

GIS personnel and has received an extension until 

October 1st

 1999. 

 

The second phase began in spring 1999 and will involve 

geologic mapping for the following quadrangles: 

Kolob Arch (ZION) 

Kolob Reservoir (ZION) 

Cogswell Point (ZION) 

Completion of Smith Mesa (ZION), The Barracks 

(ZION), and Navajo Lake (CEBR) 

The Barracks (southeast of Zion NP) and Navajo Lake 

(south part of Cedar Breaks NM) are already available as 

published Open File paper maps and will be digitized as 

part of this phase. Deliverable dates for this phase should 

be September 2001 according to Grant Willis. 

Some issues have surfaced regarding the correlation of 

Quaternary deposits across quadrangle boundaries, 

which has caused some delay in matching edges between 

maps of the USGS BARCO project and those of the UGS. 

The UGS would like to treat these deposits more indepth. 

USGS Perspective 

Pete Rowley (USGS) talked about the immense scope of 

the BARCO project for preparing 1:100,000 scale maps 

for earthquake potential, mineral resources and various 

other themes. Mapping was done at 1:24,000 scale and 

compiled at 1:100,000 scale. Unfortunately, this project 

was put on the back shelf because of the USGS 1995 

reorganization and many of the original workers have 

not been able to realize final products for their previous 

mapping efforts. 

Since the USGS now requires digital geologic maps for all 

of their work, Pete is working with Southern Utah 

University's (SUU) Dave Maxwell to complete digitizing 

for some of the BARCO work. 

There are many 7.5- minute quadrangles in the BRCA, 

ZION, and CEBR areas that are in various stages of 

completion from USGS personnel; Pete Rowley hopes 

that he will be able to help tidy up some of these 

unfinished maps and make them ready for publication. 

As the park's hydrologist, Dave Sharrow would like to 

see some emphasis on studying the quadrangles east of 

Zion for water issues. These include the Webster Flat 

and Orderville quadrangles. From his perspective those 

closest to the Sevier fault are of most interest to him 

because of a lack of understanding of the hydrology 

nearest the fault. Pete has done a similar type of project 

for Nevada test site and would be willing to further 

discuss this with Dave Sharrow. 

Current Status 

Two 7.5- minute quadrangles cover Cedar Breaks NM: 

Brians Head to the north, and Navajo Lake to the south. 

Flanigan Arch is to the immediate west of Brians Head, 

and Webster Flat is west of Navajo Lake; both are not on 

NPS land. (see figure 11, Cedar Breaks NM Index of 

Geologic Maps, 1:24,000 Scale): 

Navajo Lake is published by the USGS as OF (Open File) 

Report 93- 190 entitled "Preliminary Geologic Map of 

Navajo Lake Quadrangle, Kane and Iron Counties, 

Utah" by David Moore and David Nealey, and was 

published in 1993. Grant Willis thought that the 

Quaternary could use some updating, however. Once 

agreement on the quality of the Quaternary is reached, 

this quadrangle could be digitized at SUU under the 

supervision of Pete Rowley. 
36 NPS Geologic Resources Division 

Existing funding is available to digitize this quadrangle 

under the current agreement between the NPS and UGS 

for Zion and Cedar Breaks. Grant Willis needs to make 

sure that digitization at SUU can be contracted through 

the UGS; he will report back on this. All present thought 

that this was a good idea, as Pete Rowley would be able 

to supervise the work out of SUU, and it would serve as a 

good exercise for SUU, should they receive more of the 

BARCO quadrangles for digitization. 

Brians Head and Flanigan Arch are very near completion 

as Pete Rowley held up drafts of the two quadrangles that 

Ed Sable had been working on. Ed's deteriorating health, 

coupled with the collapse of the BARCO project did not 

allow him to complete these quadrangles. Pete is willing 

to take over these projects and complete deliverables if 

funding can be secured. The NPS may be able to secure 

funding to complete the Brians Head quadrangle, since it 

does fall within the Cedar Breaks boundary. 

It was requested of Tom Henry (CEBR superintendent) 

and Don Falvey (ZION superintendent) that they 

request the services of Pete Rowley from the USGS to 

complete the geologic mapping; GRD can assist with 

writing such a request if they so desire. Pete suggests that 

Sable remain the senior author and Rowley and Hatfield 

as co- authors. Rowley would prepare cross- sections, 

text and do all field checking. 

Other Miscellaneous loose ends: Pete prepared a list of 

other regional quadrangles and categorized them as to 

the status of field mapping and producing paper maps as 

"mostly done", "work still needed", and "USGS 

published quads", as follows: 

Mostly done Work Still 

Needed 

USGS 

Published 

Quadrangles 

Flanigan Arch 

Brian Head 

Red Creek 

Reservoir 

Five Mile Ridge 

Summit 

Kolob 

Reservoir 

Cogswell Point 

Straight Canyon 

Haycock 

Mountain 

Panguitch Lake 

Henrie Knolls 

Navajo Lake 

Cedar City 

Kannarraville 

Cedar 

Mountain 

Parowan 

Paragonah 

Parowan Gap 

Cottonwood 

Mountain 

Little Creek 

Peak 

Hatch 

Asay Bench 

Flanigan Arch and Webster Flat are of interest to CEBR 

and ZION because of the regional watershed, and may 

be able to be treated as "quadrangles of interest" to the 

NPS. Again, much preliminary fieldwork has been on 

these quadrangles by the USGS BARCO team. 

Pete Rowley also mentioned that the USGS has agreed to 

fund the digitization of the Kanab 1:100,000 quadrangle 

through SUU, and hopes to begin overseeing this project 

in the very near future. Kanab greenlines are also 

available. The Panguitch 100,000 quadrangle has also 

been digitized by Florian Maldonado (USGS- Denver) in 

his spare time. 

There are some issues to consider in completing these 

quadrangles: 

Pete would need some financial assistance in digitizing 

these maps at SUU. Dave Maxwell is willing and able to 

get a GIS shop going on BARCO projects as he has 

sufficient equipment and personnel. With Pete's 

oversight and input, it is hoped that many products may 

result from the SUU GIS department. Dave Maxwell 

would also like to get with the UGS for his input on how 

to scope out these digital geology projects. 

An EDMAP project may be a good way to obtain 

assistance for completing any needed field mapping with 

SUU students 

Pete's salary and time needs to be covered by the USGS 

to work on this project. Bruce Heise (NPS- GRD) 

requested a proposal for Pete Rowley's time to complete 

the quadrangles of interest to CEBR and ZION that were 

started under the BARCO project and need some work 

to produce final products. 

It may be possible to tap into the National Mapping 

program to obtain financial assistance here. A two- tier 

proposal was suggested: first just to complete Brian 

Head, and second to include the western quadrangles 

(Flanigan Arch and Webster Flat) with Brian Head. 

Other surficial specialists (Van Williams was mentioned) 

may need to be called upon to help complete the surficial 

mapping and caliche deposits; also numerous landslides 

are known for the area and should be mapped 

appropriately. Salary and time is also an issue for these 

specialists. 

A priority list for quadrangles of interest should be 

developed for SUU and estimates of costs and time to 

complete the work also need to be ascertained. Grant 

Willis suggested that a few weeks for a single quadrangle 

seems like a reasonable amount of time. 

Other Sources of Natural Resources Data for Cedar Breaks 

The UGS has a significant quadrangle database that they 

have furnished to NRID for the entire state of Utah. 

NRID has compiled a geologic bibliography for 

numerous parks and monuments, including Cedar 

Breaks. Visit the website: 

http://165.83.36.151/biblios/geobib.nsf; user id is "geobib 

read", password is "anybody". 

The USGS has compiled large volumes of data on the 

BARCO project that was halted in 1995; much of this 

work is unpublished and should be sought out from 

USGS personnel. 

Dave Sharrow was asked if CEBR currently has their 

ProCite software in place that chronicle any natural 
 CEBR Geologic Resource Evaluation Report 37 

resources into a bibliography. Dave was not sure, and 

thought that Steve Robinson would know for sure. Steve 

needs consulted on this. 

Pete Rowley circulated a few articles by John Anderson 

that are available as UGS publications, and are also 

contained in the geologic bibliography for CEBR. 

Dave Sharrow mentioned that a new water well will be 

drilled on a fault trace near the visitor center observation 

platform; well logs generated from this activity will be of 

interest to GRD, WRD and CEBR. 

Geologic Hazards 

The main geologic hazard discussed for CEBR centers 

around overlooks and fractures within the Claron 

Formation and how safe they are. It was agreed that all 

overlooks should be monitored for fracturing. Tom 

Henry would like some assurances from geologists about 

the stability of the overlooks. Siting facilities is also a 

major issue because of the fractures and potential for 

sloughing; these areas should be monitored for growth 

and potential danger. 

Potential Research Topics Cedar Breaks National 

Monument 

It was mentioned by Tom Henry that the Thomas Bill is 

emphasizing research by local cooperators that provides 

information to management and is applicable to 

interpretation of resources. Integration of this with SUU 

should be taken advantage of. For a quick review of the 

Thomas Bill go to the following website: 

http://rs9.loc.gov/cgibin/bdquery/z?d105:SN01693:|TOM:/bss/d105query.html 

A list of potential research topics includes studies of the 

following: 

• A detailed study of the Claron Formation 

• Study chert distribution around CEBR as it has 

numerous cultural implications as well 

• Develop the fire history from bogs for the last 20,000 

years; Lowder Creek goes back 17,000; Red Valley 

11,000; 3000 for Alpine Pond. 

• Study of the groundwater system; there is lots of 

precipitation and little coming out of the rocks; where 

is it going? CEBR is especially concerned about a 

drinking water supply and enough to flush toilets 

• In relation to the groundwater is a relatively 

unexplored cave and karst system that could use 

additional investigation; surface sinkholes suggest a 

well- developed system that should be studied; consult 

with Ron Kerbo (NPS- GRD Cave Specialist) 

• Look at surface water in relation to forest canopy; 

decreased canopy should increase evapotranspiration 

• Look at discharge rates of surface water 

• Glacial/megabreccia needs investigation around Brian 

Head peak; nothing published by the people Grant 

mentioned (Gary Player) 

• Isom Formation Study 

• Study clustered vegetation and relation to the bedrock 

strata; geologic controls on locations of vegetation 

• Study of rates of erosion and fractures along visitor 

overlooks 

• Any CEBR/BRCA joint research possibilities should be 

lumped (Claron, erosion rates) 

• Catalog unique geologic features; obtain GIS data for 

unique geologic features of CEBR; Dave Maxwell has 

students that are required to do research and he can 

offer their assistance like they are doing at BRCA. SUU 

may become a center of GIS excellence in association 

with Trimble Navigation 

• Consult with John Anderson on any ideas he may have 

for research 

• Attempt to better understand the dune/mud deposits 

on the rim shown by Laird Naylor during the field trip; 

geology and archeology interact here 

• Better understand the role of CEBR in the transition 

between the Basin and Range and Colorado Plateau 

physiographic provinces; develop interpretive display 

at CEBR or Brian Head for this 

Action Items 

Many follow- up items were discussed during the course 

of the scoping session and are reiterated by category for 

quick reference. 

Interpretation 

More graphics and brochures emphasizing the transition 

between the Basin and Range and Colorado Plateau 

targeting the average enthusiast should be developed. If 

Cedar Breaks NP needs assistance with these, please 

consult GRD's Jim Wood (jim_f_wood@nps.gov) or 

Melanie Moreno at the USGS- Menlo Park, CA 

(mmoreno@usgs.gov). 

UGA Guidebook 

Attempt to plant the seeds of this concept to other states 

for similar publications involving local area geology. 

Such publications are especially useful for the GRI 

Paleontological Resources 

Consult with Vince Santucci on the likelihood of a full 

paleontological survey for CEBR 

Geologic Mapping 

Maintain UGS- USGS- NPS cooperation to reap all 

possible products from existing USGS BARCO work to 

benefit the NPS GRI 

USGS address issues relating to funding salaries and 

other work to ensure BARCO products can be published 

USGS develop for SUU a priority list of quadrangles to 

digitize and complete field mapping, as well as associated 

estimates of time and material costs 
38 NPS Geologic Resources Division 

Pete Rowley prepare a 2- tier cost proposal for his 

services to complete geologic field mapping of area 

quadrangles 

Attempt to obtain letters from the CEBR and ZION 

superintendents requesting the services of the USGS to 

complete geologic mapping of quadrangles of interest for 

this region. The UGS has requested similar favors of the 

USGS in the Marysvale area. 

Grant Willis needs to make sure that the Navajo Lake 

quadrangle can be transferred to SUU for digitizing since 

it is part of an existing agreement. 

Natural Resource Data Sources 

Consult with Steve Robinson to see if ProCite database is 

in place for CEBR 

Miscellaneous 

Dave Sharrow would like to receive a "contact list" for 

UGS staff from Grant Willis 

Review proposed research topics for future studies 

within Cedar Breaks NP 

Make contact with USGS GIS person Jeremy Workman 

to develop relationship with NPS GIS projects 

Have conference call with Gregson, Heise, Connors and 

Maxwell to discuss potential future projects, including 

possible digitization of the BRCA maps by Bill Bowers 

(1990) 
 CEBR Geologic Resource Evaluation Report 39 

Scoping Meeting Attendees 

Name Affiliation Phone e- mail 

Bruce Heise NPS, Geologic 

Resources Division (303) 969- 2017 Bruce_Hiese@nps.gov 

Stephanie O’Meara CSU, Research 

Associate (970) 225- 3567 Stephanie_O’Meara@partner.nps.gov 

Tim Connors NPS, Geologic 

Resources Division (303) 969- 2093 Tim_Connors@nps.gov 

Pete Rowley USGS (435) 865- 5928 prowley@usgs.gov 

Grant Willis Utah Geological 

Survey (801) 537- 3355 Nrugs.gwillis@state.ut.us 

Dave Maxwell SUU, GIS (435) 865- 8313 maxwell@suu.edu 

Dave Sharrow NPS- CEBR, 

Hydrologist (435) 586- 9451 Dave_Sharrow@nps.gov 

Steve Robinson NPS- CEBR, Ranger (435) 586- 9451 Steve_Robinson@nps.gov 

Tom Henry NPS- CEBR, 

Superintendent (435) 586- 9451 Tom_Henry@nps.gov 

Stan Hatfield SUU, Geology Dept. (435) 865- 8160 hatfield@suu.edu 

Laird Naylor UT BLM; formerly 

CEBR Archeologist (801) 977- 4357 lnaylor@ut.blm.gov 

Danielle Rousseau NPS, Geologic 

Resources Division (303) 987- 6925 Danielle_Rousseau@nps.gov 

Michael Hozik Richard Stockton 

College of NJ (609) 652- 4277 Hozikm@loki.stockton.edu 

Christy Stauffer USDA FS (435) 865- 3242 Cistauffer@netutah.com 

Bill Case UGS, Extension 

Services (801) 537- 3340 Nrug.bcase@state.ut.us 
40 NPS Geologic Resources Division 

Map coverage of Cedar Breaks National Monument at the scale of 1:24,000. From GRE Scoping Report 
The Department of the Interior protects and manages the nation’s natural resources and cultural heritage; provides scientific and other 

information about those resources; and honors its special responsibilities to American Indians, Alaska Natives, and affiliated Island 

Communities. 

Cedar Breaks National Monument 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2006/006 

NPS D-215, March 2006 

National Park Service 

Director • Fran P. Mainella 

Natural Resource Stewardship and Science 

Associate Director • Michael A. Soukup 

Natural Resource Program Center 

The Natural Resource Program Center (NRPC) is the core of the NPS Natural Resource Stewardship and 

Science Directorate. The Center Director is located in Fort Collins, with staff located principally in 

Lakewood and Fort Collins, Colorado and in Washington, D.C. The NRPC has five divisions: Air 

Resources Division, Biological Resource Management Division, Environmental Quality Division, Geologic 

Resources Division, and Water Resources Division. NRPC also includes three offices: The Office of 

Education and Outreach, the Office of Inventory, Monitoring and Evaluation, and the Office of Natural 

Resource Information Systems. In addition, Natural Resource Web Management and Partnership 

Coordination are cross-cutting disciplines under the Center Director. The multidisciplinary staff of NRPC 

is dedicated to resolving park resource management challenges originating in and outside units of the 

national park system. 

Geologic Resources Division 

Chief • David B. Shaver 

Planning Evaluation and Permits Branch Chief • Carol McCoy 

Credits 

Author • Trista Thornberry-Ehrlich

Editing • Sid Covington 

Digital Map Production • Victor DeWolfe, Stephanie O’Meara, and Dave Maxwell 

Map Layout Design • Melanie Ransmeier
Geologic Resources Division 

Natural Resource Program Center 

P.O. Box 25287 

Denver, CO 80225 

http://www.nature.nps.gov/geology/inventory/ 

(303) 969-2090 

EXPERIENCE YOUR AMERICATM 

National Park Service 

U.S. Department of the Interior