Antietam National Battlefield, 

Chesapeake and Ohio Canal National Historical Park, 

& Harpers Ferry National Historical Park 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2005/006 

National Park Service 

U.S. Department of the Interior 

Natural Resource Program Center 

Antietam National Battlefield, 

Chesapeake and Ohio Canal National Historical Park, 

& Harpers Ferry National Historical Park 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2005/006 

Geologic Resources Division 

Natural Resource Program Center 

P.O. Box 25287 

Denver, Colorado 80225 

January 2005 

U.S. Department of the Interior 

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

and applicability to a broad readership in the National Park Service and to others in the 

management of natural resources, including the scientific community, the public, and the NPS 

conservation and environmental constituencies. Manuscripts are peer-reviewed to ensure that 

the information is scientifically credible, technically accurate, appropriately written for the 

intended audience, and is designed and published in a professional manner. 

Natural Resource Reports are the designated medium for disseminating high priority, current 

natural resource management information with managerial application. The series targets a 

general, diverse audience, and may contain NPS policy considerations or address sensitive 

issues of management applicability. Examples of the diverse array of reports published in this 

series include vital signs monitoring plans; "how to" resource management papers; 

proceedings of resource management workshops or conferences; annual reports of resource 

programs or divisions of the Natural Resource Program Center; resource action plans; fact 

sheets; and regularly-published newsletters. 

Views and conclusions in this report are those of the authors and do not necessarily reflect 

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not constitute endorsement or recommendation for use by the National Park Service. 

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. 2005. Antietam National Battlefield, Chesapeake and Ohio Canal 

National Historical Park, & Harpers Ferry National Historical Park, Geologic Resource 

Evaluation Report. Natural Resource Report NPS/NRPC/GRD/NRR—2005/006. National 

Park Service, Denver, Colorado. 

NPS D-310, January 2005 
 ANTI-CHOH-HAFE 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............................................................................................................. 5

Erosion and Slope Processes.....................................................................................................................................5

Stream Flow, Channel Morphology, and Sediment Load ...........................................................................................6

Historical Landscapes ................................................................................................................................................7

Paleontologic Potential ...............................................................................................................................................8

Water Issues...............................................................................................................................................................8

Wetlands ....................................................................................................................................................................9

Karst Related Issues ..................................................................................................................................................9

General Geology and Ecosystem Concerns.............................................................................................................10

Geologic Features and Processes............................................................................. 15

Antietam National Battlefield ....................................................................................................................................15

Chesapeake & Ohio Canal National Historical Park.................................................................................................15

Harpers Ferry National Historical Park .....................................................................................................................16

Map Unit Properties .................................................................................................... 23

Formation Properties Table ......................................................................................................................................24

Geologic History.......................................................................................................... 27

References Cited......................................................................................................... 31

Appendix A: Geologic Map Graphics ........................................................................ 33

Appendix B: Scoping Summary................................................................................. 36
 NPS Geologic Resources Division iv 

List of Figures 

Figure 1: High water damage at Antietam National Battlefield. ....................................................................................11

Figure 2: Historic structure losing ground to Shenandoah River ..................................................................................12

Figure 3: Slope processes at Harpers Ferry ................................................................................................................13

Figure 4: Slopes along Antietam Creek........................................................................................................................14

Figure 5: High ground at Antietam National Battlefield.................................................................................................18

Figure 6: Low ground at Antietam National Battlefield. ................................................................................................19

Figure 7: Wall rock geology of Chesapeake & Ohio Canal ..........................................................................................20

Figure 8: Lock 30 of the Chesapeake & Ohio Canal ....................................................................................................21

Figure 9: View of Harpers Ferry. ..................................................................................................................................22

Figure 10: Rock units at Harpers Ferry. .......................................................................................................................29

Figure 11: Geologic Time Scale..................................................................................................................................30
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 1

Executive Summary 

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

Geologic Resource Evaluation staff for Antietam National Battlefield, Chesapeake & Ohio 

Canal National Historical Park, and Harpers Ferry National Historical Park in Maryland, 

Virginia, Washington, D.C., and West Virginia. It contains information relevant to resource 

management and scientific research. 

The story of the three parks featured in this report, 

Antietam National Battlefield, Chesapeake & Ohio Canal 

National Historical Park, and Harpers Ferry National 

Historical Park is one of the interaction between man 

and geology. Each park preserves this story in different 

ways. The experience of the parks begins with the 

geology, with the processes that established the 

groundwork from which today’s environments, history, 

and scenery arise. Knowledge of the geologic resources 

should directly impact resource management decisions 

regarding potential geological issues, future scientific 

research projects, interpretive needs, and economic 

resources associated with each of the considered NPS 

units. 

Geologic processes give rise to rock formations, 

mountains and valleys, waterfalls and lakes. These 

processes develop a landscape that welcomes or 

discourages human use. The geology attracted 

indigenous peoples and European settlers to the 

Potomac River valley for hunting, mining, settlement, 

industrial, and agricultural reasons. Geology inspires 

wonder in visitors (some 4,100,780 in 2002) to Antietam, 

Chesapeake & Ohio Canal, and Harpers Ferry, and 

emphasis of geologic resources should be encouraged to 

enhance the visitor’s experience. 

As each park name suggests, historical events within the 

past 200 years are responsible for their existence. This 

history is reflected in the buildings, battlefields, bridges, 

canals, locks, and tow paths found in these parks. Some 

of the principal geologic issues and concerns pertain to 

protecting these historic features. Humans have 

significantly modified the landscape surrounding 

Antietam, Chesapeake & Ohio Canal, and Harpers Ferry, 

and consequently have modified its geologic system. This 

system is dynamic and capable of noticeable change 

within a human life span. Each park is charged with the 

task of preserving a snapshot in human history. 

Geological processes continue to change the landscape, 

making this charge a challenge. 

The following features, issues, and processes were 

identified as having the most geological importance and 

the highest level of management significance to the 

parks: 

• Erosion and Slope Processes. The relatively wet 

climate of the eastern U.S., combined with the steep 

slopes of the Potomac and Shenandoah River valleys, 

and the Antietam Creek basin, creates a setting which 

is especially susceptible to slumping and landslide 

problems. This is due to a lack of stabilizing plant 

growth combined with substantial seasonal runoff and 

frequent occurrence of intense seasonal rainstorms. 

Runoff can dramatically alter the landscape, creating 

new hazard areas in the process. Road and trail 

construction also impacts the stability of a slope. 

Mudstone and shale rich units are typically found in 

outcrop as slopes. These slopes are prone to fail when 

water saturated. Large blocks of jointed and faulted 

sandstone, limestone, and metamorphic rocks are 

more resistant to erosion and form cliffs. Rockfall and 

slope failure are potential hazards almost everywhere a 

cliff face is exposed in the parks. 

• Streamflow, Channel Morphology, and Sediment 

Load. In the wet climate of the eastern U.S., seasonal 

runoff and intense, short duration, seasonal rainstorms 

and subsequent flooding impact channel morphology. 

These seasonal events also result in changes in the load 

and deposition of sediment in the valleys and along 

riverways. These changes affect aquatic and riparian 

ecosystems. Sediment loading can result in changes to 

channel morphology and the frequency of overbank 

flooding. 

• Mining Issues. Intimately tied with the history of 

Chesapeake & Ohio Canal and Harpers Ferry is the 

record of man’s quest to extract useful materials from 

the earth. The history of the town and the canal are 

linked with the transportation of coal and other raw 

materials from the west to the east for use in industry. 

Gold was mined in the area from 1867 through 1940. 

The abandoned shafts from these mines are a 

management concern. The canal itself was built from 

rocks quarried nearby and from the debris left from 

blasting the channels.
 NPS Geologic Resources Division 2 

• Historical Landscapes. The parks were all created to 

preserve a historical context through which the visitor 

may gain insight into the past. Geology played a 

significant role in shaping that history especially 

during the American Civil War. At Antietam National 

Battlefield, among others, the geology influenced the 

battle’s outcome, with highlands and lowlands 

determining strategic advantages for both the Union 

and Confederate armies. 

The geology of the Potomac River valley made canal 

construction necessary to get over the waterfalls and 

rapids associated with the “Fall Line.” Harpers Ferry 

was built on the point of rocks jutting out between the 

Shenandoah and Potomac Rivers. Geology is also 

involved in compromising the manmade structures 

and the preserved historical context. Weathering and 

erosion are relentlessly changing the landscapes of all 

three parks. 

Other geologic parameters and issues such as the 

paleontological potential of the area, water issues, 

wetlands, karst- related issues, and general geological 

and ecosystem concerns, were also identified as critical 

management issues for Antietam National Battlefield, 

Chesapeake & Ohio Canal National Historical Park 

and/or Harpers Ferry National Historical Park. These 

are listed in detail along with recommendations for 

inventories, monitoring, and research on pages 5- 14. 

The rocks present in the Maryland- West VirginiaVirginia area record the ancient beginnings of the 

Appalachian Mountain belt. The Precambrian gneisses, 

schists, migmatites, and intrusive igneous rocks exposed 

in the Blue Ridge physiographic province are more than a 

billion years old. Over the basement of Precambrian 

rocks, sand, mud, and carbonates were deposited during 

the Paleozoic Era. 

The entire region was compressed during three separate 

compressional events, the Taconic, Acadian and 

Alleghanian orogenies. Associated with each orogeny 

was metamorphism and igneous activity. After each 

orogeny, continuing through today, is the processes of 

weathering and erosion. Runoff, rivers, and streams 

transport sediment from the highlands to the Atlantic 

Coastal Plain physiographic province, building the North 

American continent ever eastward. 

Because of the nature of the landscape, several potential 

geological issues need to be considered with regard to 

land- use planning and visitor use in the parks. Along 

with a detailed geologic map and road/trail log, a 

guidebook that would tie Antietam National Battlefield, 

Chesapeake & Ohio Canal National Historical Park, and 

Harpers Ferry National Historical Park to the other 

parks in the National Capital Region could enhance a 

visitor’s appreciation of the geologic history and dynamic 

processes that not only created the landscape but also 

impacted the historical events showcased at each park. 

Strategically placed wayside exhibits could help explain 

the geology to the visitor. 
 ANTI-CHOH-HAFE 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 needed for park 

decision making. The National Park Service (NPS) 

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, operation and maintenance, visitor protection, 

and interpretation. The geologic component is carried 

out by the Geologic Resource Evaluation (GRE) Program 

administered by the NPS Geologic Resource Division. 

The goal of the GRE Program is to provide each of the 

identified 274 “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 non- geoscientists. In preparing products 

the GRE team works closely with park staff and partners 

(e.g., USGS, state geologic surveys, and academics). 

The GRE teams hold scoping meetings at parks to review 

available data on the geology of a particular park and to 

discuss the specific geologic issues in the park. Park staff 

are afforded the opportunity to meet with the experts on 

the geology of their park. Scoping meetings are usually 

held at each park to expedite the process although some 

scoping meetings are multipark meetings for 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 called for in Natural 

Resources Inventory and Monitoring Guideline (NPS75) and the NPS Strategic Plan. 

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

Geologic Setting 

Atlantic Coastal Plain Province: 

The Atlantic Coastal Plain physiographic province is 

primarily flat terrain with elevations ranging from sea 

level to about 60 m (197 ft). The province was formed by 

sediments eroding from the Appalachian Highland areas 

to the west. These sediments were deposited 

intermittently in a wedge- shaped sequence during 

periods of higher sea level over the past 100 million years. 

These deposits were then reworked by fluctuating sea 

levels and the continual erosive action of waves along the 

coastline. The Coastal Plain province stretches from the 

Fall Line east to the Chesapeake Bay and Atlantic Ocean. 

Coastal Plain surface soils are commonly sandy or 

sandy- loams that are well drained. Large streams and 

rivers in the Coastal Plain province including the James, 

York, and Potomac Rivers are often influenced by tidal 

fluctuations. 

Piedmont Plateau Province: 

The “Fall Line” or “Fall Zone” marks a transitional zone 

where the softer, less consolidated sedimentary rock of 

the Coastal Plain to the east, intersects harder, more 

resistant metamorphic rock to the west, forming an area 

of ridges and water falls and rapids. This zone covers 

over 27 km (17 miles) of the Potomac River from Little 

Falls, to Seneca, Maryland. This was the obstacle to 

upriver transportation that the Chesapeake and Ohio 

Canal was constructed to alleviate. Examples of the 

manifestation of this transition can be seen in the 

Potomac Gorge of the Chesapeake and Ohio Canal 

National Historic Park.The Piedmont Plateau 

physiographic province encompasses the Fall Line, 

westward to the Blue Ridge Mountains. (Harris et al., 

1997). 

The Piedmont Plateau was formed through a 

combination of folding, faulting, uplift and erosion. 

These processes resulted in a landscape of eastern gently 

rolling hills starting at 60 m (197 ft) in elevation which 

become gradually steeper moving westwards towards the 

western edge of the province at 300 m (984 ft) above sea 

level. Soils in the Piedmont Plateau are highly weathered 

and generally well drained. 

Blue Ridge Province: 

The Blue Ridge Province is located along the eastern 

edge of the Appalachian Mountains. It contains the 

highest peaks in the Appalachian Mountain system, 

mostly in Great Smoky Mountains National Park. 

Precambrian and Paleozoic igneous and metamorphic 

rocks were uplifted during several orogenic events to 

form the steep terrain. Resistant Cambrian age quartzites 

form Blue Ridge and Short Hill, whereas Precambrian 

metamorphic rocks underlie the valleys (Nickelsen, 

1956). 
 NPS Geologic Resources Division 4 

Eroding streams have caused the narrowing of the 

northern section of the Blue Ridge Mountains into a thin 

band of steep ridges, with elevations of approximately 

1200 m (3937 ft). The Blue Ridge province is mostly 

characterized by steep terrain covered by thin, shallow 

soils, resulting in rapid runoff and low ground water 

recharge rates. 

Valley and Ridge Province: 

The landscape of the Valley and Ridge physiographic 

province is characterized by long, parallel ridges 

separated by valleys. These valleys formed where 

resistant sandstone ridges border carbonate formations. 

The carbonate was more easily eroded, leaving valleys. 

Areas dominated by carbonate formations exhibit karst 

topography. Karst is a term used to describe landscapes 

dotted by sinkholes, caves and caverns. The Shenandoah 

Valley forms the eastern portion of the Valley and Ridge 

province. 

Within the National Capital Region, the following parks 

are all or partially located within the Valley and Ridge 

physiographic province: Antietam National Battlefield, 

Catoctin Mountain Park, Chesapeake and Ohio Canal 

National Historical Park, and Harper's Ferry National 

Historical Park. 

Antietam National Battlefield 

The goal at Antietam National Battlefield is to preserve 

the scene of the single bloodiest day of the American 

Civil War. The Battle of Sharpsburg (as it was known by 

the Confederate Army) began on the morning of 

September 17, 1862 during General Robert E. Lee’s 

campaign to bring war to the northern states. At the end 

of a day of intense fighting, more than 23,110 men were 

dead, wounded, or missing (Antietam National 

Battlefield, General Management Plan, 1991). This battle 

led to Lincoln’s issuance of the Emancipation 

Proclamation. The park is among the best preserved Civil 

War battlefields in the country. Geology played a 

significant role in the battles marking strategic battle 

lines and last stands and remains an important resource 

preservation consideration. 

The 3,255 acre park is located in the heart of Maryland 

surrounded by rolling hills dotted with farms, fields, and 

pastures reminiscent of the day of the battle. It was 

established as a National Battlefield on August 30, 1890. It 

was transferred from the War Department to the 

National Park Service on August 10, 1933. The boundaries 

have changed a number of times since becoming a 

National Park Service unit. The last boundary change 

was November 10, 1978. This was also the date of the 

redesignation of the battlefield. 

Chesapeake and Ohio Canal National Historical Park 

The historic canal stretches along the Potomac River for 

297 km (184.5 miles) of tow path from Washington, D.C. 

to Cumberland, MD. It has more than 400 km (250 miles) 

of boundary making it unique in the National Capital 

Region as the largest and longest. The park’s 19,236 acres 

cut through the four geographic provinces described 

briefly above. It was George Washington’s vision of an 

industrial corridor along the Potomac River that spurred 

the canal’s construction. From beginning of its 

construction in 1828 to the end of all operation in 1924, 

the canal functioned as a transportation route. It was 

primarily used as a corridor for transporting coal from 

western Maryland to the port of Georgetown in 

Washington, D.C. 

In 1938, the Federal government acquired the then 

defunct C&O Canal Company property, focusing on the 

lowermost 37 km (23 miles) of the canal. near 

Washington, D.C., for restoration. With the addition of 

the upper canal, it was established as a National 

Monument on January 18, 1961 by President Eisenhower. 

Then, in 1971, under President Nixon, legislation 

authorized the National Park Service to preserve and 

interpret the park’s historic and scenic features. This 

designated Chesapeake and Ohio Canal as a National 

Historical Park. The boundaries of the park last changed 

on November 10, 1978. 

Hundreds of original structures, including 74 lift locks, 

lock houses, and aqueducts, serve as incredible examples 

of early civil engineering and of the canal's role as a 

transportation system during the so- called Canal Era. 

The canal locks and aqueducts are made of stone 

quarried along the Potomac River Valley and present a 

introduction to the rock types of the Appalachian 

Mountains. The park also supports a great variety of 

recreational opportunities from the highly urbanized 

area in Washington, DC to more the rural communities 

in western Maryland serving 3.1 million visitors in 2000. 

Harpers Ferry National Historical Park 

The small town of Harpers Ferry and the National 

Historical Park associated with it are located at the 

confluence of the Shenandoah and Potomac Rivers in 

the states of West Virginia, Virginia, and Maryland. 

Harpers Ferry played a strategic role in the Civil War 

changing hands 8 times. It was designated a National 

Monument on June 30, 1944, and redesignated on May 

29, 1963, as a National Historical Park. The boundaries of 

Harpers Ferry last changed October 6, 1989. The 2,287-

acre park is within the Blue Ridge physiographic 

province and contains forested mountains, riparian 

habitats, and floodplains that surround the park’s 

historic town area. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 5

Geologic Issues 

A Geologic Resource Evaluation scoping session was held for National Park Service 

Units in the National Capital Region from April 30- May 2, 2001, 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 as they apply to 

Antietam National Battlefield, Chesapeake & Ohio Canal National Historical Park, and 

Harpers Ferry National Historical Park, in particular, those issues that may require 

attention from resource managers are addressed. 

Erosion and Slope Processes 

The topographic relief in the areas around Harpers 

Ferry, Antietam, and along the Chesapeake & Ohio 

Canal can be quite high. In areas such as above Harpers 

Ferry, near Burnside Bridge at Antietam, and near Great 

Falls the likelihood of landslides increases with 

precipitation and undercutting. Using a topographic map 

and a geologic map in conjunction with rainfall 

information could provide some warning for high risk 

areas. 

The intense erosion of steep slopes is responsible for the 

stunning vistas of the Potomac and Shenandoah Rivers. 

However, these erosional processes are also the cause of 

an important geological resource management issue: 

mass wasting and rock falls. 

The walls of many of the river and tributary valleys at 

Antietam, Harpers Ferry, and Chesapeake & Ohio Canal 

are steep slopes (Figures 3 and 4). This renders them 

highly dangerous because of the likelihood of rock falls, 

landslides, slumps, and slope creep. Stronger rock units 

such as sandstones and metamorphic rocks are highly 

fractured creating potential rock fall hazard zones. 

Landslides, slumps, and slope creep are major concerns 

in the weaker rock units such as shales and mudstones. 

Similarly, slumps and other forms of slope failure are 

common for units that are not necessarily associated 

with cliffs. Unconsolidated alluvial deposits for instance, 

are especially vulnerable to failure when exposed on a 

slope. A heavy rainstorm, common in the eastern climate, 

can cause serious damage to valley slopes, many of 

which, due to development lack stabilizing plant and tree 

roots. The rock and soil, suddenly saturated with water, 

can slip down slope causing a huge slump, mudslide, or 

mudflow. 

Many trails in the parks lead visitors through spectacular 

river and forest scenery; however, these trails are at 

extreme risk for rock fall and landslides. In less visited 

areas of the parks, slope processes are also creating an 

impact. 

Flooding of the Potomac and Shenandoah Rivers has a 

profound impact on the riverbanks and the cultural and 

geological resources found there. They are an allencompassing threat to park natural, cultural and 

recreational resources, to park operations and budget for 

extended periods of time. Many structures and trails 

along the Shenandoah at Harpers Ferry are being 

damaged or destroyed by seasonal flooding. 

Erosion and culvert management are major issues, but 

have received little management attention. An inventory 

of the parks’ culverts, many of which are classified 

structures because of the historical character of the 

parks, is needed. An inventory should include the 

impacts of culvert outflows as well as the condition of the 

culverts themselves. 

Inventory, Monitoring, and/or Research Needs 

• Use shallow (10- inch) and deeper core data to monitor 

rates of sediment accumulation and erosion in local 

streams, and analyze changes in chemical constituents 

of sediments. 

• Use repeat LIDAR measurements to document 

changes in shoreline location and elevation along the 

Potomac River. Document changes immediately after 

storms, which generally have impacts that greatly 

exceed continuous processes operating in non- storm 

conditions. 

• Monitor steep slopes for rock movement and manage 

undercut areas appropriately at Harpers Ferry. 

• Study potential relation between shoreline change and 

development, particularly engineering works designed 

to limit erosion. 

• Monitor hazards to staff and visitors from unstable 

slopes and rockfalls. 

• Monitor changes to unstable engineered sites and to 

geologically active areas such as the Potomac Gorge, 

where visitors or park infrastructure such as trails may 

be at risk. 

• Document locations of swelling clays and assess 

impacts to park infrastructure. 

• Monitor erosion rates by establishing key sites for 

repeat profile measurements to document rates of 

erosion or deposition, and reoccupy if possible shortly 
 NPS Geologic Resources Division 6 

after major storm events. Repeat photography may be 

a useful tool. 

• Measure the development of stream deltas as 

surrogates for erosion and sedimentation within an 

entire watershed. 

• Perform a comprehensive study of the erosion and 

weathering processes active at the parks, taking into 

account the different rock formations versus slope 

aspects, location and likelihood of instability. 

• Create a rockfall susceptibility map using rock unit 

versus slope aspect in a GIS; use the map in 

determining future developments, siting of facilities. 

and current resource management including trails, 

buildings, and recreational use areas. 

• Inventory and monitor debris flow potential near 

picnic areas, relate to slope and loose rock deposits. 

• Inventory runoff flood susceptible areas, relate to 

climate and confluence areas. 

• Perform trail stability studies and determine which 

trails are most at risk and in need of further 

stabilization. 

• Further research causes of landslides and slumping to 

help predict future events. 

Stream Flow, Channel Morphology, and Sediment Load 

The rivers and streams greatly define the landscape at 

Antietam National Battlefield, Chesapeake & Ohio Canal 

National Historical Park, and Harpers Ferry National 

Historical Park. Understanding the seasonal variations of 

stream flow and the sediment contained in stream beds is 

necessary to understand the ever evolving ecosystems 

along the waterways. Channel morphology changes, 

especially during flooding, affect cultural as well as 

geological resources by threatening the stability of 

stream banks, creating potential for collapse. Intense 

events may also result in periodic deposits of deep 

sediments. 

Sediment load is an indicator of the level of erosion 

upstream. With development and increasing 

deforestation, sediment load increases continually. 

Sediment loads and distribution affect aquatic and 

riparian ecosystems. Because sediment loading can result 

in changes to channel morphology, overbank flooding 

frequency may also be affected. 

Inventory, Monitoring, and/or Research Needs 

• Correlate changes in stream morphology and sediment 

flux with impacts of external development such as 

removal of vegetation and increases in impervious 

surfaces. 

• Measure long- term and storm- derived changes in 

shorelines, using multispectral aerial photos, lidar, and 

stream gauging. 

• Measure and monitor streamflow, including seasonal 

mean flows, lowest flow rates, and timing and 

magnitude of storm events. With this information, 

develop comparative data between tributaries affected 

by varying degrees of development, and contrast with 

reference streams where watersheds are dominantly or 

entirely within protected land if available. 

• Measure changes in development in park tributary 

watersheds. Incorporate detailed data from 

appropriate county maps into a GIS database, focusing 

on changes in impervious surfaces, road crossings, 

buffering vegetation, and stormwater management 

systems. 

• Measure morphologic change in stream channels. 

Reliable measurements generally require 3- 5 cross 

sections over several hundred meters of channel. 

• Monitor stream flow, including seasonal mean flows, 

lowest flow rates, and timing and magnitude of storm 

events. Supplement data from fixed river- level gauges 

with field data on submergence and exposure of key 

sites that can be correlated with ecosystem response to 

floods and droughts. 

• Determine sedimentation rates and sediment 

composition, including contributions of litter and 

pollution from surrounding developed areas. Establish 

sites for repeat stream profile measurements, and 

obtain measurements shortly after major runoff 

events, if possible. 

• Study the sediment influx for small basins in the parks. 

• Inventory current channel morphological 

characteristics. 

• Conduct hydrologic condition assessment to identify 

actual and potential “problem reaches” for prioritized 

monitoring. Once “problem reaches” are identified, 

monitor with repeat aerial photographs. 

• Research effects of land use and climatic variation on 

streamflow. 

• Investigate paleoflood hydrology. 

• Conduct research of ungaged stream sediment storage 

and load. 

• Measure sediment load on streams of high interest for 

comparative assessment. Data will provide 

information for making management decisions. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 7

Mining Issues 

Abandoned mines pose a serious potential threat to any 

ecosystem. Especially in wet costal environments, surface 

water in steams, surface runoff, and groundwater can be 

contaminated with high concentrations of heavy metals 

leached from mine tailings. Heavy metals may also 

contaminate soils which in turn can impact plant and 

animal life that live on the soil. Abandoned mines are 

hazards for visitors and can alter hydrogeologic test 

results. 

In Chesapeake & Ohio Canal National Historical Park, 

there are four quarries, and three mines. Limestone, 

marble, and the Seneca sandstone were quarried for use 

in constructing the canal before 1828. Gold mining was a 

focus in the Great Falls area from 1867 until about 1940. 

Three closed mining shafts, located near the present 

intersection of Falls Road and MacArthur Boulevard, are 

part of the Maryland Mine. The first shaft, 100 feet deep, 

was sunk in 1867, the second, 135 feet deep was 

completed in 1891, and the last was sunk to 135 feet in 

1906. The Maryland Mine was shut done in 1908 and 

reopened by Atlantic Development Company in 1913 and 

closed again in 1921. There was some development work 

on the 135- foot and 200- foot levels between 1936 and 

1939. The mine closed permanently in 1940 (Goetz, 1979). 

Another mine, the Ford Mine, contains several adits 

which were closed with concrete by the National Park 

Service. Together with the Maryland Mine, they makes 

up the system known as the Great Falls gold mines. The 

Ford Mine collapsed in 1890. The shafts associated with 

the Maryland Mine are plugged and have a fence around 

the backfilled openings (Ingram and Stover 1998). 

Stone material, including gray and red Seneca Sandstone, 

Frederick limestone breccia, Potomac breccia, calico 

marble, and Potomac marble, have been used for many 

national landmarks. These include the Smithsonian 

Castle, the White House and the Capitol building, 

quarried from the Seneca Mill, near Seneca, Maryland, a 

marble quarry from White’s Ferry, Maryland, and the 

marble quarries near Dickerson, Maryland (Ingram and 

Stover, 1998). 

Limestone for cement used in the masonry structures of 

the canal was mined along the Chesapeake & Ohio Canal 

on Round Top Hill, near Hancock, Maryland. The 

Roundtop mine has seven openings (an eighth opening is 

natural) with over 1,400 feet of workings (Goetz, 1979). 

The largest of the seven is 150m (500 ft) deep and with 

stopes 6 to 15 m (20 to 50 ft) high. Three of the openings 

for this mine system lie within the boundaries of 

Chesapeake & Ohio Canal National Historical Park 

(Ingram and Stover 1998). They were closed in with bat 

gates in 1994. The other four are across the rails- to- trails 

hiking/biking path on Maryland state lands. 

The Allegheny Plateau is host to workable bituminous 

coal measures of Maryland, specifically in Allegany and 

Garrett Counties. The southern end of the easternmost 

deposits are in the Upper Potomac basin. The basin is 

drained by the North Branch of the Potomac River. Coal 

mining exposes iron sulfides to oxygen producing 

sulfuric acid. In addition to lowering the pH and 

accelerating the chemical weathering potential of the 

water, Maryland streams downstream of the coal mining 

areas contain elevated levels of dissolved solids, 

including iron, manganese, and aluminum (Hollyday and 

McKenzie, 1973). 

Inventory, Monitoring, and/or Research Needs 

• Conduct periodic water (surface and groundwater) 

and soil sampling and testing to detect and monitor 

heavy metals. Drinking water is especially important 

to monitor. 

• Research the mineralogy and chemistry of ore 

deposits throughout the park including descriptions, 

mineral content, and locations of where the orebearing strata and ore shoots crop out and are 

accessible to the public, and where they may impact 

flora and fauna. 

• Complete inventory of the ore content in the recent 

unconsolidated deposits and soils. 

• For resource management issues and questions, 

contact the Abandoned Mineral Lands (AML) staff 

at the Geologic Resources Division office, Denver, 

CO. 

Historical Landscapes 

The overall goal of the Antietam National Battlefield, 

Chesapeake & Ohio Canal National Historical Park, and 

Harpers Ferry National Historical Park is to maintain the 

landscapes as they were at the time of the specific events 

which led to park formation. Preservation efforts 

encompass both natural and cultural resources. This goal 

is threatened by the continuous natural processes of 

erosion and weathering and the demands of increasing 

local population and urban development (Figures 1 and 

2). Conflicts also arise from opposing values between 

cultural and natural resource management. For example 

a historic leasing program may issue a historic lease to 

provide an avenue for restoration of a historic building 

that may propose removing surrounding natural 

resources or planting exotics. 

Along the Potomac River there are a number of 

overlapping leases, rights- of- way, and easements. The 

Potomac Interceptor sewer line, telecommunications 

lines and towers, utility crossings, power plants, roads 

and highways, railroads, etc. are all competing for space 

and access to the river corridor. 

Inventory, Monitoring, and/or Research Needs 

• Map new development and changing land use, 

including construction, deforestation, other land cover 

changes, and paving of previously vegetated surfaces. 

• Revisit sites of 1950s- 1960s studies of preurbanization streams to assess differences from 
 NPS Geologic Resources Division 8 

present conditions and thus establish initial data points 

to assess rates of change driven by development 

stressors. 

• Create an enhanced topographic map base for 

Antietam National Battlefield. 

• Update resource management for any newly acquired 

lands. 

• Monitor human impacts on camping and climbing 

areas, such as: official and social trails, fishing sites, etc. 

along Chesapeake & Ohio Canal. 

• Use sediment coring, tree ring studies, and historical 

data to develop chronologies of past floods and their 

impacts, then document future frequency and extent 

of flood impacts, including changes to shoreline 

morphology and position, nature of the substrate, 

post- flood changes, and ecosystem recovery. Where 

possible, data should also be collected during storm 

and flood events to monitor immediate effects. 

• Assess the environmental impacts of any proposed 

construction sites near park boundaries via photo 

points or aerial photography. 

• Locate quarries in relationship to locks and other 

stone historic structures along Chesapeake & Ohio 

Canal. 

Paleontologic Potential 

The river and valley landscape at Antietam, Harpers 

Ferry, and Chesapeake & Ohio Canal contains more than 

just a collection of cultural resources and relics, it 

contains a record of prolific ancient life. Fossils at the 

parks record some of the earliest forms of life and 

include several types of Paleozoic and Mesozoic age 

algae, corals, and brachiopods mollusks, and other 

lifeforms. These preserved specimens should be 

protected and catalogued for scientific study, future 

generations, and increased visitor appreciation of the 

parks. 

Inventory, Monitoring, and/or Research Needs 

• Perform a comprehensive study of the paleontologic 

resources at the parks. 

• Compile an inventory of all paleontologic specimens 

present in the parks. 

• Attempt to determine the locations of paleontologic 

specimens removed from the parks that are now in 

private collections to obtain an accurate inventory. 

• Draw visitor attention to the fossil resources at the 

parks with graphics, brochures and exhibits. 

Water Issues 

In the moist eastern climate of Antietam National 

Battlefield, Chesapeake & Ohio Canal National 

Historical Park, and Harpers Ferry National Historical 

Park, water is present in streams, rivers, runoff, springs 

and groundwater wells. Water resources are threatened 

by contamination and overuse in the urban and 

agricultural settings of these park units. The most severe 

threats to park hydrology are presented by existing and 

future development in the rapidly growing region. 

Maintaining an agricultural setting at Antietam creates a 

situation in which runoff from fields both within the 

park and in neighboring farms in the Antietam Creek 

watershed can potentially contaminate both the surface 

water and groundwater systems including springs. 

Knowledge of the chemicals used in regional agriculture 

and an understanding of the hydrogeologic system, 

including groundwater flow patterns are essential to 

protect the park’s ecosystem. In addition to agricultural 

runoff, industrial, sewer, street and commercial runoff 

are also potential sources of water contamination at 

Antietam. 

The movement of nutrients and contaminants through 

the ecosystem can be modeled by monitoring the 

composition of system inputs, such as rainfall, and 

outputs, such as streamflow. Other input sources include 

wind, surface runoff, groundwater transport, mine 

drainage, sewage outfalls, landfills, and fill dirt. The 

parks need to monitor their own water sources for 

discharge and contaminant levels as records from other 

agencies become confused. For instance at the USGS 

gauging station #01619500, downstream of Burnside 

Bridge at Antietam, files indicate several agencies were 

collecting various data at various levels of accuracy and 

clarity. Consistency is crucial to establishing baselines for 

comparison. 

The Potomac and Shenandoah watersheds cover 

enormous areas. Tributaries from a series of small 

watersheds enter the Potomac River along the 

Chesapeake & Ohio Canal. Most of these are ungaged. 

Monitoring water quality and discharge has largely been 

left up to other agencies while the staff at Chesapeake & 

Ohio Canal monitors drinking water wells and 

groundwater contamination sites. 

Streams in effect integrate the surface runoff and 

groundwater flow of their watersheds. In doing so they 

provide a cumulative measure of the status of the 

watershed’s hydrologic system. The park generally 

manages only the last few hundred meters of any 

tributary streams. This means resource management has 

little control over water quality, quantity, or sediment 

load within any tributary streams. Erosion and 

aggradation data for streams in all three parks are scarce. 

Increased interagency cooperation could establish better 

water data controls. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 9

Urban development surrounding the three parks affects 

the watershed in a variety of ways not related to water 

contamination. The hydrogeologic system changes in 

response to increased surface runoff. This increase is a 

result of the further development of impervious surfaces 

such as parking lots, roads and buildings. Sedimentation 

also increases due to land clearing for development. 

Water temperatures increase because of the insulating 

nature of impervious surfaces. Runoff from a parking lot 

on a hot July day is at a much higher temperature than 

from a grassy slope. 

Inventory, Monitoring, and/or Research Needs 

• Monitor ground and surface water quality and 

determine their impacts on the agricultural landscape 

at all three park units (relevant to preserving the 

historic landscape at Antietam National Battlefield). 

• Monitor nitrates, phosphates and herbicides in surface 

water to determine if forests serve as effective buffers 

of contamination at Antietam. 

• Monitor discharge at Mumma and other springs at 

Antietam to establish a baseline. Also determine 

baselines for biological and chemical parameters for 

regional springs. 

• Continue to encourage educational programs such as 

"Water Watchers" (for high schools, started in 1995 at 

Antietam National Battlefield), which collects water 

quality data. 

• Identify point and non- point pollution sources for 

wetlands and tributaries of the Potomac and 

Shenandoah Rivers in the Harpers Ferry vicinity. 

• Develop a monitoring program for water quality with 

an emphasis on protection and restoration projects at 

Harpers Ferry. 

• Obtain digital coverages for existing data on springs, 

map new spring locations for Harpers Ferry National 

Historical Park. 

• Monitor the long- term impacts of flooding on 

resources at Chesapeake & Ohio Canal. 

• Map and quantify subterranean water recharge zones 

at Chesapeake & Ohio Canal. 

• Install monitoring stations to measure atmospheric 

inputs of important chemical components (such as 

nitrogen, mercury, and pH), and outputs to streams 

and groundwater, including karst waters at 

Chesapeake & Ohio Canal National Historical Park. 

• Expand detailed mapping showing changes in 

elevation since the 19th century at Chesapeake & Ohio 

Canal. 

Wetlands 

The dynamic nature of wetland environments makes 

them an indicator of the overall status of the ecosystem. 

Many sites have yet to be identified and/or evaluated. 

The first step toward an inventory would be to validate 

the classification of the Fish and Wildlife Service and 

refine the delineation according to their guidelines. Once 

sites are identified and compared with past photographs 

and records, monitoring trends becomes possible. 

Parameters include water chemistry, sediment influx and 

vascular plant characteristics. 

Inventory, Monitoring, and/or Research Needs 

• Study the effects of fire/drought on wetlands and slope 

stability. 

• Identify and characterize wetland areas at Chesapeake 

& Ohio Canal. Monitor wetlands at Harpers Ferry 

National Historical Park. 

Karst Related Issues 

The rocks present at Antietam, Chesapeake & Ohio 

Canal and Harpers Ferry include limestone, marble and 

other carbonate- rich rocks. Carbonate rocks are 

susceptible to dissolution both from surface water and 

groundwater. Air pollution over the eastern United 

States has caused the acidity of rainwater to increase, 

speeding the dissolution of carbonate rocks. 

Many of the caves along the Potomac River corridor are 

a result of carbonate dissolution. Karst, a term that 

describes the features produced by dissolution of 

carbonate rocks including fissures, sinkholes, 

underground streams, and caverns, is a present concern 

at all three parks. Unknown sinkholes and caverns can 

pose a threat to visitor safety and park infrastructure. 

The presence of a karstic underground passageway can 

profoundly affect the hydrogeologic groundwater 

system. 

Inventory, Monitoring, and/or Research Needs 

• Map surface and subsurface karst features (including 

caves) at Antietam National Battlefield and 

Chesapeake & Ohio Canal National Historical Park. 

• Complete basic cave inventory for Harpers Ferry 

National Historical Park including John Brown Cave. 

• Perform an exhaustive mapping study of specific cave 

areas in the parks to allow for the preservation and 

protection of these resources. 

• Monitor important springs and caves at Harpers Ferry 

for water quality and the presence of rare aquatic 

invertebrates. 
 NPS Geologic Resources Division 10 

General Geology and Ecosystem Concerns 

Inventory, Monitoring, and/or Research Needs 

• Assess geochemical inputs from external sources, 

including wind, surface runoff, groundwater transport, 

mine drainage, sewage outfalls, landfills, and fill dirt 

for impacts on bedrock, soil, and water chemistry. 

• Collect and analyze core samples of soils, sediments, 

and bedrock to assess storage and buffering of 

chemical components (establish a baseline), and 

monitor any chemical changes, including the 

introduction of contaminants. 

• Link to the USGS Minerals Program's geochemical 

landscapes project to provide a regional context for 

the parks. 

• Distribute scientific terminology in layman’s terms to 

park staff for use with public. 

• Develop visitor use maps, publications, guided walks, 

and programs interpreting geology as a significant 

resource in the parks. 

• Correlate geology (surficial and bedrock) with 

vegetation to predict location of plant types, 

distribution, etc.. 

• Identify bedrock of differing geochemical 

characteristics, and correlate with variations in 

assemblages and species richness of ecosystem 

components such as vegetation and aquatic species. 

• Establish monitoring stations at the same sites used for 

vegetation and aquatic monitoring to assess the 

interaction of chemical inputs with ecosystems in 

various geochemical environments, and the varying 

resilience of those environments when subjected to a 

range of chemical stressors. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 11

Figure 1: High water damage at Antietam National Battlefield. Erosion from flooding along Antietam Creek disrupts visitor trail access 

and causes resource management concerns about the protection of Burnside Bridge at Antietam National Battlefield. Photograph by

Trista L. Thornberry-Ehrlich (Colorado State University). 
 NPS Geologic Resources Division 12 

Figure 2: Historic structure losing ground to Shenandoah River. One of many examples of historic structures and features in danger of 

being washed downstream by the Potomac and Shenandoah Rivers at Harpers Ferry National Historical Park. Periodic, seasonal 

floods cause severe river bank damage and change channel morphology. Photograph by Trista L. Thornberry-Ehrlich (Colorado State

University). 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 13

Figure 3: Slope processes at Harpers Ferry. Slope creep and erosional undercutting have undermined this private stairway above 

Harpers Ferry National Historical Park. Such processes have the potential to destroy trails along slopes and bury features below. 

Photograph by Trista L. Thornberry-Ehrlich (Colorado State University). 
 NPS Geologic Resources Division 14 

 

Figure 4: Slopes along Antietam Creek. Periodic floods, and slope processes create trail management issues at Antietam National

Battlefield. Frequent trail closures and maintenance occur due to slumping and high water. Photograph by Trista L. Thornberry-Ehrlich 

(Colorado State University). 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 15

Geologic Features and Processes 

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

and processes in Antietam National Battlefield, Chesapeake & Ohio Canal National 

Historical Park, and Harpers Ferry National Historical Park 

Antietam National Battlefield 

1860 Landscape 

The General Management Plan calls for maintenance of 

the historical landscape at Antietam National Battlefield. 

The landscape present in 1860 included forest, orchard, 

and agricultural fields and farms. Maintaining this 

landscape often means resisting natural geologic 

changes, which presents several management challenges. 

Geologic slope processes such as landsliding, slumping, 

block sliding and slope creep are constantly changing the 

landscape at Antietam. Runoff erodes sediments from 

the open fields and carries them via tributaries to 

Antietam Creek, Sharpsburg Creek and Mumma Run. 

This can impact historical features such as Bloody Lane 

and Burnside Bridge, numerous farmsteads and other 

structures. Erosion naturally diminishes higher areas and 

fills in the lower areas altering the historical context of 

the battlefield (Figures 5 and 6). 

Karst Landscape and Processes 

The carbonate rock units present at Antietam National 

Battlefield include the Chambersburg Limestone, New 

Market Limestone, Pinesburg Station Dolomite, 

Rockdale Run Formation, Stonehenge Limestone, 

Tomstown Formation, among others. The dissolution of 

carbonate rocks by groundwater through fissures, 

cracks, or joints creates karst features. Karst features can 

include underground streams, springs, caves, sinkholes, 

and pinnacles. The karst features around Antietam 

National Battlefield have not yet been inventoried. 

The processes involved in creating a karst landscape 

include dissolution, sinkhole collapse, and the formation 

of caverns. Sinkholes are developed throughout most of 

the formations of carbonate rock in the area but are 

more concentrated in the Elbrook and Conococheague 

formations, Stonehenge Limestone, Rockdale Run 

Formation, and the Chambersburg Limestone. The 

presence of karst has had a dramatic effect on the 

hydrogeology of the area. Since the Antietam Creek basin 

is underlain almost entirely by folded and faulted 

carbonate rocks of lower Paleozoic age, its 

hydrogeologic regime is potentially altered by the 

dissolution of the carbonate below. 

The groundwater discharge of the basin is about 85 

percent of the total. This is higher than surrounding 

areas not underlain by carbonate rocks, but instead by 

Cambrian and Precambrian metamorphic rocks. Large 

quantities of groundwater are stored in the soil and 

substrate. The aquifers in the area are among the most 

productive in the state of Maryland. This groundwater 

comes in large part from streams that flow off the 

mountains directly into sinkholes. Many streams lose 

most of their flow within a mile of reaching the 

carbonate rocks in the valley. The low density of 

perennial streams in the Antietam Creek basin is a result 

of subsurface drainage through solution cavities along 

fractures, faults, joints and sedimentary bedding in the 

carbonate rich rock units (Nutter, 1974). 

Karst landforms, like sinkholes and caves, occur 

elsewhere in the area including in the Great Valley, the 

Valley and Ridge, and the Frederick Valley, Culpeper 

basin, and Westminster terrane in the western Piedmont 

province. These areas have abundant limestone, 

dolomite, and marble rock units (Southworth et al., 

2001). Karst is rare in the Blue Ridge province because 

marble occurs only as small bodies. Karst occurs in three 

different sections of the Piedmont physiographic 

province. Kanawha Spring, just east of Point of Rocks, 

flows from the limestone of the Frederick Formation 

which underlies the flood plain. Limestone cobbles 

within the conglomerate of the Leesburg Member of the 

Balls Bluff Siltstone dissolve forming hummocky 

topography with abundant sinkholes and springs just 

southeast of Point of Rocks. In addition, marble and 

limestone rock units of the Westminster terrane 

(exposed along Monocacy River north of Indian Flats) 

underlie linear valleys. These form abundant sinkholes to 

the north. 

Chesapeake & Ohio Canal National Historical Park 

Canal 

The Chesapeake & Ohio Canal runs along the length of 

the Potomac for some 297 km (184.5 miles) from 

Washington, D.C., to Cumberland Maryland. It was built 

to provide a viable means of transportation over the socalled “Fall Line,” an area of waterfalls along the major 

rivers above the crystalline bedrock of the Piedmont 

physiographic province. Development and westward 

expansion demanded a way to reach the Ohio River 

valley and beyond. Originally the canal was planned to 

extend from Georgetown to Pittsburg, Pennsylvania by 

way of the Potomac, Youghiogheny, and Monogahela 

valleys with a summit tunnel over 6 km (4 miles) long 

(Davies, 1977). 
 NPS Geologic Resources Division 16 

Along the canal’s length are numerous locks, aqueducts, 

lock houses, channels, and tow paths. These historical 

features do more than preserve examples of early civil 

engineering; they present the rock formations and 

geologic structures of the Potomac River corridor in 

miniature. The canal is unique in that it is the only unit 

within the National Park system that crosses 3 

physiographic provinces along a major river. Along its 

entire length the canal provides an opportunity to 

examine the geologic history of the central Appalachian 

region and the canals contribution to development of the 

area (Southworth et al., 2001). 

Sandstones, limestones, dolomites and metamorphic and 

igneous rocks were quarried along the river for the 

construction of the canal. When viewing a large rock 

wall, lining a canal lock, a visitor can see a variety of 

geologic features: fossils, crossbeds, burrows and other 

bioturbation, oolites, gneisses, granites, and soft 

sediment deformation features (Figure 7). In effect, the 

canal itself is a geologic classroom along its length 

(Davies, 1989). 

There are caves along the Chesapeake & Ohio Canal as 

well. Some of these features have emergent springs. The 

canal, running along side the river also provides a 

riparian zone of protection to the Potomac as human 

development increases on the park boundary and on the 

opposite side of river (Figure 8). 

Potomac Gorge 

(Note: The Potomac River itself is not in the park. It falls 

under the jurisdiction of the state of Maryland. The 

Chesapeake & Ohio Canal boundary only goes to the 

high water line on the river banks). 

"Because of its unusual hydrogeology, the Gorge is one 

of the country's most biologically diverse areas, serving 

as a meeting place for northern and southern species, 

midwestern and eastern species, and montane and 

coastal species. The site contains more than 400 

occurrences of 200 rare plant species and communities; a 

major river system with numerous tributaries; 

noteworthy stands of upland forest; many seeps and 

springs harboring rare groundwater fauna; and abundant 

wetlands of various types." (Allen and Flack, 2001). 

The gorge occupies the transition zone between the 

crystalline rocks of the Piedmont physiographic province 

and the sediments of the Atlantic Coastal Plain province. 

During the approximately 5 million years of erosion that 

produced the gorge, the Potomac River has cut at least 6 

different terraces. These are remnants of former flood 

plains and are included in the Quaternary age terrace 

deposits unit. Downcutting into these terraces by the 

Potomac River has created islands, pinnacles, shoestring 

channels, waterfalls, rapids, oxbows, plunge pools, and 

potholes (Southworth, Fingeret, and Weik, 2000). These 

provide a variety of habitats that host the gorge's rich 

ecosystem. 

Periodically large floods, such as in 1936, 1942, 1972, and 

1996, scour the gorge, impact park infrastructure, and 

deposit sediments and massive amounts of debris within 

and along the canal. Floods are major contributors to 

erosion and can dramatically alter the river channel’s 

morphology. This has profound effects on the riparian 

ecosystem present in Chesapeake & Ohio National 

Historical Park including changing the habitat for the 

flora and fauna growing along the river. 

Harpers Ferry National Historical Park 

John Brown Cave 

John Brown is famous at Harpers Ferry for the uprising 

he instigated in 1859, attempting to steal weapons from 

the Federal armory. A cave in the park now bears his 

name. The cave is located near the B&O underpass. This 

cave is approximately 1219 m (4,000 ft) long and formed 

in the carbonate unit of the Tomstown Formation. Here 

the unit is highly deformed as part of the eastern limb of 

a large syncline centered in the overlying Waynesboro 

Formation to the west (Patchen and Avary, 1986). 

1800’s Landscape 

Harpers Ferry was built at the confluence of the Potomac 

and Shenandoah Rivers (Figure 9). During the town’s 

heyday, it was an important intersection of river, 

railroad, and canal transportation routes. A host of 

historical figures including George Washington, Thomas 

Jefferson, Meriwether Lewis, John Brown, Abraham 

Lincoln, “Stonewall” Jackson, Frederick Douglass, and 

George Armstrong Custer all left their mark on the 

history of Harpers Ferry. 

One of the major goals of the park is to preserve the state 

of the town around the time of the Civil War, including 

preserving and restoring the historic buildings in the 

town and the landscape around it. The geology 

encompasses the town itself and is reflected in the 

building stone, carved steps and walkways, and historic 

industries. Hand- carved steps are within the Harpers 

Formation. Robert Harper’s house and St. Johns 

Episcopal Church (1852) were built of Harpers Phyllite. 

Nearby, St. Peters Roman Catholic Church was 

constructed using Weverton Quartzite (Patchen and 

Avary, 1986). Like at Antietam National Battlefield and 

Chesapeake & Ohio Canal National Historical Park, the 

continuous geologic processes of erosion, deposition, 

landsliding, slumping, creeping, rock fall, flooding, and 

chemical weathering present serious challenges to the 

preservation of a snapshot in time. 

Among the rock units underlying the town, forming the 

foundation for many of the town’s structures, and 

forming the precipitous slopes above are the exposed 

shales, phyllites, sandstones, greenstones, dolomites, and 

limestones of the Harpers, Tomstown, Antietam, 

Weverton, Loudoun, Catoctin, and Swift Run 

Formations. Shale predominates on the eastern side of 

the park while limestone is mainly present on the 

western side. Numerous trails run along the sides of the 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 17

hills above the town, showcasing the Paleozoic and 

Precambrian rock units of the Blue Ridge physiographic 

province. 

Blue Ridge Anticlinorium 

The Blue Ridge Anticlinorium is a late Permian age 

structure which underlies the Harpers Ferry area. It 

extends from southern Pennsylvania into Virginia 

(Nickelsen, 1956). The anticlinorium is asymmetrical, the 

western limb is steeper than the eastern limb. It is on the 

western overturned limb of the anticlinorium that the 

excellent exposures of the Harpers Formation, a thick 

sequence of mostly fine- grained metamorphosed clastic 

rocks, show multiple episodes of folding and are 

fundamental in determining the tectonic setting of the 

Alleghanian orogeny. 

The Harpers Formation shows folding, refolded folds, 

and several generations of cleavage. Without these 

features, the urbanization of the area could have taken a 

much different turn. The landforms created by the 

anticlinorium made it necessary to construct canals, 

bridges, and a tunnel. In addition to this, fractures and 

the high degree of dip of the rock beds on the limbs of 

the folds allowed for the development of numerous local 

slate quarries (Patchen and Avary, 1986; Onasch et al., 

1987). 

Wetlands and Riparian Environments 

Approximately 100 acres of wetland area fall within the 

park boundaries. Most of this area is along the banks of 

the Shenandoah River just west of the town of Harpers 

Ferry. Wetlands are an important resource because they 

are particularly susceptible and vulnerable to 

environmental change. Wetlands exhibit rapid responses 

to ecosystem changes and are an excellent indicator of 

the overall health of an ecosystem. They play host to a 

number of bird and plant species of special interest to 

botanists and biologists. 

Harpers Ferry Water Gap 

A water gap is a deep pass in a mountain ridge through 

which a stream or river flows (Harris et al., 1997). The 

water gap at Harpers Ferry is an extreme example due to 

the magnitude of the two rivers joining there. The 

Potomac River has cut its water gap through the Blue 

Ridge Mountains. At places this gap is rather wide. The 

gap through the Blue Ridge- Elk Ridge to the west and 

Short Hill- South Mountain to the east expose the 

repeated beds (due to faulting and folding) of the 

western limb of the Blue Ridge Anticlinorium (described 

above) (Patchen and Avary, 1986). 
 NPS Geologic Resources Division 18 

Figure 5: High ground at Antietam National Battlefield. Strategic high ground areas in the battlefield played a major role in the outcome 

of conflicts during the Civil War. Present resource management concerns include erosion from such highlands in the attempt to 

preserve the historical landscape. Photograph by Trista L. Thornberry-Ehrlich (Colorado State University). 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 19

Figure 6: Low ground at Antietam National Battlefield. “Bloody Lane” was the scene of heavy casualties during the Battle at Antietam; 

another instance of geological-topographical features playing significant roles in history. Photograph by Trista L. Thornberry-Ehrlich 

(Colorado State University). 
 NPS Geologic Resources Division 20 

Figure 7: Rock wall geology of Chesapeake & Ohio Canal, displaying fine examples of the different rock types including limestone, 

dolomite, and sandstone used in the construction of lock 33 of the Chesapeake & Ohio Canal. Photograph by Trista L. ThornberryEhrlich (Colorado State University). 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 21

Figure 8: Lock 30 of the Chesapeake & Ohio Canal. The Potomac River corridor is the site of more than just tourism in the National 

Park units. Many users including the railroad, utility companies, roads and highways, telecommunications lines and towers, tourists, 

local towns and residents all place demands on the resources available along the banks of the Potomac. The park provides a buffer of 

riparian habitat between the river and encroaching development. Photograph by Trista L. Thornberry-Ehrlich (Colorado State 

University). 
 NPS Geologic Resources Division 22 

 

Figure 9: View of Harpers Ferry. Harpers Ferry sits on the slopes above the meeting of the Potomac and Shenandoah Rivers. This 

dynamic setting is inherently subject to flooding, river bank erosion, and channel morphology changes. The steep slopes within and 

above the town are prone to rockfall, slumping and sliding. This presents unique management issues when dealing with the 

preservation of the historic structures of the national historical park. Photograph by Trista L. Thornberry-Ehrlich (Colorado State 

University). 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 23

Map Unit Properties 

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

units that appear on the digital geologic maps of Antietam National Battlefield, 

Chesapeake & Ohio Canal National Historical Park, and Harpers Ferry National 

Historical Park. The table in this section 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 maps or by 

contacting the NPS Geologic Resources Division. 

The Central Appalachian area contains rocks varying in 

age from Quaternary sediments to Precambrian 

metamorphic gneisses. Because of the intense regional 

erosion by the Shenandoah, Potomac, and other large 

rivers and tributaries, these rocks are on striking display, 

indicative of the history of the area. 

The oldest rocks of the area, are Proterozoic gneisses, 

metagranites, marbles, schists, and metarhyolites of the 

Catoctin and Swift Run Formations. The metasediments 

were deposited in an ancient sea basin skirting the 

eastern edge of the newly formed margin of the 

continent with the Iapetus Ocean. The Precambrian 

rocks form the basement upon which all other 

Appalachian rocks were deposited or intruded. 

Early Cambrian Period sediments include the sands, silts, 

limes, and muds of the Mather Gorge Formation, the 

Ijamsville Phyllite, the Loudoun, Laurel, Sykesville, 

Weverton, Harpers, Antietam, Tomstown, Waynesboro, 

Araby, and Frederick Formations. Ordovician age rocks 

include the Conococheague, New Market, 

Chambersburg, and Stonehenge Limestones, the Juniata, 

and Martinsburg Formations, and several intrusive 

igneous units including the Georgetown Intrusive Suite 

and the Bear Island Granodiorite. 

Rock units of Silurian age include the Hampshire, 

Foreknobs, Brallier, Magantango, Oriskany, Needmore, 

Helderberg, Willis Creek, Bloomsburg, Mckenzie and 

Rosehill Formations. Also of Silurian age are the Keyser, 

and Tonoloway Limestones and the Keefer Sandstone. 

The Purslane and Rockwell Formations are 

Mississippian in age. 

Mesozoic age rocks include the Triassic Balls Bluff 

Siltstone and the Manassas Sandstone. Jurassic diabase 

dikes and sills intrude overlying rocks locally. The 

Cretaceous Potomac Formation includes loose 

sediments and abundant plant remains. 

These rocks were uplifted, faulted and folded during 

several orogenies ultimately culminating in the 

Appalachian Mountains. Following each uplift, rapid 

erosion of the areas major rivers and tributaries resulted 

in thick deposits of sediments stretching the coastline 

further east in the Atlantic Coastal Plain physiographic 

province. Quaternary alluvium, colluvium, and terrace 

deposits manifest this erosion- sedimentation process. 

The following three pages present a table view of the 

stratigraphic column and an itemized list of features per 

rock unit. This sheet includes several properties specific 

to each unit present in the stratigraphic column 

including: map symbol, name, description, resistance to 

erosion, suitability for development, hazards, potential 

paleontologic resources, cultural and mineral resources, 

potential karst issues, recreational use potential, and 

global significance. 
 NPS Geologic Resources Division 26 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 27

Geologic History 

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

in Antietam National Battlefield, Chesapeake & Ohio Canal National Historical Park, 

and Harpers Ferry National Historical Park 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 recorded history of the Appalachian Mountains 

begins in the Proterozoic. In the mid- Proterozoic, 

during the Grenville orogeny, a supercontinent had 

formed which included most of the continental crust that 

existed during that time. This included the crust of 

North America and Africa. The sedimentation, 

deformation, plutonism (the intrusion of igneous rocks), 

and volcanism are manifested in the metamorphic 

gneisses in the core of the modern Blue Ridge Mountains 

(Harris et al., 1997). These rocks were deposited over a 

period of a 100 million years and are more than a billion 

years old, making them among the oldest rocks known 

from this region. They form a basement upon which all 

other rocks of the Appalachians were deposited (Figure 

10) (Southworth et al., 2001). 

The late Proterozoic, roughly 600 million years ago, 

brought a tensional, rifting tectonic setting to the area. 

The supercontinent broke up and a sea basin formed that 

eventually became the Iapetus Ocean. This basin 

collected many of the sediments that would eventually 

form the Appalachian Mountains. Some of the sediments 

were deposited as large submarine landslides and 

turbidity flows, and these preserve the dramatic features 

from their emplacement. These early sediments are 

exposed today on Catoctin Mountain, Short Hill- South 

Mountain, and Blue Ridge- Elk Ridge. Also in this 

tensional environment, flood basalts and other igneous 

rocks such as diabase and rhyolite added to the North 

American continent. These igneous rocks were intruded 

through cracks in the granitic gneisses of the Blue Ridge 

core and extruded onto the land surface during the 

break- up of the continental land mass (Southworth et 

al., 2001). 

Associated with the shallow marine setting along the 

eastern continental margin during the Iapetus Ocean’s 

duration, were large deposits of sands, silts, and muds in 

near shore, deltaic, barrier island and tidal flat areas. 

Some of these are represented by the Antietam 

Formation in Central Virginia (Schwab, 1970; Kauffman 

and Frey, 1979; Simpson, 1991). Also, huge masses of 

carbonate rocks represent a grand platform, thickening 

to the east, which persisted during the Cambrian and 

Ordovician Periods (545- 480 Ma). Somewhat later, 540, 

470, and 360 million years ago, amphibolite, granodiorite 

and pegmatite, and lamprophyre, respectively, intruded 

the sedimentary rocks. Several episodes of mountain 

building and continental collision responsible for the 

Appalachian Mountains contributed to the heat and 

pressure that deformed and metamorphosed the entire 

pile of sediments, intrusives, and basalts into schists, 

gneisses, marbles, slates, and migmatites (Southworth et 

al., 2000). 

The rocks were then extensively folded and faulted. This 

may have occurred during regional rifting that occurred 

about 200 million years ago. Given the available fault 

conduits, hot fluids moved upward, depositing quartz 

veins containing small amounts of gold. This was the 

source of the mining interest in the area, intermittently 

from 1867 until 1941 (Reed, Sigafoos, and Fisher, 1980). 

From the Early Cambrian through the Early Ordovician 

time orogenic activity along the eastern margin of the 

continent began again. This involved the closing of the 

ocean, subduction of oceanic crust, the creation of 

volcanic arcs and the uplift of continental crust. In 

response to the overriding plate thrusting westward onto 

the continental margin of North America, the crust 

bowed downwards creating a deep basin that filled with 

mud and sand eroded from the highlands to the east 

(Harris et al., 1997). This so- called Appalachian basin 

was centered on what is now West Virginia. These 

infilling sediments covered the grand carbonate platform 

and are today represented by the shale of the Ordovician 

(450 Ma) Martinsburg Formation (Southworth et al., 

2001). 

During the Late Ordovician, the oceanic sediments of the 

shrinking Iapetus Ocean were thrust westward onto 

other deepwater sediments of the western Piedmont. 

This occurred along the Pleasant Grove fault. 

Sandstones, shales, siltstones, quartzites, and limestones 

were then deposited in the shallow marine to deltaic 

environment of the Appalachian basin. These rocks, now 

metamorphosed, currently underlie the Valley and Ridge 

province. The Piedmont metasediments record the 

transition from non- orogenic, passive margin 

sedimentation to extensive, syn- orogenic clastic 

sedimentation from the southeast during Ordovician 

time (Fisher, 1976). 

Shallow marine to fluvial sedimentation continued for a 

period of about 200 My during the Ordovician, Silurian, 

Devonian, Mississippian, Pennsylvanian, and Permian 

Periods. This resulted in thick piles of sediments. The 

source of these sediments was the highlands that were 

rising to the east during the Taconian orogeny 

(Ordovician), and the Acadian orogeny (Devonian). The 

Taconic orogeny involved a volcanic arc – continent 

convergence. Oceanic crust and the volcanic arc were 
 NPS Geologic Resources Division 28 

thrust onto the eastern edge of the North American 

continent. The Acadian orogeny continued the mountain 

building of the Taconic orogeny as the African continent 

approached North America (Harris et al., 1997). 

Following the Acadian orogenic event, the protoAtlantic Iapetus Ocean was completely destroyed during 

the Late Paleozoic as the North American continent 

collided with the African continent. This formed the 

Appalachian mountain belt. This mountain building 

episode is called the Alleghanian orogeny, the last major 

orogeny of the Appalachian evolution. The rocks were 

deformed by folds and faults to produce the Sugarloaf 

Mountain anticlinorium and the Frederick Valley 

synclinorium in the western Piedmont, and the Blue 

Ridge- South Mountain anticlinorium, and the numerous 

folds of the Valley and Ridge province (Southworth et 

al., 2001). 

During this orogeny, rocks of the Great Valley, Blue 

Ridge, and Piedmont provinces were transported 

westward onto younger rocks of the Valley and Ridge 

along the North Mountain fault. The amount of 

compression was extreme. Estimates of 20- 50 percent 

shortening which translates into 125–350 km (75- 125 

miles) of translation (Harris et al., 1997). Deformed rocks 

in the eastern Piedmont were also folded and faulted and 

existing thrust faults were reactivated as both strike slip 

and thrust faults during the Alleghanian orogenic events 

(Southworth et al., 2001). 

Following the Alleghenian orogeny, during the Late 

Triassic, a period of rifting began as the deformed rocks 

of the joined continents began to break apart from about 

230- 200 Ma. The supercontinent Pangaea was 

segmented into roughly the continents that persist today. 

This episode of rifting or crustal fracturing initiated the 

formation of the current Atlantic Ocean and caused 

many block- fault basins to develop with accompanying 

volcanism (Harris et al., 1997; Southworth et al., 2001). 

Large alluvial fans and streams carried debris shed from 

the uplifted Blue Ridge and Piedmont provinces. These 

were deposited as nonmarine shales and sandstones in 

fault- created troughs such as the Culpeper basin in the 

western Piedmont. 

The large faults which formed the western boundaries of 

the basins provided an escarpment that was quickly 

covered with eroded debris. Igneous rocks intruded into 

the new strata as sub- horizontal sheets, or sills, and 

near- vertical dikes that extend beyond the basins into 

adjacent rocks. After these molten igneous rocks were 

emplaced at approximately 200 Ma, the region 

underwent a period of slow uplift and erosion. The uplift 

was in response to isostatic adjustments within the crust 

which forced the continental crust upwards and exposed 

it to erosion. 

Thick deposits of unconsolidated gravel, sand, and silt 

were shed from the eroding mountains. These were 

deposited at the base of the mountains as alluvial fans 

and spread eastward becoming part of the Atlantic 

Coastal Plain (Duffy and Whittecar, 1991; Whittecar and 

Duffy, 2000; Southworth et al., 2001). The amount of 

material inferred from the now- exposed metamorphic 

rocks is immense. Many of the rocks exposed at the 

surface must have been at least 20 km (~10 miles) below 

the surface prior to regional uplift and erosion. The 

erosion continues today with the Potomac and 

Shenandoah Rivers and tributaries stripping the Coastal 

Plain deposits, lowering the mountains, and depositing 

alluvium on terraces. This fluvial erosion is largely 

responsible for creating the present landscape. 

Since the breakup of Pangaea and the uplift of the 

Appalachian Mountains, the North American plate has 

continued to drift toward the west. The isostatic 

adjustments that uplifted the continent after the 

Alleghenian orogeny continued at a subdued rate 

throughout the Cenozoic Period (Harris et al., 1997). 

The landscape and geomorphology of the Potomac River 

valley in particular is the result of erosion and deposition 

from about the mid- part of the Cenozoic Period to the 

present, or at least the last 5 million years. The 

distribution of flood plain alluvium and ancient fluvial 

terraces of the Potomac River and adjacent tributaries 

record the historical development of the entire drainage 

system. There is little evidence that the river migrated 

laterally across a broad, relatively flat region. It seems the 

river has cut downward overprinting its early course 

(Southworth et al., 2001). 

The position, distribution, thickness, and elevation of 

terraces and the sediments deposited on them along the 

river vary by province and rock type. The elevations of 

terraces along the river show that the slope values of the 

ancient and modern river valley are similar which 

suggests that the terraces formed as the result of either 

eustatic sea level drop or uplift (Zen, 1997a and 1997b). 

Though glaciers never reached the Maryland- West 

Virginia- Virginia area, the colder climates of the ice ages 

may have played a role in the river valley morphology. 

The landforms and deposits are probably late Tertiary to 

Quaternary in age when a wetter climate, sparse 

vegetation, and frozen ground caused increased 

precipitation to run into the ancestral river enhancing 

downcutting and erosion (Zen, 1997a and 1997b).
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 29

Figure 10: Rock units at Harpers Ferry. Greenschist grade metamorphics exposed on a slope near Harpers Ferry National Historical 

Park. Metamorphic rocks are common within the Blue Ridge physiographic province. Photograph by Trista L. Thornberry-Ehrlich 

(Colorado State University). 
 NPS Geologic Resources Division 30 

Figure 11: 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. . 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 31

References Cited 

This section provides a listing of references cited in this report. A more complete geologic 

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

Division. 

Allen, O. and Flack, S., 2001, Potomac Gorge Site 

Conservation Plan; National Park Service and The 

Nature Conservancy (internal use version). 

Burford, A.E., Dean, S.L., 1968, Deep thrusting of the 

Blue Ridge near Harpers Ferry, West Virginia, Special 

Paper - Geological Society of America, p.465- 466. 

Davies, W.E , 1989, Environmental, engineering, and 

urban geology in the United States; Volume 1, New 

York and Washington, D.C.; Highlights of the geology 

and engineering of the Chesapeake and Ohio Canal, in 

Am. Geophys. Union, Washington, DC, United States, 

Hanshaw, P.M., ed. 22 p. 

Davies, W.E., 1971, Historical engineering geology of the 

Chesapeake and Ohio Canal. Geol. Soc. Wash., 10 p. 

Davies, W.E., 1977, Washington to Hancock along the 

Chesapeake and Ohio Canal, in Guidebook for field 

trips in Maryland and the National Capital area, Ridky, 

R.W., ed., Natl. Assoc. Geol. Teachers, East. Sect., 

United States (USA) p.76- 87. 

Duffy, D.F., Whittecar, G.R., 1991, Geomorphic 

development of segmented alluvial fans in the 

Shenandoah Valley, Stuarts Draft, Virginia. Abstracts 

with Programs - Geological Society of America, vol.23, 

no.1, p.24. 

Fichter, L.S, Diecchio, R.J., 1986, Stratigraphic model for 

timing the opening of the proto- Atlantic Ocean in 

northern Virginia. Geology (Boulder), vol.14, no.4, 

p.307- 309. 

Fisher, G.W., 1974, Late Precambrian - early Paleozoic 

rocks of the central Appalachian Piedmont. Geological 

Association of Canada- - Mineralogical Association of 

Canada annual meeting; program abstracts, p. 27- 28 

Fisher, G.W., 1976, The geologic evolution of the 

northeastern Piedmont of the Appalachians. Abstracts 

with Programs - Geological Society of America, vol.8, 

no.2, p.172- 173. 

Goetz, Walter, 1979, Maryland Gold Fever, (published by 

author), 35p. 

Harris, A.G., Tuttle, E., Tuttle, S.D., 1997, Geology of 

National Parks. Kendall/Hunt Publishing Company, 

759 p. 

Ingram, D., Stover, D., 1998, Historic mines of 

Chesapeake and Ohio Canal National Historical Park. 

America's mining heritage, CRM (Washington, D.C.), 

vol.21, no.7, p.17- 18. 

Kauffman, M.E, Frey, E.P. ̧1979, Antietam sandstone 

ridges; exhumed barrier islands or fault- bounded 

blocks? Abstracts with Programs - Geological Society 

of America, vol.11, no.1, p.18. 

Leeper, M.S., Giorgis, S.D., Bailey, C.M., 1997, Structural 

relations in the western Blue Ridge, Nelson & 

Rockbridge counties, Virginia. Abstracts with 

Programs - Geological Society of America, vol.29, 

no.3, p.31. 

Nickelsen, R.P., 1956, Geology of the Blue Ridge near 

Harpers Ferry, West Virginia. Geological Society of 

America Bulletin, vol.67, no.3, p.239- 269. 

Nutter, L.J., 1974, Hydrogeology of Antietam Creek 

Basin. Journal of Research of the U. S. Geological 

Survey, vol.2, no.2, p.249- 252. 

Onasch, C.M., O'Connor, J.V., Levinson, B., 1987, 

Structure and geomorphology of Harpers Ferry. 

Abstracts with Programs - Geological Society of 

America, vol.19, no.1, p.49- 50. 

Patchen, D.G., Avary, K.L., 1986, Harpers Ferry water 

gap. In: Southeastern section of the Geological Society 

of America, Neathery, Thornton L., ed., Geol. Soc. 

Am., Boulder, CO, United States (USA), p. 201- 206. 

Reed, J.C., Jr., Sigafoos, R.S., and Fisher, G.W., 1980, The 

River and the Rocks- The Geologic story of Great Falls 

and the Potomac River Gorge. U.S. Geological Survey 

Bulletin 1471, 75p. 

Reinhardt, J., 1973, Stratigraphy, sedimentology and 

Cambro- Ordovician paleogeography of the Frederick 

Valley, Maryland. 

Schwab, F.L., 1970, Origin of the Antietam Formation 

(late Precambrian?; lower Cambrian), central Virginia. 

Journal of Sedimentary Petrology, vol.40, no.1, p.354-

366. 

Simpson, E.L., 1991, An exhumed Lower Cambrian tidalflat; the Antietam Formation, central Virginia, U.S.A. 

In: Clastic tidal sedimentology, Smith, D G, Zaitlin, 

B.A, Reinson, G.E, Rahmani, R.A., eds. Memoir - 

Canadian Society of Petroleum Geologists, vol.16, 

p.123- 133. 
 NPS Geologic Resources Division 32 

Southworth, S., Brezinski, D.K., 1996, Geology of the 

Harpers Ferry Quadrangle, Virginia, Maryland, and 

West Virginia. U. S. Geological Survey Bulletin, 

Report: B 2123, 33 p., 1 sheet. 

Southworth, S., Fingeret, C., and Weik, T., 2000, 

Geologic Map of the Potomac River Gorge: Great Falls 

Park, Virginia, and Part of the C & O Canal National 

Historical Park, Maryland; USGS Open- File Report 

00- 264. 

Southworth, S., Brezinski, D.K., Orndorff, R.C., Lagueux, 

K.M., Chirico, P.G., 2000, Digital geologic map of the 

Harpers Ferry National Historical Park. U. S. 

Geological Survey, Open- File Report: OF 00- 0297, 1 

disc. 

Southworth, S., Brezinski, D.K., Orndorff, R.C., Chirico, 

P.G., Lagueux, K.M, 2001, Geology of the Chesapeake 

and Ohio Canal National Historical Park and Potomac 

River Corridor, District of Columbia, Maryland, West 

Virginia, and Virginia; A, Geologic map and GIS files 

(disc 1); B, Geologic report and figures (disc 2). U. S. 

Geological Survey, Open- File Report: OF 01- 0188. 

U. S. National Park Service, Antietam National 

Battlefield, Sharpsburg, MD, United States (USA), 1991, 

Antietam National Battlefield, Maryland; Draft 

environmental impact statement and general 

management plan, 89 p. 

Whittecar, G. R., Duffy, D.F., 2000, Geomorphology and 

stratigraphy of late Cenozoic alluvial fans, Augusta 

County, Virginia, U.S.A. In: Regolith in the Central and 

Southern Appalachians, Clark, G.M., Mills, H.H., Kite, 

J.S., eds., Southeastern Geology, vol.39, no.3- 4, p.259-

279. 

Zen, E- an, 1997a, The Seven- Storey River: 

Geomorphology of the Potomac River Channel 

Between Blockhouse Point, Maryland, and 

Georgetown, District of Columbia, With emphasis on 

the Gorge Complex Below Great Falls. U.S. Geological 

Survey Open- File Report 97- 60, 96 p. 

Zen, E- an, 1997b, Channel Geometry and Strath Levels 

of the Potomac River Between Great Falls, Maryland 

and Hampshire, West Virginia. U.S. Geological Survey 

Open- File Report 97- 480, 93 p. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 33

Appendix A: Geologic Map Graphics 

These images provide previews or “snapshots” of the geologic maps for Antietam 

National Battlefield, Chesapeake & Ohio Canal National Historical Park, and Harpers 

Ferry National Historical Park. For detailed digital geologic maps, see included CD. 

The original map digitized by NPS staff to create this product was: Southworth, S., Brezinski, D.K., Orndorff, R.K., Chirico, P.G., and 

Lagueux, K., 2001, Geologic Map of Chesapeake and Ohio Canal National Historical Park and Vicinity, District of Columbia, Virginia, 

Maryland and West Virginia, USGS, OF-01-188A, 1:24,000 scale. For a detailed digital geologic map and cross sections, see included 

CD. 
 NPS Geologic Resources Division 34 

The original map digitized by NPS staff to create this product was: Southworth, Scott; Fingeret, Carrie; Weik, Thomas, 2000, Geologic 

map of the Potomac River gorge: Great Falls Park, Virginia, and part of the C & O Canal National Historical Park, Maryland, U.S. 

Geological Survey, OF-00-264, 1:10000 scale For a detailed digital geologic map and cross sections, see included CD. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 35

The original map digitized by NPS staff to create this product was: Southworth, Scott; Brezinski, D.K.; Orndorff, R.C.; Logueux, K.M.; 

Chirico, P.G., 2000, Digital geologic map of the Harpers Ferry National Historic Park, U.S. Geological Survey, OF-00-297, 1:24000 scale. 

For a detailed digital geologic map and cross sections, see included CD. 
 NPS Geologic Resources Division 36 

Appendix B: Scoping Summary 

The following excerpts are from the GRE scoping meeting held for National Park Service 

Units in the National Capital Region. The scoping meeting occurred from April 30- May 

2, 2001; therefore, the contact information and Web addresses referred to herein may be 

outdated. At the time of this meeting the GRE program was known as the Geologic 

Resources Inventory (GRI). Please contact the Geologic Resources Division for current 

information. 

Executive Summary 

Geologic Resources Inventory (GRI) workshops were 

held for National Park Service (NPS) Units in the 

National Capital Region (NCR) over April 30- May 2, 

2001. The purpose was to view and discuss the park’s 

geologic resources, to address the status of geologic 

mapping 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), individual NPS units in the region, and the 

United States Geological Survey (USGS) were present for 

the workshop. 

This involved half- day field trips to view the geology of 

Catoctin Mountain Park, Harpers Ferry NHP, Prince 

William Forest Park and Great Falls Park, as well as 

another full- day scoping session to present overviews of 

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

GRD, and the on- going GRI. Round table discussions 

involving geologic issues for all parks in the National 

Capital Region included the status of geologic mapping 

efforts, interpretation, paleontologic resources, sources 

of available data, and action items generated from this 

meeting. 

This summary contains a list of attendees for the scoping 

sessions 

This summary also contains notes from C&O Canal staff 

on the meetings 

Included is the PMIS project statement initially proposed 

by Pat Toops and Scott Southworth (note, the funding 

source needs to be updated to reflect the source of 

funding as NPS I&M and not NPS NRPP), see App. G 

Overview of Geologic Resource Evaluation 

The NPS GRE has the following goals: 

• to assemble a bibliography of associated geological 

resources for NPS units with significant natural 

resources (“GRBIB”) to compile and evaluate a list of 

existing geologic maps for each unit, 

• to conduct a scoping session for each park, 

• to develop digital geologic map products, and 

• to complete a geological report that synthesizes much 

of the existing geologic knowledge about each park. 

It is stressed that the emphasis of the inventory is not to 

routinely initiate new geologic mapping projects, but to 

aggregate existing "baseline" information and identify 

where serious geologic data needs and issues exist in the 

National Park System. In cases where map coverage is 

nearly complete (ex. 4 of 5 quadrangles for Park “X”) or 

maps simply do not exist, then funding may be available 

for geologic mapping. 

After introductions by the participants, Tim Connors 

(NPS- GRD) presented overviews of the Geologic 

Resources Division, the NPS I&M Program, the status of 

the natural resource inventories, and the GRE in 

particular. 

He also presented a demonstration of some of the main 

features of the digital geologic database for the Black 

Canyon of the Gunnison NP and Curecanti NRA in 

Colorado. This has become the prototype for the NPS 

digital geologic map model as it reproduces all aspects of 

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

sections, legend etc.) with the added benefit of being 

geospatially referenced. It is displayed in ESRI ArcView 

shape files and features a built- in Microsoft Windows 

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. Geologic cross section 

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

coverage and are hyperlinks to the scanned images. 

Joe Gregson further demonstrated the developing NPS 

Theme Manager for adding GIS coverage’s into projects 

"on- the- fly". With this functional browser, numerous 

NPS themes can be added to an ArcView project with 

relative ease. Such themes might include geology, 

paleontology, hypsography (topographic contours), 

vegetation, soils, etc. 

Pete Chirico (USGS- Reston, VA) demonstrated the 

digital geology of Harpers Ferry and also showed the 

group potential uses of a digital geologic coverage with 

his examples for Anacostia and Cumberland Island. The 

USGS also showed various digital products that they've 

developed already for Chesapeake and Ohio Canal NHP 

and Great Falls. 

At the scoping session, individual Microsoft Word 

Documents of Geologic Bibliographies for each NCR 

park were distributed. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 37

The sources for this compiled information are as follows: 

• AGI (American Geological Institute) GeoRef 

• USGS GeoIndex 

• ProCite information taken from specific park libraries 

These bibliographic compilations were validated by GRE 

staff to eliminate duplicate citations and typographical 

errors, as well as to check for applicability to the specific 

park. After validation, they become part of a Microsoft 

Access database parsed into columns based on park, 

author, year of publication, title, publisher, publication 

number, and a miscellaneous column for notes. 

From the Access database, they are exported as 

Microsoft Word Documents for easier readability, and 

eventually turned into PDF documents. 

Geologic Mapping 

After the bibliographies were assembled, a separate 

search was made for any existing surficial and bedrock 

geologic maps for the National Capital Region parks. 

The bounding coordinates for each map were noted and 

entered into a GIS to assemble an index geologic map. 

Separate coverage’s were developed based on scales 

(1:24,000, 1:100,000, etc.) available for the specific park. 

Numerous geologic maps at varying scales and vintages 

cover the area. Index maps were distributed to each 

workshop participant during the scoping session. 

The index of published geologic maps are a useful 

reference for the NCR. However, some of these maps are 

dated and are in need of refinement and in other places, 

there is no existing large- scale coverage available. The 

USGS began a project to map the Baltimore- Washington 

DC area at 1:100,000 scale and as a result it was brought 

to their attention that modern, large- scale geologic 

mapping for the NCR NPS areas would be beneficial to 

NPS resource management. 

Because of this, the USGS developed a proposal to remap the NCR at large scale (1:24,000 or greater) and to 

supply digital geologic databases to accompany this 

mapping. Scott Southworth (USGS- Reston, VA) is the 

project leader and main contact. The original PMIS 

(Project Management Information Systems) statement is 

available in Appendix C and on the NPS intranet (PMIS 

number 60900); of note is that portions of it need to be 

changed to reflect that the source of funding will be 

Inventory and Monitoring funds and NOT NRPP. 

To better facilitate the geologic mapping, Scott 

Southworth would like to obtain better topographic 

coverage for each of the NCR units. Tammy Stidham 

knows that some of these coverages are already available 

and will supply them to Scott and the USGS. In general, 

anything in Washington DC proper has 1 meter 

topographic coverage and Prince George's county has 

1:24,000 coverage. 

Notes on individual parks within NCR 

• Rock Creek Park (ROCR) has been mapped by the 

USGS at 1:24,000 scale. At the time of the mapping, 

they focused in on the structural geology. Scott would 

like to refine the mapping to 1:12,000 scale, and to 

revisit some of the previous mappers interpretations. 

Tammy Stidham says that a 1:200 topographic base is 

available. Additionally, the USGS would like to obtain 

the topographic contours, hydrography, roads, 

buildings and structures, and digital ortho quarter 

quadrangles for use in a base map. Tammy mentioned 

that soils data is available but that it is dated. 

Digital coverage exists and has been compiled for the 

entire area at 1:100,000 scale. Springs and many historic 

quarries (commodity unknown) are present; there may 

also be paleontological quarries too; USGS has 

historical maps for area; topographic coverage of 1 

meter. 

• George Washington Memorial Parkway (Arlington House)

has immediate resource management issues pertaining 

to the geology of the cemetery, as there are problems 

with stability and sliding at the site, and the sooner a 

geology GIS is created, the more beneficial it is likely 

to be to the park. The park hopes that Scott 

Southworth and USGS scientists will be able to assist 

on this issue. 

• Antietam NB (ANTI) is covered under the existing 

mapping for C & O canal. However, Scott would like 

an enhanced topographic base; Tammy says she can 

supply it. There are also karst issues here, as it relates 

to the hydrology and karst systems here. 

• Catoctin Mountain (CATO) will be a bigger project, as 

there is an interesting surficial geologic story here. 

Base data is needed. Tammy says that at the time of the 

scoping meeting, there is not yet topographic data 

available, but hopefully will be available by the time 

Scott gets there to map. James Voigt is concerned 

about poor forest regeneration and wonders if it’s tied 

to the geology. The park would like to relate 

topographic aspect and the DEMs to the geology as 

well. There were discussions of trying to investigate 

the tie of the purple fringed orchid habitat to 

underlying geology. The superintendent is concerned 

about potential geologic hazards that might be 

associated with climbing, as well as potential problems 

that may exist along Route 77 near Big Hunting Creek. 

Park staff would like to see better interpretive graphics 

pertaining to the geology to use in park brochures as 

well as at wayside exhibits in the park. 

• Chesapeake and Ohio Canal NHP (CHOH) has a digital 

geologic strip map currently under review by the 

USGS; it's hoped that it will be completed by the end 

of this fiscal year (2001). The mapping was done at 

1:24,000 scale, and is in ArcInfo format. It will be 

possible to take the strip map and enlarge the specific 

units of CHOH for ease in resource management. 
 NPS Geologic Resources Division 38 

Also included as part of the CHOH geologic database 

are Antietam NB and most of Monocacy. These can be 

improved if an enhanced topographic base is available. 

Sinkholes are an issue here and it's hoped that the 

geology can be used to predict them; Scott has been 

mapping them as he finds them. Numerous cave 

openings have already been located with GPS units. 

Four gold mines have hazards associated with the 

openings; park should contact the Abandoned Mineral 

Lands (AML) staff in Denver GRD (Dave Steensen or 

John Burghardt). The park is currently working with 

Pete Biggam (GRD Soil Scientist) on their soils maps. 

They have some doqq’s and would like to derive a 

vegetation map from the existing soils and geology 

since they’re so low on the I & M Vegetation priority 

list. They have some color infrared for south area from 

the 1980s that might work. They’d like 1:1200 fly overs, 

but that isn’t something being provided as part of this 

project. Only have a few stereo pairs. They really want 

to integrate and use the data. Scott says Allegheny 

County wants the geologic data to make their soils 

maps. 

Additionally, see the individual synopsis coming from 

Maria Frias and the CHOH Resource Management 

staff below. 

• George Washington Memorial Parkway (GWMP): Melissa 

Kangas and Ann Brazinksi gave us comments during 

our site visit. There are seep issues from Great Falls to 

Key Bridge. Invertebrates are found in these seeps and 

need studied for relationship to geology. Other 

geologic interpretive possibilities include the Historic 

Quarries of soapstone near Key Bridge and the geology 

of Theodore Roosevelt Island. Man- driven shoreline 

changes are also of interest to the park in the tidal area. 

Geologic hazards exist along trails for climbers. There 

is likely a good interpretive story of Theodore 

Roosevelt Island in the seeps on the south parkway in 

coastal plain, some springs, and the James Smith spring 

is of historic interest. They incorporate the fall line 

into the Theodore Roosevelt Island story. The website 

for the digital geology of Great Falls is available at: 

http://geology.er.usgs.gov/eespteam/Greatfalls/INDE

X.HTML 

• Harpers Ferry NHP (HAFE) wants to find uses of their 

digital geologic map. There has been work done on 

rock slides on steep sided slopes from the University of 

West Virginia. Scott Southworth's team has produced 

the digital geology already, and it is available on- line at 

http://geology.er.usgs.gov/eespteam/Harpers/index.ht

m. They used a 5 foot contour to enhance the 

previously published paper map. It is GRD's 

understanding that the map is available in the HAFEGIS and that the park is currently using the data for 

resource management. 

• Manassas (MANA) was unrepresented at the scoping 

session, but Bruce says they’re doing exotic weed 

mapping based on geology. We have high resolution 

topographic data for Prince William County. It’s 

geologically covered in Scott’s 100,000 scale map. 

• Monocacy (MONO) is lumped with Antietam; should 

have topographic coverage soon. Have occasional 

flood problems. 

• National Capital East Parks (NACE); prioritize the parks 

1- 12: 

1. Ft. Washington (gypsum crystals, Paleontology, 

seeps) 

2. Piscataway (significant paleontology, seeps); 

located in Prince George's and Charles Counties 

3. Greenbelt Park 

4. Oxen Run Parkway in DC 

5. Fort Circle Parks in DC with exception of Forts 

Foote, Stanton, Mayhan 

6. Oxen Cove park 

7. Anacostia Kennelworth parks; separate but 

contiguous 

8. BW Parkway 

9. Suitland Parkway 

10. Shepherd Parkway 

11. Harmony Hall 

12. Frederick Douglass Home 

• Prince William Forest (PRWI) has the Quantico 

quadrangle in paper format, however USGS Geologist 

Wright Horton has been out to the park and found 

some issues with miscorrelated volcanic units on the 

map along South Fork (they shouldn't be volcanics). 

There was a major reclamation project of the Cabin 

Branch Pyrite Mine back in 1995 and the rehabilitation 

of the area is continuing still; there are a few websites 

on the subject (EPA website at 

http://www.epa.gov/reg3wapd/nps/pdf/cabinbranch.p

df ; NPS website 

http://www2.nature.nps.gov/grd/distland/prwi_restora

tion. ) The park is preparing "The Geology Trail and 

Related Sites" as an interpretive trail to showcase some 

of the parks geology. There is also an abandoned gold 

mine in the northwest portion of the park with 

partially collapsed mine shafts at Independence Hill. 

Bob Mixon has worked on the geology of the Joplin 

quadrangle; Scott and Pete Chirico will check on the 

status of the open file report as well as bringing Wright 

Horton in on this project. 

• Wolf Trap Farm (WOTR) has 1:24,000 scale topographic 

coverage 

• Other miscellaneous notes of interest: slides associated 

with Fort Circle parks; DC has lots of subsurface data 

from when the Metro was put in; USGS has access to 

it; Metro Rail is tunneled below NPS area and may be 

causing a loss of water to NPS areas from what's 

disappearing below. ROCR, Anacostia and another 

too. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 39

Digital Geologic Map Coverage 

The USGS will supply digital geology in ArcInfo format 

for all of the NCR parks. GRI staff will take this data and 

add the Windows help file and NPS theme manager 

capability to the digital geology and will supply to the 

region to distribute to each park in NCR. 

Other Desired GIS Datasets for NCR 

Soils: Pete Biggam (GRD Soil Scientist) supplied the 

following information in reference to soils for parks: 

National Capitol Parks - Central is covered by the "District 

of Columbia" Soil Survey (State Soil Survey Area ID 

MD099). It has been mapped, and is currently being 

refined to match new imagery. An interim digital product 

is available to us via NRCS, but the "final certified" 

dataset most likely will not be available until FY03. 

National Capitol Parks - Eastern is covered by portions of 3 

soil survey areas; "District of Columbia" (MD099), 

"Charles County, Maryland" (MD017), and "Prince 

George's County, Maryland" (MD033). Both Charles 

County and Prince George's County are currently being 

updated, with Charles County scheduled to be available 

sometime in calendar year 2002, and Prince George's 

County sometime within calendar year 2003. 

Paleontology: Greg McDonald (GRD Paleontologist) 

would like to see an encompassing, systematic 

Paleontological inventory for the NCR describing the 

known resources in all parks with suggestions on how to 

best manage these resources. In addition to the parks 

containing paleo resources in NACE, according to his 

current database, the following are considered "paleo 

parks" in the NCR: 

• Chesapeake & Ohio Canal NHP 

• George Washington Memorial Parkway 

• Manassas NBP 

• Prince William Forest Park 

• Harpers Ferry NHP 

Geologic Report 

A "stand- alone" encompassing report on each parks 

geology is a major focus of the GRI. As part of the USGS 

proposal to map the NCR, they will be summarizing the 

major geologic features of each park in a report to 

accompany their database. It was suggested hoped that 

after the individual reports are finished that a regional 

physiographic report will be completed for the entire 

NCR. 

Timelines 

Appendix C lays out a specific timeline for how the parks 

will progress. 

Also, at this point, Harpers Ferry is complete and now 

Scott's main priority is to complete C & O Canal, then 

perhaps Great Falls (with possible assistance from Barry 

Wood). C & O Canal still needs page size printable maps 

for the individual units though to make it complete. 

For GRFA, Scott already has a write- up for both sides of 

the river ("Geology of the Potomac River Gorge"). 

George Washington Memorial Parkway and Rock Creek 

are also already in progress. 

CHOH staff notes on the scoping session 

“The purpose of the scoping session is to provide an 

informal setting to review the status of existing geology 

projects, discuss how the geology inventory can be used 

by the parks (resource management, interpretation, 

education, etc.). This will also be a great opportunity to 

learn about our geologic resources, locations of hidden 

gold deposits, the inventory process, and to 

communicate special needs or products that could be 

helpful to us (e.g. special maps, etc.).” 

The following is a compilation and thoughts collected 

during the Geology scoping session April 30- May2, 

2001. 

CHOH Interpretation 

Scientific terminology should be distributed to park in 

layman’s terminology of information for use with public 

Needs for the public: develop visitor use maps, 

publications, walks and programs and information for 

development of brochures etc. 

CHOH Natural and Cultural Resource Applications 

Environmental assessments, potential construction sites 

Correlation of Geology (surficial and bedrock) with 

vegetation to predict location of plant types, etc 

Sinkholes: can we find more sinkholes with data? 

Gold mine: What to do with gold mine – Abandoned 

Mines program to be contacted 

VEGETATION MAPPING: 

Park requests development of an interim vegetation map 

product 

Currently have some gross land use data from USGS 1999 

NLCD National Land Cover Dataset (from 30m TM) 

Potential to use 1983- 4 color IR for interim map 
 NPS Geologic Resources Division 40 

NCR collectively addressing vegetation mapping from a 

region wide request : Diane Pavek working with Rapid 

Assessment for Vegetation Mapping (Chris Lea); Mike 

Storey to petition for I&M buy in; I&M funds needed, 1⁄2 

with 1⁄2 NCR Fee Demo. (Tammy Stidham following up 

with Mike Storey) 

Locate quarries in relationship to locks and other stone 

historic structures. 

Erosion issues and flooding of Potomac River – impact 

on resources 

Issues 

Geology project will have mapped specific geologic 

features, such as Devils Eyebrow? 

How to use the data to manage resources: relationships 

among data, application development for park 

Park staff need for instruction and understanding of data 

and appropriate use of data 

Park understands that the strike and dip information was 

not mapped for park – too labor intensive 

CHOH Park Management 

Is large scale mapping possible 1:1200 from Geologic 

mapping program. Answer USGS: no 

Goal: determining relationships between our resources 

Workshop: NCR or select like parks – develop a 

workshop for interpretation with geologists and liaison 

go between and resources management to promote use 

of information for public at park. 

What can WASO do for the park? 

Potomac Gorge geology review: currently assessing 

geology of Potomac gorge and Mather Gorge – tie into 

POGO SCP Site Conservation Plan possible??? 

WASO GRD

Plan to have Geology Scoping Report completed by 

mid- May 

Role is NPS75 I&M goal to inventory geologic resources 

No funding for interpretation or interpretive products 

2 WASO positions as liaisons between Interpretation, 

science and resources management 

Developing GIS applications and Theme manager, one 

application per each of 12 GIS theme layer; GEO data to 

be prepared for park and installed into theme manager 

3 year proposal with USGS: National Geologic Mapping 

Project Goals 

Title: Geologic Mapping – minimum data sets: NCR 

parks 1:24,000 

NCRO- N- 002.000 

Scoping sessions with parks 

Develop park specific bibliography: known references of 

park from PROCITE, USGS Geo- Index and AGI 

(American Geologic Institute) Geo- reference 

Produce through USGS digital geologic map (delivered 

in Theme Manager format) 

Prepare geologic reports per park and for the region 

NCR? 11 parks mapped 

Large scale 1:6000 

Tailored to park products 

Time frame: USGS plans to complete mapping for 

CHOH by end of FY01 

NPS training: data management training with theme 

applications: Soils, vegetation, geology, H2O, etc 

Current option for technical assistance: Contact Lindsey, 

Eastern Representative at USGS to broker and obtain 

technical assistance from USGS for what ever, including 

interpretation 

Technical Assistance request can be made to the NRPC 

(?) for application development; not an NRPP request; to 

I&M program 

Funding requests through the unified call 

Geo- Scientists in the parks: GRD administers for in the 

park seasonal geo- scientist for projects such as 

developing interpretive products; contact in GRD is ? 

Shortly after the scoping sessions, our office releases a 

"scoping summary" posted to a website as both 

documents and web pages. Some examples from Utah 

can be found at: 

http://www2.nature.nps.gov/grd/geology/gri/products/s

cope_summary/ 

USGS 

Parks requested from USGS 50 copies for NCR parks 

Circular 1148, Forum on Geologic Mapping Applications in 

the Washington-Baltimore Urban Area 

USGS interested in getting the information to the public 

but will rely on NPS to do this kind of work; not in 

current scope of work in above mentioned project. 
 ANTI-CHOH-HAFE Geologic Resource Evaluation Report 41

USGS requests CHOH to GPS map perimeter of sink 

holes in park 

USGS requests CAVE openings data from CHOH 

National Geologic Mapping Project, led by Scott 

Southworth; products in GIS with a tabular usable 

database which will be reviewed by GRD 

Anacostia project – historic and current hypsography 

mapped and compared; too cool. 

Potomac Gorge geology review: currently assessing 

geology of Potomac gorge and Mather Gorge – tie into 

POGO SCP Site Conservation Plan possible??? 

Interpretation Vs Data: 

USGS will provide the facts in understandable 

terminology plus data attributes. NPS to interpret data 

Solicit Park and History Association to adopt and 

publish ‘Rocks and the River’ and other new publications 
 NPS Geologic Resources Division 42 

List of Scoping Meeting attendees with contact information 

NAME AFFILIATION PHONE E- MAIL 

Joe Gregson NPS, Natural Resources 

Information Division (970) 225- 3559 Joe_Gregson@nps.gov 

Tim Connors NPS, Geologic 

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

Bruce Heise NPS, Geologic 

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

Lindsay 

McClelland 

NPS, Geologic 

Resources Division 202- 208- 4958 Lindsay_mcclelland@nps.gov 

Scott 

Southworth USGS (703) 648- 6385 Ssouthwo@usgs.gov 

Pete Chirico USGS 703- 648- 6950 Pchirico@usgs.gov 

Pat Toops NPS, NCR 202- 342- 1443, 

ext. 212 Pat_toops@nps.gov 

James Voigt NPS, CATO 301- 416- 0536 Cato_resource_management@nps.gov 

Marcus 

Koenen NPS, NCR 202- 342- 1443, 

ext. 216 Marcus_koenen@nps.gov 

Ellen Gray NPS, NCR 202- 342- 1443, 

ext. 223 Ellen_gray@nps.gov 

Dale Nisbet NPS, HAFE 304- 535- 6770 Dale_nisbet@nps.gov 

Suzy Alberts NPS, CHOH 301- 714- 2211 Susan_alberts@nps.gov 

Dianne 

Ingram NPS, CHOH 301- 714- 2225 Dianne_ingram@nps.gov 

Bill Spinrad NPS, CHOH 301- 714- 2221 William_spinrad@nps.gov 

Debbie 

Cohen NPS, ANTI 301- 432- 2243 Debbie_cohen@nps.gov 

Ed 

Wenschhof NPS, ANTI/MONO 301- 432- 2243 Ed_wenschhof@nps.gov 

Ann 

Brazinski NPS, GWMP 703- 289- 2541 Ann_brazinski@nps.gov 

Melissa 

Kangas NPS, GWMP 703- 289- 2542 Melissa_Kangas@nps.gov 

Barbara 

Perdew NPS, GWMP 703- 285- 2964 Barbara_Perdew@nps.gov 

Barry Wood NPS, GWMP 703- 289- 2543 Barry_wood@nps.gov 

Marie Sauter NPS, CHOH 301- 714- 2224 Marie_frias@nps.gov 

Carol Pollio NPS, PRWI 703- 221- 2176 Carol_pollio@nps.gov 

Duane 

DonnellyMorrison 

NPSl, PRWI 703- 221- 6921 Duane_donnelly- morrison@nps.gov 

Diane Pavek NPS- NRS 202- 342- 1443, 

ext. 209 Diane_Pavek@nps.gov 

Chris Jones NPS- WOTR 703- 255- 1822 Christopher_Jones@nps.gov 

Doug Curtis NPS- NCR- NRS 202- 342- 1443, 

ext.228 Doug_Curtis@nps.gov 

Brent Steury NPS- NACE 202- 690- 5167 Brent_Steury@nps.gov 

Dave Russ USGS 703- 648- 6660 Druss@usgs.gov 

Tammy 

Stidham NPS- RTSC 202- 619- 7474 Tammy_stidham@nps.gov 

Dan Sealy NPS- GWMP 703- 289- 2531 Dan_Sealy@nps.gov 

Sue Salmons NPS- ROCR 202- 426- 6834, 

ext. 33 Sue_salmons@nps.gov 
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. 

Antietam National Battlefield, Chesapeake and Ohio Canal National 

Historical Park, & Harpers Ferry National Historical Park 

Geologic Resource Evaluation Report 

Natural Resource Report NPS/NRPC/GRD/NRR—2005/006 

NPS D-310, January 2005 

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 and Bruce Heise 

Digital Map Production • Victor DeWolfe and Stephanie O’Meara 

Map Layout Design • Melanie Ransmeirer
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