GEOLOGY

VOL. 34, NO. 1

CONTENTS

Getting rid of carbon dioxide .................................................................... 1Coal-bed methane—energy within reach ................................................. 2New releases ........................................................................................... 10

Earthquake catalog and epicenter map................................................ 10Brandy Camp digital coal-resource maps and datasets ....................... 12Hydrogeologic and well-construction characteristics of the rocks of

Pennsylvania.................................................................................... 14Interview—Author of new mystery book combines art and Pennsylvania

geology ................................................................................................ 16Book review—Earth Colors by Sarah Andrews ........................................ 18Earth science teachers’ corner................................................................. 20

ON THE COVER

Examples of the Bureau’s publications in the new digital format. Left toright: Map 69, Water Resource Report 69, and Mineral Resource Report99 (see articles on pages 10–16) (photograph by Clifford H. Dodge).

PENNSYLVANIA GEOLOGY

PENNSYLVANIA GEOLOGY is published quarterly by the Bureau of Topographic andGeologic Survey, Pennsylvania Department of Conservation and Natural Resources,3240 Schoolhouse Road, Middletown, PA 17057–3534.Editor: Anne B. Lutz.Contributed articles are welcome. Guidelines for manuscript preparation may be obtainedat www.dcnr.state.pa.us/topogeo/pub/pageolmag/pageolguide.aspx or by contacting theeditor at the address listed above.

VOL. 34, NO. 1 SPRING 2004

DEPARTMENT OF CONSERVATION AND NATURAL RESOURCESBUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEY

IN COOPERATION WITH THE U.S. GEOLOGICAL SURVEYTOPOGRAPHIC MAPPING

GROUNDWATER-RESOURCE MAPPING

Main Headquarters3240 Schoolhouse RoadMiddletown, PA 17057–3534717–702–2017FAX: 717–702–2065

Pittsburgh Office500 Waterfront DrivePittsburgh, PA 15222–4745412–442–4235FAX: 412–442–4298

BUREAU STAFF AND TELEPHONE NUMBERSDirector and State GeologistJay B. Parrish, P.G. 717–702–2053

Assistant DirectorSamuel W. Berkheiser,

Jr., P.G. 717–702–2055

Administrative ServicesLynn M. Goodling 717–702–2054Elizabeth C. Lyon 717–702–2063

Library ServicesRichard C. Keen 717–702–2020Lewis L. Butts, Jr. 717–702–2018

Publication ServicesJody R. Zipperer

(General Inquiries) 717–702–2073Christine E. Miles, P.G. 717–702–2044Caron E. O’Neil, P.G. 717–702–2042Anne B. Lutz 717–702–2043

Local Government Outreach ServicesKristen L. Reinertsen

(East) 717–702–2047Jaime Kostelnik (West) 412–442–5828

Database ServicesCheryl L. Cozart 412–442–4234Janice Hayden 412–442–4287Joseph E. Kunz 412–442–4235Lynn J. Levino 412–442–4299Karen L. McCoy (Oil and

Gas GIS Services) 412–442–5826

GIS ServicesMichael E. Moore, P.G. 717–702–2024John H. Barnes, P.G. 717–702–2025Thomas G. Whitfield, P.G. 717–702–2023

GIS Services (continued)Stuart O. Reese, P.G. 717–702–2028Thomas K. Yeager, P.G. 717–702–2026

Water Well ServicesSharon E. Fesus 717–702–2074Jody R. Zipperer 717–702–2073

Groundwater ServicesGary M. Fleeger, P.G. 717–702–2045Thomas A. McElroy, P.G. 717–702–2046

Geologic Mapping ServicesJon D. Inners, P.G. 717–702–2034Gale C. Blackmer 717–702–2032Helen L. Delano, P.G. 717–702–2031Clifford H. Dodge, P.G. 717–702–2036William E. Kochanov, P.G. 717–702–2033James R. Shaulis, P.G. 717–702–2037Viktoras W. Skema, P.G. 717–702–2035

Laboratory and Geochemical ServicesRobert C. Smith, II, P.G. 717–702–2021Leslie T. Chubb 717–702–2022

Coal-Bed Methane ServicesAntonette K. Markowski,

P.G. 717–702–2038

Coal Quality and Availability ServicesRodger T. Faill, P.G. 717–702–2041Leonard J. Lentz, P.G. 717–702–2040John C. Neubaum 717–702–2039

Oil, Gas, and Subsurface GeologicalServicesJohn A. Harper, P.G. 412–442–4230Christopher D. Laughrey 412–442–4232Joseph R. Tedeski 412–442–4295Kristin M. Carter, P.G. 412–442–4233

COMMONWEALTH OF PENNSYLVANIAEdward G. Rendell, Governor

DEPARTMENT OF CONSERVATION AND NATURAL RESOURCESMichael DiBerardinis, Secretary

OFFICE OF CONSERVATION AND ENGINEERING SERVICESRichard G. Sprenkle, Deputy Secretary

BUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEYJay B. Parrish, Director

Bureau web site: www.dcnr.state.pa.us/topogeoDCNR web site: www.dcnr.state.pa.us

Pennsylvania home page: www.state.pa.us

STATE GEOLOGIST’S EDITORIAL

Getting Rid of Carbon Dioxide

In this issue, you will read about coal-bed methane, a hot topicin Pennsylvania because it is a potential source of clean energy. An-other hot topic is how to remove excess carbon dioxide from the at-mosphere. Carbon is released as a waste product during combustionand combines with oxygen to form CO2. Excess CO2 in the atmos-phere may contribute to global climate change; therefore, we have a vested interest in reducing the amount of carbon products in theatmosphere. There are several methods that can accomplish thiscarbon sequestration. Trees can be planted on land and planktongrowth can be encouraged in the oceans, tying up carbon in organicmatter; solid carbonate forms can be created; or CO2 can be lockedup in geologic units. CO2 can be pumped into a coal seam that con-tains methane, pushing the methane to a collecting well where it canbe harvested for clean-burning energy. In this case, everyone wins:the CO2 pollution is removed from the atmosphere and is tied up ina coal seam, and a fuel is brought to the surface more efficiently.

The Pittsburgh office of our bureau, led by John Harper, hasteamed with seven other states and Battelle Laboratories to examinegeological sinks (storing carbon in subsurface rock formations) as partof a study of carbon sequestration in the Appalachian, Illinois, andMichigan basins funded by the Department of Energy. Several avenuesof approach are being considered in this multimillion dollar study, includ-

ing pumping CO2 into oil and gas reservoirs,deep unminable coal seams, abandonedunderground coal mines, and saline (brine)aquifers. The results of the study will beavailable to CO2-generating industries as asophisticated geographic information systemthat can show prospective geological sinkswithin reasonable distances of these indus-tries. Look for an article on this topic in anupcoming issue of Pennsylvania Geology.

Jay B. ParrishState Geologist

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WHY COAL-BED METHANE? “National demand for natural gas is in-creasing, with the resource now heating 50 percent of U.S. homesand fueling 95 percent of new power plants” (Pinsker, 2002, p. 34).By 2020, the demand for natural gas in this country is forecast to in-crease by 53 percent (Holtberg and others, 2000). During the 1990s,United States production capacity did not keep pace with demand.This large domestic shortfall was met by Canadian natural gas im-ports (American Gas Association, 2000). Another way to reduce gasdeficits would be to fully develop known domestic reservoir basinsand explore for untapped sources of natural gas, one of which iscoal-bed methane (CBM). CBM (also called coal-seam natural gas)is one of the fastest growing energy plays in North America today.

CBM is an energy source that rivals conventional natural gas incomposition and heating value. Historically a mining hazard, CBM isnow extracted in many areas both to improve mine safety and foruse as a valuable part of the energy mix. It is also produced fromabandoned mines and from coals too thin or too deep to justify min-ing. Many people in the early 1980s were skeptical that CBM wouldprove to be useful, equating it to pursuing a quixotic dream. Coal,likewise, has been viewed as a vestige of the industrial revolution in-stead of being an active partner in the “methane economy” that nowbridges the transition from a carbon-fuel economy to one that is car-bon free. The latest coal-reserve estimates of 32 billion tons, 78 per-cent of which is bituminous coal and 22 percent of which is anthracitecoal, ensure that Pennsylvanians will have reliable, low-cost energyfor decades to come (Pennsylvania Coal Association, 2000).

Time, improved technology, and better understanding of thecoal reservoir have shown CBM to be credible, economic, and moreenvironmentally friendly than the mining or combustion of coal. CBMis commonly introduced into natural gas pipelines for domestic, com-mercial, and industrial fuel. Other uses are as a boiler fuel in gas tur-

Coal-Bed Methane—Energy Within Reach

by Antonette K. MarkowskiBureau of Topographic and Geologic Survey

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bines to generate electricity at cogeneration plants (power plantsthat simultaneously generate electrical energy and low-grade heatfrom the same fuel); as chemical feedstock for methanol, ammonia,and other chemicals; as raw material for the production of liquefiednatural gas and gas products; and in cofiring, in which natural gasand coal are burned together to use coals that are marginally com-pliant with clean-air laws.

UNIQUE RESOURCE. In today’s consumer-driven society, alternativesources of energy and fuel are highly desirable and are being seri-ously considered for environmental and business concerns. Amongthese are CBM, coal, oil shales, tar sands, gas hydrates, geothermalresources—and perhaps more familiar—renewable solar energy, windfarms, and hybrid vehicles. Considered to be an “unconventional”natural gas, CBM can be used in the same way as natural gas fromconventional reservoirs such as sandstone and shale. CBM is notassociated with “conventional” geological trapping mechanisms suchas faults or impermeable rocks because the gas is mainly attachedto the molecular structure of the coal. The large and complex inter-nal surface area of coal provides a very efficient storage system thatcan contain up to seven times as much gas as an equal rock volumeof a conventional gas reservoir (Rice, 1997). CBM is a unique re-source because it is both generated and stored within the coal-bedreservoir. More information on methane generation, composition, andreservoir characteristics can be found in Markowski (1993, 2001).

NATIONAL OVERVIEW. A conservative estimate for the CBM resourcein the conterminous United States is more than 700 trillion cubic feet(Tcf) (1 billion cubic feet of methane could heat 14,494 householdsfor 1 year), of which 100 Tcf are recoverable, enough to provide a 5-year supply at present rates of consumption (Nuccio, 2000). CBMaccounts for about 10 percent of our total domestic natural gas pro-duction. Development of this resource has been expanding in mostcoal basins in the United States. According to the Petroleum Tech-nology Transfer Council (1999), the Rocky Mountain states take cen-ter stage in CBM production in the following coal basins: the SanJuan in Colorado and New Mexico, yielding 918 billion cubic feet (Bcf)in 1997; the Powder River in Wyoming and Montana, currently exhibit-ing dramatic growth; the Uinta in Utah; and the Raton in Coloradoand New Mexico. Colorado’s Piceance basin is also a western player.In the east, Alabama’s Black Warrior basin was a major CBM producerin the early 1990s, the Central Appalachian basin in Virginia and West

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Virginia continues to gain momentum, and the Northern Appalachianbasin, mainly in Ohio, Pennsylvania, and West Virginia, is also show-ing promise with a recoverable resource estimate of 11.5 Tcf (Rootand others, 1996). The recoverable resource estimate for Pennsyl-vania is 2.7 Tcf, 2.3 Tcf from bituminous coal beds and 0.4 Tcf fromanthracite coal beds (Geomega, Inc., 1983). Frontier areas havingpotential include the following coal basins: Wind River, Green River,and Hanna-Carbon in Wyoming; Illinois; Texas Gulf Coast; westernCanada sedimentary basin in Alberta and British Columbia; and theTyonek play at Cook Inlet north of Anchorage, Alaska (Lyle, 2000).

SUMMARY OF ACTIVITY AND TRENDS IN PENNSYLVANIA CBMRECOVERY. About 485 permits documented since 1938 reflect wellsexhibiting serendipitous discoveries of gas from coal, unsuccessfulattempts at extracting CBM, and various degrees of CBM produc-tion. Briggs and Tatlock (1999) noted that coal-seam natural gas pro-duction in a few localities began in the 1890s.

According to available information from known well operators, aconservative estimate of 250 CBM wells are in commercial produc-tion in southwestern Pennsylvania (see back cover), most of whichare operated by Belden and Blake Corporation and CONSOL Energy,Inc. This is almost nine times as many wells as the number reportedin 1997. About 139 of these wells are commingled-gas CBM wells(wells that extract methane from multiple coal seams in a verticalborehole) in Fayette, Indiana, and Westmoreland Counties at a totalproduction of 3,550 thousand cubic feet per day (Mcfd) (John Miller,personal communication, 2004). Hydraulic stimulation (the creation ofnew fractures by high-pressure injection of sand, water, and addi-tives) is used to enhance production of low-permeability reservoirs.

The well total also includes an estimated 93 gob-gas CBM wellsfrom active and abandoned mines in Cambria, Greene, and Wash-ington Counties at a total production of 3,740 Mcfd. Gob gas is the gasthat comes from the fractured zone of coal and surrounding strataabove the coal that has collapsed during longwall mining; the heat-ing value of gob gas ranges from 300 to 800 British thermal units percubic foot (Btu/cf).

Among the producing wells are seven horizontal wells in unminedcoal in Greene County at a total production of 1,060 Mcfd. Produc-tion from one of the seven horizontal wells is 400 Mcfd (Joe Aman,personal communication, 2004). Horizontal drilling (a type of direc-tional drilling), commonly used in the oil and gas industry, starts with

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a vertical well bore, and at a selected point of deviation, drilling iscontinued horizontally to enter the target reservoir. The current prac-tice is to drill about 3,000 feet into the coal seam. CNX Gas Company,LLC, a subsidiary of CONSOL Energy, Inc., is using horizontal welltechnology to maximize reservoir surface area and gas drainage whileminimizing industry’s “footprint” on the landscape. Five vertical CBMwells in Greene County are fed by about 30 horizontal wells at 800Mcfd. Plans for a new horizontal-well project in Washington Countyare under way.

Until about 1993, the amount of CBM produced in Pennsylvaniawas almost negligible. Although production levels varied during thenext six years, there was a dramatic rise in 1999, followed by con-tinued growth. For 2002, production increased to 1.7 Bcf (Figure 1) ata spot market contract price (current one-time purchase price fornext-day delivery) of about $10 million/million British thermal units(MMBtu) of CBM. This is equivalent to heating about 25,000 house-holds in a year. Indiana County has the largest reported productionat 950 million cubic feet (MMcf) (Figure 2) from the Campbells Millpool, Blairsville field, worth $5 million/MMBtu of CBM.

TO

TAL

GA

S (

Mcf

)

YEAR

1,400,000

1,200,000

1,000,000

800,000

600,000

400,000

200,000

01988

1,600,000

1,800,000

1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Figure 1. Reported annual coal-bed methane production in thousand cubic feetin southwestern Pennsylvania from 1988 to 2002. Amounts for years 1988 through1992 are 1988, 1,824 Mcf; 1989, 6,027 Mcf; 1990, 0 Mcf; 1991, 1,335 Mcf;and 1992, 559 Mcf.

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CBM production in Pennsylvania occurs in coal-bearing rocksfrom the base of the Monongahela Group down to the base of thePottsville Formation at depths generally ranging from 300 to 2,000 feet(Figure 3). Despite the hurdle of determining ownership of the gas ifownership rights have not been clearly established, interest in devel-oping this resource continues to grow. Contributing to this interestare improved technology, better understanding of coal as a naturalgas reservoir, higher gas prices, and the need to develop domesticenergy sources to compensate for the inevitable depletion of pres-ently known oil and gas reserves in this century.

Additional information on the regional geology; cross sections ofcoal-bearing rocks; isopach, isopleth, and isolith maps of coal andassociated sandstone units; and other related maps can be found inBruner and others (1995); well data is contained in Markowski (2000).Gas-content data can be found in a reconnaissance study of Penn-sylvania CBM resources (Markowski, 2001).

ENVIRONMENTAL PROBLEMS BECOME ECONOMIC OPPORTUNI-TIES. As part of Pennsylvania Energy Harvest, a $5 million programto encourage clean and renewable energy projects, the Pennsylva-nia Department of Environmental Protection (DEP) recently issued anair-quality plan for a new methane-recovery project in Franklin, Wayne,and Whiteley Townships, Greene County (Pennsylvania Departmentof Environmental Protection, 2003). RAG Emerald Resources, LP, and

TO

TAL

GA

S (

Mcf

)

COUNTY

700,000

600,000

500,000

400,000

300,000

200,000

100,000

0CAMBRIA FAYETTE GREENE INDIANA WASH-

INGTONWEST-MORE-LAND

800,000

900,000

1,000,000

Figure 2. Reported annual coal-bed methane production (in thousand cubicfeet) for 2002 in Cambria, Fayette, Greene, Indiana, Washington, and West-moreland Counties.

RAG Cumberland Resources, LP, affiliates of RAG American CoalCompany, will participate by allowing a portion of their coal-mine gasesto be captured and used as an alternative energy source. This inno-vative project includes a methane collection system and a gas pro-cessing plant. Up to 6 electric and 16 gas-fired, engine-driven com-pressors will be placed at mine boreholes to flush methane from themine and out to the processing facility by pipeline. Processing willremove water and other impurites, upgrading the gas to commercialquality, or pipeline quality. Pipeline-quality gas standards are typically97 percent methane and a heating value of approximately 1,000 Btu/cf.The plant is capable of treating 5.75 MMcf of raw CBM per day (equiva-lent to 4.95 MMcf of pipeline-quality methane gas). According to theDEP, this will eliminate 600,000 tons of methane emissions each yearand help turn a formerly vented gas into a usable energy source.

PROPOSED PARTNERSHIPS. Two CBM projects, one that may befunded by the federal government and industry, and the second by

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Figure 3. Generalized stratigraphic column showing target coal beds of south-western Pennsylvania.

SYS- SER- GROUP OR TARGETTEM IES FORMATION COAL BEDS

PE

NN

SY

LV

AN

IAN

MID

DLE

UP

PE

R

SewickleyPittsburgh

Upper BakerstownLower Bakerstown

Mahoning

Upper FreeportLower FreeportUpper KittanningMiddle KittanningLower KittanningClarion/Brookville

Upper MercerLower Mercer

MonongahelaGroup

ConemaughGroup

AlleghenyFormation

PottsvilleFormation?

MIS

-S

IS-

SIP

-P

IAN

LOW

-E

R

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state government, have been proposed to the Pennsylvania Geologi-cal Survey. The first research project, initiated by the U.S. Geologi-cal Survey (USGS), would involve CBM exploration drilling and ground-water evaluation (which is also important to the design of a gas-de-velopment field) in the CBM frontier of the Anthracite region of east-ern Pennsylvania. State and federal scientists would cooperate tocollect anthracite coal samples for analysis of their CBM content,gas composition, and coal-gas and carbon dioxide storage capacities.Recent research by Lyons and others (2003) indicated that Pennsyl-vania anthracite coal beds have a very high capacity to hold methaneunder pressure, with values ranging from about 320 to 850 cubic feetper ton (cf/t). CBM values from the National Institute for OccupationalSafety and Health (formerly the U.S. Bureau of Mines) have a range offrom 6 to 691 cf/t of anthracite from depths of 1,359 feet and 685 feetrespectively, 691 cf/t being one of the highest measured gas contentsrecorded nationwide (Diamond and others, 1986). Selected bedswould be candidates for relative porosity and permeability determina-tions. Other parameters to be evaluated include the geochemistry ofwaters that are produced with methane, the capacity of the anthracitefor carbon dioxide sequestration (the storage of carbon dioxide toreduce the amount in the atmosphere), and the capacity of carbondioxide to be used to enhance CBM production. Support is beingsought for this two-year project from industry and from the USGS Di-rector’s Venture Capital Fund. The USGS Venture Capital Fund is anational competitive funding program whose aim is to support collabo-ration among scientists from two or more USGS disciplines for inte-grated scientific/technical efforts that are high risk, high reward, andthat can significantly impact the nation (U.S. Geological Survey, 2004).Partnerships outside the USGS are encouraged, but not required.

The second CBM project, a partnership with DEP, would resultin a series of investigative drillholes in the Northern Anthracite field.New CBM data for the Anthracite region would be obtained from thedrillholes, along with information that would enhance geologic map-ping efforts in the northeastern part of Pennsylvania.

REFERENCESAmerican Gas Association, 2000, 1999 gas facts: Washington, D.C., p. 1–12.Briggs, R. P., and Tatlock, D. B., 1999, Petroleum—guide to undiscovered recoverable

natural gas resources, chap. 38C of Shultz, C. H., ed., The geology of Pennsylva-nia: Pennsylvania Geological Survey, 4th ser., Special Publication 1, p. 531–547.[Co-published with the Pittsburgh Geological Society.]

Bruner, K. R., Oldham, A. V., Repine, T. E., Jr., and others, 1995, Geological as-pects of coalbed methane in the Northern Appalachian coal basin, southwesternPennsylvania and north-central West Virginia [Topical Report, August 1990 to Au-gust 1993]: Chicago, Ill., Gas Research Institute, GRI Contracts 5091–214–2261and 5087–214–1544, 72 p.

Diamond, W. P., LaScola, J. C., and Hyman, D. M., 1986, Results of direct-methoddetermination of the gas content of U.S. coalbeds: U.S. Bureau of Mines Informa-tion Circular 9067, 95 p.

Geomega, Inc. [Briggs, R. P., and Tatlock, D. B.], 1983, Estimates of undiscoveredrecoverable natural gas resources in Pennsylvania: unpublished report, 35 p.

Holtberg, P. D., Lihn, M. L., Nice, K. D., and Cochener, J. C., 2000, Baseline projec-tion data book—2000 edition of the GRI baseline projection of U.S. energy supplyand demand to 2015: Chicago, Ill., Gas Research Institute, Volume II, GRI ReportGRI–00/0002.2, 246 p.

Lyle, Don, 2000, Coalbed methane fuels growth: Houston, Tex., Hart’s E&P, v. 73,issue 10, p. 17–18.

Lyons, P. C., Bustin, R. M., and Markowski, A. K., 2003, Coalbed methane potential(CBM–P) in Main Bituminous field (SW. PA) and the Anthracite fields (E. PA), andCBM–P in MD, VA, MA, RI (U.S.A.): Program and Abstracts for the 20th AnnualMeeting of The Society for Organic Petrology, p. 72–73.

Markowski, A. K., 1993, Coal-bed methane—new energy from an old scourge?: Penn-sylvania Geology, v. 24, no. 2, p. 8–14.

________ 2000, Pennsylvania coal-bed methane wells spreadsheet: PennsylvaniaGeological Survey, 4th ser., Open-File Report 00–01.

________ 2001, Reconnaissance of the coal-bed methane resources in Pennsylva-nia: Pennsylvania Geological Survey, 4th ser., Mineral Resource Report 95, 134 p.

Nuccio, Vito, 2000, Coal-bed methane—potential and concerns: U.S. Geological Sur-vey Fact Sheet FS 123–00, http://pubs.usgs.gov/factsheet/fs123-00/ (accessed May2004).

Pennsylvania Coal Association, 2000, Pennsylvania coal data 2000: PennsylvaniaCoal Association, 36 p.

Pennsylvania Department of Environmental Protection, 2003, DEP issues air qualityplan approval for methane recovery project: http://www.dep.state.pa.us/newsletter/default.asp?NewsletterArticleID=1237&SubjectID= (accessed May 2004).

Petroleum Technology Transfer Council, 1999, New technology summary: http://www.pttc.org/tech_sum/ts_154.htm (accessed May 2004).

Pinsker, L. M., 2002, Coalbed methane—the future of U.S. natural gas?: Geotimes,v. 47, no. 11, p. 34–35.

Rice, D. D., 1997, Coalbed methane—an untapped energy resource and an environ-mental concern: U.S. Geological Survey Fact Sheet FS 019–97, http://energy.usgs.gov/factsheets/Coalbed/coalmeth.html (accessed May 2004).

Root, D. H., Attanasi, E. D., Mast, R. F., and Gautier, D. L., 1996, Estimates of in-ferred reserves for the 1995 USGS National Oil and Gas Resource Assessment:U.S. Geological Survey OF 95–0075–L, 29 p.

U.S. Geological Survey, 2004, Fiscal Year 2004 U.S. Geological Survey BureauVenture Capital Fund Research Call for Proposals Procedures: U.S. GeologicalSurvey Collaborative and Innovative Research Opportunity, 6 p.

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NEW RELEASES

Earthquake Catalog andEpicenter Map

Earthquakes do occur in Penn-sylvania, albeit not as frequentlyas in California. Every two yearsor so, a noteworthy earthquakeoccurs somewhere in the com-monwealth. The most recent onehappened on November 4, 2003,southeast of Reading.

The Bureau of Topographic andGeologic Survey has releasedMap 69, Earthquake Catalog andEpicenter Map of Pennsylva-nia, a catalog and a map of 420natural seismic events (earth-quakes) in and near Pennsylva-nia, and 17 human-related events,compiled by staff geologistRodger T. Faill. This is a com-plete listing of events from theearliest recorded, in 1724, to July31, 2003. Newspaper reports arethe primary original source of in-formation for most of the earth-quakes up until the mid-1960s.Since then, seismic instrumentshave provided more accuratedata, especially for time of occur-rence, location, and magnitudeof the event. The information foreach event, where available, in-cludes date and time, location (bylatitude and longitude as well asgeographically), magnitude, in-tensity, depth of focus, and thesources of information.

The epicenter map for Pennsyl-vania and its immediately surround-ing areas (an approximately 35-mile-wide apron) shows the geo-graphic distribution of the earth-quake activity. The distribution isnot even. By far, most of the earth-quakes have occurred in two zonesin the southeastern part of thecommonwealth. The first passesthrough Philadelphia and southernBucks County as part of a zoneextending from Wilmington, Del.,to New York City. The other areaof concentration is the Lancasterseismic zone, a northeast-south-west-trending belt centered onLancaster and stretching from theSusquehanna River to Reading.

The northwestern corner ofPennsylvania has also been seis-mically active. The events are inthe eastern part of an active areaaround the city of Ashtabula innortheastern Ohio. Indeed, thestrongest earthquake ever re-corded in Pennsylvania, a mag-nitude 5.1 event near Lake Py-matuning in mid-October 1998,was part of this group.

The rest of the state is seismi-cally quite inactive. The occa-sional events (once per decade orso) are widely scattered. Events in-duced by human activity (quarry

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blasts and mine collapses, forexample) are distinguished fromnatural events in this catalog. Per-haps the most prominent artificialoccurrences were the coal-minecollapses in the Wilkes-Barre areain 1954, which were considerednatural events for quite some time.

The earthquake catalog re-sides in a Microsoft Access data-base. It is accompanied by meta-data in a Portable Document For-mat (PDF) file, which contains adescription of the structure (fields)of the database, the data therein,and their sources. The data areprovided in dBASE IV format aswell. A PDF version of the cata-log in tabular form can also beprinted as hard copy.

The epicenter map of Pennsyl-vania, which includes a text and listof earthquakes by map number, ispresented at a scale of 1:750,000as a PDF file. The map is 52 by32 inches in size when printed.The epicenter map, cropped to in-clude only the map area and ex-planation, is also available as ageoreferenced image (GeoTIFF).The earthquake epicenters areprovided as a dataset in an ArcGISshapefile, and as an ArcInfo (ver-sion 8.2) export file. A metadatafile accompanies the export file.

The references to sourcescited in the database are listed ina PDF file, and are also availableas an export from the Accessdatabase in dBASE IV format.

A portion of the epicenter map of Pennsylvania, showing epicenters in the Lan-caster seismic zone. The multicolored 1:750,000-scale map is shown here ingrayscale at approximately 1:1,071,430.

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The Bureau of Topographicand Geologic Survey announcesthe release of Mineral ResourceReport 99, Bedrock GeologicMap, Coal-Resource Maps, andDigital Datasets of the BrandyCamp Quadrangle, Elk, Jeffer-son, and Clearfield Counties,Pennsylvania, by staff geologistClifford H. Dodge. This all-digitalpublication, available on CD–ROM, is an outgrowth of several

popular Mineral Resource Reportsby the Bureau that contain setsof county coal-resource maps ata scale of approximately 1:62,500.The growing need for more rapidpublication and dissemination ofgeologic maps at a scale of1:24,000 and demand for geologicinformation in digital form have ledto this new publication format,which will replace the hard-copy,page-sized county reports.

Brandy Camp Digital Coal-Resource Maps and Datasets

A portion of a coal-resource map (1:24,000 scale) from the Brandy Camp re-port, showing crop lines, adits, and mined-out areas on the Lower Kittanningcoal. The multiple colors of the original map cannot be shown in this image.

Map 69 is available on CD–ROM from the State Bookstore atthe address given at the end ofthe announcement of Water Re-source Report 69 for $5.00 plus

shipping fees and sales tax asnoted. It can also be purchasedover-the-counter at the Bureau’sMiddletown office (see addresson back cover).

MainBituminouscoal field

Brandy Campquadrangle

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The Brandy Camp report pro-vides information on the arealbedrock geology (Upper Devo-nian to Pennsylvanian), structure,coal resources, and extent of pastsurface and underground coal min-ing for an important area in theMain Bituminous coal field not pre-viously studied in detail. It con-tains both graphic images (mostlymaps) that can be printed on de-mand by the user from PDF filesand digital datasets (coverages)prepared using ESRI ArcInfo soft-ware, which can be employed forspatial analysis and other geo-graphic-information-systems (GIS)applications and for preparationof customized hard-copy maps.The digital datasets were usedto create the maps. A brief text isincluded as well.

The 13 graphic images (plates)include a colored geologic mapand two kinds of coal-resourcemaps at a scale of 1:24,000. Thecolored geologic map shows thedistribution of the bedrock forma-tions, structure contours and foldaxes (axial-plane traces), and lo-cations of selected data points,including drill holes, field stations,gas wells, and water wells. In-cluded on the map plate are acorrelation diagram and descrip-tion of map units, a representa-tive columnar section of the coalmeasures (also provided as astand-alone illustration), and ap-propriate collar information (infor-mation printed on the borders thatsurround the map image).

The coal-resource maps in-clude: (1) a composite map, show-ing outcrops (crop lines) of all thecoals identified, structure con-tours, and fold axes, and (2) sepa-rate maps for each principal (com-mercial) coal bed, showing thecrop line (where coal is present),horizon line (projected or inferredoutcrop position where coal isabsent due to erosion or nonde-position), and extent of all knownsurface and underground mining.Color-coded thumbnail (inset)maps on the separates enableusers to rapidly identify the arealextent and types of mining andthe relative distribution of the re-maining coal. The separate mapsalso depict the locations of allknown adits and mine shafts. Ap-propriate collar information is alsoincluded on the maps.

Brandy Camp Mapping Featuredin New PublicationExcerpts from Dodge's report wererecently highlighted in a newly re-leased (2004) publication by theAmerican Geological Institute (AGI)entitled Meeting Challenges withGeologic Maps. The 64-page AGIpublication serves to inform citi-zens, educators, and policy makersalike of the utility and versatility ofgeologic maps in providing valuableinformation to meet societal needs.One of more than two dozen au-thors contributing 16 examples ofgeologic maps and their varied uses,Dodge discussed Brandy Camp toexemplify the importance of modern-day coal mapping in Pennsylvania.

14

The Bureau of Topographicand Geologic Survey has re-leased Water Resource Report69, Hydrogeologic and Well-Construction Characteristics ofthe Rocks of Pennsylvania. Thisreport consists mainly of a Micro-soft Access database and is au-thored by staff geologists Gary M.

Fleeger, Thomas A. McElroy, andMichael E. Moore.

The database provides a state-wide statistical summary of thehydrogeologic, water-chemistry,and well-construction character-istics of the stratigraphic units onthe 1980 edition of the state geo-logic map published by the Bu-

Page-sized versions of thegeologic and coal-resource mapsare provided as well.

Digital files include a series of43 vector datasets containingpolygon, line (arc), and point fea-tures and raster datasets consist-ing of collarless georeferencedimages of the plates. Polygondatasets consist of geologic units,surface-mined areas, and under-ground-mined areas. The minecoverages contain much informa-tion about the operations. Linedatasets include structure con-tours, folds, economic coal beds,noneconomic coal beds, and keybeds that are not coals. Pointdatasets comprise adits and mineshafts, and selected drill holes,field stations, gas wells, and waterwells. The point coverages con-tain considerable information aboutthe features.

The information contained inthis report is in constant demandby many users, including the coalindustry, oil and gas companies,industrial-mineral producers, elec-trical utility companies, consul-tants, planners, government per-sonnel, academicians, and thegeneral public. The publication willbe of considerable help in explo-ration programs, coal-resource as-sessments, hydrogeological inves-tigations, land acquisition, land-use planning, and environmentalprotection and regulation.

Mineral Resource Report 99is available on CD–ROM from theState Bookstore at the addressgiven at the end of the next an-nouncement for $5.00 plus ship-ping fees and sales tax as noted.It can also be purchased over-the-counter at the Bureau’s Middletownoffice (see address on back cover).

Hydrogeologic and Well-Construction Characteristicsof the Rocks of Pennsylvania

15

reau (Berg, T. M., and others,compilers, 1980, Geologic mapof Pennsylvania, PennsylvaniaGeological Survey Map 1, scale1:250,000). Over many years,hydrogeologic studies have beencompleted in various parts of thestate by different agencies. How-ever, no statewide summariesbased on these studies have beencompiled prior to this report.

The data for the statisticalanalyses are drawn from the Penn-sylvania GroundWater Informa-tion System (PaGWIS). PaGWISincludes water well data that havebeen consolidated from varioussources. In all, data from almost50,000 field-located wells fromPaGWIS, and water-quality datafor more than 15,000 of thosewells, were used in the statisticalcalculations contained in thisdatabase. PaGWIS is availablefree of charge from the Bureau’s

web site at www.dcnr.state.pa.us/topogeo/groundwater/PaGWIS/PaGWISMain.asp. For additionalinformation about PaGWIS, pleasecontact the Bureau at 717–702–2017.

This type of analysis is muchbetter suited to digital presenta-tion than to presentation in a tra-ditional hard-copy publication. Forthat reason, the report is providedin a Microsoft Access database.However, knowledge of the use ofAccess is not necessary. The majorcategories of statistics to be dis-played are selected from a menu.Statistics are presented in easilyviewed color-coded forms, and in-structions are provided on how torestrict the display to the parame-ters that are of interest to the user.

Approximately one-half mil-lion statistics are provided for twowell-construction parameters (welldepth and casing length), four

Part of a table selected from a menu in Water Resource Report 69 showingsome of the well-construction and hydrogeologic statistics for wells in Pennsyl-vania. Colors in the published report have been modified for this presentation.

16

Sarah Andrews has written anew book in her series of murdermysteries involving Em Hansen,a geologist who uses her scien-tific skills to solve the occasionalcrime. Sarah’s latest book, EarthColors, is set in Wyoming, Wash-ington, D.C., and Pennsylvania,and includes a stop by the hero-

ine at the Pennsylvania Geologi-cal Survey. The plot focuses onthe art world, a topic that is ofstrong interest to Sarah.

Last year, Sarah led a staffretreat for the Bureau and wentwith some Bureau staff to a localunderground (in a cave) restau-rant. Bureau Director Jay Parrish

INTERVIEW

Author of New Mystery Book Combines Art and Pennsylvania Geology

hydrogeologic parameters (wellyield, specific capacity, water-bearing zones, and static waterlevel), and 34 geochemical pa-rameters, including total dissolvedsolids and pH. Statistics are bro-ken down for different strati-graphic units, physiographic sec-tions, topographic positions, andwater uses, or any combinationof those criteria.

The four main tables from thedatabase are also provided indBase IV format, which can beimported into most other data-base and spreadsheet programs.

This publication should proveuseful to consultants, regulators,water well drillers, industry, aca-demia, government agencies, andthe general public.

Water Resource Report 69may be ordered for $5.00 fromthe State Bookstore, Common-wealth Keystone Building, 400North Street, Harrisburg, PA17120–0053, telephone 717–787–5109. Payment may be madewith VISA, MasterCard, or checkor money order payable to Com-monwealth of Pennsylvania. Ifthe order is to be mailed, include$4.00 postage for one CD–ROMor book and $0.50 for each addi-tional CD–ROM or book. For Penn-sylvania residents, 6 percentsales tax must be added to thetotal cost of the order, includingshipping. The report may also bepurchased over-the-counter at theBureau’s Middletown office (seeaddress on back cover).

17

had the pleasure of accompany-ing her for a short time as shedid research for Earth Colors.Following are some questionsJay asked Sarah about her back-ground and her interests in ge-ology, art, and Pennsylvania.

What is appealing about forensicgeology? Most of geology is fo-rensic geology, that is, solvingpuzzles. It’s fun to apply geologyto particular problems of human-ity, but even here the edges getkind of fuzzy. A technical defini-tion of forensic geology is “legalgeology,” which takes in all litiga-tion, both criminal and civil. I sup-pose most people key in to thecriminal aspects, which connectsus back to the books I write, andhere I can make the obvious state-ment that people have strongfeelings about the ultimate taboo,murder. Murder mysteries comein many shapes and sizes, butthe kind I write use the intrigueof this taboo to invite readers tocontemplate other more subtlecrimes, such as theft of resourcesor human motivations of variousstripes.

Why are you so interested in art?My dad and grandmother werepainters, and I was expected tofollow them down that road. I stilldabble with pastels in my freetime, but professionally I woundup using my talents for spatialprocessing to do geology.

I understand your grandfathertaught at Bryn Mawr. Stephen

Joseph Herben, Jr., taught Chaucerand Shakespeare. He was anEnglish philologist and etymolo-gist and quite a guy. He col-lected arms and armor, and oneday dressed me and my dreadedolder brother up in helmets andbreastplates and let me whackhim with a morningstar [a spikedball attached to a chain that wasconnected to a pole]. It was de-lightful. Grampa also collectedAfrican masks and occasionallystuck cigarettes in their mouths.

What advice do you have for awould-be author? Don’t let any-one tell you how to write or whatto write until you’re really readyfor some criticism. Then take yourlumps, but advocate for the work,because if you won’t fight for it, noone will. Also, if you want to writefiction, keep in mind that there is(a) good writing, and (b) goodstorytelling, and that (a) is no-where without (b); however, thereal challenge is to join (a) and(b) together.

What are your observations aboutwomen in the geology profes-sion? Women are naturally giftedat the kind of diffuse data gather-ing that is the hallmark of geo-logic thinking. I suppose this iswhat inspired me to write abouta woman geologist; writers tendto discover themselves throughcandid self-examination, and inthe case of writing fiction, it’s self-portraiture rather than autobiog-

18

BOOK REVIEW

Earth Colorsby Sarah Andrews

raphy. I wanted to put the expe-rience of geology into the litera-ture, and, as important, recordwhat it is like to be female in amale-dominated profession. I’vehad some interesting reactionsfrom male readers who had never“been inside” a woman’s mind.

When I started in geology in1974, women made up maybefive percent of the profession.That was after we as a culturebegan to deal with sexual dis-crimination but before we beganto deal with sexual harassment.Need I mention that we still havea long way to go? One young fel-low geologist recently asked meif these were still a problem, andI asked him to tell me what colorthe walls of his office were, as in,it’s always there; but I’ll bet he’sdoing his best not to dwell on it.But at the same time, I’ve learnedthat men harass each other inthese ways and are big on dis-criminating among themselves

(the attendant term is “peckingorder,” very odd considering thatsaid metaphor springs from thebehavior of female chickens).The problems arose when menand women began interacting inthe workplace and women didnot really like being pecked, par-ticularly in ways that register asthreats. I’ve learned to be quitedirect and matter-of-fact in myresponse to such approaches,but I’d prefer not to have to dealwith it at all.

Nowadays women representa much higher fraction of thegeoscience work force, and morethan half the students in someuniversity departments, and whilewe’re still overall in the minority,we have sufficient mass that weinfluence the way the science isdone. And, as my mentor, EddieMcKee always said, “It’s a greatlife if you don’t weaken. More funif you do.” Whatever that meansin this particular case.

In Earth Colors (St. Martin’sPress Minotaur, 2004, 304 p.),Sarah Andrews continues theseries about her crime-snoopingprotagonist, Em Hansen. Em is a

forensic geologist. In this volumeshe works on the mineral con-tent of pigments in a FrederickRemington painting—or is it?—for a wealthy client from Penn-

19

sylvania. The scenes shift fluidlybetween Pennsylvania and Wyo-ming, with keen geologic detailabout both places. Her travelstake her to Utah as well, and toWashington, D.C.

In Andrews’ hands, Em is notonly a detective, but also a fullyrealized human being, with de-pressive tendencies, complicat-ed loyalties, family troubles, anda twenty-first-century love life.Sometimes she seems too whinyand yuppified, but at other times,such as when genuine humilityovertakes low self-esteem, she issympathetic and therefore genuine.

The essence of the fictiongenre is, of course, plot. At thisAndrews is accomplished. Her

story has many layers and laby-rinthine twists that tend to throwthe reader off the scent, assurely as Em moves toward it.The story deals with genera-tional conflict, with the complex-ity of adult romance, with thestrain of scholarship, and withthe difficulties of long and deepfriendships. Em is a graduate stu-dent, a single woman with multi-ple love interests, a best friendof a young widow, a kind of auntto the widow’s daughter, an air-plane pilot, and the daughter ofan alcoholic. Yes, the story goesthere, too, to the struggles withaddiction.

If that sounds like a lot of pro-tein for a mystery novel, it is.There’s enough to make one wantto see the next Andrews book.

For a Pennsylvanian, though,or a geologist, there is more yet.Andrews brings in characters todeal with the issues of farmlandpreservation in Lancaster Coun-ty. She sketches not just places,but people, modeled after realindividuals.

Through it all, Andrews man-ages to dispense some elemen-tary lessons about the geologichistory of the places she treats,a smattering of geochemistry,and a touch of geographic infor-mation systems. She does allthis without coming off the slight-est bit didactic.

—David TerrellU.S. Geological Survey

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The Bureau of Topographicand Geologic Survey, SomersetCounty Rails-to-Trails Associa-tion, and Somerset County Parksand Recreation Board, have pub-lished From Rails to Trails toRocks—Geology of the Garrett-to-Rockwood Section of theAllegheny Highlands Trail. This17-page booklet was written bystaff geologist James R. Shaulisand Thomas W. Jones, a teacherat Rockwood Area ElementarySchool. The booklet is a revisionof an article that was publishedin 2000 in Pennsylvania Geology(v. 31, no. 1, p. 12–25).

Some of the former rail bedsin Pennsylvania have been con-verted to trails where travelerscan walk and bicycle. Geologicalfeatures can be seen along thesetrails, making them excellent out-

door laboratories for students ofall ages, especially those in kin-dergarten through grade 12. Geo-logical information along a 7-milesegment between Garrett andRockwood in Somerset County ispresented in this guide. The in-formation is presented as animaginary conversation betweena student, Clay Stone, and a tourguide, Mr. GEO Ed, on a traintraveling along this section of thetrail. The conversation covers suchdiverse topics as the formation ofthe geologic units along the trail,the structure and age of the rocks,the presence of fossils, acid minedrainage, landslides, and the re-lationship between rocks and rho-dodendrons.

The booklet is available as aPDF on the Bureau’s web site atwww.dcnr.state.pa.us/topogeo/pub/index.aspx.

EARTH SCIENCE TEACHERS’ CORNER

Geology of Part of the AlleghenyHighlands Trail

CONTENTS

Getting rid of carbon dioxide .................................................................... 1Coal-bed methane—energy within reach ................................................. 2New releases ........................................................................................... 10

Earthquake catalog and epicenter map................................................ 10Brandy Camp digital coal-resource maps and datasets ....................... 12Hydrogeologic and well-construction characteristics of the rocks of

Pennsylvania.................................................................................... 14Interview—Author of new mystery book combines art and Pennsylvania

geology ................................................................................................ 16Book review—Earth Colors by Sarah Andrews ........................................ 18Earth science teachers’ corner................................................................. 20

ON THE COVER

Examples of the Bureau’s publications in the new digital format. Left toright: Map 69, Water Resource Report 69, and Mineral Resource Report99 (see articles on pages 10–16) (photograph by Clifford H. Dodge).

PENNSYLVANIA GEOLOGY

PENNSYLVANIA GEOLOGY is published quarterly by the Bureau of Topographic andGeologic Survey, Pennsylvania Department of Conservation and Natural Resources,3240 Schoolhouse Road, Middletown, PA 17057–3534.Editor: Anne B. Lutz.Contributed articles are welcome. Guidelines for manuscript preparation may be obtainedat www.dcnr.state.pa.us/topogeo/pub/pageolmag/pageolguide.aspx or by contacting theeditor at the address listed above.

VOL. 34, NO. 1 SPRING 2004

DEPARTMENT OF CONSERVATION AND NATURAL RESOURCESBUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEY

IN COOPERATION WITH THE U.S. GEOLOGICAL SURVEYTOPOGRAPHIC MAPPING

GROUNDWATER-RESOURCE MAPPING

Main Headquarters3240 Schoolhouse RoadMiddletown, PA 17057–3534717–702–2017FAX: 717–702–2065

Pittsburgh Office500 Waterfront DrivePittsburgh, PA 15222–4745412–442–4235FAX: 412–442–4298

BUREAU STAFF AND TELEPHONE NUMBERSDirector and State GeologistJay B. Parrish, P.G. 717–702–2053

Assistant DirectorSamuel W. Berkheiser,

Jr., P.G. 717–702–2055

Administrative ServicesLynn M. Goodling 717–702–2054Elizabeth C. Lyon 717–702–2063

Library ServicesRichard C. Keen 717–702–2020Lewis L. Butts, Jr. 717–702–2018

Publication ServicesJody R. Zipperer

(General Inquiries) 717–702–2073Christine E. Miles, P.G. 717–702–2044Caron E. O’Neil, P.G. 717–702–2042Anne B. Lutz 717–702–2043

Local Government Outreach ServicesKristen L. Reinertsen

(East) 717–702–2047Jaime Kostelnik (West) 412–442–5828

Database ServicesCheryl L. Cozart 412–442–4234Janice Hayden 412–442–4287Joseph E. Kunz 412–442–4235Lynn J. Levino 412–442–4299Karen L. McCoy (Oil and

Gas GIS Services) 412–442–5826

GIS ServicesMichael E. Moore, P.G. 717–702–2024John H. Barnes, P.G. 717–702–2025Thomas G. Whitfield, P.G. 717–702–2023

GIS Services (continued)Stuart O. Reese, P.G. 717–702–2028Thomas K. Yeager, P.G. 717–702–2026

Water Well ServicesSharon E. Fesus 717–702–2074Jody R. Zipperer 717–702–2073

Groundwater ServicesGary M. Fleeger, P.G. 717–702–2045Thomas A. McElroy, P.G. 717–702–2046

Geologic Mapping ServicesJon D. Inners, P.G. 717–702–2034Gale C. Blackmer 717–702–2032Helen L. Delano, P.G. 717–702–2031Clifford H. Dodge, P.G. 717–702–2036William E. Kochanov, P.G. 717–702–2033James R. Shaulis, P.G. 717–702–2037Viktoras W. Skema, P.G. 717–702–2035

Laboratory and Geochemical ServicesRobert C. Smith, II, P.G. 717–702–2021Leslie T. Chubb 717–702–2022

Coal-Bed Methane ServicesAntonette K. Markowski,

P.G. 717–702–2038

Coal Quality and Availability ServicesRodger T. Faill, P.G. 717–702–2041Leonard J. Lentz, P.G. 717–702–2040John C. Neubaum 717–702–2039

Oil, Gas, and Subsurface GeologicalServicesJohn A. Harper, P.G. 412–442–4230Christopher D. Laughrey 412–442–4232Joseph R. Tedeski 412–442–4295Kristin M. Carter, P.G. 412–442–4233

COMMONWEALTH OF PENNSYLVANIAEdward G. Rendell, Governor

DEPARTMENT OF CONSERVATION AND NATURAL RESOURCESMichael DiBerardinis, Secretary

OFFICE OF CONSERVATION AND ENGINEERING SERVICESRichard G. Sprenkle, Deputy Secretary

BUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEYJay B. Parrish, Director

Bureau web site: www.dcnr.state.pa.us/topogeoDCNR web site: www.dcnr.state.pa.us

Pennsylvania home page: www.state.pa.us

Bureau of Topographic and Geologic SurveyDepartment of Conservation and Natural Resources3240 Schoolhouse RoadMiddletown, PA 17057–3534

Address Service Requested

PRSRT STDU.S. Postage

PAIDHarrisburg, PAPermit No. 747

COAL-BED METHANE WELLS IN PENNSYLVANIA(From Markowski, 2001, p. 44)

(See article on page 2.)

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