The Marcellus Shale of the Appalachian Basin is one of the largest unconventional gas plays in the United States.
The Marcellus Shale is the most extensive of a series of Appalachian black-shale formations deposited in sediment-starved subsiding foreland basins during the Devonian Period. The targeted black shales in the Marcellus, which are delineated on geophysical logs by their elevated gamma radiation and low density, are organic rich and pyritic.
The Marcellus play is being developed in Pennsylvania, West Virginia, and Ohio at depths between 5,000 and 9,000 feet below land surface. Typically, six horizontal legs 4,000 feet long are drilled in the basal Marcellus per multi-well pad and 3 to 5 million gallons of water are used to hydraulically fracture each leg.
Water-resource issues associated with development of the Marcellus play include the 1) impact of surface-water and groundwater withdrawals for hydraulic fracturing during low-flow periods, 2) disposal of black-shale drill cuttings that may produce acidic, metals-rich drainage with elevated radioisotopes, and 3) treatment of hydraulic-fracturing flowback that contains elevated dissolved solids and radioisotopes. Surface spills of hydraulic-fracturing fluids and flowback and problems with casing and grout seals that allow migration of gas to freshwater aquifers pose the greatest threats to the water resources.
Related Links:
Survey of Low-Flow Stream Water Specific Conductance in the Southern Tier of New York State
Water issues and the Marcellus Shale gas development in NY (NYWSC News Release)
Water-Supply Considerations within the Marcellus Shale Gas-Play Area of New York State (Handout)
Upstate New York Unconsolidated Aquifer Mapping Program (GIS Coverages)
Below are publications associated with this project.
Methane occurrence in groundwater of south-central New York State, 2012: summary of findings
Occurrence of methane in groundwater of south-central New York State, 2012-systematic evaluation of a glaciated region by hydrogeologic setting
Dissolved methane in groundwater, Upper Delaware River Basin, Pennsylvania and New York, 2007-12
Water resources and shale gas/oil production in the Appalachian Basin: critical issues and evolving developments
Specific conductance measurements in central and western New York streams - A retrospective characterization
Dissolved methane in New York groundwater, 1999-2011
Baseline groundwater quality in national park units within the Marcellus and Utica Shale gas plays, New York, Pennsylvania, and West Virginia, 2011
Water Resources and Natural Gas Production from the Marcellus Shale
- Overview
The Marcellus Shale of the Appalachian Basin is one of the largest unconventional gas plays in the United States.
Exposure of the Marcellus shale in central New York showing the Cherry Valley limestone (grey-colored rock) between the Union Springs and Oatka Creek shales of the Marcellus. (Credit: John Williams, USGS. Public domain.) The Marcellus Shale is the most extensive of a series of Appalachian black-shale formations deposited in sediment-starved subsiding foreland basins during the Devonian Period. The targeted black shales in the Marcellus, which are delineated on geophysical logs by their elevated gamma radiation and low density, are organic rich and pyritic.
The Marcellus play is being developed in Pennsylvania, West Virginia, and Ohio at depths between 5,000 and 9,000 feet below land surface. Typically, six horizontal legs 4,000 feet long are drilled in the basal Marcellus per multi-well pad and 3 to 5 million gallons of water are used to hydraulically fracture each leg.
Water-resource issues associated with development of the Marcellus play include the 1) impact of surface-water and groundwater withdrawals for hydraulic fracturing during low-flow periods, 2) disposal of black-shale drill cuttings that may produce acidic, metals-rich drainage with elevated radioisotopes, and 3) treatment of hydraulic-fracturing flowback that contains elevated dissolved solids and radioisotopes. Surface spills of hydraulic-fracturing fluids and flowback and problems with casing and grout seals that allow migration of gas to freshwater aquifers pose the greatest threats to the water resources.
Typical well drilling tower with associated equipment (Credit: John WIlliams, USGS. Public domain.) Related Links:
Survey of Low-Flow Stream Water Specific Conductance in the Southern Tier of New York State
Water issues and the Marcellus Shale gas development in NY (NYWSC News Release)
Water-Supply Considerations within the Marcellus Shale Gas-Play Area of New York State (Handout)
Upstate New York Unconsolidated Aquifer Mapping Program (GIS Coverages)
Mixing of drill cuttings with absorbent polymer prior to shipping and disposal in a secured landfill. (Credit: John Williams, USGS. Public domain.) - Publications
Below are publications associated with this project.
Methane occurrence in groundwater of south-central New York State, 2012: summary of findings
A survey of methane in groundwater was undertaken to document methane occurrence on the basis of hydrogeologic setting within a glaciated 1,810-square-mile area of south-central New York that has not seen shale-gas resource development. The adjacent region in northeastern Pennsylvania has undergone shale-gas resource development from the Marcellus Shale. Well construction and subsurface data wereAuthorsPaul M. Heisig, Tia-Marie ScottOccurrence of methane in groundwater of south-central New York State, 2012-systematic evaluation of a glaciated region by hydrogeologic setting
A survey of methane in groundwater was undertaken to document methane occurrence on the basis hydrogeologic setting within a glaciated 1,810-square-mile area of south-central New York along the Pennsylvania border. Sixty-six wells were sampled during the summer of 2012. All wells were at least 1 mile from any known gas well (active, exploratory, or abandoned). Results indicate strong positive andAuthorsPaul M. Heisig, Tia-Marie ScottDissolved methane in groundwater, Upper Delaware River Basin, Pennsylvania and New York, 2007-12
The prospect of natural gas development from the Marcellus and Utica Shales has raised concerns about freshwater aquifers being vulnerable to contamination. Well owners are asking questions about subsurface methane, such as, “Does my well water have methane and is it safe to drink the water?” and “Is my well system at risk of an explosion hazard associated with a combustible gas like methane in grAuthorsWilliam M. KappelWater resources and shale gas/oil production in the Appalachian Basin: critical issues and evolving developments
Unconventional natural gas and oil resources in the United States are important components of a national energy program. While the Nation seeks greater energy independence and greener sources of energy, Federal agencies with environmental responsibilities, state and local regulators and water-resource agencies, and citizens throughout areas of unconventional shale gas development have concerns aboAuthorsWilliam M. Kappel, John H. Williams, Zoltan SzaboSpecific conductance measurements in central and western New York streams - A retrospective characterization
U.S. Geological Survey (USGS) Data Rescue Program funds were used to recover data from paper records for 139 streamgages across central and western New York State; 6,133 different streamflow measurement forms, collected between 1970-80, contained field water-quality measurements. The water-quality data were entered, reviewed, and uploaded into the USGS National Water Information System. In total,AuthorsWilliam M. Kappel, Gaylen J. Sinclair, James E. Reddy, David A. Eckhardt, M. Peter deVries, Margaret E. PhillipsDissolved methane in New York groundwater, 1999-2011
New York State is underlain by numerous bedrock formations of Cambrian to Devonian age that produce natural gas and to a lesser extent oil. The first commercial gas well in the United States was dug in the early 1820s in Fredonia, south of Buffalo, New York, and produced methane from Devonian-age black shale. Methane naturally discharges to the land surface at some locations in New York. At ChestnAuthorsWilliam M. Kappel, Elizabeth A. NystromBaseline groundwater quality in national park units within the Marcellus and Utica Shale gas plays, New York, Pennsylvania, and West Virginia, 2011
Groundwater samples were collected from 15 production wells and 1 spring at 9 national park units in New York, Pennsylvania, and West Virginia in July and August 2011 and analyzed to characterize the quality of these water supplies. The sample sites generally were selected to represent areas of potential effects on water quality by drilling and development of gas wells in Marcellus Shale and UticaAuthorsDavid A.V. Eckhardt, Ronald A. SlotoWater Resources and Natural Gas Production from the Marcellus Shale
The Marcellus Shale is a sedimentary rock formation deposited over 350 million years ago in a shallow inland sea located in the eastern United States where the present-day Appalachian Mountains now stand (de Witt and others, 1993). This shale contains significant quantities of natural gas. New developments in drilling technology, along with higher wellhead prices, have made the Marcellus Shale anAuthorsDaniel J. Soeder, William M. Kappel