Northeastern (46th Annual) and North-Central (45th Annual) Joint Meeting (20–22 March 2011)

Paper No. 3
Presentation Time: 8:00 AM-12:00 PM


LEITKAM, Stephen1, EDENBORN, Harry M.2, CAPO, Rosemary C.3, EDENBORN, Sherie L.4, SHARMA, Shikha5, HARTSOCK, Angela2, SHAULIS, James R.6, WOODS, Peter7 and VESPER, Dorothy J.8, (1)PA Dept. Environmental Protection, 25 Technology Drive, Coal Center, PA 15423, (2)Geosciences Division, National Energy Technology Lab; U.S. Department of Energy, Pittsburgh, PA 15236, (3)Department of Geology & Planetary Science, University of Pittsburgh, Pittsburgh, PA 15260, (4)Natural & Physical Sciences Division, Chatham University, 128C Buhl Hall, Pittsburgh, PA 15232, (5)Geology and Geography, West Virginia University, 330 Brooks Hall, 98 Beechurst Avenue, Morgantown, WV 26506, (6)Pennsylvania Department of Conservation and Natural Resources , Bureau of Topographic and Geologic Survey, Bureau of Topographic and Geologic Survey, 3240 Schoolhouse Road, Middletown, PA 17057-3534, (7)Western Pennsylvania Conservancy, 800 Waterfront Drive, Pittsburgh, PA 15222, (8)Department of Geology & Geography, West Virginia University, Morgantown, WV 26506,

Active calcium carbonate precipitation and accretion around springs and other groundwater seepages, related to the degassing of carbon dioxide, results in formations variably referred to as tufa or travertine. Such deposits in eastern North America are especially well-known in the karst region of western Virginia, often associated with the discharge of thermal spring waters, but reports of tufa formations outside of this region are scanty. Here we report on our preliminary observations on the occurrence of tufa in western Pennsylvania associated with springs and seeps adjacent to limestone units. The Upper Pennsylvanian Monongahela Group Benwood Limestone and the Middle Pennsylvanian Allegheny Group Vanport Limestone provide the likely source of calcium for the carbonate minerals that make up the deposits. Most tufa occurrences in the study area can be classified as perched springline tufas that are lobate, convex to flat-surfaced deposits, thickening away from a spring mouth. Many of the discovered sites are associated with human disturbances of natural terrain during the past 150 years that resulted in steep elevational drops in discharged water and enhanced carbon dioxide release – these include such activities as highway and railroad construction and the strip mining of bituminous coal. Preliminary data illustrating the general chemical, geological and biological characteristics of these tufa sites and their corresponding waters are presented. Future multidisciplinary scientific studies of these sites will incorporate geology, geochemistry, microbiology, isotopic analysis, hydrology and ecology.