Publications
Filter Total Items: 921
Knickzone propagation in the Black Hills and northern High Plains: A different perspective on the late Cenozoic exhumation of the Laramide Rocky Mountains Knickzone propagation in the Black Hills and northern High Plains: A different perspective on the late Cenozoic exhumation of the Laramide Rocky Mountains
Geomorphic research in the Black Hills and northern High Plains poses an intriguing hypothesis for the Cenozoic evolution of this salient of the Laramide Rockies. Most recently, geologists have appealed to late Cenozoic epeirogenic uplift or climate change to explain the post-Laramide unroofing of the Rockies. On the basis of field mapping and the interpretation of long-valley profiles...
Authors
Brent J. Zaprowski, Edward B. Evenson, Frank J. Pazzaglia, Jack B. Epstein
Preliminary lithogeochemical map showing near-surface rock types in the Chesapeake Bay watershed, Virginia and Maryland Preliminary lithogeochemical map showing near-surface rock types in the Chesapeake Bay watershed, Virginia and Maryland
This preliminary experimental lithogeochemical map shows the distribution of rock types in the Virginia and Maryland parts of the Chesapeake Bay watershed. The map was produced digitally by classifying geologic-map units according to composition, mineralogy, and texture; rather than by age and stratigraphic relationships as shown on traditional geologic maps. This map differs from most...
Authors
John D. Peper, Lucy McCartan, J. Wright Horton, James E. Reddy
Gypsum-karst collapse in the Black Hills, South Dakota-Wyoming, USA Gypsum-karst collapse in the Black Hills, South Dakota-Wyoming, USA
No abstract available.
Authors
Jack B. Epstein
Kaolinite distribution in Paleocene/Eocene boundary strata of northeastern United States and Pakistan – climatic and stratigraphic implications Kaolinite distribution in Paleocene/Eocene boundary strata of northeastern United States and Pakistan – climatic and stratigraphic implications
No abstract available.
Authors
Thomas G. Gibson, Laurel M. Bybell, Ellen Thomas, James C. Zachos
The East Range, northwestern Nevada: A neglected key to the tectonic history of the region The East Range, northwestern Nevada: A neglected key to the tectonic history of the region
The East Range occupies a strategic position at the western edge of the exposed western facies terrane near the Paleozoic continental margin. There a Cambrian and Ordovician deep-water sequence including the Preble and Valmy Formations is overlain by middle to upper Paleozoic strata that are assigned to three separate stratigraphic sequences on published geologic maps of the range. The...
Authors
Keith B. Ketner, Bruce R. Wardlaw, Anita G. Harris, John E. Repetski
Planktic foraminifer census data from the northwestern Gulf of Mexico Planktic foraminifer census data from the northwestern Gulf of Mexico
No abstract available.
Authors
Harry J. Dowsett, Richard Z. Poore
Constraints on timing and rates of late Cenozoic incision by the Colorado River in Glenwood Canyon, Colorado: A preliminary synopsis Constraints on timing and rates of late Cenozoic incision by the Colorado River in Glenwood Canyon, Colorado: A preliminary synopsis
No abstract available.
Authors
Robert M. Kirkham, Michael J. Kunk, Bruce Bryant, Randall K. Streufert
Digital airborne time domain electromagnetic data from surveys over Cochiti Pueblo, Rio Puerco, and Rio Rancho, New Mexico Digital airborne time domain electromagnetic data from surveys over Cochiti Pueblo, Rio Puerco, and Rio Rancho, New Mexico
The Albuquerque-Santa Fe region is rapidly growing. The Santa Fe Group aquifer in the Middle Rio Grande Basin (MRGB) is the main source of municipal water for the greater Albuquerque metropolitan area and is more limited than previously thought (Thorn et al., 1993). The MRGB, as defined hydrologically and used here, is the area within the Rio Grande Valley extending from Cochiti Dam...
Authors
Maria Deszcz-Pan, B. D. Rodriguez, J. P. Doucette, Michel Godbout, J. M. Williams, D.A. Sawyer, B. D. Stone, V.J. Grauch
Preliminary stratigraphic database for the subsurface Tertiary and uppermost Cretaceous sediments of Dorchester County, South Carolina Preliminary stratigraphic database for the subsurface Tertiary and uppermost Cretaceous sediments of Dorchester County, South Carolina
No abstract available.
Authors
Gregory Gohn, Laurel M. Bybell, Pete G. Chirico, R. A. Christopher, Lucy E. Edwards, N. O. Frederiksen, D.C. Prowell, Jean Self-Trail, Robert E. Weems
Hydrogeologic setting and potential for denitrification in ground water, Coastal Plain of southern Maryland Hydrogeologic setting and potential for denitrification in ground water, Coastal Plain of southern Maryland
The types and distribution of Coastal Plain sediments in the Patuxent River Basin may contribute to relatively low concentrations of nitrate (typically less than 1 milligram per liter) in stream base flow because of the chemical reduction of dissolved nitrate (denitrification) in ground water. Water chemistry data from synoptic stream base-flow surveys in the Patuxent River Basin show...
Authors
David E. Krantz, David S. Powars