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Molluscan faunal distribution in Florida Bay, past and present: An integration of down-core and modern data Molluscan faunal distribution in Florida Bay, past and present: An integration of down-core and modern data

Statistical comparison of modern molluscan fauna to down-core molluscan assemblages in four cores elucidates changes in the Florida Bay ecosystem during the past 100 to 200 years. Fluctuations within molluscan faunal dominance and diversity patterns suggest a response to changing environmental conditions. Faunal dominance patterns indicate an increase in salinity in the northern...
Authors
G. Lynn Wingard, Jeffrey D. Stoner, Charles W. Holmes

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

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

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
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