Publications
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Studies of the Chesapeake Bay impact structure - Introduction and discussion Studies of the Chesapeake Bay impact structure - Introduction and discussion
The late Eocene Chesapeake Bay impact structure on the Atlantic margin of Virginia is the largest known impact crater in the United States, and it may be the Earth's best preserved example of a large impact crater that formed on a predominantly siliciclastic continental shelf. The 85-kilometer-wide (53-milewide) crater also coincides with a region of saline ground water. It has a...
Authors
J. Wright Horton,, David Powars, Gregory Gohn
Crystalline-rock ejecta and shocked minerals of the Chesapeake Bay impact structure, USGS-NASA Langley core, Hampton, Virginia, with supplemental constraints on the age of impact Crystalline-rock ejecta and shocked minerals of the Chesapeake Bay impact structure, USGS-NASA Langley core, Hampton, Virginia, with supplemental constraints on the age of impact
The USGS-NASA Langley corehole at Hampton, Va., was drilled 2000 as the first in a series of new coreholes drilled in the late Eocene Chesapeake Bay impact structure to gain a comprehensive understanding of its three-dimensional character. This understanding is important for assessing ground-water resources in the region, as well as for learning about marine impacts on Earth. We studied
Authors
J. Wright Horton,, G. A. Izett
High-resolution seismic-reflection image of the Chesapeake Bay impact structure, NASA Langley Research Center, Hampton, Virginia High-resolution seismic-reflection image of the Chesapeake Bay impact structure, NASA Langley Research Center, Hampton, Virginia
A 1-kilometer-long (0.62-mile-long) seismic reflection and refraction profile collected at the National Aeronautics and Space Administration (NASA) Langley Research Center, Hampton, Va., provides a detailed image of part of the annular trough of the buried, 35-million-year-old Chesapeake Bay impact structure. This profile passes within 5 meters (m; 16.4 feet (ft)) of a 635.1-m-deep (2...
Authors
Rufus Catchings, David Powars, Gregory Gohn, Mark Goldman
Paleontology of the upper Eocene to quaternary postimpact section in the USGS-NASA Langley core, Hampton, Virginia Paleontology of the upper Eocene to quaternary postimpact section in the USGS-NASA Langley core, Hampton, Virginia
The USGS-NASA Langley corehole was drilled in 2000 in Hampton, Va. The core serves as a benchmark for the study of calcareous nannofossils, dinoflagellates, diatoms and silico flagellates, mollusks, ostracodes, planktonic foraminifera and bolboformids, and vertebrate remains in the upper Eocene, Oligocene, Miocene, and Pliocene sediments in southeastern Virginia. These sediments were...
Authors
Lucy Edwards, John Barron, David Bukry, Laurel Bybell, Thomas Cronin, C. Poag, Robert Weems, G. Wingard
Studies of the Chesapeake Bay impact structure: The USGS-NASA Langley corehole, Hampton, Virginia, and related coreholes and geophysical surveys Studies of the Chesapeake Bay impact structure: The USGS-NASA Langley corehole, Hampton, Virginia, and related coreholes and geophysical surveys
No abstract available.
Authors
J. Wright Horton, David Powars, Gregory S. Gohn
Taxonomic revision and stratigraphic provenance of 'Histiophorus rotundu' Woodward 1901 (Teleostei, Perciformes) Taxonomic revision and stratigraphic provenance of 'Histiophorus rotundu' Woodward 1901 (Teleostei, Perciformes)
Until recently, †Histiophorus rotundus Woodward 1901, was known from a single, poorly preserved rostrum from the Tertiary phosphate beds near Charleston, South Carolina, an area from which many fossils have been described. The specimen is relatively featureless externally; its internal anatomy is unknown and the documentation of its geological provenance was poor. In an earlier revision...
Authors
K. Monsch, H. L. Fierstine, Robert Weems
North American Commission on stratigraphic nomenclature North American Commission on stratigraphic nomenclature
No abstract available.
Authors
R. Easton, J.O. Jones, A.C. Lenz, Ismael Ferrusquia-Villafranca, E. Mancini, Bruce Wardlaw, Lucy Edwards, B.R. Pratt
Cascading ecological effects of low-level phosphorus enrichment in the Florida Everglades Cascading ecological effects of low-level phosphorus enrichment in the Florida Everglades
Few studies have examined long-term ecological effects of sustained low-level nutrient enhancement on wetland biota. To determine sustained effects of phosphorus (P) addition on Everglades marshes we added P at low levels (5, 15, and 30 μg L−1 above ambient) for 5 yr to triplicate 100-m flow-through channels in pristine marsh. A cascade of ecological responses occurred in similar...
Authors
Evelyn Gaiser, Joel Trexler, Jennifer Richards, Daniel L. Childers, David Lee, A. Edwards, Leonard Scinto, Krish Jayachandran, Gregory Noe, Ronald D. Jones
Head-bobbing behavior in foraging whooping cranes favors visual fixation Head-bobbing behavior in foraging whooping cranes favors visual fixation
No abstract available.
Authors
Thomas Cronin, Matthew Kinloch, Glenn Olsen
Deciphering multiple Mesoproterozoic and Paleozoic events recorded in zircon and titanite from the Baltimore Gneiss, Maryland: SEM imaging, SHRIMP U-Pb geochronology, and EMP analysis Deciphering multiple Mesoproterozoic and Paleozoic events recorded in zircon and titanite from the Baltimore Gneiss, Maryland: SEM imaging, SHRIMP U-Pb geochronology, and EMP analysis
The Baltimore Gneiss, exposed in antiforms in the eastern Maryland Piedmont, consists of a suite of felsic and mafic gneisses of Mesoproterozoic age. Zircons from the felsic gneisses are complexly zoned, as shown in cathodoluminescence imaging; most zircon grains have multiple overgrowth zones, some of which are adjacent and parallel to elongate cores. Sensitive high-resolution ion...
Authors
John Aleinikoff, J. Wright Horton,, Avery Drake, R. P. Wintsch, C.M. Fanning, K. Yi
Ecosystem history of southern and central Biscayne Bay: Summary report on sediment core analyses - year two Ecosystem history of southern and central Biscayne Bay: Summary report on sediment core analyses - year two
The Comprehensive Everglades Restoration Plan (CERP) lists restoration of the timing, quantity, and quality of the natural flow of freshwater as one its primary goals. Before restoration can occur, however, the baseline conditions of the environment prior to significant human alteration must be established and the range of variation within the natural system must be determined. In...
Authors
G. Wingard, Thomas Cronin, Charles Holmes, Debra Willard, Gary S. Dwyer, Scott Ishman, William Orem, Christopher Williams, Jessica Albietz, Christopher Bernhardt, Carlos Budet, Bryan Landacre, Terry Lerch, Marci Marot, Ruth Ortiz
Bedrock geologic map of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut Bedrock geologic map of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut
The bedrock geology of the New Milford quadrangle, Litchfield and Fairfield Counties, Connecticut is described in this report. The database includes contacts of bedrock geologic units, faults, outcrops, structural geologic information, and photos.
Authors
Gregory Walsh