Publications
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Geochemical changes in crude oil spilled from the Exxon Valdez supertanker into Prince William Sound, Alaska
North Slope crude oil spilled from the T/V Exxon Valdez in March 1989 and contaminated about 500 km of Prince William Sound shoreline. Aliphatic and aromatic hydrocarbons in oil samples collected in August 1990 and June 1992 from beaches on six islands impacted by the spill have been compared with the hydrocarbons from North Slope crude oil taken from the stricken tanker. Degradation processes hav
Authors
Frances D. Hostettler, Keith A. Kvenvolden
Decade-scale trend in sea water salinity revealed through d18O analysis of Montastraea annularis annual growth bands
Stable oxygen isotope ratios (1)180) of coral skeletons are influenced by ambient water temperature and by the oxygen isotope ratio in the surrounding sea water, which, in turn, is linked to evaporation (salinity) and precipitation. To investigate this relationship more thoroughly, we collected hourly temperature data from the Hen and Chickens Reef in the Florida Keys between 1975 and 1988 and com
Authors
Robert B. Halley, Peter K. Swart, Richard E. Dodge, J. Harold Hudson
Vertical structure of mean cross-shore currents across a barred surf zone
Mean cross-shore currents observed across a barred surf zone are compared to model predictions. The model is based on a simplified momentum balance with a turbulent boundary layer at the bed. Turbulent exchange is parameterized by an eddy viscosity formulation, with the eddy viscosity Aυ independent of time and the vertical coordinate. Mean currents result from gradients due to wave breaking and s
Authors
John W. Haines, Asbury H. Sallenger
Deep structure beneath Lake Ontario: Crustal-scale Grenville subdivisions
Lake Ontario marine seismic data reveal major Grenville crustal subdivisions beneath central and southern Lake Ontario separated by interpreted shear zones that extend to the lower crust. A shear zone bounded transition between the Elzevir and Frontenac terranes exposed north of Lake Ontario is linked to a seismically defined shear zone beneath central Lake Ontario by prominent aeromagnetic and gr
Authors
D. A. Forsyth, B. Milkereit, Colin A. Zelt, D. J. White, R. M. Easton, Deborah R. Hutchinson
Large-scale deformation related to the collision of the Aleutian Arc with Kamchatka
The far western Aleutian Island Arc is actively colliding with Kamchatka. Westward motion of the Aleutian Arc is brought about by the tangential relative motion of the Pacific plate transferred to major, right-lateral shear zones north and south of the arc. Early geologic mapping of Cape Kamchatka (a promontory of Kamchatka along strike with the Aleutian Arc) revealed many similarities to the geol
Authors
Eric L. Geist, David W. Scholl
Seismic images of a tectonic subdivision of the Greenville Orogen beneath lakes Ontario and Erie
New seismic data from marine air-gun and Vibroseis profiles in Lake Ontario and Lake Erie provide images of subhorizontal Phanerozoic sediments underlain by a remarkable series of easterly dipping reflections that extends from the crystalline basement to the lower crust. These reflections are interpreted as structural features of crustal-scale subdivisions within the Grenville Orogen. Broadly defo
Authors
D. A. Forsyth, B. Milkereit, A. Davidson, S. Hanmer, Deborah R. Hutchinson, W. J. Hinze, R.F. Mereu
Lake Michigan's late Quaternary limnological and climate history from ostracode, oxygen isotope, and magnetic susceptibility
The limnology of Lake Michigan has changed dramatically since the late Pleistocene in response to the expansion and contraction of continental glaciers, to differential isostatic rebound, and to climate change. The lake sediment's stratigraphic trends, magnetic susceptibility, δ18O, and ostracode species abundance ratios provide criteria to identify the lake's response to glacial ice and to differ
Authors
Richard M. Forester, Steven M. Colman, Richard L. Reynolds, Loyd D. Keigwin
Overview of the southern Lake Michigan coastal erosion study
No abstract available.
Authors
David W. Folger, Steven M. Colman, Peter W. Barnes
Convective heat discharge of Wood River group of springs in the vicinity of Crater Lake, Oregon
Data sets for spring and stream chemistry are combined to estimate convective heat discharge and discharge anomalous amounts of sodium and chloride for the Wood River group of springs south of Crater Lake. The best estimate of heat discharge is 87 MWt based on chloride inventory; this value is 3-5 times the heat input to Crater Lake itself. Anomalous discharges of sodium and chloride are also larg
Authors
Manuel Nathenson, Robert H. Mariner, J. Michael Thompson
Lake-level history of Lake Michigan for the past 12,000 years: the record from deep lacustrine sediments
Collection and analysis of an extensive set of seismic-reflection profiles and cores from southern Lake Michigan have provided new data that document the history of the lake basin for the past 12,000 years. Analyses of the seismic data, together with radiocarbon dating, magnetic, sedimentologic, isotopic, and paleontologic studies of core samples, have allowed us to reconstruct lake-level changes
Authors
Steven M. Colman, Richard M. Forester, Richard L. Reynolds, Donald S. Sweetkind, John W. King, Paul Gangemi, Glenn A. Jones, Loyd D. Keigwin, David S. Foster
The Geology of Gaspra
The surface of Gaspra can be divided into several facets separated by ridges. Superimposed on the facets and ridges are two populations of craters. Type 1 craters are crisply defined and constitute a production function of impact origin. Type 2 craters are mostly irregular shallow depressions and probably of various origins. Some of the type 2 craters may have formed by impact and be remnants of a
Authors
M. H. Carr, Randolph L. Kirk, A. McEwen, J. Veverka, P. Thomas, J.W. Head, S. Murchie
Channelized subglacial drainage over a deformable bed
We develop theoretically a description of a possible subglacial drainage mechanism for glaciers and ice sheets moving over saturated, deformable till. The model is based on the plausible assumption that flow of water in a thin film at the ice-till interface is unstable to the formation of a channelized drainage system, and is restricted to the case in which meltwater cannot escape through the till
Authors
J. S. Walder, A. Fowler