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Not all publications have extents, not all extents are completely accurate
Pacific Coast coccolith stratigraphy between Point Conception and Cabo Corrientes, Deep Sea Drilling Project Leg 63
David Bukry
1981, Initial Reports of the D.S.D.P. (63) 445-471
DSDP Leg 63 recovered Neogene coccoliths from south of Point Conception, California (Site 467), to north of Cabo Corrientes, Mexico (Site 473), as part of a traverse exploring the sedimentary record of the California Current along the Pacific Coast. A combination of temperate and tropical zonations were used to date...
Silicoflagellate stratigraphy of offshore California and Baja California, Deep Sea Drilling Project, Leg 63.
David Bukry
1981, Initial Reports of the D.S.D.P. (63) 539-557
Quantitative study of middle and upper Miocene silicoflagellate assemblages from Pacific Coast Sites 467 and 469 to 472 has permitted identification of warm- and temperate-water biostratigraphic zones and the formulation of a model for relative paleotemperature values (Ts) on the basis of warm- and temperate-genera abundances. Geographic and temporal trends...
Swash mark and grain flow
Sallenger Jr.
1981, Journal of Sedimentary Petrology (51) 261-264
Swash marks composed entirely of coarse sand are commonly found on coarse-sand beaches. These swash marks are 10 to 30 centimeters in width and a few millimeters to one centimeter in height. Previous observations, mostly on finer-sand beaches, indicate swash marks are seldom over a few millimeters in height and...
Geomorphology and sediment stability of a segment of the U.S. continental slope off New Jersey
James M. Robb, J.C. Hampson Jr., D.C. Twichell
1981, Science (211) 935-937
The morphology of complex deposits of Pleistocene sediments covering the upper continental slope between Lindenkohl Canyon and South Toms Canyon results from both depositional and erosional processes. Small slump or slide features were detected primarily on the flanks of canyons or valleys and were observed to occur...
Cenozoic coccoliths from the Deep Sea Drilling Project
David Bukry
1981, Book chapter, The Deep Sea Drilling Project: A Decade of Progress
Coccoliths, as the dominant constituent of many Deep Sea Drilling Project cores, have provided the means of rapid and detailed biostratigraphic zonation to help guide ocean-sediment coring operations aboard D.V. Glomar Challenger. The Cenozoic has been divided into 50 to 60 zones and subzones which are most effective for middle- and low-...
Age estimations based on amino acid racemization: Reply to comments of J.F. Wehmiller
Keith A. Kvenvolden, D. Blunt, H. Edward Clifton
1981, Geochimica et Cosmochimica Acta (45) 205-207
Determining geologic ages of fossils by amino acid racemization techniques is often difficult because of the uncertainties in assumptions about diagenetic temperatures. Two kinetic model methods have been employed. Method 1, used by us, assumes that racemization of amino acids in the bivalve mollusk Saxidomus giganteus from Willapa Bay, Washington, follows linear...
Geochemistry of amino acids in sediments from Clear Lake, California
D. Blunt, Keith A. Kvenvolden, John D. Sims
1981, Geology (9) 378-382
By studying the geochemistry of amino acids, we attempt to clarify uncertainties in the radiocarbon chronology and in correlations of ash beds and pollen spectra in lacustrine sediment from Clear Lake, California. Two amino acids, aspartic acid and alanine, are considered in detail. Relative concentrations of aspartic acid decrease with...
Thermogenic hydrocarbons in unconsolidated sediment of Eel river basin, offshore northern California
Keith A. Kvenvolden, Michael E. Field
1981, AAPG Bulletin (65) 1642-1646
Thermally produced hydrocarbons were recovered from unconsolidated sediment ponded within a bathymetric depression on the surface of a shale diapir in the offshore Eel River Basin of northern California. Evidence that the hydrocarbons are thermogenic consists of the following: (1) very high concentrations of hydrocarbon gases, particularly ethane through butanes...
Organic geochemistry in the Deep Sea Drilling Project
Keith A. Kvenvolden
1981, Society of Economic Geologists Special Publication (32) 227-249
Since the beginning of the Deep Sea Drilling Project DSDP in 1968 and extending through 1975 organic geochemical studies have been undertaken on about 2300 samples recovered on Legs I through 44 from sediments beneath the ocean floors These studies have provided fundamental information regarding the distribution of carbon in...
Smooth seaward-dipping horizons — An important factor in sea-floor stability?
B.A. McGregor
1981, Marine Geology (39) M89-M98
Mass movement has influenced in varying degrees the morphology of the United States east coast continental margin seaward of the Baltimore Canyon trough as revealed by detailed geophysical studies using high-resolution 3.5-kHz, and seismic reflection data. Each of three areas studied is along the slope within a distance of 225...
The effect of snowmelt on the water quality of Filson Creek and Omaday Lake, northeastern Minnesota
D. I. Siegel
1981, Water Resources Research (17) 238-242
Sulfate concentration and pH were determined in surface water, groundwater, and precipitation samples collected in the Filson Creek watershed to evaluate the sources of sulfate in Filson Creek. During and immediately after snowmelt, sulfate concentrations in Filson Creek increased from about 2 to 14 mg/l. Concurrently, H+ ion activity increased from an...
Depletion sampling in stream ecosystems: assumptions and techniques
Robert F. Raleigh, Cathleen Short
1981, Progressive Fish-Culturist (43) 115-120
Reliable fish and invertebrate population estimates depend on meeting the assumptions of the methods used for organism capture and data analysis. A review of several population estimation studies has indicated that assumptions of the removal method for population estimation are often violated. This paper outlines (1) procedures to assist in...
IASPEI workshop: Seismic modeling of laterally varying structures
Walter D. Mooney
1981, Eos, Transactions, American Geophysical Union (62) 18-19
During the past 10 years, significant progress has been made in the methods of collection and analysis of seismic reflection and refraction data. This progress has led to the development of new models for the structure and composition of the earth's crust, based on sophisticated analysis of...
The geologic history of the Mid-Pacific Mountains in the central North Pacific Ocean; A synthesis of deep-sea drilling studies
Jorn Thiede, Walter E. Dean, David K. Rea, T.L. Vallier, Charles Adelseck
1981, Initial Reports of the D.S.D.P. (62) 1073-1120
The Mid-Pacific Mountains constitute one of the largest aseismic rises in the central North Pacific Ocean. They have been generated by mid-plate volcanic events prior to Barremian time, but their volcanic activity continued through the remainder of the Cretaceous. Evidence of the latest stages of this volcanism are the trachytic...
The geology of Hess Rise, central north Pacific Ocean
T. L. Vallier, David K. Rea, Walter E. Dean, Jorn Thiede, Charles Adelseck
1981, Initial Reports of the D.S.D.P. (62) 1031-1072
The geology of Hess Rise is interpreted from studies of morphology and structure, igneous petrology, sediment lithofacies, seismic stratigraphy, and paleoenvironments. Hess Rise probably formed at a triple junction, between 116 and 95 m.y. ago, in the equatorial zone of the southern hemisphere. A large archipelago, formed by volcanism, subsequently...
Multichannel seismic evidence bearing on the origin of Bowers Ridge, Bering Sea
Alan K. Cooper, Michael S. Marlow, Z. Ben-Avraham
1981, GSA Bulletin (92) 474-484
Bowers Ridge is a large, arcuate sub-marine ridge that extends north and west from the Aleutian Ridge and separates the abyssal Aleutian and Bowers Basins in the Bering Sea. Two multichannel seismic-reflection lines recorded in 1976 over Bowers Ridge and the adjacent basins confirm the existence of 8- to 10-km-thick...
Early evolution of the Bering Sea by collision of oceanic rises and North Pacific subduction zones
Z. Ben-Avraham, Alan K. Cooper
1981, GSA Bulletin (92) 485-495
Three major bathymetric features exist in the Bering Sea: Shirshov Ridge, Bowers Ridge, and Umnak Plateau. New refraction data over Umnak Plateau and previous geophysical data across Bowers Ridge indicate that a thickened welt of crustal material is present beneath both features. The crustal structure is transitional between oceanic and...
Water resources data
Water Resources Division, U.S. Geological Survey
1981, Report, U.S. Geological Survey water-supply paper
No abstract available....
Water resources data
Water Resources Division, U.S. Geological Survey
1981, Report, U.S. Geological Survey water-supply paper
No abstract available....
Water resources data
Water Resources Division, U.S. Geological Survey
1981, Report, U.S. Geological Survey water-data report
No abstract available....
Water resources data
Water Resources Division, U.S. Geological Survey
1981, Report, U.S. Geological Survey water-supply paper
No abstract available....