Publications
Scientific reports, journal articles, and information products produced by USGS Pacific Coastal and Marine Science Center scientists.
Filter Total Items: 1336
Hydrocarbon gases in sediment of the Voring Plateau, Norwegian Sea
Geochemical studies at three ODP Leg 104 sites on the Wring Plateau help define the distribution of hydrocarbon gases in sediment of this prominent feature of the Norwegian continental margin. Low levels of hydrocarbon gas were encountered in sediment of the outer part of the plateau, but sediment of the inner part of the plateau is very gassy. The molecular composition of inner plateau gases ( >
Authors
Keith A. Kvenvolden, Margaret Golan-Bac, T.J. McDonald, R.C. Pflaum, J.M. Brooks
Organic matter at sites 642, 643, and 644, ODP Leg 104
Sedimentary extractable organic matter was analyzed at three ODP Leg 104 sites in the Norwegian Sea. Organic carbon content ranged from less than 0.1% to a maximum of 1.8%. Extractable organic matter content and unresolved complex mixture concentrations were low and randomly distributed. Low levels of aliphatic (branched and normal) and aromatic hydrocarbons were detected in all of the sediments a
Authors
T.J. McDonald, M.C. Kennicutt, J.M. Brooks, Keith A. Kvenvolden
Organic geochemistry on Leg 104
The Leg 104 organic geochemistry program consisted of monitoring (a) hydrocarbon gases, (b) organic and inorganic carbon, and (c) parameters resulting from Rock-Eval pyrolysis at three sites on the Vdring Plateau. The results amplify some of those obtained earlier on Deep Sea Drilling Project (DSDP) Leg 38. In a regional sense there is an inverse correlation between amounts of hydrocarbon gas and
Authors
Keith A. Kvenvolden, T.J. McDonald
Marine magnetic gradiometer: A tool for the seismic interpreter
The marine magnetometer has been used since the early '50s as an ancillary tool on vessels conducting regional and local seismic surveys. Emphasis on marine magnetic data by academia has led to major discoveries about the structure of the earth's crust, such as the association of shallow, crustal magnetic anomalies to seafloor spreading and long-wavelength anomalies to deep crustal origin. The sam
Authors
Richard J. Wold, Alan K. Cooper
Observations in Monterey Canyon and Fan Valley using the submersible Alvin and a photographic sled
No abstract available.
Authors
Stephen L. Eittreim, R.W. Embley, W. R. Normark, H. Gary Greene, C.M. McHugh, W.B. Ryan
Morphodynamic signature of the 1985 hurricane impacts on the northern Gulf of Mexico
Three hurricanes hit Lousiana (LA), Mississippi (MS), Alabama (AL), and the Florida (FL) panhandle in 1985, producing dramatic geomorphic changes in a wide variety of coastal environments. The impact zone for hurricanes Danny, Elena, and Juan stretched 1000 km between the Sabine River in LA to the Apalachicola River in FL. Barrier shorelines experienced repeated intense overwash events, producing
Authors
Shea Penland, John R. Suter, Ashbury H. Sallenger, S. Jeffress Williams, Randolph A. McBride, Karen E. Westphal, P. Douglas Reimer, Bruce E. Jaffe
Morphology and growth history of Delgada Fan: Implications for the Neogene evolution of Point Arena Basin and the Mendocino Triple Junction
Long-range side scan (GLORIA) sonographs and seismic reflection data acquired during a survey of the western U.S. Exclusive Economic Zone in 1984, coupled with information from Deep Sea Drilling Project sites, provide new insights into the growth and evolution of the Delgada Fan. Construction of the fan commenced in the latest Miocene (∼6 Ma) following the filling of the Neogene Point Arena Basin.
Authors
D. E. Drake, D. A. Cacchione, J.V. Gardner, D. S. McCulloch, D. Masson
Comment and reply on "Bacterially mediated diagenetic origin for chert-hosted manganese deposits in the Franciscan Complex, California Coast Ranges"
No abstract available.
Authors
Loren A. Raymond, James R. Hein, Randolph A. Koski
Physiography of the western United States Exclusive Economic Zone
GLORIA (Geologic Long-Range Inclined Asdic) sidescan sonar images were collected over the entire Exclusive Economic Zone (EEZ) west of the conterminous United States. The continuous, overlapping, swath-mapping technique provides, for the first time, a reconnaissance plan view off the entire sea floor from the edge of the continental shelf to 370 km from shore. The mid-ocean ridges, transform fault
Authors
D. A. Cacchione, D. E. Drake, Brian D. Edwards, M. E. Field, J. V. Gardner, M. A. Hampton, H. A. Karl, N.H. Kenyon, D.G. Masson, David S. McCulloch
The laboratory albitization of mid-ocean ridge basalt
Complete alteration of fresh mid-ocean ridge basalt to albite + actinolite + smectite took place in the presence of quartz and 3.4m NaCl at 350°C and 400 bars. Significant Na-metasomatism occurred in exchange for Ca + Fe + Mn. In contrast, alteration of the basalt/quartz mixture with a synthetically prepared "natural brine," and basalt with 3.4m NaCl or "natural brine" did not produce significant
Authors
Robert J. Rosenbauer, James L. Bischoff, Robert A. Zierenberg
Amino-acid diagenesis and its implication for late Pleistocene lacustrine sediment, Clear Lake, California
The diagenesis of amino acids in sediments from Clear Lake core CL-80-1 is indicated by changes in amino acid concentrations, compositions, and stereochemistry. Concentrations of total amino acids decrease with depth, but the decrease is not systematic, possibly reflecting a nonuniformity in sedimentary and postdepositional processes affecting the amino acids. Ratios of neutral/acidic amino acids
Authors
D.J. Blunt, Keith A. Kvenvolden
Methane hydrates and global climate
Methane hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. The amount of methane sequestered in gas hydrates is probably enormous, but estimates of the amounts are speculative and range over three orders of magnitude (about 103 to 106 GT (gigatons = 1015 g)). A question of current interest concerns the possible consequences of an ad
Authors
Keith A. Kvenvolden