Publications
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Silver and other tracers of sewage particles in coastal and deep sea sediments off the east coast, USA
No abstract available.
Authors
Michael H. Bothner, Marilyn R. Buchholtz ten Brink, G.E. Ravizza
The impacts of mobile fishing gear on low topography benthic habitats in the Gulf of Maine (Northwest Atlantic): A preliminary report
No abstract available.
Authors
Peter J. Auster, Richard J. Malatesta, Richard W. Langton, Les Watling, Andrew N. Shepard, Ivar G. Babb
Decadal and annual changes in biogenic opal and carbonate fluxes to the deep Sargasso Sea
Analyses of samples from a 14-year series of sediment-trap deployments in the deep Sargasso Sea reveal a significant trend in the ratio of the sinking fluxes of biogenic calcium carbonate and silica. Although there are pronounced seasonal cycles for both flux components, the overall opal/CaCO3 ratio changed by 50% from 1978 to 1991 (largely due to a decrease of opal flux), while total flux had no
Authors
W.G. Deuser, T.D. Jickells, Judith A. Commeau
Geological mapping of biological habitats on Georges Bank and Stellwaen Bank, Gulf of Maine region
No abstract available.
Authors
Page C. Valentine, Eric A. Schmuck
Pulling the rug out from under California: Seismic images of the Mendocino Triple Junction region
The active tectonic regime of northwestern California changes abruptly from transform motion to subduction at the Mendocino Triple Junction. Northward migration of the triple junction has been a major factor in the tectonic history of the continental margin of California since the Oligocene and continues at present. Understanding the effects of triple junction migration on the structure of the cru
Authors
Anne M. Tréhu
Radiocarbon ages of pre-bomb clams and the hard-water effect in Lakes Michigan and Huron
Five radiocarbon ages, all determined by accelerator mass spectrometry, have been obtained for two pre-bomb bivalves from Lake Michigan and one from Lake Huron. After correcting those ages for the fractionation of14C in calcite and for the radioactively inert CO2 in the atmosphere, we find residual ages, caused by the hard water effect, of about 250 years for Lake Michigan and 440 years for Lake H
Authors
David K. Rea, Steven M. Colman
Nonperiodic eddy pulsations
Recirculating flow in lateral separation eddies is typically weaker than main stem flow and provides an effective environment for trapping sediment. Observations of recirculating flow and sedimentary structures demonstrate that eddies pulsate in size and in flow velocity even when main stem flow is steady. Time series measurements of flow velocity and location of the reattachment point indicate th
Authors
David M. Rubin, Richard R. McDonald
Stratigraphic and palaeoenvironmental summary of the south-east Georgia embayment: a correlation of exploratory wells
A Continental Offshore Stratigraphic Test (COST) well and six exploratory wells have been drilled in the south-east Georgia embayment. The oldest rocks penetrated are weakly metamorphosed Lower Ordovician quartz arenites and Silurian shales and argillites in the Transco 1005-1 well and Upper Devonian argillites in the COST GE-1 well. These marine strata, which are equivalent to the Tippecanoe sequ
Authors
Lawrence J. Poppe, Peter Popenoe, C. Wylie Poag, B. Ann Swift
Velocities of southern Basin and Range xenoliths: Insights on the nature of lower crustal reflectivity and composition
To reconcile differences between the assessments of crustal composition in the southern Basin and Range province on the basis of seismic refraction and reflection data and lower-crustal xenoliths, we measured velocities of xenoliths from the Cima volcanic field in southern California. Lower-crustal samples studied included gabbro, microgabbro, and pyroxenite. We find that the mafic xenolith veloci
Authors
Thomas E. Parsons, Nikolas I. Christensen, Howard G. Wilshire
Rift flank segmentation, basin initiation and propagation: a neotectonic example from Lake Baikal
New surficial data (field, Landsat TM and topography) define morpho-tectonic domains and rift flank segmentation in the Ol'khon region of the Central Baikal rift. Deformation, drainage and depositional patterns indicate a change in the locus of active extension that may relate to a recent (<l Ma) change in the kinematics of the Siberian plate boundary. The westwards migration of the border fault l
Authors
Susan M. Agar, Kim D. Klitgord