Publications
Filter Total Items: 1440
Carbonate and organic-carbon cycles and the history of upwelling at Deep Sea Drilling Project Site 532, Walvis Ridge, South Atlantic Ocean Carbonate and organic-carbon cycles and the history of upwelling at Deep Sea Drilling Project Site 532, Walvis Ridge, South Atlantic Ocean
Detailed carbonate and organic-carbon stratigraphies were constructed from samples collected every 20 cm in a 250-m hydraulic piston core recovered at DSDP Site 532 on Walvis Ridge. This sampling interval represents about one sample every 5000 yr., based on sediment accumulation rates calculated from nannofossil biostratigraphic zones. All samples were analyzed for percent CaCO3...
Authors
J. Gardner, Walter E. Dean, C.R. Wilson
Middle Cretaceous black shales at Site 530 in the southeastern Angola Basin Middle Cretaceous black shales at Site 530 in the southeastern Angola Basin
The middle Cretaceous black shale interval at Site 530 is 170 m thick and late Albian to Coniacian in age. The organic-carbon-rich sediments occur as 260 separate beds (average 4 cm, maximum 60 cm thick) and make up less than 10% of the recovered section. Associated lithologies are greenish, grayish, and reddish mudstones, marlstones, and rare limestones. Organic-carbon contents of the...
Authors
D.A. Stow, Walter E. Dean
Shimada Seamount: An example of recent mid-plate volcanism Shimada Seamount: An example of recent mid-plate volcanism
Shimada Seamount is an isolated volcanic feature located between the Clipperton and Clarion Fracture Zones ∼1,150 km west of the East Pacific Rise and ∼600 km west of the inactive spreading center represented by the Mathematician Seamounts. It rises ∼3,900 m above the surrounding sea floor to within 50 m of present-day sea level. The area of Shimada Seamount should be volcanically...
Authors
J. V. Gardner, Walter E. Dean, Richard J. Blakely
Models for the deposition of Mesozoic-Cenozoic fine-grained organic-carbon-rich sediment in the deep sea Models for the deposition of Mesozoic-Cenozoic fine-grained organic-carbon-rich sediment in the deep sea
The widespread occurrence of organic-carbon-rich strata (‘black shales’) in certain portions of Jurassic, Cretaceous and Cenozoic sequences has been well-documented from Deep Sea Drilling Project sites in the Atlantic and Pacific Oceans and from sequences, now exposed on land, originally deposited in the Tethyan ocean. These ancient black shales usually have been explained by analogy...
Authors
M.A. Arthur, Walter E. Dean, D.A.V. Stow
Opening of the Red Sea: Constraints from a palaeomagnetic study of the As Sarat volcanic field, south‐western Saudi Arabia Opening of the Red Sea: Constraints from a palaeomagnetic study of the As Sarat volcanic field, south‐western Saudi Arabia
Four stratigraphic sections through alkali basalt flows of Oligocene to Miocene age (29‐24 Ma) in the As Sarat volcanic field, south‐western Saudi Arabia, were sampled for palaeomagnetic study. After systematic alternating‐field demagnetization, 42 magnetically acceptable flows (139 samples) yield a mean direction of magnetization of =355.3°, =15.2° (α=4.3°), which defines a...
Authors
Karl S. Kellogg, R. L. Reynolds
Rhythmic bedding in Mesozoic- Cenozoic pelagic carbonate sequences: The primary and diagenetic origin of Milankovitch-like cycles Rhythmic bedding in Mesozoic- Cenozoic pelagic carbonate sequences: The primary and diagenetic origin of Milankovitch-like cycles
No abstract available.
Authors
M.A. Arthur, Walter E. Dean, D.J. Bottjer, Peter A. Scholle
Organic Geochemistry of Sediments Recovered by DSDP/IPOD Leg 75 from under the Benguela Current Organic Geochemistry of Sediments Recovered by DSDP/IPOD Leg 75 from under the Benguela Current
No abstract available.
Authors
P.A. Meyers, S. Brassell, A.Y. Huc, E.J. Barron, R.E. Boyce, Walter E. Dean, W.W. Hayes, Barbara H. Keating, C.L. McNulty, R.E. Schallreuter, Jean-Claude Sibuet, J.C. Steinmetz, D.A.V. Stow, Herbert Stradner
The Late Wisconsin glacial record of the Laurentide ice sheet in the United States The Late Wisconsin glacial record of the Laurentide ice sheet in the United States
No abstract available.
Authors
D.M. Mickelson, Lee Clayton, David S. Fullerton, H.W. Borns
Geologic evolution of Hess Rise, central North Pacific Ocean Geologic evolution of Hess Rise, central North Pacific Ocean
Cores from four Deep Sea Drilling Project (DSDP) sites (310, 464, 465, and 466) and seismic-reflection profiles provide data that are used to interpret the geological evolution and paleoenvironments of Hess Rise, a prominent oceanic plateau in the central North Pacific Ocean. Hess Rise apparently formed in the Southern Hemisphere along the western flank of the Pacific-Farallon Ridge 110...
Authors
T. L. Vallier, Walter E. Dean, David K. Rea, Jorn Thiede
The chemical composition of lakes in the north‐central United States The chemical composition of lakes in the north‐central United States
Lake waters of the north‐central U.S.A. are classified into five groups, based on increasing specific conductivity and changes in ionic composition from east to west, from Wisconsin through Minnesota to North and South Dakota. The most dilute group of waters has specific conductivities
Authors
Eville Gorham, Walter E. Dean, J.E. Sanger
U-Pb ages of uranium ores in the Churchrock uranium district, New Mexico U-Pb ages of uranium ores in the Churchrock uranium district, New Mexico
No abstract available.
Authors
K.R. Ludwig, Bruce Rubin, Neil Fishman, Richard L. Reynolds