Results 161 to 170 of about 26,760 (208)

On the spreading of the East Pacific Rise

Tectonophysics, 1990
Abstract We analyze through statistical methods the mechanics of the East Pacific Rise by considering the relative angular velocities of spreading of the Pacific-Nazca, Pacifie-Cocos and Pacific-Rivera margins. We focus our attention on verifying the validity of some issues such as the constancy of the velocity of spreading, the symmetry of the ...
Marzocchi, W., Mulargia, F.
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Tertiary Sediment from the East Pacific Rise

Science, 1967
More than 50 cores ranging in age from Pliocene to Lower Miocene have been recovered from the East Pacific Rise. Near the crestal regions the sediment cover is thin or lacking, and only Pleistocene sediments were recovered. On the flanks, the sediment thickness increases and pre-Pleistocene sediments are encountered.
L H, Burckle, J, Ewing, T, Saito, R, Leyden   +3 more
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Seismic Structure of the Southern East Pacific Rise

Science, 1993
Seismic data from the ultrafast-spreading (150 to 162 millimeters per year) southern East Pacific Rise show that the rise axis is underlain by a thin (less than 200 meters thick) extrusive volcanic layer (seismic layer 2A) that thickens rapidly off axis.
R S, Detrick, A J, Harding, G M, Kent, J A, Orcutt, J C, Mutter, P, Buhl   +5 more
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Hydrothermal Germanium Over the Southern East Pacific Rise

Science, 1986
Germanium enrichment in the oceanic water column above the southern axis of the East Pacific Rise results from hydrothermal solutions emanating from hot springs along the rise crest. This plume signature provides a new oceanic tracer of reactions between seawater and sea floor basalts during hydrothermal alteration.
R A, Mortlock, P N, Froelich
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Dynamics of a seafloor-spreading episode at the East Pacific Rise

Nature, 2016
Seafloor spreading is largely unobserved because 98 per cent of the global mid-ocean-ridge system is below the ocean surface. Our understanding of the dynamic processes that control seafloor spreading is thus inferred largely from geophysical observations of spreading events on land at Afar in East Africa and Iceland.
Yen Joe, Tan, Maya, Tolstoy, Felix, Waldhauser, William S D, Wilcock   +3 more
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East Pacific Rise: Hot Springs and Geophysical Experiments

Science, 1980
Hydrothermal vents jetting out water at 380° ± 30°C have been discovered on the axis of the East Pacific Rise. The hottest waters issue from mineralized chimneys and are blackened by sulfide precipitates. These hydrothermal springs are the sites of actively forming massive sulfide mineral deposits.
F N, Spiess, K C, Macdonald, T, Atwater, R, Ballard, A, Carranza, D, Cordoba, C, Cox, V M, Garcia, J, Francheteau, J, Guerrero, J, Hawkins, R, Haymon, R, Hessler, T, Juteau, M, Kastner, R, Larson, B, Luyendyk, J D, Macdougall, S, Miller, W, Normark, J, Orcutt, C, Rangin   +21 more
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Uranium Rich Sediments on the East Pacific Rise

Nature, 1969
SEDIMENTS on mid-ocean ridges associated with ocean floor spreading and high heat flow are poor in Al, Ti, Si, Cu, Co, Ni and rare earth elements, and enriched in Fe, Mn, V, Cd, Hg, As, B, Cr, Ba and P, compared with other pelagic sediments. The origin of these distribution patterns is not fully understood but is most likely the result of volcanic ...
DAVID E. FISHER, KURT BOSTROM
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The East Pacific Rise and the thermal model

Journal of Geophysical Research: Solid Earth, 1983
Although the thermal mode of lithosphere cooling can be used to predict the East Pacific Rise topography reasonably well, it does not adequately predict the observed gravity when the zero temperature boundary condition is at the seafloor. The misfit arises primarily because this model predicts thermally lowered densities in the crust at the rise axis ...
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Stauromedusae on the East Pacific Rise

2006
Dense aggregations of the large stauromedusae Lucernaria janetae Collins & Daly, 2005 are known from four sites near East Pacific Rise hydrothermal vents, but as is typical of circum-vent animals, their biology remains virtually unstudied. Observations of stauromedusae from near 8°36'N find that they are consistently near fissures from which warm,
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A seismic experiment at the axis of the East Pacific Rise

Marine Geology, 1980
Abstract Data from a seismic-refraction experiment on the East Pacific Rise at the mouth of the Gulf of California indicate that the axial valley in this area is underlain by low-velocity material (possibly a magma chamber) and, in addition, that the crust thickens rapidly away from the axis.
J.S. McClain, B.T.R. Lewis
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