Results 181 to 190 of about 1,849 (215)

Hydrological response to a seafloor spreading episode on the Juan de Fuca ridge

Nature, 2004
Seafloor hydrothermal systems are known to respond to seismic and magmatic activity along mid-ocean ridges, often resulting in locally positive changes in hydrothermal discharge rate, temperature and microbial activity, and shifts in composition occurring at the time of earthquake swarms and axial crustal dike injections. Corresponding regional effects
Earl, Davis, Keir, Becker, Robert, Dziak, John, Cassidy, Kelin, Wang, Marvin, Lilley   +5 more
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Introduction to Juan de Fuca Ridge Special Section

Journal of Geophysical Research: Solid Earth, 1987
The U.S. Geological Survey and several other institutions have been studying the southernmost segment of the Juan de Fuca Ridge for several years by almost every means available to marine geologists and geophysicists [e.g., Normark et al., this issue].
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Magnetic structure of the Juan de Fuca-Gorda Ridge Area

Journal of Geophysical Research, 1969
By using the fracture pattern deduced by N. Pavoni (1966) with a different interpretation of the magnetic anomaly lineations, a reconstruction can be made in which the Juan de Fuca and Gorda ridges form a single, continuous, north-south trending feature. From this reconstruction, the present magnetic structural pattern can be derived by (1) development
George Peter, Robert Lattimore
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A microseismicity survey of Axial Seamount, Juan de Fuca Ridge

Bulletin of the Seismological Society of America, 1987
Abstract An array of ocean bottom seismometers and hydrophones were deployed within the caldera of Axial Seamount, located at the intersection of the Cobb-Eickelberg Seamount Chain and the Juan de Fuca Ridge. Recent manned submersible dives have discovered the presence of two distinct hydrothermal vent fields.
R. S. Jacobson, L. D. Bibee, R. W. Embley, S. R. Hammond   +3 more
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The magnetic structure of Axial Seamount, Juan de Fuca Ridge

Journal of Geophysical Research: Solid Earth, 1990
Axial Seamount is a large, volcanically active seamount located in the eastern Pacific on the central Juan de Fuca (JDF) ridge at 46°N, 130′W. Sea surface magnetic anomaly data show that Axial lies completely within crust formed during the Brunhes normal polarity epoch.
Maurice A. Tivey, H. Paul Johnson
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Seafloor Positioning Across Juan De Fuca Ridge

1994
Abstract : The results of an analysis of a complex data set acquired during the United States Geological Survey's Marine Crustal Deformation Study are presented. The experiment, which commenced in the spring of 1992 in a region of the Pacific known as the Juan de Fuca ridge, represents a first attempt to locally monitor plate dynamics in the marine ...
Fell, Patrick, Seay, C. Harris
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Mercury Thermoforms and Their Distribution in the Sedimentary Sequence of the Juan De Fuca Ridge

Geochemistry International, 2020
This paper addresses the vertical distribution of total mercury and its thermoforms in the Holocene–Upper Pleistocene sedimentary rocks from the Dead Dog active hydrothermal field in the Middle Valley, Juan de Fuca Ridge, Pacific Ocean. Sediment samples were taken from the core of Hole 858B drilled during ODP leg on the top of a sulfide hill, in a zone
L. N. Luchsheva, V. B. Kurnosov, Yu. I. Konovalov   +2 more
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Heat flow west of the Juan de Fuca Ridge

Journal of Geophysical Research, 1970
Fifteen new heat-flow measurements have been made as part of a general geophysical study west of the Juan de Fuca ridge. All but one are within 16 km of latitude 47°N, and they form a profile from the crest of the ridge to a point out on the Tufts abyssal plain.
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Structure of the Northern Symmetrical Segment of the Juan de Fuca Ridge

Marine Geophysical Researches, 1993
A seismic refraction profile was shot along the axis of the Northern Symmetrical Segment of the Juan de Fuca Ridge system. Three models of the along-axis crustal structure fit the observed data equally well. One model includes a low-velocity zone, the top of which is at a depth below the seafloor of approximately 3 km, that is continuous along-axis for
G. L. Christeson, G. M. Purdy, K. M. M. Rohr   +2 more
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Water column hydrothermal plumes on the Juan de Fuca Ridge

Journal of Geophysical Research: Solid Earth, 1990
Hydrographic surveys on the Juan de Fuca Ridge (JdFR) carried out from 1980 to 1987 show a complex pattern of 3He and Mn‐rich water column plumes produced by venting from several submarine hot spring areas. In the vicinity of Axial Volcano at latitude 46°N, distinct plumes were detected in 1980, 1982, and 1983 with3He signatures up to δ(3He) = 64% at ...
openaire   +1 more source