Nonvolcanic Seafloor Spreading and Corner-Flow Rotation Accommodated by Extensional Faulting At 15 Degrees N on the Mid-Atlantic Ridge: A Structural Synthesis of ODP Leg 209
نویسندگان
چکیده
منابع مشابه
Nonvolcanic seafloor spreading and corner-flow rotation
[1] Drilling during ODP Leg 209, dredging, and submersible dives have delineated an anomalous stretch of the Mid-Atlantic Ridge north and south of the 15 200N Fracture Zone. The seafloor here consists dominantly of mantle peridotite with gabbroic intrusions that in places is covered by a thin, discontinuous extrusive volcanic layer. Thick lithosphere (10–20 km) in this region inhibits magma fro...
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This paper provides a summary of postcruise scientific results from Ocean Drilling Program (ODP) Leg 209 available to date, building upon shipboard observations and syntheses summarized in the Leg 209 Initial Results volume. During Leg 209, 19 holes were drilled at 8 sites along the Mid-Atlantic Ridge from 14°43′ to 15°44′N, mainly in residual mantle peridotite intruded by gabbroic rocks, in or...
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Leg 209 was devoted to drilling mantle peridotites and associated gabbroic rocks along the Mid-Atlantic Ridge from 14° to 16°N. This area was identified at the 1996 Workshop on Oceanic Lithosphere and Scientific Drilling into the 21st Century (OL Workshop) as the ideal region for drilling of a strike line of short holes to sample the upper mantle in a magma-starved portion of a slow-spreading r...
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In 1994, a joint Japanese-American dive program utilizing the worlds deepest diving active research submersible (SHINKAI 6500) was carried out at the western ridge-transform intersection (RTI) of the Mid-Atlantic Ridge and Kane transform in the central North Atlantic Ocean. A total of 15 dives were completed along with surface-ship geophysical mapping of bathymetry, magnetic and gravity fields....
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