Overlapping spreading centres: new accretion geometry on the East Pacific Rise

  title={Overlapping spreading centres: new accretion geometry on the East Pacific Rise},
  author={Ken C. Macdonald and Paul J. Fox},
In a detailed Seabeam investigation of the East Pacific Rise (EPR) from 8°N to 18°N, a new kind of volcano-tectonic geometry associated with fast-spreading centres has been discovered (Figs 1, 2). At several locations along the rise axis the neovolcanic zone is discontinuous, and is laterally offset a short distance (1–15 km). In contrast to a classic ridge–transform–ridge plate boundary, however, the offset ridge terminations overlap each other by a distance approximately equal to or greater… 

Fine scale study of a small overlapping spreading center system at 12°54′ N on the East Pacific Rise

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The deeply-towed instrument package of the Scripps Institution of Oceanography was used to study for the first time the fine scale structure of an overlapping spreading center (OSC) system: the

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A deeply-towed instrument package was used in a detailed survey of the crest of the East Pacific Rise (EPR) near 3°25′S, where the Pacific and Nazca plates are separating at 152 mm/yr. A single 90

Northern East Pacific Rise' Magnetic Anomaly and Bathymetric Framework

The oceanic crust in the eastern Pacific between 7oN and 30oN and east of 127oW contains a fairly complete history of the spreading centers associated with the East Pacific Rise since 25 m.y.B.P.

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A first order model of spreading centers as idealized linear boundaries of crustal and lithospheric generation provides only a gross understanding of global scale plate kinematics. As we attempt to

Evolution of oceanic crust: 2. Constraints, implications, and inferences

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Summary Three seismic refraction profiles have been recorded on the East Pacific Rise near the Siqueiros fracture zone. These profiles have been interpreted using both travel-time analysis and

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A submersible study has been conducted in February–March 1978 at the axis of the East Pacific Rise near 21°N. The expedition CYAMEX, the first submersible program to be conducted on the East Pacific