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

@article{Macdonald1983OverlappingSC,
  title={Overlapping spreading centres: new accretion geometry on the East Pacific Rise},
  author={Ken C. Macdonald and Paul J. Fox},
  journal={Nature},
  year={1983},
  volume={302},
  pages={55-58}
}
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

Overlapping spreading centers (OSCs) are a type of ridge axis discontinuity found along intermediate and fast spreading centers. The ridges at these locations overlap and curve towards each other.

Overlapping rift zones at the 5.5°S offset of the East Pacific Rise

A Seabeam and magnetometer survey of the Pacific-Nazca plate boundary around 5.5°S mapped a “nontransform offset” whose geology and kinematics seem typical of a whole class of structures formed where

Overlapping spreading centres: 3-D inversion of the magnetic field at 9°03′N on the East Pacific Rise

Summary. Overlapping spreading centres (OSCs) represent a new type of plate boundary interaction in which en echelon rise segments overlap significantly and are not joined by a transform fault.

Deep‐tow studies of the overlapping spreading centers at 9°03′N on the East Pacific Rise

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

The morphology of propagating spreading centers: New and old

Recent Seabeam investigations over the East Pacific Rise in the northeast Pacific have shown the existence of a propagating spreading center at 18°N. The propagating and dying spreading centers are

Rifting of old oceanic lithosphere

Geophysical data from five regions in the Pacific and Indian oceans reveal that long distance (>400 km) spreading center jumps have occurred in the past. The present-day seafloor morphology is used
...

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