Geophysical Constraints on Recycling of Oceanic Lithosphere
The path of an oceanic slab as it subducts beneath a continent or ocean is generally illuminated by a plane of earthquakes. In most subduction zones the earthquake activity is probably confined to the upper tens of kilometers of the plate and also to depths less than about 680 km. However, despite the apparent rigidity suggested by the presence of earthquakes, recent studies have shown that the subducted lithosphere can contort without tearing and/or without substantial release of seismic energy (e.g., Schneider and Sacks, 1987, Hasegawa and Sacks, 1981). In addition, slabs can have significant aseismic extent. In many regions, therefore, the path of the slab or even its existence is not obvious.
KeywordssUbduction Zone Oceanic Slab High Heat Flow Intraplate Earthquake Cold Slab
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