High-resolution image of the oceanic Moho in the subductirng Nazca plate from P-S converted waves

被引：37

作者：

Bock, G ^{[1
]}

Schurr, B ^{[1
]}

Asch, G ^{[1
]}

机构：

[1] Geoforschungszentrum Potsdam, D-14473 Potsdam, Germany

来源：

GEOPHYSICAL RESEARCH LETTERS | 2000年 / 27卷 / 23期

关键词：

D O I：

10.1029/2000GL011881

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Short-period P - S converted waves outline the oceanic Moho of the descending Nazca plate in northern Chile at 24 degreesS. Comparison with hypocentral locations obtained with temporary local seismic networks show that earthquakes inside the subducting oceanic lithosphere of the Nazca plate are located predominantly in the oceanic crust at depths between 70 and 120 km, and probably in the upper mantle at depths below 120 km. The results suggest that dehydration embrittlement as mechanism for intermediate-depth earthquakes is active both in the former oceanic crust and upper mantle of subducting lithosphere.

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页码：3929 / 3932

页数：4

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