Topography of Upper Mantle Discontinuities Beneath Nazca Plate and Its Surrounding Area Reveals from SS Precursor and Its Tectonic Significance

被引：0
|
作者：
Ma Y. [1 ]
Ge Z. [1 ]
机构：
[1] School of Earth and Space Sciences, Peking University, Beijing
来源：
Ge, Zengxi (zge@pku.edu.cn) | 2018年 / Peking University卷 / 54期
关键词：
Hotspot; Mantle transition zone; Slab; Southern East Pacific Rise; Upper mantle discontinuity;
D O I：
10.13209/j.0479-8023.2017.179
中图分类号：
学科分类号：
摘要：
An upper mantle discontinuity topography map of southern Nazca Plate and western South America Plate (120°W-60°W, 30°S-5°N) was obtained by using common mid-point stacking in bins of 5 degree radius over ten thousand USArray teleseismic records. The resolution was higher than that of previous studies because the records more densely sampled the region so that stacking bins were smaller. Discontinuity topography corresponding to high temperature anomalies in deep mantle was observed beneath Galapagos, Easter and San Felix hotspots. Other findings include a depression of 410 km discontinuity beneath Southern East Pacific Rise and depressions of both 410 km and 660 km discontinuities beneath the subduction zone. © 2018 Peking University.
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页码：1186 / 1194
页数：8
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