地震学报2012，Vol.34Issue(2)：137-146,10.DOI:10.3969/j.issn.0253-3782.2012.02.002
东北地区660km间断面附近波速结构研究
Detecting velocity structure around 660-km discontinuity beneath Northeastern China
摘要
Abstract
Located at the front edge of the Wadati-Benioff zone of subducted northwestern Pacific plate, the velocity structure in the mantle transition zone beneath Northeastern China plays an important role in constraining the behavior of subducted slabs and material or energy exchange in mantle. By modeling P and SH triplicate waveforms from two deep events, recorded by a dense regional network stations, we show that a layer of fast anomaly, about 130 km thick, lies above the 660-km discontinuity with slight depression, which may be associated with the westward extension of the stagnant Pacific slab. The mantle transition zone, as a whole, is featured by low shear wave velocity and high vP/ vS ratio, which may indicate the existence of a water-bearing mantle transition zone.关键词
三重震相/660 km间断面/俯冲板块/S波低速异常/东北地区Key words
triplication/ 660-km discontinuity/ subducted slab/ low shear velocity anomaly/ Northeastern China分类
天文与地球科学引用本文复制引用
叶玲玲,李娟..东北地区660km间断面附近波速结构研究[J].地震学报,2012,34(2):137-146,10.基金项目
国家自然科学基金项目(41074034,40774042和90714012)资助. （41074034,40774042和90714012）
