用接收函数叠加技术研究滇西上地幔间断面埋深*
夏静瑜,杨海燕,胡家富

(云南大学 地球物理系,昆明 650091)

接收函数; 动校正; 叠加; 间断面; 滇西

Depths of Discontinuity Surfaces in Crust and Upper Mantle beneath West Yunnan Determined by Stacking Receiver Function
XIA Jing-yu, YANG Hai-yan, HU Jia-fu

(Department of Geophysics, Yunnan University, Kunming 650091, Yunnan, China)

receiver function; normal moveout correction; stacking; surface of discontinuity; West Yunnan

备注

在对台站下方的径向接收函数进行分析和对比的基础上,通过基于动校正的接收函数叠加方法,利用云南数字地震台网记录的保山、畹町、沧源和腾冲4个台站的三分量宽频数据,计算出了各台站下方的SV分量接收函数。结果 表明,在保山、畹町和沧源台下方清楚地显示出了深度700 km处的间断面,较全球平均660 km要深。另外,在深度290～500 km之间可能还存在多个间断面; 腾冲台下方700 km处的间断面不太清楚,而且上地幔间断面仅为210 km深,较其它三个台要浅。

Through introducing the moveout correction technique in exploration seismology, we obtained a method to compute the receiver function beneath a station by stacking receiver function after normal moveout correction. We used the method to determine the SV-component receiver functions from 3-component broad-band digital recordings which were recorded by the Baoshan, Wanding, Cangyuan, Tengchong stations. The results show that, at the Baoshan, Wanding, Cangyuan stations, the depth of discontinuity is 700 km and it is deeper than the average of 660 km over the globe, meanwhile, there may be existed several discontinuities between 290 km and 500 km; however, the discontinuity beneath the Tengchong station is not clear at the depth of 700 km, and the depth of discontinuity in upper mantle is only 210 km, shallower than that beneath other 3 stations.