| 南美地区下地幔速度界面结构研究 |
| |
| 引用本文： | 周元泽,眭怡.南美地区下地幔速度界面结构研究[J].地球物理学报,2010,53(1):86-93. |
| |
| 作者姓名： | 周元泽 眭怡 |
| |
| 作者单位： | 中国科学院研究生院计算地球动力学重点实验室，北京100049 |
| |
| 摘 要： | 下地幔间断面是地球内部结构研究的重要课题,对于理解地球深部的动力过程具有重要意义.美国西部密集地震台网记录到的南美洲太平洋地区深震的短周期波形资料有利于震源下方下地幔间断面的研究.本文收集了美国西北太平洋地震台网和犹他大学地震台网所记录的南美洲西部俯冲地区15个深震的19组短周期垂向台网资料,并利用4次根倾斜叠加方法提取震源下方下地幔中速度界面上发生转换的次生震相SdP,据此发现南美洲西部下方下地幔中800~1200 km深度范围内存在明显的转换点集中,主要分布在900,1000和1100 km三个深度附近,三个速度界面具有不同的起伏形态,应为在研究区域双层地幔对流中间边界层.
|
| 关 键 词： | 南美洲 下地幔间断面 N次根倾斜叠加 |
| 收稿时间： | 2009-06-04 |
| 修稿时间： | 2009-12-16 |
On the velocity interfaces in the lower mantle beneath South America |
| |
| ZHOU Yuan-Ze,SUI Yi.On the velocity interfaces in the lower mantle beneath South America[J].Chinese Journal of Geophysics,2010,53(1):86-93. |
| |
| Authors: | ZHOU Yuan-Ze SUI Yi |
| |
| Institution: | Lab of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, China |
| |
| Abstract: | The lower mantle discontinuities are an important part of the structure of Earth's interior and very important for understanding the dynamic process of the deep part of the Earth. The waveform data of the deep events of South America recorded by the dense stations at western part of USA are suitable for studying lower mantle discontinuities beneath the events. In the paper, 19 sets waveform data of vertical short period component from 15 events beneath South America recorded by the PNSN and UUSS of USA were retrieved and processed with 4-th root slant stack method for picking the SdP phases from the lower mantle interfaces. With the SdPs,the conversion points related to SdPs are found to be concentrated between 800 and 1200 km and mainly distribute at the depths of 900, 1000 and 1100 km. In addition, the topography of the three layers is different. The interfaces may relate to the mid-boundary of the two-layer mantle convection. |
| |
| Keywords: | South America Lower mantle discontinuities N-th root slant stack |
| 本文献已被 万方数据 等数据库收录！ |
| 点击此处可从《地球物理学报》浏览原始摘要信息 |
| 点击此处可从《地球物理学报》下载免费的PDF全文 |
|
