论文部分内容阅读
利用中国东北长白山附近的19个临时地震台站和中国数字化地震台网的3个台站所记录到的高精度远震P波到时资料, 对长白山及邻近地区的地壳上地幔三维速度结构进行了详细研究. 结果表明, 长白山火山区的地壳上地幔中存在显著的低速异常, 而且该低速异常深达400 km左右、宽约200 km; 在地幔转换带及下地幔中存在高速异常. 这一结构特征与全球地震层析成像结果相同. 本文认为, 长白山火山并非如夏威夷那样的板内热点火山, 而是与太平洋板块的深俯冲及其在东亚地幔转换带中的滞留、脱水等过程密切相关的一种弧后板内火山.
Using the high-precision teleseismic P-wave arrival data recorded by 19 temporary earth stations near Changbai Mountain in Northeast China and 3 stations at China Digital Seismic Network, the 3D velocity structure of the crust and upper mantle in Changbai Mountain and its adjacent areas The results show that there is a significant low-velocity anomaly in the crust and upper mantle in the Changbai Mountain volcanic region, and the low-velocity anomaly is about 400 km deep and about 200 km wide. There are high-velocity anomalies in the mantle transition zone and the lower mantle The structural features are the same as the results of global seismic tomography.The paper suggests that the Changbai Mountain volcano is not an intraplate hot volcano in Hawaii but is closely related to the deep subduction of the Pacific plate and its retention and dehydration in the East Asia mantle transition zone A kind of back arc plate inside the volcano.