Lg尾波Q_0值与中国大陆及邻区的地质构造关系  

Lg CODA Q_0 VALUE AND ITS RELATION WITH THE TECTONICS IN CHINESE MAINLAND AND ADJACENT REGIONS

作　　者：苏伟[1] 吴建平[1] 明跃红[1] 王椿镛[1] 

机构地区：[1]中国地震局地球物理研究所,中国北京100081

出　　处：《地震学报》2006年第2期132-140,共9页Acta Seismologica Sinica

基　　金：中国大陆数字壳幔结构项目;地震科学联合基金(104060)资助

摘　　要：利用中国大陆45个宽频带数字地震台站的432条垂直向地震记录，采用叠加频谱比值法计算单台Lg尾波Q0（1Hz的Q值）及η值．利用层析成像方法反演得到中国大陆及邻区（70°～135°E，20°～50°N）Lg尾波Q及η值的横向变化图象．结果表明，中国大陆及邻区Q0值主要在150～600之间．其中川滇及缅甸西北部地区的Q0值最低（〈240）．该地区地壳有复杂的断裂破碎构造及强烈的水热活动．最高Q0值（Q0〉510）区主要位于蒙古高原南部、阿拉善、鄂尔多斯块体交界．其频率依赖η值在0．45～0．75之间变化．We have collected 432 vertical component records from 45 stations of new CENC （China Earthquake Network Center） in Chinese mainland and adjacent regions. These records were used to calculate Q0 （Q at 1 Hz） and ηvalues of Lg coda from each station by the stack spectral ratio method. Then the tomography method was applied to obtaining lateral variation of Q0 and ηvalues in Chinese mainland and adjacent regions. The result indicates that Q0 value varies between 150 and 600 in the studied areas. Yunnan, southwest Sichuan, and northwest Myanmar show the lowest Q0 value（Q0〈240） and the crust of these regions is characterized by complicated crack and strong hydrothermal activity. The highest Q0 value （Q0〉510） exists in the border of southern Mongolia, Alxa and Ordos block. The ηvalue varies between 0.45 and 0.75 in Chinese mainland and its adjacent regions.

关 键 词：中国大陆及邻区 LG尾波 Q0值 η值 

分 类 号：P315.31[天文地球—地震学]