塔里木盆地岩石高温高压下波速的实验研究及其地质意义  

Experimental Study on Wave Velocity of Rocks from Tarim Basin at High PT Conditions and Its Geological Implications

作　　者：李华[1] 王良书[1] 李成[1] 刘绍文[1] 

机构地区：[1]南京大学地球科学系,南京210093

出　　处：《高校地质学报》2005年第4期601-607,共7页Geological Journal of China Universities

基　　金：国家自然科学基金项目(项目批准号:40072066)教育部博士点基金(2000028427)

摘　　要：给出了塔里木盆地多种岩石样品在高温高压下弹性波纵波波速(Vp)的实验室测量结果。在最大压力为2 GPa,常温下样品的Vp范围从6．007-6．803 km·s-1时,最大值为安山质火山碎屑岩;当温度为600℃,Vp范围从 5．871-6．658 km·s-1时,其最大值是安山岩。结合地震转换波速度结构等资料,分析认为塔里木盆地地壳结构在大部分地区可三分:上地壳为花岗质变质岩为主;中地壳以花岗闪长岩为特征;下地壳是以安山玄武质成分为特征的岩层。The results of experimental measurements on elastic wave velocity （Vp） for rocks of different types from Tarim Basin at high temperatures and high pressures are presented here. The Vp of samples at ordinary temperature ranges from 6.007 km·s^-1 to 6.803km·s^-1, given the maximum pressure at 2.0 GPa, and the andesitic volcanoclastic rock has the largest Vp. At the temperature of 600℃, the Vp varies between 5. 871 km·s^-1 and 6.658 km·s^-1, and the largest Vp value is obtained also for andesite. Combined with the velocity structure derived from seismic converted wave in study area, here we propose that the crustal structure in the most areas of Tarim Basin is of three layers ： the upper crust consists mainly of granitic metamorphic rocks, the middle crust is mainly made of granitic diorite, and the lower crust is mainly composed of andesitic basalts.

关 键 词：塔里木盆地 高温高压 波速 地壳成分 地壳结构 

分 类 号：P315.9[天文地球—地震学]