俯冲带主要含水矿物弹性波性质研究现状及展望  

Research status and prospect of elastic wave properties of main hydrous minerals in subduction zone

作　　者：曾欢 马麦宁 张佳蕾 张璘翼 ZENG Huan;MA MaiNing;ZHANG JiaLei;ZHANG LinYi(Key Laboratory of Computational Geodynamics,College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]计算地球动力学重点实验室,中国科学院大学地球与行星科学学院,北京100049

出　　处：《地球物理学进展》2023年第4期1531-1542,共12页Progress in Geophysics

基　　金：国家自然科学基金(42174114,41674089)共同资助。

摘　　要：俯冲带中的含水矿物对物质循环和水迁移等有着极其重要的作用,同时也是俯冲带中的地震波速异常的主要原因.本文总结了近20年来,国内外对俯冲带三种主要含水硅酸盐矿物(蛇纹石、绿泥石和角闪石)弹性波速研究取得的重要成果:含水矿物普遍具有低波速、高各向异性的特点;压力增加波速增加,但波速各向异性降低.富含水矿物的岩石,波速各向异性随着含水矿物含量的增加而增大,同时受到含水矿物晶格择优取向(LPO)类型以及岩体中裂隙的影响.含水矿物LPO引起的地震波速各向异性特征与俯冲的角度有关,在低角度的俯冲带中会引起垂直于海沟方向的快速传播,而在高角度的俯冲带中引起平行于海沟方向的快速传播.文章最后针对目前俯冲带中含水矿物弹性波速研究中存在的问题,提出了未来需要在三个方面加强研究.The hydrous minerals in the subduction zone play an extremely important role in material circulation and water migration,and also control the abnormal seismic wave velocity in the subduction zone.This paper reviews the significant research progress in the study of elastic wave velocity of three main hydrous silicate minerals(serpentine,chlorite and hornblende)in the subduction zone in the past 20 years:hydrous minerals have the characteristics of low elastic wave velocity and high anisotropy;the increase of pressure induces the increase of elastic wave velocity and the decrease of anisotropy,while the increase of temperature leads to the decrease of the velocity.The anisotropy of elastic wave velocity of the rock rich in hydrous minerals increases with the increase of the hydrous mineral content,and is also affected by the type of Lattice Preferred Orientation(LPO)and cracks in the rock mass.The characteristics of seismic wave velocity anisotropy caused by the LPO of hydrous minerals are related to the angle of subduction.Rapid propagation perpendicular to the trench is induced in low-angle subduction zones,and parallel to the trench direction in high-angle subduction zones.At the end of the paper,the future research is suggested in the view of the problems existing in the current research.

关 键 词：俯冲带 含水矿物 高温高压 弹性波速 各向异性 

分 类 号：P315[天文地球—地震学]