华南大陆东部壳幔结构的宽频带地震学探测

华南大陆是新元古代以来全球地质演化历史最复杂的地区之一, 也是欧亚板块东南缘地壳生长和大陆增生最活跃, 大规模构造变形、岩浆活动和多金属矿产资源最丰富的地区。揭示该区浅表构造与岩浆活动和成矿作用机制离不开对深部壳幔结构的研究。宽频带地震学是开展深部壳幔结构探测的重要手段, 基于宽频带地震学数据可以刻画地壳-岩石圈-上地幔-地幔过渡带不同深度和尺度的深部结构, 为深入理解研究区的深部构造、动力学过程、岩浆活动与成矿作用提供有效约束。本文较全面地总结了近二十年来在华南大陆东部地区开展的宽频带流动地震探测工作, 并对研究区的地壳厚度、Vp/Vs比值、岩石圈底界(LAB)深度、上地幔速度结构与各向异性等进行了分析与讨论。本文旨在为相关研究人员和团队提供未来在该区新布设地震探测台站时的参考, 也可为后续深入研究该区的深部结构与成矿过程提供一些深部要素约束。

Broad-band Seismic Study of the Crustal and Upper Mantle Structure in the Eastern South China Block

South China is one of the most geologically complex areas in eastern Asia, as it has undergone a long-period of crustal accretion and tectonic deformation since the Neo-Proterozoic. In addition, it has abundant magmatism activities and mineralization. To reveal the geodynamic process, mechanism of the sub-surface deformation, and the accompanying magmatism activities and mineralization, we needed more detailed information on the architecture and medium properties of the crust, lithosphere, and upper mantle. A broad-band seismic study could provide abundant information on the crust and upper mantle. In this study, we summarized the broad-band seismic data acquisitions in the eastern South China Block in the past 2 decades and reported the latest data on the crustal thickness, crustal Vp/Vs ratio, LAB depth, velocity structure, and anisotropy of the upper mantle. This study can not only provide references for future data acquisition but also some basic information for the study of the deep structure, geodynamics, and mineralization in this area.