Lithospheric structure below Dabie Shan, China

中国大别山下方岩石圈结构

• 批准号: 13839433
• 负责人: Professor Dr. Rainer Kind
• 金额: --
• 依托单位: Fachrichtung Geophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/13839433?language=en
• 关键词: Lithospheric; structure; below; Dabie; Shan

The aim of the proposal is to study the structure of the lithosphere and upper mantle in the Qinling-Dabie orogenic belt in China. Outcrop of ultrahigh pressure coesite-bearing eclogite indicates that during collision of lithospheric plates crustal rocks were subducted to large depths and then exhumed. Teleseismic earthquake records (S and P receiver functions) will used to study seismic discontinuities (Moho and lithosphere- asthenosphere boundary, 410 and 660 discontinuities) to obtain images of the geodynamic processes in the region. Thirty four seismic broadband stations of the Institute of Geology of the Chinese Seismological Bureau have been operating with support of the DFG within ICDP in the Dabie Shan region along a 500km long profile between the years 2001 and 2002. The data are stored in Potsdam. Results of a preliminary P receiver function study, which are published in China, show clearly the Moho reaching 42km depth below the center of the orogen. The main goal of the proposed study is to apply the S receiver function technique to map the lithosphere-asthenosphere boundary (LAB) across the Dabie Shan. This technique, although still new, has proven very useful for mapping the LAB at the Hawaiian and Iceland plume tracks (see enclosures). Also across the Tien Shan the LAB was clearly observed with this technique (Kosarev, personal communication). Knowledge about the structure of the complete lithosphere, not only the crust, will significantly improve understand of lithospheric collision processes.

研究秦岭-大别造山带的岩石圈和上地幔结构。超高压含粘质榴辉岩的露头表明，岩石圈板块碰撞过程中，地壳岩石俯冲到较大深度后被掘出。远震地震记录（S和P接收函数）将用于研究地震不连续面（Moho和岩石圈-软流圈边界，410和660不连续面），以获得该地区地球动力学过程的图像。2001年至2002年，中国地震局地质研究所的34个地震宽带站在ICDP DFG的支持下，沿着500公里长的剖面在大别山地区运行。数据存储在波茨坦。中国发表的初步P接收函数研究结果清楚地表明，莫霍线深度在造山带中心以下42km。本研究的主要目的是利用S接收函数技术绘制大别山岩石圈-软流圈边界。这项技术虽然还很新，但已被证明对绘制夏威夷和冰岛羽流轨迹的LAB非常有用（见附件）。同样，通过这种技术，可以清楚地观察到天山的LAB （Kosarev，个人通信）。了解整个岩石圈的结构，而不仅仅是地壳的结构，将大大提高对岩石圈碰撞过程的理解。