Seismic Tomography of China and Surrounding Regions

中国及周边地区地震层析成像

• 批准号: 0001227
• 负责人: Thomas Hearn
• 金额: $ 17.02万
• 依托单位: New Mexico State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0001227&HistoricalAwards=false
• 关键词: Seismic; Tomography; China; Surrounding; Regions

Hearn, Thomas M.EAR-0001227This project focuses on upper mantle structure beneath China and surrounding regions of the Asian continent. Asian tectonics is now dominated by the Indian-Asian continental collision and uplift of the Tibetan Plateau in the south and subduction along the eastern margin. Reactivated fold belts accommodate much of the deformation. These fold belts formed during the Phanerozoic amalgamation of cratonic blocks and blocks along eastern Eurasia. It is not clear, however, what the relationship of these blocks and fold belts are to their deeper mantle structure. Lithospheric thickness, collisional downwellings, and mantle anisotropy remain inadequately resolved. The tomography will use P phases from 0 to past 50 degrees distance to image the upper mantle beneath China and its surrounding regions. A key development in the tomography is the introduction of anisotropy. Previous tomographic studies show that anisotropy is essential to the problem and cannot be ignored. Anisotropic tomography has been developed and applied to the two-dimensional Pn problem. This proposal will extend anisotropic tomography to three-dimensions and apply it to the Asian data sets.

托马斯·赫恩 M.EAR-0001227 该项目重点研究中国及亚洲大陆周边地区下方的上地幔结构。 亚洲构造现在主要是印度-亚洲大陆碰撞以及青藏高原南部的隆起和东部边缘的俯冲。 重新激活的折叠带可容纳大部分变形。 这些褶皱带是在克拉通地块和欧亚大陆东部地块显生宙合并期间形成的。 然而，目前尚不清楚这些块体和褶皱带与其更深的地幔结构之间的关系。 岩石圈厚度、碰撞下降流和地幔各向异性仍然没有得到充分解决。 层析成像将使用0到超过50度距离的P位相来对中国及其周边地区下方的上地幔进行成像。 断层扫描的一个关键发展是各向异性的引入。 先前的断层扫描研究表明，各向异性对于该问题至关重要，不容忽视。 各向异性断层扫描技术已被开发并应用于二维 Pn 问题。 该提案将各向异性断层扫描扩展到三维，并将其应用于亚洲数据集。