U.S.-Canada: A Study of the Abitibi-Grenville Lithosphere by Teleseismic Analyses: Upper Mantle Anisotropy and Heterogeneity

29322499 Hearn美洲项目奖将支持拉斯克鲁塞斯新墨西哥州立大学的Thomas Hearn博士和加拿大魁北克省蒙特利尔综合理工学院的Marianne Mareschal博士之间的研究合作。他们建议沿着Lithoprobe Abitibi-Grenville地质样带部署一个被动源地震阵列，以补充地震反射剖面和大地电磁数据。本研究的主要目的是验证该地区地幔地震各向异性和地幔结构都与元古代和太古代造山带有关的假设。该地点是检验这一假设的一个合乎逻辑的地点，既因为现有的岩石探测器数据，又因为样带位于加拿大盾的一部分，经历了元古代和太古代的主要变形。该项目结合了加拿大国家地球科学研究项目Lithoprobe的专业知识，以及美国地震学联合研究机构（IRIS）提供的独特能力。虽然Lithoprobe项目的重点是利用勘探技术调查地壳，但IRIS将提供其PASCAL便携式地震阵列，该阵列更适合调查上地幔结构。加拿大小组将重点分析旅行时间数据，而美国小组将主要分析剪切波数据。＊＊＊

29322499 Hearn This Americas Program award will support a research collaboration between Dr. Thomas Hearn of New Mexico State University, Las Cruces and Dr. Marianne Mareschal, Ecole Polytechnique, Montreal, Quebec, Canada. They propose to deploy a passive-source seismic array along the Lithoprobe Abitibi-Grenville Geologic Transect to complement seismic reflection profiles and magnetotelluric data. A primary goal of this study is to test the hypothesis that both mantle seismic anisotropy and mantle structure in the region are related to Proterozoic and Archean orogenic episodes. The site is a logical place to test such hypothesis, both because the available Lithoprobe data and because the transect lies over a portion of the Canadian shield that experienced major Proterozoic and Archean deformation. This project combines the expertise of Lithoprobe, Canada's national, earth science research project, with the unique capabilities provided by the U.S. Incorporated Research Institutions for Seismology (IRIS). While the Lithoprobe project has focused on investigating the crust using exploration techniques, IRIS will provide its PASCAL portable seismic array, which is more suited for investigating upper mantle structure. The Canadian group will focus on the analysis of travel time data, while the U.S. group will work primarily with the analysis of shear-wave data. ***