Colorado Plateau/Rio Grande Rift/Great Plains Seismic Transect

粤公网安备44010802000012号 Aster 格兰德河裂谷地震样带（RISTRA）项目旨在利用1999-2001年期间记录的18个月宽频带IRIS PASSCAL数据集研究美国西南部地壳和地幔，这些数据集来自德克萨斯州、新墨西哥州、亚利桑那州和犹他州沿着1000 km样带的57个站点。 在最初的NSF资助下，完成了广泛的实地工作，数据在IRIS数据管理中心进行了处理和存档，并进行了初步分析，并向地球科学和更广泛的社区传播。 该项目继续RISTRA的分析，以前所未有的分辨率阐明和解释与格兰德河裂谷（RGR），科罗拉多高原（CP）和大平原（GP）相关的结构和过程。 主要目标是确定：（1）支持CP目前高海拔的性质;（2）与表面形态和构造相关的地幔过程的深度范围;（3）RGR区域下地幔和地壳应变之间的联系;（4）Farallon板块残余物和任何可能的大陆岩石圈在地幔中的位置。利用接收器函数方法对不连续面进行成像，同时进行剪切波分裂、三维地震层析成像、捕虏体和其他地质/地球物理限制因素的研究，以揭示该区域约800公里深处的结构。目前正在应用地震迁移处理技术，充分利用RISTRA实验的质量、长度和密集（约18公里）的台站间距。弹性2-和3-D建模工作正在与洛斯阿拉莫斯国家实验室和休斯顿大学联合纳入DOE/SEG下一代建模（NGM）项目。

EAR-0207812 Aster The Rio Grande Rift Seismic Transect (RISTRA) project is designed to study the crust and mantle beneath the southwestern U.S. utilizing an exceptional data set consisting of 18 months of broadband teleseismic IRIS PASSCAL data from 57 sites along a 1000-km transect in TX, NM, AZ, and UT recorded during 1999-2001. Under initial NSF funding extensive fieldwork was completed, data were processed and archived at the IRIS data management center, and preliminary analysis was performed and disseminated to the earth science and broader communities. This project continues the analysis of RISTRA to illuminate and interpret structure and processes associated with the Rio Grande Rift (RGR), Colorado Plateau (CP), and Great Plains (GP) at unprecedented resolution. Principal goals are to determine the: (1) nature the support of the present high elevation of the CP; (2) depth extent of mantle processes associated with surface morphology and tectonics; (3) connection between mantle and crustal strain beneath the RGR region; (4) location in the mantle of remnants of the Farallon plate and any possible detached continental lithosphere. Imaging of discontinuities using receiver function methods is being coupled with studies of shear wave splitting, 3-D seismic tomography, xenolith, and other geological/geophysical constraints to reveal the structure of the region to depths of approximately 800 km. Seismic migration processing techniques that take full advantage of the quality, length, and dense (~18 km) station spacing of the RISTRA experiment are being applied. Elastic 2- and 3-D modeling efforts are being incorporated into the DOE/SEG Next Generation Modeling (NGM) Project in association with Los Alamos National Laboratory and the University of Houston.