Investigation of Three-Dimensional Mantle Structure Beneath the SW Colorado Plateau and Southern Basin and Range

9805149赞特这项研究包括研究加州东南部和亚利桑那州西部地区的地壳和上地幔，该地区覆盖了科罗拉多高原的西南部和南部盆地和山脉的大部分地区。 将对75个测站、200 km × 450 km阵列的现有数据集进行分析，以完成地震层析成像研究，将现有数字布格重力数据建模，并对现有宽带波形进行建模，以表征研究区域的上地幔结构。 这一重要的数据集填补了美国西部高分辨率P波层析成像覆盖范围的巨大空白。该地区的新生代构造历史从俯冲相关的压缩和地壳增厚到造山带坍塌，核心复杂的形成，火山作用和延伸异常良好地记录在地质记录中。 这项研究将限制该地区下的上地幔的现今组成和物理状态，以评估它保留或丢失新生代构造事件的印记的方式。

9805149ZandtThis research involves the study of the crust and upper mantle of the region encompassing southeastern California and western Arizona, which covers the southwest quarter of the Colorado Plateau and much of the southern Basin and Range. An existing data set from a 75-station, 200km by 450km array will be analyzed to complete a seismic tomography study, incorporating modeling of available digital Bouguer gravity data, and to model existing broadband waveforms to characterize the upper mantle structure in the study region. This important data set fills a large gap in high-resolution P-wave tomography coverage for the western U.S. The region's Cenozoic tectonic history of transition from subduction related compression and crustal thickening to orogenic collapse with core complex formation, volcanism, and extension is unusually well documented in the geologic record. This study will constrain the present day composition and physical state of the upper mantle beneath the area to evaluate the ways it has retained, or lost, the imprint of the Cenozoic tectonic events.