A 3-D Seismic Investigation of the Sediment-to-Rock Transition and Its Relationship to Nankai Subduction Thrust Seismicity: U.S.-Japan Collaborative Program

9730637该奖项将支持地震反射、折射和被动地震活动计划，以研究沿日本东海岸南开海槽的洋壳俯冲作用。本实验要考察的主要特征是俯冲逆冲断层从其海槽(海沟)中的无震区到大陆边缘以下至少15公里处的深度，在那里逆冲具有显著的地震活动。这项研究的目标是检查推力从抗震到地震表现时物理性质的变化。理解这种从压实和非地震滑动到脆性破坏的转变是理解岩石圈消耗和地震动力学的一个主要未知因素。这一南开孕震带标志着日本边缘地区发生重大破坏性地震的地点。该项目是一项合作实验。美国科学家将负责获取和解释来自逆冲断层和隆起边缘的三维地震反射数据。日本同事将负责部署海底地震仪，用于地震折射和被动地震活动研究。除了从数据中得出基本的科学解释外，该实验对开展边缘倡议至关重要，并将为国际大洋钻探计划未来的钻探提供必要的现场位置数据。***

9730637 Bangs this award will support a seismic reflection, refraction and passive seismicity program to study underthrusting of oceanic crust along the Nankai Trough off the east coast of Japan. The primary feature to be examined in this experiment is the subduction thrust fault from its aseismic zone in the Trough (trench) to a depth of at least 15 kilometers beneath the continental margin where the thrust is marked by significant seismic activity. The goal of the study is to examine changes in physical properties along the thrust as it changes from aseismic to seismic expression. Understanding this transition from compaction and aseismic slip to brittle failure is a major unknown in understanding lithospheric consumption and earthquake dynamics. This Nankai seismogenic zone marks the location of major destructive earthquakes along the Japanese margin. The project is a collaborative experiment. United State scientists will be responsible for acquiring and interpreting 3-dimensional seismic reflection data from the thrust fault and accreting margin. Japanese colleagues will be responsible for deploying ocean bottom seismometers for seismic refraction and passive seismicity studies. In addition t the basic scientific interpretation to be derived from the data, the experiment is critical to the development of the MARGINS initiative and will provide necessary site location data for future drilling by the international Ocean Drilling Program. ***