Collaborative Research: ACCRETE: An Integrated Study of Continental Growth at a Margin

合作研究：ACCRETE：大陆边际增长的综合研究

• 批准号: 9218489
• 负责人: Maria Crawford
• 金额: $ 10.14万
• 依托单位: Bryn Mawr College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-01 至 1997-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9218489&HistoricalAwards=false
• 关键词: Collaborative; Research; ACCRETE; Integrated; Study

9218489 Crawford This project involves a pilot seismic profile designed to improve understanding of processes of continental growth associated with terrane accretion in the Coast orogen of southeast Alaska and British Columbia. The seismic data will provide constraints pertaining to models for the role of thick-skinned thrusting, metamorphism and magmatism in the formation of continental lithosphere. They will also constrain models on how subduction and translation were accommodated during a major shift in relative plate motions from head-on (mid Cretaceous) to transcurrent (Eocene), and how this rearrangement affected crustal development. The seismic results will guide design of subsequent research proposals on these problems. The seismic profiling will use an acoustic source array deployed from a marine research ship that crosses the Coast orogen along a 130 km long fjord, and densely spaced (3-5 km) 3-component seismic recorders placed along the shore to record offsets from 0 to 200 km. The ship will also deploy a 4 km long hydrophone streamer for simultaneous MCS (multi-channel seismic) profiling. This unique experiment combines proven marine seismic techniques with the new capability of the seismic recorders to determine mid to lower crustal structure and physical properties of an area of known continental accretion. ***

9218489 Crawford 该项目涉及试点地震剖面，旨在提高对阿拉斯加东南部和不列颠哥伦比亚省海岸造山带地体增生相关大陆生长过程的了解。 地震数据将为厚皮逆冲、变质作用和岩浆作用在大陆岩石圈形成中的作用模型提供约束。 他们还将限制有关板块运动从正面（白垩纪中期）到横流（始新世）的重大转变期间如何适应俯冲和平移的模型，以及这种重新排列如何影响地壳发育。 地震结果将指导后续针对这些问题的研究方案的设计。 地震剖面将使用从沿着 130 公里长的峡湾穿越海岸造山带的海洋研究船部署的声源阵列，以及沿着海岸放置的密集间隔（3-5 公里）3 分量地震记录仪，以记录从 0 的偏移量至200公里。 该船还将部署一条 4 公里长的水听器拖缆，用于同步 MCS（多道地震）剖面分析。 这项独特的实验将经过验证的海洋地震技术与地震记录仪的新功能相结合，以确定已知大陆增生区域的中下地壳结构和物理特性。 ***