Dynamics of Extensional Convergent Margins and the Origin of Supra-Subduction Zone Ophiolites: Hypothesis Testing in the Tonga Forearc

9521023布卢默这个项目由俄勒冈州州立大学的谢尔曼布卢默博士进行，支持一次研究巡航和随后的数据分析，旨在了解太平洋西南部汤加俯冲系统的发展。 这个收敛的边缘被假设为代表一个简单的端员这样的俯冲系统，快速收敛和一个简单的板缘几何形状允许测试的一系列假设的地质演化的“弧前”系统。 该计划将包括详细的海底成像，以研究断层分布，地球物理研究（地震反射，重力和磁力），以检查地下结构，以及广泛的岩石采样，以检查弧系统的发展地球化学。 特别令人感兴趣的是蛇纹岩底辟的分布和弧系统中热液流体迁移的证据。 这个项目是支持与奖励9521039博士黎明赖特，也在俄勒冈州州立大学，其支持下的NSF教师早期职业发展（职业生涯）计划。 该奖项为赖特博士提供了四年的支持，以开发海洋和地质科学的新的跨学科课程，促进本科生和高中生的科学事业，并在海洋生物物理学的不同方面开展双管齐下的研究计划。 拟议研究的第一部分侧重于研究汤加前弧的地球物理发展，Wright博士将参加实地方案，她将主要负责对项目期间收集的地球物理数据进行巡航后分析。 ***

9521023 Bloomer This project by Dr. Sherman Bloomer of Oregon State University supports a research cruise and subsequent data analysis aimed at understanding the development of the Tonga subduction system in the southwestern Pacific. This convergent margin is hypothesized to represent a simple end-member of such subduction systems, where rapid convergence and a simple plate margin geometry allow testing of a series of hypotheses regarding geologic evolution of the "forearc" system. The program will include detailed seafloor imaging to study fault distribution, geophysical studies (seismic reflection, gravity and magnetics) to examine subsurface architecture, and extensive rock sampling to examine the development of the arc system geochemically. Of particular interest will be the distribution of serpentinite diapirs and evidence of hydrothermal fluid migration in the arc system. This project is supported in collaboration with award 9521039 to Dr. Dawn Wright, also at Oregon State University, whose support comes under the NSF Faculty Early Career Development (CAREER) Program. That award provides support for Dr. Wright over four years to develop new, interdisciplinary courses in the marine and geological sciences, to promote scientific careers to undergraduate and high school students, and to carry out a two-pronged research program in different aspects of marine geophysics. The first part of the proposed research focusses on the study of the geophysical development of the Tonga forearc, and Dr. Wright will participate in the field program, and she will have principal responsibility for post-cruise analysis of the geophysical data collected during the project. ***