Lateral Variations in Seismic Structure of Atlantis Massif Oceanic Core Complex

该奖项是根据2009年美国复苏和再投资法案（公法111-2）资助的。洋核杂岩暴露出侵入基性岩和地幔超基性岩透镜体，它们受扩展中心轴向带内长寿命的滑脱断裂控制。PI将分析亚特兰蒂斯地块现有的MCS OBS数据，并从对该海洋核心复合体的详细分析中获得结构见解，这将使她能够将其与其他核心复合体进行比较。基于这些地点之间的一致性或缺乏一致性，她将测试OCC形成和演变的当前模型。亚特兰蒂斯地块现有的地震数据将允许PI记录1.5公里以上的相当详细的结构（垂直分辨率为10米）和更大范围的结构（垂直分辨率为几百米）至4-7公里的岩石圈深度。通过结合MCS和OBS折射数据，她将获得一个沿网格线的速度模型，该网格线覆盖了该OCC的每个结构组件。由此产生的层析模型将使她能够确定可能的基性侵入体的范围和连续性，表征这些侵入体与具有正常速度-深度特性的地壳之间的过渡，并将OCC的穹窿核与相邻上壁和共轭外角地壳的特征进行比较。该项目很大一部分是为了支持研究生完成博士论文。它还将允许进一步开发用于MCS折射分析的SOBE处理系统，这是一项主要的社区服务，并且它可能有助于未来在亚特兰蒂斯地块的钻探。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-2).Oceanic core complexes (OCC) expose intrusive mafic rocks and lenses of mantle ultramafic rock, that are controlled by long-lived detachment faulting within the axial zone of a spreading center. The PI will analyze existing MCS OBS data at Atlantis Massif and the structural insights gained from detailed analysis of this oceanic core complex will allow her to compare it with other core complexes. Based on consistencies between the sites, or lack thereof, she will test current models of OCC formation and evolution. The existing seismic data at Atlantis Massif will allow the PI to document fairly detailed structure (several 10's m vertical resolution) within the upper ~1.5 km and broader scale structure (few-hundred meters vertical resolution) to lithospheric depths of 4-7 km. By combining MCS and OBS refraction data, she will obtain a velocity model along a grid of lines that cover each structural component of this OCC. The resulting tomographic model will allow her to determine the extent and continuity of likely mafic intrusive bodies, to characterize the transition between these bodies and crust that has normal velocity-depth properties, and to compare the signature of the domal core of the OCC to that of the adjacent hanging wall and conjugate outside corner crust. The project is large part for the support of a graduate student for the completion of a Ph.D. thesis. It will also allow further development of the SOBE processing system for MCS refraction analysis, a major community service, and it may help in future drilling on the Atlantis Massif.