Coll. Res: Advanced MCS processing of the SISMOMAR 3D data volume: Exploring linkages within the magmatically driven hydrothermal system of the Lucky Strike Volcano (MAR, 37deg N)

知识价值：该项目需要重新分析2005年法国赞助的SISMOMAR巡航期间从大西洋中脊的Lucky Strike火山获得的三维多通道地震数据集，以及同一地区更大规模的海底地震层析实验数据。由法国领导的研究小组对这些数据进行的原始分析表明，在大西洋中脊之下存在广泛的岩浆透镜体。为了观察更精细的结构，特别是为了区分岩浆体中富含熔体和富含晶体的部分（一个对海洋地球科学界非常重要的问题），pi打算采用叠前成像方法，这需要对浅层地壳结构有详细的了解。为此提出的SOBE（合成海底实验）方法应该能够实现多通道地震数据的高分辨率层析成像。这是一种波方程解，可以将源和接收器外推到海底，并可以检测到MCS拖缆上记录的最浅折射到达，否则就会隐藏在水波中。SOBE应提供10米左右的垂直分辨率，以提供叠前成像所需的构造控制，还应使其能够突出显示可能连接富熔体带和热液喷口场的上部地壳流体路径和裂缝。如果SOBE方法可以通过对现有数据集的分析得到验证，它将有可能改变海洋多通道地震调查。更广泛的影响：更广泛的影响包括MCS数据分析和解释的能力建设，以及通过RidgeView网站和Paine论坛的高清立体投影剧院向公众发布可视化产品。该项目包括一名研究生的研究和培训经历，将由美国和法国机构共同资助。

Intellectual Merit: The project entails a re-analysis of a 3-d multichannel seismic data set obtained from the Lucky Strike volcano, Mid-Atlantic Ridge during the French-sponsored SISMOMAR cruise in 2005, and data from a larger-scale ocean bottom seismic tomographic experiment in the same region. The original analysis of these data by a French-led group shows clear evidence for an extensive magma lens beneath the Mid-Atlantic Ridge. In order to look at finer-scale structure, and particularly to distinguish between melt-rich vs crystal-laden sections of the magma body (a question of great importance to the marine geoscience community), the PIs intend to employ a prestack imaging approach which requires detailed knowledge of shallow crustal structure. The method proposed to achieve this, SOBE (synthetic ocean bottom experiment) should enable high resolution tomography of multichannel seismic data. This is a wave equation solution that extrapolates sources and receivers to the seafloor and enables detection of the shallowest refracted arrivals recorded on the MCS streamer that otherwise are hidden in the water waves. SOBE should provide vertical resolution on the order of 10s of meters to provide the structural controls required for prestack imaging, and should also make it possible to highlight the upper crustal fluid pathways and fractures that may be linking melt-rich zones to the hydrothermal vent fields. If the SOBE method can be proven through the analysis of this existing data set, it has the potential to transform marine multichannel seismic investigations. Broader Impacts: Broader impacts include capacity building for MCS data analysis and interpretation, and distribution of visualization products for public viewing through the RidgeView website, and at an HD stereo projection theatre at the Paine Forum. The project includes research and training experiences for a graduate student to be split funded between US and French institutions.