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)

智力价值：该项目需要重新分析2005年法国赞助的SISMOMAR邮轮期间从大西洋中部海脊幸运罢工火山获得的三维多通道地震数据集，以及来自同一地区更大规模海底地震层析成像实验的数据。由法国领导的研究小组对这些数据的原始分析表明，有明确的证据表明，中大西洋海脊下存在广泛的岩浆透镜。为了观察更精细的结构，特别是区分岩浆体富含熔体和富含晶体的部分(这是一个对海洋地球科学界非常重要的问题)，私人投资者打算采用需要详细了解浅层地壳结构的叠前成像方法。为了实现这一目标，SOBE(合成海底实验)应该能够实现多道地震数据的高分辨率层析成像。这是一种波动方程解，它将震源和接收器外推到海底，并能够检测到MCS拖缆上记录的最浅折射到达波，否则这些波就隐藏在水波中。SOBE应该提供大约10s米的垂直分辨率，以提供叠前成像所需的构造控制，还应该能够突出可能将富熔岩带与热液喷口地区联系起来的地壳上部流体路径和裂缝。如果SOBE方法能够通过对现有数据集的分析得到证明，它将有可能改变海洋多道地震调查。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网站和潘恩论坛的高清立体放映厅分发可视化产品供公众观看。该项目包括一名研究生的研究和培训经验，该研究生将在美国和法国的机构之间平分资金。

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.