Collaborative Research: Seismic Characterization of a Gas Hydrate System in the Gulf of Mexico - A Novel Approach to Evaluate High-Resolution Wide-Angle Data

在一个联合项目中，美国地质勘探局、密西西比大学和美国能源部收集了墨西哥湾天然气水合物环境的单通道地震和海底地震仪数据。初步结果显示，在含水合物的泥底辟下存在游离气体，但缺乏模拟底部反射器（BSR）。pi建议进一步开发现有的地震层析成像代码，以自一致的方式处理反射界面和转换剪切波。该规范将首先应用于墨西哥湾密西西比峡谷地区的一个有趣的天然气水合物问题。这项新技术将用于了解：1)浅层水合物在海底下延伸多远？2)浅层水合物下是否存在游离气体？如果存在，是什么将其封存？3)为什么没有BSR的存在。对现有三维数据进行优化，开发基于层析反演的三维PS-NMO方法。

In a joint project USGS, University of Mississippi and the DOE gathered single-channel seismic and ocean bottom seismometer data from the Gulf of Mexico gas hydrate environment. Initial results show free gas beneath a hydrate-bearing mud diapir but lacks a bottom-simulating reflector (BSR). The PIs propose to further develop an existing seismic tomography code to handle reflecting interfaces and converted shear waves in a self-consistent way. The code will be initially applied to an interesting gas hydrate problem from the Mississippi Canyon area in the Gulf of Mexico. The new technique will be used to learn: 1) how far does the shallow hydrates extend beneath the seafloor?, 2) does free gas exist beneath shallow hydrates and if so, what traps it?, 3) why is there no BSR present. The existing 3D data will be optimized and a method will be developed for 3D PS-NMO based on tomographic inversion.