海域天然气水合物三维地震处理关键技术应用

天然气水合物赋存于海底浅部地层，具有埋深浅、横向变化快等特点，另外在海底浅部地层中还存在大量游离气。为了研究天然气水合物矿体分布范围、厚度情况，在南海首次采用三源十二缆地震采集技术获取了高密度三维地震数据。为了突出水合物反射特征，在三维高分辨率数据处理中，采用五维插值技术消除采集脚印，采用深度域速度模型层析成像多轮迭代技术、Q层析建模技术取得高精度速度模型和Q模型等技术。最终的Q-PSDM成果剖面提高了水合物矿体及下部地层的成像精度，消除了气云区导致的成像假象，为水合物矿体解释奠定基础。

The Key Techniques of 3D Seismic Data Processing for Gas Hydrate

Gas hydrate occurs in strata under the seabed, with the characteristics of shallow buried depth and rapid lateral change. In addition, there is lots of free gas in the shallow seabed. In order to study the distribution and thickness of gas hydrates, 3D seismic acquisition technology with three sources and twelve cables was firstly used to obtain high-density 3D seismic data in the South China Sea. In order to highlight the reflection characteristics of hydrates, five-dimensional interpolation techniques are used to eliminate the acquisition footprints in the three-dimensional high-resolution data processing. And the depth-domain velocity model tomography multi-round iterative technology and Q tomography modeling technology are used to obtain high accuracy velocity model and Q model. The final Q-PSDM results profile improves the imaging accuracy of the hydrate orebody and the underlying strata, eliminates the imaging artifacts caused by gas cloud area, and lays the foundation for the interpretation of the hydrate orebody.