The Indian National Gas Hydrate Program (NGHP) has conducted two drilling expeditions, discovering concentrated fracture-filling gas hydrate reservoirs and sand reservoirs, which could be the prior areas to exploit gas hydrate in the future. The successful drilling expeditions of NGHP were attributed to enormous basic geological investigations and geophysical research. This paper reviews the geophysical research on gas hydrate reservoirs on the east continental margin of India, analyzes the logic and prospect of the related research, and acquires some ideas and understandings, with a view to guide geophysical studies on gas hydrate reservoirs. First, bottom-simulating reflector and enhanced reflecting indicating fluid flow are important proxies for concentrated gas hydrate reservoirs. Second, some promising research areas are proposed, including the full waveform inversion, the anisotropic resistivity detection, controlled source electromagnetic surveying, and gas hydrate saturation estimation based on the well logs and seismic data.%印度国家天然气水合物计划(NGHP)先后实施了两次钻探,发现了高富集度的裂隙充填型水合物和砂岩储层水合物,确定了未来水合物开采的优先地区.NGHP钻探的成功建立在丰富的基础地质调查和地球物理研究基础上.文章对印度东部大陆边缘的天然气水合物储层地球物理研究工作进行了较全面的总结,分析了相关研究工作的思路和前景,获得了几点思考和认识,希望可以为水合物储层的地球物理研究提供参考借鉴.一是似海底反射和强反射振幅等流体活动标志是识别高富集度水合物的有力指示;二是提出了水合物储层地球物理研究应该重点关注的几个方向,包括:全波形反演的应用、各向异性电阻率探测、可控源电磁勘探以及基于地震测井数据的水合物饱和度估算方法等.
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