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从杭州湾地区全新世超浅层生物气所赋存的沉积背景入手，分析了该区沉积相及其展布，并恢复了与生物气时空分布密切相关的沉积相在古河谷形成演变规律。在此基础上，重点解剖最具代表性的夹灶生物气藏，探讨了超浅层生物气藏典型特征。研究表明：末次盛冰期低海面，河流下切形成４０～１００ｍ深的钱塘江古河谷，冰后期海平面上升，古河谷被充填和覆盖。河漫滩和浅海泥质沉积物既是气源岩，又是盖层，后者可作为区域盖层；分布在古河谷的河漫滩砂质透镜体为唯一具工业价值的储气层，气藏为岩性圈闭，属自生自储同生型。含气砂层顶界面在浅层横波地震剖面上表现出强的反射面，当含气砂体横向尖灭，反射波急剧减弱，据此可圈定含气砂体的边界。
Starting from the sedimentary background of the Holocene ultra-shallow biogenic gas in the Hangzhou Bay area, the sedimentary facies and distribution of the sedimentary facies in the area were analyzed. The formation and evolution of sedimentary facies closely related to the biogas space-time distribution were restored. On this basis, the most representative anatomical biogas reservoirs are dissected, and the typical characteristics of ultra-shallow biogas reservoirs are discussed. The results show that the sea level of the Qiantang River with the depth of 40 ~ 100m is undercut during the last glaciation, and the sea level rises in the late ice period. The ancient valley is filled and covered. River floodplains and shallow sea muddy sediments are both gas source rocks and cap rocks, and the latter can be used as regional cap rocks. The river flood beach sand lenses distributed in the ancient valleys are the only gas reservoirs with industrial value. The gas reservoirs are lithology Trap, is a spontaneous self-storage type. The top surface of gas-bearing sand layer shows strong reflection surface on the shallow shear wave seismic section. When the gas-bearing sand body is pointed out laterally and the reflected wave abruptly weakens, the boundary of gas-bearing sand body can be delineated.