关键词: 滴南凸起, 石炭系, 古火山机构, 火山岩储层, 气藏类型, 成藏模式

Abstract: The Carboniferous ancient volcanic edifices are complex, and have an important impact on the formation, distribution, exploration and development of the gas reservoirs in the Dinan bulge of the Junggar Basin. Based on the interpretation results of new drilling, logging and 3D seismic data, the characteristics of the Carboniferous ancient volcanic edifices and their control on the gas reservoirs were studied and analyzed in the Dinan bulge. The study gives the conclusions as follows: a. According to the morphology of the volcanic edifices and the composition of the volcanic rock, the Carboniferous ancient volcanic edifices can be divided into four types including fractured lava volcanic edifice, central single-crater clastic volcanic edifice, central multi-crater composite volcanic edifice and fractured intrusive volcanic edifice. Controlled by volcanic eruption and sedimentary cycles, the Early Carboniferous volcanic edifices are mainly central single-crater clastic volcanic edifices and fractured intrusive volcanic edifices, and the Late Carboniferous are dominated by fractured lava volcanic edifices. b. The ancient volcanic edifices control the type and distribution of high-quality reservoirs: the fractured lava volcanic edifices contain basaltic reservoirs, the central single-crater clastic volcanic edifices have breccia and dacite reservoirs, and the central multi-crater composite volcanic edifices have breccia and basalt reservoirs, and the fractured intrusive volcanic edifices provide granite porphyry reservoirs. c. Controlled by the ancient volcanic edifices, there are inside-volcano gas reservoirs, weathering crust gas reservoirs, and structural-lithologic gas reservoirs; and the ancient volcanic edifices connecting to deep and large faults are favorable targets for hydrocarbon migration.