中国克拉通盆地油气成藏特点和勘探思路

Oil and gas accumulation in craton basins of China and exploration strategy

克拉通(内)盆地是重要的含油气领域。中国的克拉通破碎性强,经历了多次开合构造旋回并受到晚新生代构造运动的强烈改造,决定了该类盆地油气藏一般有多期多源生烃、晚期定型或成藏的特点,形成原生、准原生和次生油藏的复杂空间组合。其主要成藏控制因素为生烃坳陷、古隆起和古斜坡、不整合和岩溶作用、断裂和裂缝系统、后期保存状况等。适于该类盆地的勘探思路为:确定有效烃源岩,强调古隆起和晚期改造的不同作用,强调对次生储集空间的研究,明确岩性油气藏和天然气勘探的重要地位,自觉地从次生油气藏向近源层逼近,同时还必须形成与之配套的技术工艺体系。

The craton basins in China had been reconstructed by multiple structural cycles, including the Late Cenozoic violent structural movement with strong fragmentation, causing the multi-source and multi-period hydrocarbon generation and the late hydrocarbon accumulation and the progenic and hypo progenic and deuterogenic oil reservoirs compose a complicated spatial combination system in these basins. So the hydrocarbon generating depressions, palaeohigh, palaeoslope, unconformity surfaces, palaeo-karst, faults and framework of fault as well as the conservation conditions in late period become primary factors for controlling the formation of hydrocarbon pools. In consequence, an adaptive exploration strategy for the craton basins of China could be proposed as to identify the effective source rock, attach importance to palaeohigh and late reconstruction and deuterogenic reservoirs, pay attention to the exploration of lithologic deposit and natural gas pool, approach the targets that are closer to the source rocks from the deuterogenic oil pools self-consciously as well as build up a complete set of technologies and techniques.