辽西建昌地区中—新元古界原生油气藏成藏条件分析

摘要

Jianchang area is a small residual structural basin that is located in western Liaoning province.The Mesoproterozoic Tieling and Hongshuizhuang Formations and Neoproterozoic Xiamaling Formation are the main source rocks in this basin.The determination of organic geochemistry indexes shows that the Hongshuizhuang argillaceous shale,Tieling shale and most of Xiamaling shale reach to the medium to good grades of hydrocarbon source rock.If there are opening fractures and unconformity surfaces being hydrocarbon pathways,these source rocks can match with marine and transitional facies carbonate and sandstone reservoirs into favorite source-reservoir-seal assemblages.Due to Mesozoic intensive nappe tectonism experienced during the Indosinian and Yanshan movements,many types of structural traps could develop.Combined with the analysis of oil-source correlation,it is shown that primary Meso-Neoproterozoic oil reservoirs would develop and consequently a hydrocarbon accumulation model is suggested.%辽宁西部建昌地区为一残留型构造盆地,中—新元古界中发育以下马岭组、铁岭组、洪水庄组为主要生油层的烃源岩系.有机质地化指标测定表明洪水庄组泥页岩、铁岭组页岩和下马岭组泥页岩大部分达到好-优烃源岩标准,配合在海相及海陆过渡相时期发育的碳酸盐岩储层和砂岩储层,在断裂和不整合面疏通的情况下具有较好的生储盖组合.中生代经历了印支运动和燕山运动强烈的推覆构造作用,发育多种类型构造圈闭.结合油源对比分析,表明中—新元古界发育古生古储型油气藏,提出了相应的成藏模式.