西宁盆地下侏罗统烃源岩有机地球化学特征  

Organic Geochemistry of Lower Jurassic Source Rocks in Xining Basin

作　　者：孟元林[1] 杜虹宝 许丞[1] 肖丽华[1] 周新桂[2] 胡安文[1] 

机构地区：[1]东北石油大学地球科学学院,黑龙江大庆163318 [2]中国地质调查局油气资源调查中心,北京100029

出　　处：《天然气地球科学》2014年第4期588-594,共7页Natural Gas Geoscience

基　　金：国家自然科学基金项目(编号:U1262106);全国油气资源战略选区调查与评价国家专项(编号:2009GYXQ13);黑龙江研究生创新科研项目(编号:YJSCX2012-064HLJ)联合资助

摘　　要：在西宁盆地下侏罗统发现了一套湖沼相烃源岩。为了研究该套烃源岩的生烃潜力和赋存页岩油气的可能性,在大茶石浪下侏罗统剖面系统地采集了有机地球化学样品,完成了湖相暗色泥岩和高位沼泽炭质泥岩有机质丰度、类型和成熟度的测试和研究。结果表明,西宁盆地下侏罗统暗色泥岩有机质丰度较高,属于中等偏好的烃源岩,炭质泥岩有机质丰度属于中等偏差的烃源岩;湖相暗色泥岩和高位沼泽相炭质泥岩有机质类型均以Ⅲ1型为主,生油能力较差,生气能力较好;其镜质组反射率分布在0.7%~0.94%之间,已进入大量生烃的成熟阶段。其地球化学特征和世界上许多页岩油气田的烃源岩有相似之处,据此推测,西宁盆地下侏罗统具有形成常规油气和页岩油气的潜力。A set of Lower Jurassic source rock was found in the Xining Basin,Northwestern China.In order to investigate the potential of hydrocarbon generation and the possibility of shale gas and oil formation,the samples in the Lower Jurassic outcrop section of Dachashilang District were collected to measure the abundance,type,and maturity of the organic matters in the lacustrine and HST peat-charcoal shales.The results show that the lacustrine dark shales have the high abundance of organic matter,which are fallen into the area of general-good source rock;the carbonaceous shales have the poor organic matter,which are located within the area of poor-average source rock.Both lacustrine shales and HST carbonaceous shales areⅢ1 type of kerogen which is prone to gas.The vitrinite reflectance values are in range of 0.7%-0.94%,suggesting it would be mature stage for massive hydrocarbon generation.The organic geochemical feature for the Lower Jurassic share is similar with the major shale gas reservoirs in the world.Thus,we suggest that the Riyueshan Formation source rock in Xining Basin would be potential for conventional and unconventional oil and gas exploration.

关 键 词：页岩油气 煤系烃源岩 下侏罗统 西宁盆地 

分 类 号：TE122.113[石油与天然气工程—油气勘探]