摘要
拉布达林盆地是大庆探区外围西部勘探程度极低的盆地之一。利用偏光显微镜、荧光显微镜和冷热台对大乌尔根尖子山剖面和地质浅井早白垩世上库力组的泥灰岩样品进行了系统研究。研究结果表明:剖面样品中发育早、晚2期碳酸盐脉,分别为方解石脉和白云石脉,其中方解石脉多已发生蚀变,溶孔(洞)中普遍见稠油或稠油沥青。地质浅井样品中仅发育白云石脉,微缝(洞)中见稠油或稠油沥青,泥灰岩裂缝中充填大量黑色沥青脉。碳酸盐脉中油气包裹体极为发育,包裹体液烃呈褐黄色、浅黄色、淡黄色,显示浅黄色、黄白色、暗褐色及褐红色荧光,表明拉布达林盆地曾发生过成熟油气的运聚。方解石脉中的油气包裹体均为次生包裹体,白云石脉中则以原生包裹体为主。白云石脉中含烃盐水包裹体的均一温度为80～145℃,集中分布在85～95℃、110～120℃、135～140℃3个区间,拉布达林盆地油气运聚期应为白云石脉充填期。
The Labudalin basin is one of the underexplored basins in the western periphery of the Daqing oilfield. Marlstone samples from the Early Cretaceous Shangkuh Formation in the Jianzishan section and geological pits in Dawu＇ergen were analyzed systematically using the polarizing microscope, fluorescence microscope and freezing-heating stage. Study indicates that in the samples there occur carbonate veins of two stages： calcite veins in the early stage and dolomite veins in the late stage. Heavy oil or heavy oil-bitumen is observed universally in solution pores or cavities of calcite veins, most of which have been altered. Only dolomite veins are observed in-the samples from pits, and heavy oil or heavy oil-bitumen is also observed in microcracks or cavities of dolomite veins. Abundant gray bitumen veins fill in fractures of marlstone. Petroleum inclusions in carbonate veins are very abundant. Liquid hydrocarbon of the inclusions is brownish yellow and light yellow in color and shows light yellow, yellowish white, dark brown and brownish red fluorescence, which indicates that overmature oil and gas migration and accumulation may have taken place in the Labudalin basin. The petroleum inclusions in calcite veins are secondary, while petroleum inclusions in dolomite veins are mainly primary; the homogeneous temperatures of hydrocarbon-bearing saline inclusions in dolomite veins range from 80 to 145℃, clustering in the ranges of 85-95, 110-120 and 135-140℃. So it is considered that migration and accumulation of petroleum in the Labudalin basin occurred during infilling of dolomite veins.
出处
《地质通报》
CAS
CSCD
北大核心
2007年第7期849-856,共8页
Geological Bulletin of China
基金
国家油气专项(批准号:XQ-2004-07)资助成果
关键词
碳酸盐脉
流体包裹体
油气运聚
早白垩世
拉布达林盆地
carbonate veins
fluid inclusions
migration and accumulation of petroleum
Lower Cretaceous
Labudalin basin
