Controls of oil family distribution and composition in nonmarine petroleum systems: A case study from Inner Mongolia Erlian basin,Northern China     

《Journal of Asian Earth Sciences》2014

The Erlian basin is a continental rift basin located in Inner Mongolia, Northern China. It is a typical representative of Cretaceous Northeast Asian Rift System, which includes many small petroliferous basins in Mongolia Republic and Northern China. Although Lower Cretaceous source rocks are understood to be most important in the Erlian petroleum systems, the precise identification of these source rock intervals and their determination on oil families distribution and composition are poorly understood in this tectonically complicated, nonmarine basin. New bulk data have been gathered from source rock intervals, oil sands and crude oil samples in eight main oil-producing subbasins. Geochemical analyses indicate that Lower Cretaceous Aershan formation (K₁ba) and Tengger 1 formation (K₁bt₁) are two main source intervals in the Erlian basin and their source rock facies vary from profundal lacustrine to marginal lacustrine according to biomarker and trace elements calibration, the profundal lacustrine facies is characterised by brackish water and anoxic environment, which is similar to their correlative oils (Family 1 oils). The marginal lacustrine facies is characterised by freshwater and suboxic environment, which sourced the most common Family 2 oils. Meanwhile, different maturation processes exercise the second control on oil groups and their compositions, the profundal lacustrine source rocks characterised by their sulphur-rich kerogens lead to two oil groups (group 1 and group 2 oils), whose maturity range from low to normal; while, the marginal lacustrine source rock only lead to normal-maturity oils. At last, biodegradation affected the composition of a certain oils and formed group 4 heavy oils. In addition, short migration distance in small subbasins made the contamination or fractionation less notable in the Erlian basin.  相似文献   

阿尔及利亚三叠盆地、韦德迈阿次盆地石油地质特征及油气勘探中应注意的问题   总被引：12，自引：0，他引：12  

李大荣  黎发文  唐红 《海相油气地质》2006,11(3):19-26

阿尔及利亚在区域上由两大单元组成,北部为撒哈拉阿特拉斯褶皱带,南部为撒哈拉地台。油气田主要分布在撒哈拉地台的三叠盆地和伊利兹盆地。在三叠盆地内已发现50多个油田和37个气田,石油地质储量达23×108t,天然气地质储量达4×1012m3。油气田中以超巨型的哈西迈萨乌德油田和哈西勒迈勒凝析气田最为著名。三叠盆地的烃源岩主要为下志留统Graptolitic组黑色页岩;韦德迈阿次盆地的烃源岩主要为志留系Fegaguria组深灰色—黑色富有机质泥岩。三叠盆地与韦德迈阿次盆地的储盖条件都比较优越,但油藏的埋深较大,且位于沙漠地区,在勘探上应注意“西气东油”的油气分布特征和坚持“立体勘探”的方法。  相似文献   

石油污染对莫桑比克罗非鱼血清酶活性的影响   总被引：8，自引：2，他引：6  

沈竑  张勤  徐韧  王桂兰 《海洋学报》1998,20(4):60-64

本文通过分析莫桑比克罗非鱼血清酶活性的变化,研究石油对鱼类的致毒效应.试验结果表明,石油污染能升高血清谷草转氨酶、乳酸脱氢酶和碱性磷酸酶活性,石油对莫桑比克罗非鱼血清酶活性产生作用的浓度阈值为0.05mg/dm3.分析鱼类血清酶活性的变化,可以为诊断石油污染提供科学依据.  相似文献   

论塔里木盆地形成大油气田的地质条件   总被引：1，自引：0，他引：1  

康玉柱 《现代地质》1992,6(1):39-45

塔里木盆地的油气勘查工作已有40年的历史,取得了丰富的地质资料和油气成果。特别是1984年塔北沙参2并获高产油气流,实现了我国古生代海相油气田的首次重大突破,而后,该盆地的油气勘查工作出现了新高潮。从1988年以来又连续实现了新构造、新层位上的新型油气藏的重大突破。笔者从油气资源、构造条件、成藏条件等方面论述该盆地形成大型——特大型油气田的地质条件。  相似文献