塔中40油田东河砂岩不整合复合体及油气分布规律  

Donghe Sandstone Unconformity Complex and Oil-Gas Distribution in Tazhong-40 Oilfield in Tarim Basin

作　　者：徐怀民[1] 徐寅[1] 牛玉杰[2] 佘姣凤[2] 王培俊[2] 李猛[2] 

机构地区：[1]中国石油大学地球科学学院,北京102249 [2]中国石油塔里木油田分公司勘探开发研究院,新疆库尔勒841000

出　　处：《新疆石油地质》2013年第3期251-254,共4页Xinjiang Petroleum Geology

基　　金：国家科技重大专项(2011ZX5001-3)

摘　　要：综合运用地震、测井和钻井资料,将塔中40油田东河砂岩划分为均质段、上交互段和含砾砂岩段,识别出含砾砂岩段底部不整合面,确立了东河砂岩不整合复合体层序及岩性结构分类方案,并进一步定量分析不整合复合体不同层序结构地层的孔隙度、渗透率和含油饱和度。研究结果认为,研究区东河砂岩不整合复合体层序地层结构为Ⅰ1和Ⅰ2型,部分区域发育Ⅰ4型。岩性结构属于Ⅰ2和Ⅱ2亚类。不整合复合体下伏海侵体系域(TST)以砂岩沉积为主,孔渗好,含油性相对较差;高位体系域以砂岩沉积为主,孔渗和含油性均较好,顶部有一套泥岩和粉砂岩隔层,发育有断层-不整合遮挡型油气藏和断层-背斜型油气藏。不整合复合体上覆地层低位体系域(LST)中,砂泥交互沉积,砂岩孔渗和含油性相对较好,以断层-岩性型油气藏为主。海侵体系域中,泥包砂,孔渗较差,含油性一般,以断层-岩性型油气藏为主。By using the seismic, well logging and drilling information, the Donghe sandstone unconformity complex in Tazhong-40 oilfield of Tarim basin is divided into homogeneous section, upper cross-bedding section and conglomeratic sandstone section, identifying the bot- tom unconformity of the conglomeratic sandstone section, establishing the unconformity complex sequence and lithologic structure classifi- cation, by which the porosity, permeability and oil saturation of strata with different sequential structures in the complex are quantitatively analyzed. The results show that the structures of the sequence stratigraphy of Donghe sandstone unconformity complex include Type-L and 12 with local Type-L, the lithological structure belongs to Sub-Type-I2 and II2. The underlying transgressive systems tract （TST） of the uncon- formity complex is dominated by sand sediment, with high porosity and permeability as well as relatively poor oil saturation; the highstand systems tract （HST） is dominated by sandstone sediment, with relatively high porosity, permeability and oil saturation, developing a set of mudstone and siltstone harrier on the top of it, and fault-unconformity sheltered and fault-anticline reservoirs. The overlying lowstand sys- tems tract （LST） of the unconformity eomplex is characterized by sand-mud interbedded sediments, with relatively high porosity, permeabili- ty and oil saturation, mainly developing fauh-lithologic reservoir. Its TST is characterized by arenaceous mudstone, poor porosity and per- meability, and medium oil saturation, mainly developing fauh-lithologic reservoir.

关 键 词：塔里木盆地 不整合复合体 东河砂岩 油气分布 

分 类 号：TE112.422[石油与天然气工程—油气勘探]