塔河奥陶系油藏岩溶储层类型、洞穴结构和发育模式:以塔河油田7区T615缝洞单元为例  

Karst Reservoir Type,Cave Structure and Genetic Model of Ordovician Tahe Reservoirs:Case Study of Fracture-cavity Unit T615 in Tahe Oilfield 7 Block

作　　者：徐嘉宏 康志宏[1] 蓝茜茜 XU Jiahong;KANG Zhihong;LAN Xixi(School of Energy Resources,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质大学(北京)能源学院,北京100083

出　　处：《现代地质》2020年第6期1181-1192,共12页Geoscience

基　　金：中国地质科学院地质力学研究所项目“重点地区构造体系及油页岩气控藏条件调查”(DD20190085)。

摘　　要：塔河奥陶系碳酸盐岩油藏储集体以岩溶缝洞为主,随着油田开发深入和地球物理技术长足进展,岩溶暗河地下形态渐为明晰。但由于岩溶缝洞储集体具有空间结构复杂、岩溶产物和储集体类型多样等特点,以至于岩溶储集体类型、结构和发育模式分歧较大。以T615缝洞单元为实例,以高分辨采集的地震资料为基础,结合单元内岩心、录井、测井、FMI成像测井和单井动态等资料,将井区内储集体划分为机械充填型(砂泥岩充填和细砂岩充填)、垮塌角砾充填型、溶洞(未充填)型和溶蚀裂缝4种类型。结合高分辨采集的三维地震属性刻画资料,对典型岩溶系统主要岩溶产物(厅堂洞、干流洞、末梢洞、落水洞和驻水洞)的分布特征及识别标志进行研究,将岩溶划分为4个期次。经过构造和充填改造,在4层洞穴中,洞穴结构、岩溶产物和储集体类型具有较大差异。结合水文地质和岩溶理论,建立典型岩溶系统的连井岩溶缝洞地质剖面图和连井缝洞发育模式图,揭示井间缝洞组合关系,对岩溶储层描述和表征具有指导意义。The Ordovician Tahe carbonate reservoirs are dominated by karst fractures and caves.With the advance of oilfield development and geophysical surveying technology,the morphology of karst underground rivers has become clearer.However,due to the complex spatial structure,karst products and the types of reservoirs,structures and development patterns of karst reservoirs differ greatly.Take the fracture-cavity unit T615 as an example,we used high-resolution seismic data,together with core logging,FMI imaging logging,and single-well performance data,the reservoirs in the well area are divided into four types,i.e.filling(sand-mudstone filling and fine sandstone filling),collapsed-breccia filling,karst cave(unfilled)and dissolution crack types.Combined with the collected high-resolution 3D seismic attribute characterization data,the distribution characteristics and identification marks of the major products(hall cave,main stream cave,terminal cave,falling water cave and resident water cave)of typical karst systems are studied,and the karst formation is divided into 4 periods.After structural and filling reconstruction,different cave structures,karst products and reservoir types are found in the four-layer cave.Integrating hydrogeology and karst theory,the geological profile of the continuous well karst fractures and caves,and their genetic model in a typical karst system are established.This reveals the combination of fractures and caves between wells,and provides guidance for the description and characterization of karst reservoirs.

关 键 词：碳酸盐岩 缝洞储集体 储集体类型 岩溶产物 发育模式 

分 类 号：TE122.2[石油与天然气工程—油气勘探]