古地貌对塔中地区鹰山组岩溶结构及分布的控制作用  

Controlling of paleogeomorphology to characteristics and distribution of karst structures of Yingshan Formation in Tazhong area

作　　者：耿晓洁 林畅松[2] 吴斌 GENG Xiaojie1, LIN Changsong2, WU Bin3(1. Office of Acadamic Affairs, China University of Geosciences, Beijing 100083, China; 2. School of Ocean Sciences China University of Geosciences, Beijing 100083, China; 3. CNOOC Research Institute Ltd., Beijing 100028, Chin)

机构地区：[1]中国地质大学(北京)教务处,北京100083 [2]中国地质大学(北京)海洋学院,北京100083 [3]中海油研究总院有限责任公司,北京100028

出　　处：《岩性油气藏》2018年第4期46-55,共10页Lithologic Reservoirs

基　　金：国家自然科学基金项目"塔里木盆地古生代关键变革期的古构造古地理演化及油气聚集"(编号:41130422)及"塔中地区晚奥陶世碳酸盐台地边缘沉积演化及其对古构造和海平面变化的响应"(编号:41502104)联合资助

摘　　要：古地貌是控制塔中地区鹰山组岩溶储层发育的重要外部因素之一。在对地震剖面进行精细解释的基础上,采用地层趋势外延法对鹰山组沉积之后的古地貌进行了恢复,划分出岩溶地貌单元,并对不同地貌单元的岩溶剖面进行了解剖。结果表明:塔中地区鹰山组的岩溶结构具有表层洞穴发育型、隔层-渗流带发育型和渗流带-潜流带发育型等3种类型。岩溶古地貌单元的分布受区域构造带控制作用明显。其中,塔中10号断裂构造带是主要的岩溶高地,该构造带作为地下水的主要补给区,发育有大型溶蚀洞穴,这些溶蚀洞穴在地震剖面上通常表现为"串珠状"反射。塔中10号断裂带与塔中Ⅰ号断裂带之间为岩溶斜坡区,该构造带作为地下水体的侧向补给区,水流方向从垂向渗流为主变为水平潜流为主,是潜流带洞穴和裂缝最为发育的地区。古地貌的低洼地带是岩溶洼地的主要分布区,岩溶洼地几乎没有岩溶储层发育。这种从岩溶高地到岩溶斜坡再到岩溶洼地的古地貌格局,可以促进溶蚀性流体从高势区向低势区的自然运移,为岩溶储层的连片发育提供了良好的构造背景。Paleogeomorphology is one of the important external factors for the development of karst reservoir of Yingshan Formation in Tazhong area. Based on fine interpretation of seismic section,stratigraphic trend extrapolation method was adopted to restore the geomorphology after the deposition of Yingshan Formation,the karst geomorphic units were divided and the karst sections of different geomorphic units were dissected. The results show that there are three types of karst profiles including surface caves,interlayer-vadose zones and vadose-phreaticzones induced from karst structures. The distribution of paleogeomorphology units is controlled by the structural belts to a great extent. Karst highland is located in the No. 10 fault belt primarily. It is the main recharge area of groundwater with developing large karst caves. The beaded reflections on the seismic profile are this kind of structure. There is karst slope area between No. 1 and No. 10 faulted belts. It is the lateral recharge area of groundwater. The direction of water flow is from vertical seepage to groundwater flow. Hyporheic zone caves and fractures mainly developed in this area. There are basically not karst reservoirs in the karst depression area. This geomorphic pattern promotes the natural migration of dissolution fluid from the high potential region to the low and provides favorable tectonic settings for continuous development of karst reservoir.

关 键 词：地层趋势外延法 古地貌 岩溶结构 鹰山组 塔中地区 

分 类 号：TE122[石油与天然气工程—油气勘探]