鄂尔多斯盆地陇东地区延长组中上段有利砂体控制因素及预测  

Control factors and prediction of favorable sand bodies of the middle and upper members of Yanchang Formation in Longdong Area,Ordos Basin

作　　者：徐庚 严雪[1] 吴楠[1] 胡琮 雷宇 张文选 XU Geng;YAN Xue;WU Nan;HU Cong;LEI Yu;ZHANG Wenxuan(School of Geosciences,Yangtze University,Wuhan,Hubei 430100,China;Exploration Department,PetroChina Changqing Oilfield Company,Xi'an,Shaanxi 710018,China)

机构地区：[1]长江大学地球科学学院,湖北武汉430100 [2]中国石油长庆油田分公司勘探事业部,陕西西安710018

出　　处：《东北石油大学学报》2025年第1期45-60,I0004,I0005,共18页Journal of Northeast Petroleum University

基　　金：国家自然科学基金面上项目(42172179)。

摘　　要：三叠系延长组是鄂尔多斯盆地陇东地区主要的含油层系。根据测井、地震、岩心、薄片、物性及含油气性等资料,分析研究区延长组中上段前积层段储层特征及有利砂体控制因素,对有利砂体进行预测。结果表明:鄂尔多斯盆地陇东地区延长组中上段储层岩石类型主要为岩屑长石砂岩、长石岩屑砂岩和长石砂岩;孔隙度主要分布于8.0%~12.0%,渗透率主要分布于(0.10~0.30)×10^(-3)μm^(2),属于致密储层。有利砂体发育受古地貌、沉积相及岩相因素控制,缓坡带和坳陷带为有利砂体最发育的地貌单元,三角洲前缘的水下分流河道微相及深水重力流的砂质碎屑流沉积微相是有利砂体形成的主要沉积相带,块状层理细砂岩相是有利砂体最发育的岩相类型。研究区有利砂体可分为Ⅰ—Ⅲ类,Ⅰ类砂体主要分布于缓坡带的水下分流河道微相,Ⅱ类砂体主要分布于缓坡带及坳陷带的砂质碎屑流沉积微相,Ⅲ类砂体主要分布于斜坡带和坳陷带远端的河道侧缘及浊流沉积微相。该结果对鄂尔多斯盆地陇东地区的下一步勘探具有指导意义。The Triassic Yanchang Formation is the main oil-bearing series in Longdong Area of Ordos Basin.According to the data of logging,seismic,core,thin section,physical property and oil and gas bearing,we analyzed the reservoir characteristics and favorable sand body control factors of the middle and upper member of Yanchang Formation in the study area.Combined with the production dynamic data of the study area,we predicted the favorable sand bodies.The study shows that the reservoir rock types of the middle and upper member of Yanchang Formation in Longdong Area of Ordos Basin are mainly rocky feldspathic sandstone,feldspathic-rocky sandstone and feldspathic sandstone.The porosity is mainly distributed in 8.0%12.0%,and the permeability is mainly distributed in(0.100.30)×10^(-3)μm^(2),which belongs to tight reservoir.The development of favorable sand bodies is controlled by multiple factors such as paleomorphology,sedimentary facies and rock facies.The gentle slope zone and depression zone are the most developed geomorphic units of favorable sand bodies.The subaqueous distributary channel microfacies of the delta front and the sandy clastic flow microfacies of deep water gravity flow are the main facies zones for the formation of favorable sand bodies.The massive bedding fine sandstone facies are the most favorable sand body development of lithofacies types.Favorable sand bodies in the study area can be divided intoⅠ-Ⅲtypes.The type Ⅰ sand bodies are mainly distributed in the microfacies of the underwater distributary channel in the gentle slope zone.The typeⅡsand bodies are mainly distributed in the sedimentary microfacies of sandy clastic flow in gentle slope and depression zones.The typeⅢsand bodies are mainly distributed in the slope zone,the lateral margin of the channel at the distal end of the depression zone and the turbidity sedimentary microfacies.This result has a guiding significance for the next exploration in Longdong Area,Ordos Basin.

关 键 词：控制因素 有利砂体 储层特征 三叠系 延长组中上段 陇东地区 鄂尔多斯盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探] P631.81[天文地球—地质矿产勘探]