压力封存箱的储层特征及其对油气成藏的影响——以渤海湾盆地渤中坳陷石臼坨凸起东倾没端QHD35-A井为例  

Reservoir characterization of pressure sequestration boxes and its implications forhydrocarbon formation:A case study of the Well QHD35-A at the east pitchingend of Shijiutuo Bulge in the Bozhong Depression, Bohai Bay Basin

作　　者：于江茗 曲希玉 王清斌 苗长盛 闫振 YU Jiangming;QU Xiyu;WANG Qingbin;MIAO Changsheng;YAN Zhen(School of Geoscience and Technology,China University of Petroleum(East China),Qindao 266580,China;Tianjin Branch of CNOOC,Tianjin 300450,China;College of Surveying and Mapping Engineering,Changchun Engineering College Changchun 130021,China)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]中海石油(中国)有限公司天津分公司,天津300450 [3]长春工程学院勘察与测绘工程学院,吉林长春130021

出　　处：《天然气地球科学》2024年第6期949-960,共12页Natural Gas Geoscience

基　　金：国家自然科学基金项目(编号:41372133);山东省自然科学基金面上项目(编号:ZR2020MD027)联合资助。

摘　　要：渤中坳陷位于渤海湾盆地中心,是渤海海域内最大的富生烃坳陷,其中深层古近系东营组和沙河街组普遍发育超压,同时也是整个渤海湾盆地超压发育范围和幅度比较大的区域。针对异常高孔隙带的成因及其对油气成藏影响,以渤海湾盆地渤中坳陷石臼坨凸起东倾没端QHD35⁃A井深层异常高孔隙发育带为研究对象,利用镜下观察及测录井分析等方法,根据构造背景、沉积背景、储集空间类型及储层物性等方面的研究成果证实了压力封存箱的存在,并从油气运移及保存的角度探讨了其对油气成藏的影响。具体认识为:①QHD35⁃A井沙二段存在明显的压力封存箱特征:顶底均存在厚层泥岩,侧向存在断裂封堵及泥岩的岩性封闭,中部厚层砂岩保留有大量的原生孔隙;成岩作用等也均表明其地层封闭性较好;②该区压力封存箱的存在对油气成藏具有一定的积极影响,其顶板、底板及侧向的封隔为油气保存提供了良好的条件,内部异常压力一方面为油气的运移提供动力,另一方面也通过改善储层物性为油气运移提供通道。该研究成果对于此类地质条件下封存箱的识别、利用及封闭的有效性研究具有指导与借鉴作用。The Bozhong Depression,situated in the heart of the Bohai Bay Basin,is the largest hydrocarbonrich depression in the Bohai Sea.It is characterized by the development of deep Paleoproterozoic Dongying and Shahejie formations,which are generally associated with overpressure.This study focuses on the deep anoma⁃lous high porosity zone in the Well QHD35-A at the east pitching end of Shijiutuo Bulge in the Bohai Bay Basin.The research employs microscopic observation and well logging analysis to investigate the cause of the anoma⁃lous high porosity zone and its influence on oil and gas reservoirs.The existence of a pressure sealing box was confirmed based on the research results on tectonic background,depositional background,type of reservoir space,and physical properties of reservoirs.The pressure sealing box,characterized by thick mudstone at the top and bottom and large primary pores in the thick sandstone in the middle,has a significant impact on the transportation and preservation of oil and gas.The sealing of the top,bottom,and lateral directions,along with the internal anomalous pressure,provides conditions conducive to oil and gas preservation and transportation.The findings of this research are beneficial for the identification and utilization of storage tanks and the effective⁃ness of their closure under such geological conditions.

关 键 词：渤中坳陷 压力封存箱 古近系 油气成藏 

分 类 号：TE122.1[石油与天然气工程—油气勘探]