Characteristics and hydrocarbon accumulation model of Paleogene whole petroleum system in western depression of Qaidam Basin,NW China  

作　　者：LIU Guoyong WU Songtao WU Kunyu SHEN Yue LEI Gang ZHANG Bin XING Haoting ZHANG Qinghui LI Guoxin 

机构地区：[1]PetroChina Qinghai Oilfield Company,Dunhuang 736202,China [2]Qinghai Provincial Key Laboratory of Plateau Saline-Lacustrine Basinal Oil&Gas Geology,Dunhuang 736202,China [3]PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China [4]PetroChina Company Limited,Beijing 610500,China

出　　处：《Petroleum Exploration and Development》2024年第5期1097-1108,共12页石油勘探与开发（英文版）

基　　金：Supported by the PetroChina Science and Technology Special Project(2021DQ0405,2023ZZ15);National Natural Science Foundation of China(42090025)。

摘　　要：Based on the oil and gas exploration in western depression of the Qaidam Basin,NW China,combined with the geochemical,seismic,logging and drilling data,the basic geological conditions,oil and gas distribution characteristics,reservoir-forming dynamics,and hydrocarbon accumulation model of the Paleogene whole petroleum system(WPS)in the western depression of the Qaidam Basin are systematically studied.A globally unique ultra-thick mountain-style WPS is found in the western depression of the Qaidam Basin.Around the source rocks of the upper member of the Paleogene Lower Ganchaigou Formation,the structural reservoir,lithological reservoir,shale oil and shale gas are laterally distributed in an orderly manner and vertically overlapped from the edge to the central part of the lake basin.The Paleogene WPS in the western depression of the Qaidam Basin is believed unique in three aspects.First,the source rocks with low organic matter abundance are characterized by low carbon and rich hydrogen,showing a strong hydrocarbon generating capacity per unit mass of organic carbon.Second,the saline lake basinal deposits are ultra-thick,with mixed deposits dominating the center of the depression,and strong vertical and lateral heterogeneity of lithofacies and storage spaces.Third,the strong transformation induced by strike-slip compression during the Himalayan resulted in the heterogeneous enrichment of oil and gas in the mountain-style WPS.As a result of the coordinated evolution of source-reservoir-caprock assemblage and conducting system,the Paleogene WPS has the characteristics of“whole process”hydrocarbon generation of source rocks which are low-carbon and hydrogen-rich,“whole depression”ultra-thick reservoir sedimentation,“all direction”hydrocarbon adjustment by strike-slip compressional fault,and“whole succession”distribution of conventional and unconventional oil and gas.Due to the severe Himalayan tectonic movement,the western depression of the Qaidam Basin evolved from depression to uplift.Shale oil is wi

关 键 词：whole petroleum system shale oil Yingxiongling sag ultra-thick mountain-style continuous hydrocarbon accumulation PALEOGENE western depression of Qaidam Basin 

分 类 号：TE34[石油与天然气工程—油气田开发工程] P618.13[天文地球—矿床学]