渤海湾盆地东营凹陷盐家地区深层砂砾岩油气藏相态演化及成藏过程  

Phase evolution and accumulation mode of hydrocarbons in deep coarse-grained clastic reservoirs in the Yanjia area,Dongying Sag,Bohai Bay Basin

作　　者：王永诗[1] 巩建强[2] 陈冬霞[3] 邱贻博[2] 茆书巍 雷文智 杨怀宇[2] 王翘楚 WANG Yongshi;GONG Jianqiang;CHEN Dongxia;QIU Yibo;MAO Shuwei;LEI Wenzhi;YANG Huaiyu;WANG Qiaochu(Shengli Oilfield Branch Company,SINOPEC,Dongying,Shandong 257000,China;Exploration and Development Research Institute,Shengli Oilfield Branch Company,SINOPEC,Dongying,Shandong 257015,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China)

机构地区：[1]中国石化胜利油田分公司,山东东营257000 [2]中国石化胜利油田分公司勘探开发研究院,山东东营257015 [3]中国石油大学(北京)地球科学学院,北京102249

出　　处：《石油与天然气地质》2023年第5期1159-1172,共14页Oil & Gas Geology

基　　金：中国石化科技攻关项目(P21034-1)。

摘　　要：渤海湾盆地东营凹陷北部陡坡带盐家地区深层油气藏经历了复杂的热演化过程,使得深层油气相态类型多变,影响着深层油气勘探开发。通过盆地模拟、pVT相态模拟和烃类流体包裹体等综合分析,揭示了盐家地区深层油气相态演化过程,建立了不同类型油气成藏模式。研究表明,东营北带盐家地区古近系沙河街组四段深层油气多种相态垂向有序分布,从浅至深依次发育轻质油、凝析气和干气等多类型油气藏。深层砂砾岩体中油气相态主要受到热演化的控制,而干酪根生烃、原油裂解和外部天然气充注主导了凝析气藏的相态演化过程。基于盐家地区深层砂砾岩体不同类型油气藏的油气相态、储层特征和温压演化史,建立了盐家深层“多期生油气,扇中叠置输导-扇根封堵,多相态有序分布”的砂砾岩油气成藏模式,为陆相断陷盆地深层油气的高效勘探提供理论指导。Deep hydrocarbon reservoirs in the Yanjia area in the northern steep slope zone of the Dongying Sag experienced complex thermal evolution.The resultant multiple hydrocarbon phases pose challenges for the exploration and exploitation of deep hydrocarbons.Using basin modeling,pressure-volume-temperature(p VT) phase simulation,and the analysis of hydrocarbon fluid inclusions,we reveal the evolutionary process of deep hydrocarbon phases in the Yanjia area and establish the hydrocarbon accumulation modes of different types of reservoirs.Findings indicate that deep hydrocarbons in the 4th member of the Shahejie Formation in the Yanjia area exhibit an orderly phase distribution in the vertical direction,with reservoirs of light oil,condensate gas,and dry gas found from shallow to deep.While thermal evolution predominantly governed the formation of hydrocarbon phases in deep coarse-grained clastic rocks,the phase evolution in condensate gas reservoirs stemmed from hydrocarbon generation from kerogen,crude oil cracking,and external natural gas charging.By integrating insights into the hydrocarbon phases,characteristics,and temperature and pressure evolutionary histories of different hydrocarbon reservoirs,we propose a hydrocarbon accumulation mode for deep coarse-grained clastic rocks in the Yanjia area.This mode encompasses multi-stage hydrocarbon generation,migration via superimposed sand beds within middle fans while sealed by mudstone within root fans,and the orderly phase distribution of hydrocarbons.This study seeks to provide theoretical guidance for the efficient exploration of deep hydrocarbons in continental downfaulted basins.

关 键 词：pVT相态模拟 盆地模拟 油气相态演化 油气成藏模式 深层砂砾岩体 古近系 东营凹陷 渤海湾盆地 

分 类 号：TE122.3[石油与天然气工程—油气勘探]