气顶油藏动态诊断新方法研究与应用  

Research and Application of a New Method for Dynamic Diagnosis of Gas⁃Cap Reservoirs

作　　者：伍锐东 王睿 马恋 张春光 宋刚祥 石美雪 路颖 WU Ruidong;WANG Rui;MA Lian;ZHANG Chunguang;SONG Gangxiang;SHI Meixue;LU Ying(Research Institute,Shanghai Branch,CNOOC,Shanghai 200335,China)

机构地区：[1]中海石油(中国)有限公司上海分公司研究院,上海200335

出　　处：《新疆石油地质》2024年第5期574-580,共7页Xinjiang Petroleum Geology

基　　金：中国海洋石油有限公司重大科技专项(KJZX-2024-0102)。

摘　　要：气顶油藏在开发过程中存在原油、溶解气、气顶气、凝析油、地层水等多相流体。准确计算地层压力及各相采出程度是该类型油气藏动态诊断及剩余油气挖潜的关键。目前已有的地层压力计算方法难以有效考虑水侵等多种复杂驱动能量,导致各相采出劈分不确定性较大,增加了调整挖潜风险。通过水侵量拟合及牛顿迭代求解法,建立了1套以水侵特征分析及平均地层压力求解为基础的气顶油藏动态诊断新方法。该方法在M油田Y3气顶油藏应用结果表明,Y3气顶油藏产出油中原油占比为89.7%,凝析油占比仅为10.3%,产出气中气顶气占比为97.9%,溶解气占比仅为2.1%,气顶气与凝析油采出程度分别高达46.6%和31.2%,原油及溶解气采出程度仅为12.1%和1.7%,该结果与生产测试结果一致。During the development of gas-cap reservoirs,crude oil,dissolved gas,gas-cap gas,condensate oil,and formation water may be produced simultaneously.Accurately calculating formation pressure and recovery percent of each phase is crucial for dynamic diagnosis and potential tapping of remaining oil and gas in such reservoirs.Current methods for calculating formation pressure fail to take water invasion into consideration,leading to uncertainty in production splitting,which increases the risks in subsequent adjustment and potential tapping.Through water influx fitting and Newton iteration methods,a new method for dynamic diagnosis of gas-cap reservoirs based on water invasion characteristic analysis and average formation pressure prediction was established.The application of this method in the Y3 gas-cap reservoir in the M oilfield indicates that crude oil and condensate oil account for 89.7%and 10.3%in the produced oil,respectively,and the produced gas contains 97.9%gas-cap gas and only 2.1%dissolved gas.The recovery efficiency of gas-cap gas and condensate oil is as high as 46.6%and 31.2%,respectively,while the recovery efficiency of crude oil and dissolved gas is merely 12.1%and 1.7%,respectively.These results are consistent with production test results.

关 键 词：气顶油藏 动态诊断 水侵 平均地层压力 分相产出 剩余油气挖潜 

分 类 号：TE372[石油与天然气工程—油气田开发工程]