“SGR下限法”在判别古油藏中的应用  

The application of“SGRlower limit method”in recognizing paleoreservoir

作　　者：范婕 蒋有录[3] 宋明水[1] 林会喜[1] 张奎华[1] 秦峰[1] 曾治平[1] 朱建峰[4] FAN Jie;JIANG Youlu;SONG Mingshui;LIN Huixi;ZHANG Kuihua;QIN Feng;ZENG Zhiping;ZHU Jianfeng(SINOPEC Research Institute of Exploration and Development,Shengli Oilfield Company,Dongying,Shandong 257015,China;Working Station for Postdoctoral Scientific Research,Shengli Oilfield,Dongying,Shandong 257000,China;School of Geosciences,China University of Petroleum,Qingdao,Shandong 266580,China;SINOPEC Geoscience Research of Exploration and Development,Northeast Branch Corporation,Changchun,Jilin 130062,China)

机构地区：[1]中国石化胜利油田分公司勘探开发研究院,山东东营257015 [2]胜利石油管理局博士后科研工作站,山东东营257000 [3]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [4]中国石化东北油气分公司,吉林长春130062

出　　处：《中国矿业大学学报》2020年第4期755-764,共10页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(41972140);胜利油田管理局博士后科研课题(YKB1901)。

摘　　要：针对现有古油藏识别方法具有多解性,亦不能定量判断的问题,从构造破坏型古油藏的成因入手,提出了“SGR下限法”,并应用于松辽盆地东岭地区.基于油气成藏动力学分析,将储层、盖层排替压力以及超压考虑在内,建立油气运移临界条件方程,据此计算SGRlim,并以此作为断-盖配置的评价指标.利用最大断距相减法恢复古断距,并对地层厚度去压实,计算SGR古.通过对比SGRlim,SGR现今,SGR古这3个数值的大小,评价不同时期断-盖配置特征,认为当“SGR古≥SGRlim”且“SGR现今<SGRlim”可形成古油藏.应用该方法对松辽盆地东岭地区进行研究,结果表明:第1期油气成藏时,营三段泥岩盖层断-盖配置关系较好,SGR古大于SGRlim,大量原生油气藏富集于营三段盖层之下;第2期油气成藏时,随着断裂的持续活动,营三段盖层被断裂断穿,SGR现今小于SGRlim,古油藏遭到破坏,沿断裂垂向运移至断-盖配置关系较好的泉二段泥岩盖层下.明确了SN109井、SN182井、S8井、SN110井、S1井、SN188井存在古油藏,岩心、镜下沥青及包裹体观察、GOI值、原油物性等证据也佐证了古油藏的存在,证明了SGR下限法的准确性和可应用性.At present,most of the methods of recognizing paleoreservoir have obvious drawbacks,such as multiple solutions and the non-quantitative analysis.Under the investigation of a structural destructive paleoreservoir in the Songliao Basin of Dongling area,a new approach named"shale gouge ratio(SGR)lower limit method"was proposed by analyzing the origin of structural destructive paleoreservoir.This new approach is based on the analysis of accumulation dynamics,many important factors,such as reservoir displacement pressure,caprock displacement pressure and reservoir overpressure,are taken into consideration when a hydrocarbon migration critical condition equation is established.Then,the SGRlim(SGRlower limit)is calculated and regarded as an index to assess the fault-caprock configuration.Utilizing the largest displacement subtraction method,the ancient fault distance is recovered,and then the stratigraphic thickness is decompressed,so that the ancient SGRcan be obtained.Comparing the value of SGRlim,present SGRand ancient SGR,the fault-caprock configuration can be assessed in different hydrocarbon accumulation periods.And it is considered that when"ancient SGRis equal or greater than SGRlower limit"and"present SGRis smaller than SGRlower limit",it is possible to form paleoreservoir.In the case of Dongling area in Songliao Basin,the ancient SGRis higher than SGRlim,so that there is a good fault-caprock configuration of shale caprock of K1yc3 formation in the first stage of hydrocarbon accumulation,therefore the primary reservoirs are enriched under it.While K1yc3 caprock is destroyed by faults with the continuous activity of faults in the second stage of hydrocarbon accumulation,the present SGRis smaller than SGRlim,then hydrocarbon migrated vertically along the fault and accumulated under the mudstone caprock of K1q2 formation with good fault-caprock configuration.Consequently,it was determined that the locations of paleoreservoir in study area were wells of SN109,SN182,S8,SN110,S1and SN188.Furthermore,the evidences fou

关 键 词：古油藏 SGR下限 断-盖配置 东岭地区 松辽盆地 

分 类 号：P618.13[天文地球—矿床学]