Comprehensive evaluation method for preferential seepage channels in massive unconsolidated sandstone reservoirs

doi:10.3969/j.issn.1006-6535.2025.06.013

Abstract

Abstract: To address the adverse impact of preferential seepage channels formed during long term water flooding in unconsolidated sandstone reservoirs on development performance,this study takes Z Oilfield as a case study to propose a refined identification method for preferential seepage channels in massive unconsolidated sandstone reservoirs by integrating geological data with production dynamics and employing comprehensive evaluation algorithms,numerical simulation and reservoir engineering methods.The study shows that preferential seepage channels in Area Y can be classified into three intensity grades (strong, moderate and weak) based on their developmental characteristics, reservoir damage degree and waterflooding-induced impacts on remaining oil distribution.Key evaluation indicators include geological factors such as reservoir rhythm,cementation index, porosity, permeability and dynamic production parameters.Through cluster analysis of 589 well datasets using an improved K-means algorithm, a graded evaluation criterion was established.The plane distribution of preferential seepage channels is identified using an entropy-weighted TOPSIS algorithm, their development depth via time-variant numerical simulation and their development direction through reservoir multi-information inversion.Applying these findings to Oilfield Z and implementing channel governance shows significant results with the recovery rate projected to reach 61.54% in 5 years and a cumulative oil increase of 158.5×10⁴ t, greatly improving water-flooding efficiency.This research offers crucial scientific insights for long-term water-flooding reservoir development and enhancing water-flooding efficiency.

Key words: massive sandstone reservoirs, preferential seepage channels, graded evaluation criteria, comprehensive identification methods

CLC Number:

TE349

WU Lijuan, ZHU Qixing, WU Wenjie, LOU Yishan, YANG Xiao. Comprehensive evaluation method for preferential seepage channels in massive unconsolidated sandstone reservoirs[J]. Special Oil & Gas Reservoirs, 2025, 32(6): 107-115.

References

[1] 王凤兰,石成方,田晓东,等.大庆油田“十一五”期间油田开发主要技术对策研究[J].大庆石油地质与开发,2007,24(2):62-66.
WANG Fenglan,SHI Chengfang,TIAN Xiaodong,et al.Study on main technical strategy of oilfield development during "the eleventh five-year plan" in Daqing Oilfield[J].Petroleum Geology & Oilfield Development in Daqing,2007,24(2):62-66.
[2] 姜学实.大庆油田水驱开发技术提档升级[J].石油知识,2022,38(2):27.
JIANG Xueshi.Upgrading of water flooding development technology in Daqing Oilfield[J].Petroleum Knowledge,2022,38(2):27.
[3] 吴振东,邓广耀,宋子军,等.井间示踪剂监测技术在复杂小断块油藏中的应用[J].石油天然气学报,2007,29(3):237-239,512.
WU Zhendong,DENG Guangyao,SONG Zijun,et al.Application of interwell tracer detection in complex small fault block reservoirs[J].Journal of Oil and Gas Technology,2007,29(3):237-239,512.
[4] 王森.利用压力资料识别优势通道方法研究[D].青岛:中国石油大学(华东),2012.
WANG Sen.Research on the method of identifying dominant channels based on pressure data[D].Qingdao:China University of Petroleum(East China),2012.
[5] 高慧梅,姜汉桥,陈民锋.疏松砂岩油藏大孔道识别的典型曲线方法[J].石油天然气学报,2009,31(1):108-111,393.
GAO Huimei,JIANG Hanqiao,CHEN Minfeng.Typical curves of identification of high capacity channel in unconsolidated sand-stone oil reservoirs[J].Journal of Oil and Gas Technology,2009,31(1):108-111,393.
[6] REYES-LOPEZ C,MAHX-ROJANO M A,ASADI M,et al.An interwell water flood study-flow pattern and reservoir heterogeneity evaluation of a northern field formation in Mexico,part 1-upper section of the field[C].SPE94226,2005,10(1):22.
[7] BANE R K,PAKER R A,STOBECK W G,et al.Reser-voir management of the Fullerton Clearfork Unit[C].SPE27640,1994,9(2):11-20.
[8] AL-DHAMEN A A,PHAM T R,AL-KHATIB M R.A quick method of identifying and history matching a gravity dominated reservoir with localized super-permeabilities[C].SPE49276,1998,30(1):13-30.
[9] 党旭.注水前后储层变化特征及动态建模研究[J].非常规油气,2023,10(6):75-81.
DANG Xu.Study on reservoir variation characteristics and dynamic modeling before and after water injection[J].Unconventional Oil & Gas,2023,10(6):75-81.
[10] 王经荣,王继强.提高高含水期油藏数值模拟历史拟合效率方法[D].西安:西安石油大学,2021.
WANG Jingrong,WANG Jiqiang.Methods to improve reservoir numerical simulation history fitting efficiency in high water cut period[D].Xi′an:Xi′an Shiyou University,2021.
[11] 韩晓冬.水驱砂岩油藏储层参数变化网络模拟研究[D].青岛:中国石油大学(华东),2014.
HAN Xiaodong.Study on network simulation of reservoir parameter variation in water drive sandstone reservoirs[D].Qingdao:China University of Petroleum(East China),2014.
[12] 孙常伟.一种计算水驱油藏高含水期驱油效率的新方法[J].中外能源,2022,27(11):58-62.
SUN Changwei.A new method for calculating oil displacement efficiency of water drive reservoirs at high water cut stage[J].Sino-Global Energy,2022,27(11):58-62.
[13] 陈永生.油藏流场[M].北京:石油工业出版社,1998:112-139.
CHEN Yongsheng.Reservoir flow field[M].Beijing:Petroleum Industry Press,1998:112-139.
[14] 徐春梅,张荣,马丽萍,等.注水开发储层的动态变化特征及影响因素分析[J].岩性油气藏,2010,22(增刊1):89-92.
XU Chunmei,ZHANG Rong,MA Liping,et al.Reservoir dynamic variation characteristics after water flooding and its influencing factors[J].Lithologic Reservoirs,2010,22(S1):89-92.
[15] 刘天,刘小平,孙彪,等.苏北盆地金湖凹陷三河次凹有效烃源岩评价[J].科学技术与工程,2022,22(16):6463-6473.
LIU Tian,LIU Xiaoping,SUN Biao,et al.Evaluation on effective source rocks of Sanhe Subsag in Jinhu Sag,Subei Basin[J].Science Technology and Engineering,2022,22(16):6463-6473.
[16] 郭莉,王延斌,刘伟新,等.大港油田注水开发过程中油藏参数变化规律分析[J].石油实验地质,2006,44(1):85-90.
GUO Li,WANG Yanbin,LIU Weixin,et al.Variation law of reservoir parameters during waterflooding in Dagang Oil Field[J].Petroleum Geology & Experiment,2006,44(1):85-90.
[17] 盖英杰,吕德灵,郭元灵.高含水期油藏分阶段数值模拟[J].油气采收率技术,2000,7(1):54-56.
GAI Yingjie,LYU Deling,GUO Yuanling.Numerical simulation by stages about the reservoir at high water cut period[J].Oil and Gas Recovery Efficiency Technology,2000,7(1):54-56.
[18] 姜瑞忠,陈月明,邓玉珍,等.胜坨油田二区油藏物理特征参数变化数值模拟研究[J].油气采收率技术,1996,3(2):50-56.
JIANG Ruizhong,CHEN Yueming,DENG Yuzhen,et al.Numerical simulation of the reservoir physical properties in the second block of Shengtuo Oil Field[J].Oil and Gas Recovery Efficiency Technology,1996,3(2):50-56.
[19] 崔传智,赵晓燕.考虑油藏储层参数变化的数值模拟研究[J].水动力学研究与进展(A辑),2004,19(增刊1):912-915.
CUI Chuanzhi,ZHAO Xiaoyan.The reservoir numerical simulation study with the variety of reservoir parameters[J].Chinese Journal of Hydrodynamics(Series A),2004,19(S1):912-915.
[20] 崔传智,耿正玲,王延忠,等.水驱油藏高含水期渗透率的动态分布计算模型及应用[J].中国石油大学学报(自然科学版),2012,36(4):118-122.
CUI Chuanzhi,GENG Zhengling,WANG Yanzhong,et al.Calculation model of dynamic permeability distribution and its application to water drive reservoir at high water cut stage[J].Journal of China University of Petroleum(Edition of Natural Sciences),2012,36(4):118-122.
[21] 陈洪才,王昭凯,金忠康,等.中低渗砂岩油藏水驱后期油藏再评价及提高采收率对策[J].特种油气藏,2024,31(4):133-141.
CHEN Hongcai,WANG Zhaokai,JIN Zhongkang,et al.Re-evaluation of medium-low permeability sandstone reservoirs in the later stage of water flooding and strategies to improve recovery efficiency[J].Special Oil & Gas Reservoirs,2024,31(4):133-141.
[22] 司睿,石成方,王英圣,等.基于驱替单元的水驱油藏动用状况分类评价方法[J].大庆石油地质与开发,2023,42(1):73-82.
SI Rui,SHI Chengfang,WANG Yingsheng,et al.Classification and evaluation method of water flooded reservoir producing performance based on displacement units[J].Petroleum Geology & Oilfield Development in Daqing,2023,42(1):73-82.
[23] 刘国超,曹瑞波,闫伟,等.聚驱后油层优势渗流通道参数计算方法及其应用[J].大庆石油地质与开发,2023,42(5):90-98.
LIU Guochao,CAO Ruibo,YAN Wei,et al.Calculation method and its application of reservoir dominant flow path parameters after polymer flooding[J].Petroleum Geology & Oilfield Development in Daqing,2023,42(5):90-98.
[24] 刘媛,赵帅,周文胜,等.水驱油田断层封闭性动态评价模型[J].断块油气田,2024,31(5):877-884.
LIU Yuan,ZHAO Shuai,ZHOU Wensheng,et al.Dynamic evaluation model of fault sealing in water drive oilfield[J].Fault-Block Oil & Gas Field,2024,31(5):877-884.
[25] 赵文景,王敬,钱其豪,等.非均质油藏水驱优势渗流通道演化规律[J].断块油气田,2023,30(5):847-857.
ZHAO Wenjing,WANG Jing,QIAN Qihao,et al.Evolution law of dominant flow channels of water flooding in heterogeneous reservoir[J].Fault-Block Oil & Gas Field,2023,30(5):847-857.