Characteristics of Water Breakthrough and Optimization of Production System of Oil Wells Drilled in Ultra-Deep Fault-Karst Reservoirs: A Case Study on Well Z in Shunbei Oilfield, Tarim Basin

doi:10.7657/XJPG20210506

Abstract

Abstract:

In order to optimize the production system after water breakthrough in the oil wells drilled in ultra-deep fault-karst reservoirs and taking Well Z in Shunbei oilfield in Tarim basin as a case, the characteristics of reservoir geology and water breakthrough in the oil wells were analyzed through reservoir engineering method and numerical simulation. The well productivities before and after water breakthrough were compared, the water invasion rate and producing reserves were calculated, the water channeling characteristics was studied based on numerical simulation and the production system after water breakthrough was optimized. The results show that: 1) The inflow performance curve of Well Z is upturned, because the fluid flows at a higher rate after reducing the bottom hole flowing pressure or increasing the bottom hole producing pressure difference, and new fractures and caves open and more flowable channels occur, resulting in a great increase of the oil productivity in the well; 2) After water breakthrough, the daily oil production dropped sharply, and the productivity reduced dramatically; 3) The producing reserves in Well Z are about 338×10⁴ t, bottom water invaded in January 2020 at a rate of about 0.61×10⁴ m³/month, and by November 3, 2020, the water cone in Well Z was about 395 m from the initial oil-water contact and about 131 m from the bottom hole. According to the results, a 7 mm choke was recommended and used in Well Z. After field application, the daily oil production has increased from 96 t to 170 t and the water cut has been controlled less than 2.00%, indicating a satisfactory result.

Key words: Tarim basin, Shunbei oilfield, ultra-deep fault-karst reservoir, oil well, water breakthrough characteristic, inflow performance curve, rational production system, deep and large fault

CLC Number:

TE344

CHENG Xiaojun. Characteristics of Water Breakthrough and Optimization of Production System of Oil Wells Drilled in Ultra-Deep Fault-Karst Reservoirs: A Case Study on Well Z in Shunbei Oilfield, Tarim Basin[J]. Xinjiang Petroleum Geology, 2021, 42(5): 554-558.

Figures/Tables 10

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References 17

[1]	焦方正. 塔里木盆地顺北特深碳酸盐岩断溶体油气藏发现意义与前景[J]. 石油与天然气地质, 2018, 39(2):207-216.
	JIAO Fangzheng. Significance and prospect of ultra-deep carbonate fault-karst reservoirs in Shunbei area,Tarim basin[J]. Oil & Gas Geology, 2018, 39(2):207-216.
[2]	漆立新. 塔里木盆地顺托果勒隆起奥陶系碳酸盐岩超深层油气突破及其意义[J]. 中国石油勘探, 2016, 21(3):38-51.
	QI Lixin. Oil and gas breakthrough in ultra-deep Ordovician carbonate formations in Shuntuoguole uplift,Tarim basin[J]. China Petroleum Exploration, 2016, 21(3):38-51.
[3]	漆立新. 塔里木盆地顺北超深断溶体油藏特征与启示[J]. 中国石油勘探, 2020, 25(1):102-111.
	QI Lixin. Characteristics and inspiration of ultra-deep fault-karst reservoir in the Shunbei area of the Tarim basin[J]. China Petroleum Exploration, 2020, 25(1):102-111.
[4]	云露. 顺北地区奥陶系超深断溶体油气成藏条件[J]. 新疆石油地质, 2021, 42(2):136-142.
	YUN Lu. Hydrocarbon accumulation of ultra-deep Ordovician fault-karst reservoirs in Shunbei area[J]. Xinjiang Petroleum Geology, 2021, 42(2):136-142.
[5]	顾浩, 尚根华, 李慧莉, 等. 基于井温的超深断溶体油藏油井动用深度计算[J]. 特种油气藏, 2021, 28(2):57-62.
	GU Hao, SHANG Genhua, LI Huili, et al. Calculation of production depth of oil wells in ultra-deep fault-karst reservoirs based on well temperature[J]. Special Oil & Gas Reservoirs, 2021, 28(2):57-62.
[6]	云露. 顺北东部北东向走滑断裂体系控储控藏作用与突破意义[J]. 中国石油勘探, 2021, 26(3):41-52.
	YUN Lu. Controlling effect of NE strike-slip fault system on reservoir development and hydrocarbon accumulation in the eastern Shunbei area and its geological significance,Tarim basin[J]. China Petroleum Exploration, 2021, 26(3) :41-52.
[7]	何治亮, 金晓辉, 沃玉进, 等. 中国海相超深层碳酸盐岩油气成藏特点及勘探领域[J]. 中国石油勘探, 2016, 21(1):3-14.
	HE Zhiliang, JIN Xiaohui, WO Yujin, et al. Hydrocarbon accumulation characteristics and exploration domains of ultra-deep marine carbonates in China[J]. China Petroleum Exploration, 2016, 21(1):3-14.
[8]	顾浩, 康志江, 尚根华, 等. 基于物质平衡的超深断溶体油藏弹性驱产能主控因素分析[J]. 油气地质与采收率, 2021, 28(4):86-92.
	GU Hao, KANG Zhijiang, SHANG Genhua, et al. Analysis of main controlling factors for elastic flooding productivity of ultra-deep fault-karst reservoirs based on material balance[J]. Petroleum Geology and Recovery Efficiency, 2021, 28(4):86-92.
[9]	鲁新便, 胡文革, 汪彦, 等. 塔河地区碳酸盐岩断溶体油藏特征与开发实践[J]. 石油与天然气地质, 2015, 36(3):347-355.
	LU Xinbian, HU Wenge, WANG Yan, et al. Characteristics and development practice of fault-karst carbonate reservoirs in Tahe area,Tarim basin[J]. Oil & Gas Geology, 2015, 36(3):347-355.
[10]	鲁新便, 杨敏, 汪彦, 等. 塔里木盆地北部“层控”与“断控”型油藏特征:以塔河油田奥陶系为例[J]. 石油实验地质, 2018, 40(4):461-469.
	LU Xinbian, YANG Min, WANG Yan, et al. Geological characteristics of ‘strata-bound’ and ‘fault-controlled’ reservoirs in the northern Tarim basin:taking the Ordovician reservoirs in the Tahe oil field as an example[J]. Petroleum Geology & Experiment, 2018, 40(4):461-469.
[11]	韩俊, 况安鹏, 能源, 等. 顺北5号走滑断裂带纵向分层结构及其油气地质意义[J]. 新疆石油地质, 2021, 42(2):152-160.
	HAN Jun, KUANG Anpeng, NENG Yuan, et al. Vertical layered structure of Shunbei No.5 strike-slip fault zone and its significance on hydrocarbon accumulation[J]. Xinjiang Petroleum Geology, 2021, 42(2):152-160.
[12]	邬光辉, 陈志勇, 曲泰来, 等. 塔里木盆地走滑带碳酸盐岩断裂相特征及其与油气关系[J]. 地质学报, 2012, 86(2):219-227.
	WU Guanghui, CHEN Zhiyong, QU Tailai, et al. Characteristics of the strike-slip fault facies in Ordovician carbonate in the Tarim basin,and its relations to hydrocarbon[J]. Acta Geologica Sinica, 2012, 86(2):219-227.
[13]	宋佳佳, 孙建孟, 王敏, 等. 断层内部结构研究进展[J]. 地球物理学进展, 2018, 33(5):196-206.
	SONG Jiajia, SUN Jianmeng, WANG Min, et al. Research progress in the internal structure of the fault[J]. Progress in Geophysics, 2018, 33(5):196-206.
[14]	李映涛, 漆立新, 张哨楠, 等. 塔里木盆地顺北地区中—下奥陶统断溶体储层特征及发育模式[J]. 石油学报, 2019, 40(12):1 470-1 484.
	LI Yingtao, QI Lixin, ZHANG Shaonan, et al. Characteristics and development mode of the Middle and Lower Ordovician fault-karst reservoir in Shunbei area,Tarim basin[J]. Acta Petrolei Sinica, 2019, 40(12):1 470-1 484.
[15]	张琪. 采油工程原理与设计[M]. 山东东营: 中国石油大学出版社, 2006.
	ZHANG Qi. Oil recovery principle and design[M]. Dongying, Shandong:China University of Petroleum Industry Press, 2006.
[16]	李传亮. 油藏工程原理[M]. 北京: 石油工业出版社, 2011.
	LI Chuanliang. Principle of reservoir engineering[M]. Beijing: Petroleum Industry Press, 2011.
[17]	刘德华, 刘志森. 油藏工程基础[M]. 北京: 石油工业出版社, 2004.
	LIU Dehua, LIU Zhisen. Foundation of reservoir engineering[M]. Beijing: Petroleum Industry Press, 2004.