特低渗透油藏注水诱导动态裂缝实验及数值模拟

梁卫卫; 党海龙; 刘滨; 张天龙; 王小锋; 侯玢池; 崔鹏兴; 王谦; 张凤远

doi:10.11781/sysydz202303566

特低渗透油藏注水诱导动态裂缝实验及数值模拟

doi: 10.11781/sysydz202303566

梁卫卫^{1, 2,},
党海龙^{1, 2, ,},
刘滨^{1, 2},
张天龙^{1, 2},
王小锋^{1, 2},
侯玢池^{1, 2},
崔鹏兴^{1, 2},
王谦^{1, 2},
张凤远³

1.
陕西延长石油(集团)有限责任公司研究院, 西安 710065
2.
陕西省特低渗透油气田勘探与开发工程技术研究中心, 西安 710065
3.
中国石油大学(北京) 石油工程学院, 北京 102249

基金项目:

陕西省科技统筹创新工程计划项目“延长难采储量有效动用开发技术研究” 2016KTCL01-12

详细信息

作者简介:
梁卫卫(1987—)，男，硕士，高级工程师，从事油藏地质建模及数值模拟研究。E-mail: 510741536@qq.com

通讯作者:
党海龙(1971—)，男，博士，教授级高级工程师，从事低渗透油藏开发理论与技术研究工作。E-mail: danghl@yeah.net

中图分类号: TE348
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- 被引次数: 0
出版历程
- 收稿日期: 2022-11-29
- 修回日期: 2023-04-02
- 刊出日期: 2023-05-28

Experiment and numerical simulation of water injection induced dynamic fractures in ultra-low permeability reservoirs

LIANG Weiwei^{1, 2
,},
DANG Hailong^{1, 2
, ,},
LIU Bin^{1, 2},
ZHANG Tianlong^{1, 2},
WANG Xiaofeng^{1, 2},
HOU Binchi^{1, 2},
CUI Pengxing^{1, 2},
WANG Qian^{1, 2},
ZHANG Fengyuan³

1.
Research Institute of Shaanxi Yanchang Petroleum (Group) Co., Ltd., Xi'an, Shaanxi, 710065, China
2.
Ultra-low Permeability Oil and Gas Exploration and Development Engineering Research Center of Shaanxi Province, Xi'an, Shaanxi, 710065, China
3.
School of Petroleum Engineering, China University of Petroleum (Beijing), Beijing 102249, China

摘要

摘要: 为了进一步明确特低渗透油藏注水诱导动态裂缝形成机理及其对特低渗透油藏注水开发的影响，基于注水诱导动态裂缝室内实验，阐述了注水诱导动态裂缝成因机理及延伸过程，建立了注水诱导动态裂缝数值表征方法并进行了相对应的油藏数值模拟研究。注水诱导动态裂缝按照成因主要分为天然闭合型、人工压裂诱导型和超储层破裂压力型3类。注水诱导动态裂缝生长机理主要为注入压力与岩石破裂压力或裂缝延伸压力的反复作用促使岩石发育裂缝或使已存在的裂缝不断延伸。改进的注水诱导动态裂缝实验表明，注入压力呈现反复的“升—降”特征，且注入压力是岩石产生注水诱导动态裂缝的主控参数。注水诱导动态裂缝数值模拟结果也验证了注入井井底压力呈现周期性“憋压上升—起裂下降”趋势。诱导动态裂缝产生后，裂缝体系内的压力和饱和度场是随着动态裂缝的开启和延伸而动态变化的，且沿裂缝体系变化明显，裂缝系统两侧波及范围小。
- 注水诱导动态裂缝 /
- 成因机理 /
- 室内实验 /
- 诱导裂缝数值表征 /
- 油藏数值模拟 /
- 特低渗透油藏
Abstract: In order to further clarify the mechanism of water injection induced dynamic fractures in ultra-low permeability reservoirs and its influence on water injection development in ultra-low permeability reservoirs, the genetic mechanism and propagation process of dynamic fractures induced by water injection were expounded based on the laboratory experiments of water injection induced dynamic fractures. A numerical characterization method of water injection induced dynamic fractures was established, and the corresponding reservoir numerical simulation was researched. The results indicate that the water injection induced dynamic fractures include natural closure type, artificial fracturing induced type and super reservoir breakdown pressure type. The main growth mechanism of water injection induced dynamic fractures was that the continuous extension of the fractures developed in rocks or the existing fractures through repeated action of injection pressure and rock breakdown pressure or fracture propagation pressure. The improved water injection induced dynamic fracture experiment shows that the injection pressure presents the characteristics of repeated "up and down", and the injection pressure is the main controlling parameter for the rock to generate water injection induced dynamic fractures. The numerical simulation results verify that the bottom hole pressure of the injection well shows a periodic trend of "pressure-build rise and crack initiation drop". After the dynamic fracture was induced, the pressure and saturation fields in the fracture system change dynamically with the opening and extension of the dynamic fracture and the changes are mainly obvious along the fracture system, and the influence range on both sides of the fracture system is small.
- water injection induced dynamic fracture /
- genetic mechanism /
- laboratory experiment /
- numerical characterization of induced fracture /
- reservoir numerical simulation /
- ultra-low permeability reservoir

HTML全文

图 1 鄂尔多斯盆地延长油田西部油区岩样注入压力与注入速度之间的关系

Figure 1. Relationship between injection pressure and rate of rock samples in western oil region of Yanchang oilfield, Ordos Basin

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图 2 鄂尔多斯盆地延长油田西部油区岩样注入压力与注入速度之间的关系曲线

Figure 2. Relationship between injection pressure and rate of rock samples in western oil region of Yanchang oilfield, Ordos Basin

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图 3 鄂尔多斯盆地延长油田西部油区岩心注入PV数与注入压力的关系

Figure 3. Relationship between injection PV number and pressure of rock samples in western oil region of Yanchang oilfield, Ordos Basin

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图 4 鄂尔多斯盆地延长油田西部油区长6油藏注水指示曲线

Figure 4. Water injection index curves of Chang-6 reservoir in western oil region of Yanchang oilfield, Ordos Basin

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图 5 考虑注水诱导动态裂缝的单一注采连线模型

Figure 5. Single injection-production connection model considering water injection induced dynamic fractures

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图 6 低渗透油藏注水诱导动态裂缝扩展模型

Figure 6. Propagation model of water injection induced dynamic fractures in ultra-low permeability reservoirs

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图 7 鄂尔多斯盆地志丹地区Z147-7井组注入井井底压力特征

Figure 7. Bottom hole pressure characteristics of injection well in Z147-7 well group, Zhidan area, Ordos Basin

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图 8 鄂尔多斯盆地志丹地区Z147-7井组注入井不同注水时刻压力场

Figure 8. Pressure field diagram of injection well at different water injection times of Z147-7 well group, Zhidan area, Ordos Basin

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图 9 鄂尔多斯盆地志丹地区Z147-7井组注入井不同注水时刻饱和度场

Figure 9. Saturation field diagram of injection well at different water injection times of Z147-7 well group, Zhidan area, Ordos Basin

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表 1 鄂尔多斯盆地延长油田西部油区三叠系延长组岩心基础实验数据

Table 1. Core basic experimental data of Triassic Yanchang Formation in western oil region of Yanchang oilfield, Ordos Basin

油层组	深度/m	样品编号	样品长度/cm	样品体积/cm³	孔隙体积/cm³	孔隙度/%	渗透率/10^-3μm²	储层物性
长6	1 264.8	Z1	7.03	32.69	4.81	14.7	0.56	低孔、超低渗
	1 299.3	Z2	6.85	23.27	1.86	8.0	0.32	特低孔、超低渗
	1 529.2	Z3	7.04	32.49	3.60	11.1	0.36	低孔、超低渗
长8	2 492.6	D1	7.04	31.92	3.58	11.2	0.18	低孔、超低渗
	2 493.1	D2	7.03	31.83	3.62	11.4	0.16	低孔、超低渗
	2 424.1	D3	7.04	32.24	3.03	9.4	0.09	特低孔、超低渗
长9	2 218.8	W1	7.02	32.67	4.31	13.2	0.18	低孔、超低渗
	2 080.3	W2	6.18	28.92	3.88	13.4	0.15	低孔、超低渗
	2 080.6	W3	3.73	19.49	2.65	13.6	0.12	低孔、超低渗

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表 2 鄂尔多斯盆地延长油田西部油区岩心注水诱导动态裂缝起裂次数与累计注入PV数统计

Table 2. Statistics of initiation times and cumulative injection PV number of water injection induced dynamic fractures in western oil region of Yanchang oilfield, Ordos Basin

岩心编号	起裂次数	累计注入体积/cm³	累计注入PV数
Z2	1	2.8	1.51
	2	4.6	2.47
	3	9.8	5.27
W1	1	6.3	1.45
W2	1	3.0	0.77

下载: 导出CSV

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