Far-field strain analysis for fiber optic monitoring of hydraulic fracturing in a deep naturally fractured shale reservoir

被引：0

作者：

Sang, Yu ^{[1
]}

Sui, Weibo ^{[2
]}

Zeng, Bo ^{[3
]}

Song, Yi ^{[3
]}

Huang, Haoyong ^{[3
]}

Guo, Huan ^{[2
]}

Yang, Yanming ^{[2
]}

Song, Jiayi ^{[2
]}

Du, Guanghao ^{[2
]}

机构：

[1] PetroChina Southwest Oil & Gasfield Company, Sichuan, Chengdu

[2] College of Petroleum Engineering, China University of Petroleum - Beijing, Beijing

[3] Shale Gas Research Institute, PetroChina Southwest Oil & Gasfield Company, Sichuan, Chengdu

来源：

Natural Gas Industry | 2024年 / 44卷 / 05期

关键词：

Casing deformation; DAS; Deep shale gas; Far-field strain; Fracture communication; Hydraulic fracturing; Natural fracture; Southern Sichuan Basin;

D O I：

10.3787/j.issn.1000-0976.2024.05.005

中图分类号：

学科分类号：

摘要：

Deep shale reservoirs (burial depth greater than 4 000 m) in the southern Sichuan Basin (hereafter referred to as southern Sichuan) are characterized by developed natural fractures and complex in-situ stress distribution. Casing deformation and other problems in the process of hydraulic fracturing restrict the efficient development of shale gas resources severely. To monitor the far-field strain during the fracturing of natural fractures in deep shale reservoirs, this paper applies the offset-well DAS strain monitoring technology to monitor the zipper fracturing process of two wells on the Platform A in the Luzhou Block. And then, the monitoring results are analyzed and discussed on the basis of the fracturing design and reservoir characteristics. And the following results are obtained. First, the 300–350 m monitoring well spacing and the pumping-type inside-casing optical fiber layout can provide a lot of favorable data for the assessment of far-field fracture communication and evolution, but less information for the main stimulated regions of a fractured well. Second, during the fracturing of different wells on the same platform, the response of far-field strain may be quite large. The fracturing parameter design of high-risk wells usually play a key role in the communication of far-field fractures, while low-risk wells mainly show a following role. Once a fracture communication region is formed, it is very likely to evolve into the common fracture communication region of two fractured wells. Third, the response region of far-field strain and the current fracturing stage may differ in location by 200–300 m. The strain communication region between different stages of the same well may be formed in advance, and it may be 400–500 m from the current fracturing stage. Fourth, the far-field fractures formed by fracturing the natural fractures in deep shale reservoirs present completely new morphological characteristics, including universal inclined fractures and horizontal bedding-parallel fractures near the flexural section. In conclusion, the DAS strain monitoring technology provides a new method for analyzing the evolution of far-field strain during the fracturing of natural fractures in deep shale reservoirs. And combined with geology-engineering integrated fracturing design scheme and casing deformation mechanism and prevention research, it is expected to assist the large-scale benefit development of deep shale gas in the southern Sichuan. © 2024 Natural Gas Industry Journal Agency. All rights reserved.

引用

页码：56 / 67

页数：11

共 42 条

[31]

LIU Yongzan, WU Kan, JIN Ge, Et al., Rock deformation and strain-rate characterization during hydraulic fracturing treatments: Insights for interpretation of low-frequency distributed acoustic-sensing signals, SPE Journal, 25, 5, pp. 2251-2264, (2020)

[32]

WANG Jiehao, TAN Yunhui, RIJKEN M, Et al., Observations and deformation in horizontal wells for shale gas in Sichuan, West-China Exploration Engineering, 35, 2, pp. 44-48, (2023)

[33]

WU Jianfa, ZHANG Chenglin, ZHAO Shengxian, Et al., Typical types of shale gas reservoirs in southern Sichuan Basin and enlightenment of exploration and development, Natural Gas Geoscience, 34, 8, pp. 1385-1400, (2023)

[34]

ZHAO Shengxian, XIA Ziqiang, LI Hai, Et al., Quantitative evaluation and main controlling factors of natural fractures in a shale reservoir: A case study of the deep shale of the Wufeng Formation-Longmaxi Formation in Luzhou, Acta Sedimentologica Sinica, pp. 1-17

[35]

HAN Lingling, LI Xizhe, LIU Zhaoyi, Et al., Influencing factors and prevention measures of casing deformation in deep shale gas wells in Luzhou Block, southern Sichuan Basin, SW China, Petroleum Exploration and Development, 50, 4, pp. 853-861, (2023)

[36]

LI Fanhua, DONG Kai, FU Pan, Et al., Prediction and control of casing damage in large volume fracturing of horizontal gas wells, Natural Gas Industry, 39, 4, pp. 69-75, (2019)

[37]

WANG Leding, WEI Shubao, HUAI Qiaoshuang, Et al., Mechanism, countermeasure research, and application of casing

[38]

WANG Zhiping, ZHANG Qing, LIU Ziping, Et al., Efficient development technology slope-type strongly heterogeneous shale gas reservoirs: A case study on the Longmaxi Formation shale gas eservoir in the Weiyuan area of the southern Sichuan Basin, Natural Gas Industry, 41, 4, pp. 72-81, (2021)

[39]

ZHANG Ping, HE Yunbin, LIU Ziping, Et al., Shear compression deformation test and deformation prevention practice of casing in shale gas horizontal wells, Natural Gas Industry, 41, 5, pp. 84-91, (2021)

[40]

WANG Wendong, YU Wenfeng, GAO Pan, Et al., Mechanisms and impact patterns of frac hits between shale gas wells, Natural Gas Industry, 44, 1, pp. 128-138, (2024)

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