Open Access

ARTICLE

Geostress Evolution and Construction Parameter Optimization in Shale Gas Infill Well Development

Yongjun Xiao¹, Yuduo Sun^2,*, Jian Zheng¹, Xiaojin Zhou³, Wang Liu¹, Cheng Shen², Qi Deng², Hao Zhao⁴
1 Sichuan Changning Natural Gas Development Co., Ltd., PetroChina Southwest Oil and Gas Field Company, Chengdu, 610056, China
2 Shale Gas Research Institute of PetroChina Southwest Oil & Gasfield Company, Chengdu, 610056, China
3 Engineering Technology Department of PetroChina Southwest Oil & Gasfield Company, Chengdu, 610056, China
4 Development Divisiont of PetroChina Southwest Oil & Gasfield Company, Chengdu, 610056, China
* Corresponding Author: Yuduo Sun. Email:
(This article belongs to the Special Issue: Enhanced Oil and Gas Recovery in Unconventional Reservoirs)

Energy Engineering https://doi.org/10.32604/ee.2025.070942

Received 28 July 2025; Accepted 23 September 2025; Published online 30 October 2025

Abstract

The shale gas development in China faces challenges such as complex reservoir conditions and high development costs. Based on the pore pressure and geostress coupling theory, this paper studies the geostress evolution laws and fracture network characteristics of shale gas infill wells. A mechanism model of CN platform logging data and geomechanical parameters is established to simulate the influence of parent well’s production on the geostress in the infill well area. It is suggested that with the increase of production time, normal fault stress state and horizontal stress deflection will occur. The smaller the parent well spacing and the longer the production time, the earlier the normal fault stress state appears and the larger the range. Based on the model, the fracture network morphology and construction parameters of infill wells are optimized.parentparentparentparent The results indicate that: 1: A well spacing of 500 m achieves a Pareto optimum between “full reserve coverage” and “stress barrier”; 2: A parent well recovery degree of 30% corresponds to the critical point of stress reversal, where the lateral deflection rate of the infill fracture is less than 8% and the SRV loss is minimized; 3: 6-cluster intensive completion with twice the liquid intensity increases the fracture complexity index by 1.7 times, enhances well group EUR by 15.4%, and reduces single-well cost by 22%. This research fills the theoretical gap in the collaborative optimization of “multi-parameter, multi-objective and multi-constraint” and provide parameter optimization basis for shale gas infill well development in China and help to improve the development efficiency and economic benefits.

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Keywords

Shale gas; horizontal well; geostress evolution; infill well development; numerical simulation; construction parameter optimization

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