Impact of asymmetric stimulated rock volume on casing deformation in multi-stage fracturing; a case study

Hao Yu, Arash Dahi Taleghani, Zhanghua Lian, Tiejun Lin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Microseismic data and production logs in our study area have confirmed an asymmetric development of the stimulation rock volume, while severe casing deformation problems have been reported frequently in this area. In this paper, we investigate the possibility of casing failure due to strong shear stresses developed by asymmetric stimulated zones. Overlapping stimulation zones in adjacent stages may intensify asymmetry of the pore pressure distribution and resultant shear forces. Although induced shearing may have a positive impact on fracture permeability, but it may also cause operational problems by inducing severe casing deformations. While most of the casing deformation models only consider rock deformations very close to the wellbore, we developed a 3D coupled model for fracture network growth and stress redistribution during hydraulic fracturing to achieve a more realistic model for casing deformation. This reservoir-scale model is tied to a more detailed near-wellbore model including the casing and cement sheath to simulate casing deformations. Case studies were conducted using data from a shale gas well that experienced severe casing deformation during hydraulic fracturing. Impact of stage spacing, and pumping rate are incorporated to investigate their potential impacts on casing and well integrity. Multi-stage hydraulic fracturing considering the development of complex fracture network is simulated at the reservoir scale based on the microseismic events. Continuous re-distribution and re-orientation of stress field near the borehole are tracked during the development of the fracture network which reveals some pocket of tensile stresses along the casing. Asymmetric fractures are observed to generate strong shear stress on the suspended casing. These shear forces result in deflection and S-shape deformations. Some regions receive repeating treatments, which leads to increase formation stress heterogeneity and worsen casing deformation severity. Our analysis has indicated that simply increasing the flexural strength by increasing thickness of casing cannot radically mitigate casing deformation problems. This paper provides a novel workflow for a coupled modelling of casing deformation during hydraulic fracturing operations, while current modelling efforts assume symmetric fracture geometries.

Original languageEnglish (US)
Title of host publicationSociety of Petroleum Engineers - SPE Annual Technical Conference and Exhibition 2019, ATCE 2019
PublisherSociety of Petroleum Engineers (SPE)
ISBN (Electronic)9781613996638
StatePublished - Jan 1 2019
EventSPE Annual Technical Conference and Exhibition 2019, ATCE 2019 - Calgary, Canada
Duration: Sep 30 2019Oct 2 2019

Publication series

NameProceedings - SPE Annual Technical Conference and Exhibition
Volume2019-September

Conference

ConferenceSPE Annual Technical Conference and Exhibition 2019, ATCE 2019
CountryCanada
CityCalgary
Period9/30/1910/2/19

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Fuel Technology
  • Energy Engineering and Power Technology

Cite this

Yu, H., Taleghani, A. D., Lian, Z., & Lin, T. (2019). Impact of asymmetric stimulated rock volume on casing deformation in multi-stage fracturing; a case study. In Society of Petroleum Engineers - SPE Annual Technical Conference and Exhibition 2019, ATCE 2019 (Proceedings - SPE Annual Technical Conference and Exhibition; Vol. 2019-September). Society of Petroleum Engineers (SPE).