Hydraulic fracturing induced fault slip and casing shear in Sichuan Basin: A multi-scale numerical investigation

Zhang, Fengshou; Jiang, Zhenyuan; Chen, Zhaowei; Yin, Zirui; Tang, Jizhou

doi:10.1016/j.petrol.2020.107797

Cited by 31 publications

(6 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generally speaking, the lower the elastic modulus of the cement sheath, the better the compressibility of the cement sheath. However, studies have shown that even with a lower elastic modulus, the compressibility of the cement sheath is still relatively small [24]. Moreover, it is not possible to infinitely decrease the elastic modulus of the cement sheath.…”

Section: Casing Deformation Prevention Based On Cement System Optimiz...mentioning

confidence: 99%

A Study on the Mechanism of Casing Deformation and Its Control Strategies in Shale Oil Hydraulic Fracturing

Zhang

Wang

et al. 2023

Processes

View full text Add to dashboard Cite

The problem of casing deformation caused by large-scale hydraulic fracturing in shale oil wells severely restricts the efficient development of Gulong shale oil. In order to clarify the mechanism of casing deformation in shale oil wells, comprehensive analysis was conducted on engineering factors, multi-arm caliper logging, seismic attributes, and the distribution characteristics of casing deformations. This study shows that casing strength, cementing quality, and wellbore curvature are not the main controlling factors for casing deformation. Casing deformation is caused by the communication between hydraulic fractures and natural fractures during the fracturing process, which increases the fluid pressure in the natural fracture and induces shear slip, resulting in casing deformation due to shear stress. Based on the understanding of the mechanism of casing deformation in shale oil wells, two targeted casing deformation prevention and control methods are proposed. First, temporary plugging was implemented during the hydraulic fracturing process when the fluid volume reached 1000 m3, and the pumping rate was reduced to below 16 m3/min to reduce the internal fluid pressure of the fractures and control fracture slip, thereby minimizing the risk of casing deformation. Second, hollow particles were added to the cement to enhance the consolidation effect of the cement sheath and mitigate casing deformation caused by fracture slip. Research indicates that a hollow particle content of 15% can meet the requirements for casing deformation control in Gulong shale oil. These research results can provide important references for the prediction and prevention of casing deformation risks in shale oil and similar unconventional reservoirs during hydraulic fracturing.

show abstract

Section: Casing Deformation Prevention Based On Cement System Optimiz...mentioning

confidence: 99%

A Study on the Mechanism of Casing Deformation and Its Control Strategies in Shale Oil Hydraulic Fracturing

Zhang

Wang

et al. 2023

Processes

View full text Add to dashboard Cite

show abstract

“…Nevertheless, most existing large-scale fracturing models assume that the mechanical properties of the reservoir rocks are homogeneous. This assumption helps simplify the problem and realize large-scale fracturing simulation. − However, this assumption ignores the effect of the stratum property difference on the fracture propagation. It is well-known that the stratum property difference significantly affects the behavior of hydraulic fracture propagation in low-permeability reservoirs, such as the fracture propagation range, breakdown pressure, and interaction between wells. , Therefore, the establishment of a large-scale layered model, which can accurately characterize stratum properties, is of great importance for the study of hydraulic fracture propagation mechanisms in low-permeability reservoirs.…”

Section: Introductionmentioning

confidence: 99%

Mechanisms of Hydraulic Fracture Propagation and Multi-well Effect during Multiple Vertical Well Fracturing in Layered Reservoirs with Low Permeability

Yang,

Li,

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

Segmental-layered modeling and fine grid division methods were proposed to construct a three-dimensional largescale layered geologic model and reveal the mechanisms of hydraulic fracture propagation and the well spacing effect in multi-well fracturing in layered reservoirs with low permeability. The hydraulic fracture propagation in layered reservoirs under multi-well fracturing was simulated using a continuum-based discrete element numerical method. The effects of the stratum property difference, in situ horizontal stress difference (HSD), and well spacing on breakdown pressures and fracture propagation were analyzed. The concept of "extension ellipse" was proposed to describe the propagation morphology of fractures, which addresses the difficulty of accurately characterizing the propagation morphology of fractures at the geologic scale. The influence range of the multiwell effect in layered reservoirs was also determined, and the effect mechanisms of stress amplification and attraction and repulsion between fractures on the behavior of hydraulic fracture propagation were revealed. Layered reservoirs and higher in situ HSD restrict the development of hydraulic fractures but greatly reduce the breakdown pressures. The multi-well fracturing mode changes the stress field distribution around the wells and weakens the effects of in situ HSD on fracture propagation. In comparison to homogeneous reservoirs, the range of the multi-well effect in the layered reservoirs is relatively small. At the fracturing site, the well spacing should be appropriately increased in the direction of the maximum horizontal stress and should be reduced in the direction of minimum horizontal stress, helping hydraulic fracture development and improving the fracturing stimulation effect in layered reservoirs. This study addresses the deficiency of considering stratum property differences in the existing large-scale fracturing models, and the results provide a reference for the optimization and design of fracturing simulation in the layered reservoirs with low permeability.

show abstract

“…Nevertheless, the maximum casing curvature is merely reduced by 8% (Gao et al 2017;Yin et al, 2018c;Lu et al, 2021), and casing deformation still occurs in seven out of eight test wells. ②According to the geological model, the fracturing engineer simulated the effects of fault activation and bedding plane hydration expansion on fracturing treatment (McClure and Horne, 2011;Rutqvist et al, 2015;Zhang et al, 2020a, Zhang et al, 2020bZhang Xin et al, 2021;Li J. et al, 2021;, high-density completion, reduction in the fracturing fluid volume and treatment rate, compound temporary plugging technique have been used to reducing the activity of the fracture system. Nevertheless, these approaches are still ineffective in the study area (Zhang X. et al, 2021;Tong et al, 2021b;Zhang P. et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

Casing Deformation Response and Controlling Technology Based on Diagnostics of Shale Gas Fracturing Curve

Cheng¹,

Zeng²,

Wu³

et al. 2022

Front. Energy Res.

View full text Add to dashboard Cite

Casing deformation (CD) will seriously affect the fracturing progress and stimulation effect of shale gas. Taking 105 gas wells in the Luzhou shale gas area in southern Sichuan as an example, the CD prediction model was established by introducing the fracture operation curve diagnosis method to analyze the changes in net pressure and propagation mode during fracturing. The fracturing stage induced by CD is called the excited (ET) stage, and the fracturing stage that occurs during CD is called the CD stage. It is concluded that the change of net pressure and the propagation mode are coupled with each other. By natural fracture development, formation curvature and horizontal well trajectory, natural fractures and bedding have been active by high fracturing strength, or because of the frequent crossing-layer in single stage, local stress reverse, makes the net pressure decrease and makes the formation in strike-slip stress state to reverse fault stress state, liquid leak-off and blocked fracture propagation time are increased, thus inducing CD. According to the response law induced by CD, the CD pre-control mode is formed, and the CD pre-control technology is established to quantitatively evaluate the wellbore risk and optimize the fracturing operation order and time arrangement. The CD rate is reduced from 56% in the early stage to 20%, and the integrity of the wellbore is guaranteed to be 100%. The method has strong applicability in the field and can be further popularized.

show abstract

Hydraulic fracturing induced fault slip and casing shear in Sichuan Basin: A multi-scale numerical investigation

Cited by 31 publications

References 33 publications

A Study on the Mechanism of Casing Deformation and Its Control Strategies in Shale Oil Hydraulic Fracturing

A Study on the Mechanism of Casing Deformation and Its Control Strategies in Shale Oil Hydraulic Fracturing

Mechanisms of Hydraulic Fracture Propagation and Multi-well Effect during Multiple Vertical Well Fracturing in Layered Reservoirs with Low Permeability

Casing Deformation Response and Controlling Technology Based on Diagnostics of Shale Gas Fracturing Curve

Contact Info

Product

Resources

About