Case Study of a Novel Hydraulic Fracturing Method That Maximizes Effective Hydraulic Fracture Length

Low-Cost Measurement of Hydraulic Fracture Dimensions Using Pressure Data in Treatment and Observation Wells – A Workflow for Every Well

10.2118/204183-ms ◽

2021 ◽

Author(s):

A. Kirby Nicholson ◽

Robert C. Bachman ◽

R. Yvonne Scherz ◽

Robert V. Hawkes

Keyword(s):

Hydraulic Fracturing ◽

Real Time ◽

Hydraulic Fracture ◽

Full Scale ◽

Pressure Data ◽

Observation Well ◽

High Quality ◽

Fracture Length ◽

Geometry Model ◽

Observation Wells

Abstract Pressure and stage volume are the least expensive and most readily available data for diagnostic analysis of hydraulic fracturing operations. Case history data from the Midland Basin is used to demonstrate how high-quality, time-synchronized pressure measurements at a treatment and an offsetting shut-in producing well can provide the necessary input to calculate fracture geometries at both wells and estimate perforation cluster efficiency at the treatment well. No special wellbore monitoring equipment is required. In summary, the methods outlined in this paper quantifies fracture geometries as compared to the more general observations of Daneshy (2020) and Haustveit et al. (2020). Pressures collected in Diagnostic Fracture Injection Tests (DFITs), select toe-stage full-scale fracture treatments, and offset observation wells are used to demonstrate a simple workflow. The pressure data combined with Volume to First Response (Vfr) at the observation well is used to create a geometry model of fracture length, width, and height estimates at the treatment well as illustrated in Figure 1. The producing fracture length of the observation well is also determined. Pressure Transient Analysis (PTA) techniques, a Perkins-Kern-Nordgren (PKN) fracture propagation model and offset well Fracture Driven Interaction (FDI) pressures are used to quantify hydraulic fracture dimensions. The PTA-derived Farfield Fracture Extension Pressure, FFEP, concept was introduced in Nicholson et al. (2019) and is summarized in Appendix B of this paper. FFEP replaces Instantaneous Shut-In Pressure, ISIP, for use in net pressure calculations. FFEP is determined and utilized in both DFITs and full-scale fracture inter-stage fall-off data. The use of the Primary Pressure Derivative (PPD) to accurately identify FFEP simplifies and speeds up the analysis, allowing for real time treatment decisions. This new technique is called Rapid-PTA. Additionally, the plotted shape and gradient of the observation-well pressure response can identify whether FDI's are hydraulic or poroelastic before a fracture stage is completed and may be used to change stage volume on the fly. Figure 1Fracture Geometry Model with FDI Pressure Matching Case studies are presented showing the full workflow required to generate the fracture geometry model. The component inputs for the model are presented including a toe-stage DFIT, inter-stage pressure fall-off, and the FDI pressure build-up. We discuss how to optimize these hydraulic fractures in hindsight (look-back) and what might have been done in real time during the completion operations given this workflow and field-ready advanced data-handling capability. Hydraulic fracturing operations can be optimized in real time using new Rapid-PTA techniques for high quality pressure data collected on treating and observation wells. This process opens the door for more advanced geometry modeling and for rapid design changes to save costs and improve well productivity and ultimate recovery.

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High-Resolution 3D Structural Geomechanics Modeling for Hydraulic Fracturing

10.2118/spe-173362-ms ◽

2015 ◽

Author(s):

T.. Bérard ◽

J.. Desroches ◽

Y.. Yang ◽

X.. Weng ◽

K.. Olson

Keyword(s):

High Resolution ◽

Stress Field ◽

Hydraulic Fracturing ◽

Hydraulic Fracture ◽

Three Dimensional ◽

Image Data ◽

Natural Fractures ◽

Fracture Length ◽

3D Space ◽

Wellbore Pressure

Abstract Three-dimensional (3D) geomechanical models built at reservoir scale lack resolution at the well sector scale (e.g., hydraulic fracture scale), at least laterally. One-dimensional (1D) geomechanical models, on the other hand, have log resolution along the wellbore but no penetration away from it—along the fracture length for instance. Combining borehole structural geology based on image data and finite elements (FE) geomechanics, we constructed and calibrated a 3D, high-resolution geomechanical model, including subseismic faults and natural fractures, over a 1,500- × 5,200- × 300-ft3 sector around a vertical pilot and a 3,700-ft lateral in the Fayetteville shale play. Compared to a 1D approach, we obtained a properly equilibrated stress field in 3D space, in which the effect of the structure, combined with that of material anisotropy and heterogeneity, are accounted for. These effects were observed to be significant on the stress field, both laterally and local to the faults and natural fractures. The model was used to derive and map in 3D space a series of geomechanically based attributes potentially indicative of hydraulic fracturing performance and risks, including stress barriers, fracture geometry attributes, near-well tortuosity, and the level of stress anisotropy. An interesting match was observed between some of the derived attributes and fracturing data—near-wellbore pressure drop and overall ease and difficulty to place a treatment—encouraging their use for perforation and stage placement or placement of the next nearby lateral. The model was also used to simulate hydraulic fracturing, taking advantage of such a 3D structural and geomechanical representation. It was shown that the structure and heterogeneity captured by the model had a significant impact on hydraulic fracture final geometry.

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Experimental and Numerical Simulation Study of Hydraulic Fracture Propagation during Coalbed Methane Development

Geofluids ◽

10.1155/2021/3632997 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Qingshan Ren ◽

Yaodong Jiang ◽

Pengpeng Wang ◽

Guangjie Wu ◽

Nima Noraei Danesh

Keyword(s):

Numerical Simulation ◽

Hydraulic Fracturing ◽

Hydraulic Fracture ◽

Coalbed Methane ◽

Fracture Propagation ◽

Fractured Reservoir ◽

Natural Fractures ◽

Fracture Length ◽

Coalbed Methane Reservoir ◽

Hydraulic Fracture Propagation

The extraction of low-permeability coalbed methane (CBM) has the dual significance of energy utilization and safe mining. Understanding hydraulic fracturing mechanism is vital to successful development of CBM. Therefore, it is important to improve the law of hydraulic fracture propagation in coal and rigorously study the influencing factors. In this paper, laboratory experiments and numerical simulation methods were used to investigate the hydraulic fracture propagation law of coal in coalbed methane reservoir with natural fractures. The results show that the maximum and minimum horizontal in situ stress and the difference in stress significantly affect the direction of crack propagation. The elastic modulus of coal, the mechanical properties of natural fractures, and the injection rate can affect the fracture length, fracture width, and the amount of fracturing fluid injected. To ensure the effectiveness of hydraulic fracturing, a reservoir environment with a certain horizontal stress difference under specific reservoir conditions can ensure the increase of fractured reservoir and the controllability of fracture expansion direction. In order to increase the volume of fractured reservoir and fracture length, the pumping speed of fracturing fluid should not be too high. The existence of stress shadow effect causes the hydraulic fracture to propagate along the main fracture track, where the branch fracture cannot extend too far. Complex fractures are the main hydraulic fracture typology in coalbed methane reservoir with natural fractures. The results can provide a benchmark for optimal design of hydraulic fracturing in coalbed methane reservoirs.

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Experimental Study of Hydraulic Fracturing in an Impermeable Material

Journal of Energy Resources Technology ◽

10.1115/1.3230889 ◽

1983 ◽

Vol 105 (2) ◽

pp. 116-124 ◽

Cited By ~ 17

Author(s):

M. B. Rubin

Keyword(s):

Experimental Data ◽

Hydraulic Fracturing ◽

Hydraulic Fracture ◽

Critical Parameters ◽

Laboratory Model ◽

Finite Width ◽

Fracture Width ◽

Fracture Length ◽

Numerical Predictions ◽

Fluid Leak

A laboratory experiment was conducted to study hydraulic fracturing in an impermeable material (PMMA). Quantitative experimental data were obtained to compare with numerical predictions for a simple hydraulic fracture treatment that is not complicated by the effects of fluid leak-off and proppant transport. The borehole pressure, the pressure in the fracture at three locations, the fracture width at one location, and the fracture length were measured as functions of time during propagation of a vertically contained hydraulic fracture. The experimental data are compared with the predictions of simple solutions and the results indicate that when the finite width of the laboratory model is included in the analysis, the comparison between theory and experiment is quite good. The results also indicate that the assumption of a uniform pressure distribution in the fracture is adequate to accurately predict the critical parameters (fracture width and length) even when the fracturing fluid is very viscous.

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Numerical Simulation of Hydraulic Fracture Propagation Characteristics of Low Permeable Coal-Rock Mass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.1668 ◽

2012 ◽

Vol 482-484 ◽

pp. 1668-1671 ◽

Cited By ~ 1

Author(s):

Zhi Gang Yuan ◽

Hong Tu Wang ◽

Nian Ping Liu

Keyword(s):

Rock Mass ◽

Hydraulic Fracturing ◽

Hydraulic Fracture ◽

Fracture Propagation ◽

Injection Pressure ◽

Horizontal Stress ◽

Propagation Model ◽

Fracture Length ◽

Coal Rock ◽

Hydraulic Fracture Propagation

Based on the coal-rock mass deformation model, hydraulic pressure descent model in fracture, fracture propagation model and its growth criterion, the mathematical model of hydraulic fracturing of low permeable coal-rock mass is established, and the influencing factors such as injection pressure, elastic modulus of coal-rock mass and in-situ stress, which affect the characteristics of hydraulic fracture propagation, are studied using the ANSYS software. The results show that fracture length presents a linear increase and widest width increases as an exponent function with the increase of injection pressure, and the ability of making fracture width is greater than fracture length during late fracturing; besides, with the increase of Young’s modulus of coal-rock mass and least horizontal stress, fracture length and widest width decrease, which are independent of maximum horizontal stress. The obtained conclusions provide a guiding role for the optimization of operation parameters of field hydraulic fracturing of low permeable coal-rock.

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