Laboratory hydraulic fracturing experiments in intact and pre-fractured rock

doi:10.1016/0148-9062(77)90196-6

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts

Volume 14, Issue 2, March 1977, Pages 49-58

International Journa...

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Abstract

Laboratory hydraulic fracturing experiments were conducted to investigate two factors which could influence the use of the hydrofrac technique for in-situ stress determinations; the possible dependence of the breakdown pressure upon the rate of borehole pressurization, and the influence of pre-existing cracks on the orientation of generated fractures. The experiments have shown that while the rate of borehole pressurization has a marked effect on breakdown pressures, the pressure at which hydraulic fractures initiate (and thus tensile strength) is independent of the rate of borehole pressurization when the effect of fluid penetration is negligible. Thus, the experiments indicate that use of breakdown pressures rather than fracture initiation pressures may lead to an erroneous estimate of tectonic stresses. A conceptual model is proposed to explain anomalously high breakdown pressures observed when fracturing with high viscosity fluids. In this model, initial fracture propagation is presumed to be stable due to large differences between the borehole pressure and that within the fracture. In samples which contained pre-existing fractures which were ‘leaky’ to water, we found it possible to generate hydraulic fractures oriented parallel to the direction of maximum compression if high viscosity drilling mud was used as the fracturing fluid.

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C.B. Raleigh et al.
Faulting and crustal stress at Rangely, Colorado
Flow and Fracture of Rocks
(1972)
B. Haimson
Earthquake related stresses at Rangely, Colorado
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Hydraulic fracturing stress measurements near the Hohenzollerngraben-structure
Pageoph.
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Mechanics of hydraulic fracturing
Trans. Am. Inst. Min. Engrs
(1957)
R.O. Kehle
The determination of tectonic stresses through analysis of hydraulic well fracturing
J. Geophys. Res.
(1964)
B. Haimson
Hydraulic fracturing in porous and non-porous rock and its potential for determining in-situ stress at depth

There are more references available in the full text version of this article.

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International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts

Abstract

References (13)

Faulting and crustal stress at Rangely, Colorado

Flow and Fracture of Rocks

Earthquake related stresses at Rangely, Colorado

Hydraulic fracturing stress measurements near the Hohenzollerngraben-structure

Pageoph.

Mechanics of hydraulic fracturing

Trans. Am. Inst. Min. Engrs

The determination of tectonic stresses through analysis of hydraulic well fracturing

J. Geophys. Res.

Hydraulic fracturing in porous and non-porous rock and its potential for determining in-situ stress at depth

Cited by (297)

Experimental research of novel true triaxial hydrothermal phase change impact fracturing

A multiscale poroelastic damage model for fracturing in permeable rocks

Single fluid-driven crack propagation in analogue rock assisted by chemical environment

Combined effects of bedding anisotropy and matrix heterogeneity on hydraulic fracturing of shales from Changning and Lushan, South China: An experimental investigation

Characteristics of carbon dioxide fracturing in comparison to conventional water hydraulic fracturing: Evidence from acoustic emission monitoring of small-scale field experiments

Impacts of wellbore orientation with respect to bedding inclination and injection rate on laboratory hydraulic fracturing characteristics of Lushan shale