- Hydraulic Fracturing Mine Back Trials — Design Rationale and Project Status
- P.K. Kaiser ; B. Valley ; M.B. Dusseault ; D. Duff
- Book Title / Journal: Effective and Sustainable Hydraulic Fracturing
- Year: 2013 , Series: Chapter 44
- Rock Mechanics ; Mining
- Keywords: stress management ; stiffness modification ; shale gas analogue ; mine-back experiments ; naturally fractured rocks
- Last year, a joint Mining and Oil & Gas industry consortium was established in Canada to
conduct hydraulic fracturing (HF) tests accompanied by a mine-back of fractured regions to assess HF models and microseismic monitoring data during controlled experiments. Details about the displacement field, fracture aperture and extent, and micro-seismic parameters could then be verified and used as calibration data for modeling of HF processes in igneous and dense sedimentary rocks.
Various injection experiments are planned and they will include pre-fracturing rock mass
characterisation using best available current techniques, dense arrays of multi-parameter
wall and borehole-mounted instruments, and the treated volume will be mined through to
assess fracturing effectiveness, existing fractures and new fracture interactions, and to deter‐
mine if pathways can be identified for improving currently available numerical and fracture
network modeling tools.
In this paper we present the results of the experimental design and planning phase, outlin‐
ing objectives and justifications for planned experimental layouts. Preliminary plans for a
first mine-through trial at Newcrest Mining’s Cadia East mine in New South Wales, Austral‐
ia are described. The hypotheses advanced in this experimental design, supported by evi‐
dence from the literature, are that activation and development of a fracture network by
hydraulic stimulation is possible if the injection procedure is designed such that injection
pressures and rates are maintained within an optimal window, thereby producing condi‐
tions under which effective stress management for risk mitigation in deep mining can best be achieved. The evaluation of these hypotheses is the focus of the current high level experi‐
mental plan presented in the paper.