Providing confidence that hydraulic-fracture geometries are relatively confined to target coal seams and do not grow upward into beneficial groundwater aquifers is a primary concern. A hybrid downhole microseismic and microdeformation array was deployed to monitor fracture stimulation of a vertical coal-seam-gas (CSG) exploration well in the Gloucester Basin in New South Wales, Australia, to provide more-accurate insight into overall fracture height. These technologies complement each other by providing unique, far-field determinations of hydraulic-fracture geometry.
Introduction
Increasing community and regulatory concern regarding exploration and production of CSG and fracture stimulation has placed extreme constraints on titleholders in New South Wales, to the point of the government rescinding some exploration permits and titleholders nearing a halt to further exploration.
The operator is determined to provide evidence that CSG pilot exploration wells and, in particular, fracture stimulation are not affecting beneficial aquifers or interacting with faults. It is important that the operator be able to provide scientific explanations that are understandable and accessible to the community and assist in regulatory approval processes for the industry.
The primary goals of the project were to assess any fracture-height growth toward aquifers and possible interaction with surrounding faults.
