Reducing Exploration and Appraisal Risk in Low Permeability Reservoirs Using Microseismic Fracture Mapping—Part 2

Abstract

AbstractThe exploration and appraisal of low-permeability or unconventional hydrocarbon resources is significantly different than conventional reservoirs; exploration is more like appraisal, requiring pilot programs to test commerciality of these plays prior to embarking upon large-scale development (Hall 2007; Stabell et al. 2007), including the effect of completion and stimulation optimization (Haskett and Brown 2005). One essential component of low-permeability reservoir development is hydraulic fracturing, which virtually all of these wells require. With the introduction of hydraulic fracture monitoring (HFM), we are now able to measure fracture geometry and complexity, which has led to major improvements in treatment designs, well completions, and field development strategies in North America. HFM applications were once focused on development and infill drilling, but they have recently shown significant value for exploration plays (primarily in gas shale). HFM measurements now allow operators to more efficiently evaluate the effectiveness of stimulation treatments and completion approaches in exploration and appraisal wells, reducing the number of wells required to assess the economic viability of low-permeability reservoirs.The application of HFM to exploration and appraisal programs outside North America could significantly accelerate the evaluation of low-permeability reservoirs, where selecting the appropriate hydraulic fracturing design and well completion strategy will be key to success. It could also accelerate the learning curve, which is essential to quickly reducing costs and improving well productivity and hydrocarbon recovery. This paper presents several case histories that illustrate the application of microseismic mapping to characterize hydraulic fracture growth and improve stimulation designs and completion strategies, and demonstrates that the limitations on well locations required to implement microseismic mapping do not significantly increase the cost of the appraisal program.