Investigating local stress variations inferred from earthquake properties in proximity to a hydraulic fracture well.

非常规油气生产商的主要目标是以最小的成本开采碳氢化合物

The primary goal of non-conventional oil and gas producers is to recover hydrocarbons with the minimum required effort. Well productivity is a key factor influencing the efficiency and profitability in oil or gas recovery. Local geologic structure, such as faults, can influence the productivity of hydraulic fracturing wells. Productivity is strongly linked to the appearance of the fracture network formed during the fracture process, i.e., whether fractures are distributed in space, or concentrated into broad, planar features. Proximity to faults can change the appearance of the network of fractures formed during the fracturing process, however, the relationship between fault distance and the fracture network is poorly understood. Here we will study the migration of fluids through the fracture network creating during well production to learn what the nearby earthquakes can tell us about the stress field in which the fractures form. We will use the earthquake source properties to help constrain the local variations in the stress field, and compare the variations with the location of known faults. We will then examine the relationship between the stress field and the fracture network related to hydraulic fracturing to try and infer how the stress field influences the appearance of the fracture network, i.e., well productivity. The information on stress field and well productivity for this case study can then be directly used by the company, Progress Energy Canada, Ltd. to select the optimal sites for drilling a future well. This project will directly benefit Progress Energy by helping them increase well productivity, as well benefit the Canadian economy as the second largest exporter of natural gas.