Prediction of Hydraulic Fracture Azimuth Through Geological, Core and Analytical Studies

摘要

Results of 10 different methods for determining the maximum horizontal principal stress direction at the DOE's Multi-Well Experiment site in the Piceance Basin, Colorado show remarkable consistency. The methods included surface geological observations (e.g. fracture mapping, lineament analysis, and faulting), analyses of oriented core from the Multi-Well Experiment (e.g. strain relaxation, differential strain analysis, acoustic velocity anisotropy, natural fractures), and computer modeling of expected stresses caused by topographic loads. The mean direction predicted for the maximum horizontal principal stress is N79.6 exp 0 W. The very small standard deviation about this prediction of 5.5 exp 0 indicates the extreme consistency among the methods. Similar methods could be utilized in other low permeability reservoirs to determine stress orientation and hence hydraulic fracture propagation direction. 16 figures. (ERA citation 08:017285)