EXTRAPOLATING FRACTURE ORIENTATIONS FROM HORIZONTAL WELLS USING STRESS TRAJECTORY MODELS

This paper presents a recently developed approach for extrapolating fr acture orientations from horizontal wells. It is commonly accepted tha t tension fractures propagate perpendicular to the minimum principal s tress. The hypothesis has been tested that in some cases, by modelling the stress trajectories within a faulted compartment, it is possible to reproduce the orientations of the tension fractures. The stress tra jectory models we present are based on photo-elastic techniques. The m odels are first calibrated against outcrop fracture patterns and are s ubsequently applied to a reservoir database consisting of a 3D seismic block and a horizontal well with almost complete FMS image coverage. The results show that tension fractures may show perturbed orientation s in the vicinity of faults. It is shown that by appropriate character ization of the seismic and well fracture data, it may be possible to u se stress trajectory models to predict fracture orientation in a reser voir.