Inferring in situ stresses in a naturally fractured heavy oil field

Delineation of in situ stress field (magnitudes and orientations of the principal stresses) has several applications in petroleum industry such as better drilling management, effects of oil production on stress regime change, stress change effects on permeability, increasing the stability of boreholes, enhancing the oil production from stress sensitive reservoirs, subsidence due to stress changes, and optimal drilling and field development. In this article, magnitudes and orientations of the in situ principal stresses in the study area was estimated with combination of various available data and techniques including core analysis, image logs (FMI and UBI logs), World Stress Map, and geological and geotectonics evidences. The orientation of maximum and minimum horizontal stresses was obtained NE-SW and NW-SE. In addition, magnitudes of the in situ principal stresses and pore pressure were estimated. Estimates made in this study using multiple sources such as core analysis, and image logs are in a good agreement with estimates suggested by World Stress Map, and geological and geotectonic evidences. Results obtained from this study will help manage the geomechanical issues related to drilling and production more efficiently.