A predictive in-situ stress model has been built using finite- element techniques for salt enclosed stringers located in the South Oman Salt Basin. The stringers comprise silicilyte reservoir and shale formation layers, in a semi-thrustlike configuration. The model provides input and support to the fracture distribution and the compaction assessment of the silicilyte reservoirs. The model has been build based on seismic, gravity and well data.
Before building the in-situ stress model, two series of sensitivity analyses have been carried out concerning the geometrical parameters that influence the stress distribution and stability of in salt enclosed stringers. In the first analysis, the dominating parameters in an environment with an active rising salt dome (halokinesis) have been investigated. This analysis improved the motivation for the kinematic and geological development of the structures. In a second analysis, the stability of a single dipping stringer in a stationary salt body was investigated. The latter configuration is concordant with the current situation in the South Oman Sat Basin. The outcome of this analysis provided insight into the stress distribution of sinking stringers encased in salt. The insights obtained from these analyses were incorporated into the in-situ stress model.
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