A South East Asia exploration well was drilled into a gas-bearing large anticlinal 4-way Jurassic and Triassic age continental clastic with marine incursions. The well was designed to evaluate gas in tight sandstone with fractures. The host rock overall had low matrix permeability. Conventional methods of gas production from tight reservoirs usually require artificial stimulation such as some form of hydraulic fracturing. This well was no exception.

In order to optimize the hydraulic fracture design, a 1-D geomechanics study was requested to estimate hydraulic frac-ability of the rock. A 1-D Mechanical Earth Model (MEM) was constructed and fracture breakdown pressure was estimated as an outcome of the model. Mechanical properties are derived from logs data and calibrated against core with rock mechanics test data. Advanced sonic processing conducted before and after the fracing which give estimated pre- and post hydraulic minimum and maximum horizontal stress. These data was used to calibrate horizontal stresses profiles derived using poro-elastic strain models. The shear radial profiling was carried out allowing for identifications of the existence of stress within the rock. The advanced sonic processing also revealed the characteristic of stress anisotropy in the formation. Hydraulic fracture design and procedure was then developed based on the results of the model.

This paper intended to present the MEM using outputs from advanced sonic processing to narrow down the uncertainty of geomechanics parameters that are exist in the model.

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