Numerous unconventional resources have become economically viable with the development of horizontal drilling and multi-stage hydraulic fracturing. Unconventional reservoirs have variable degrees of heterogeneity and identification of good and poor reservoir properties is essential for efficient development to define the economic limits of a resource play. An integrated, multidisciplinary approach of correlating core facies to petrophysical wireline facies to seismic facies for tight unconventional sandstones is presented in this paper along with the results of a simultaneous, geostatistical seismic inversion. Seismic facies and reservoir rock properties, which are calibrated to wireline logs and core data, are mapped from 3D seismic inversion volumes. The maps provide a detailed understanding of the characteristics of the reservoirs, namely their spatial distribution, geometry, and internal architecture. This methodology demonstrates the tremendous value of incorporating stratigraphic, petrophysical, and geophysical data into a quantitative, integrated reservoir model.

A 1D Mechanical Earth Model (MEM) was built for the Albian section of a planned horizontal well in the south Campos Basin area in order to reduce risks for well placement, completion and stimulation in a fast track development program with reduced number of appraisal wells. Mechanical properties and stress profile along the wellbore for the design were determined from multiple data sources including core testing, advanced acoustic, wellbore image, processed petrophysics, micro-fracturing and in-situ formation pressure. These measurements enabled the definition of local correlations for the studied carbonate reservoir, estimation of geomechanical properties, and the creation of input for the completion design. The calibrated geomechanics model was used to evaluate the completion options for a horizontal well in carbonates to optimize reserves and maximize well productivity. Based on field characteristics and mechanical properties determined from this study, the horizontal well placement and drilling design was adjusted and an open hole completion with mechanical isolation was proposed to enable multiple fracturing in one continuous and efficient operation.

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