Characterisation of the mechanical and petrophysical properties of quarried sandstones was conducted to assess their suitability as reservoir rocks. Five sets of outcrop sandstones, covering a range of porosity and permeability were identified as potential geomechanical analogues for North Sea sandstones. A comprehensive series of mechanical and petrophysical tests were undertaken in order to evaluate the mechanical properties of the sandstones (modulus of elasticity, Poisson's ratio and compressive strength) over a range of confining pressure likely to be encountered in the North Sea and basic petrophysical characteristics defined by grain density, porosity and permeability. The quarried sandstones have been found to be suitable reservoir analogues. The post failure sand production potential of the sandstones was examined by investigating the failure modes and analysing the granulometric characteristics of the comminution debris created by post peak strength sliding along shear surfaces.

Data generated from the laboratory testing were used as input parameters to investigate the propensity of sand debris production and formation stability in a hypothetical wellbore using the yield energy model. This model quantifies the energy available for rock fragmentation and describes the extent of the yield zone as a function of production rates and drawdown pressures. The geomechanical appraisal, which is a necessary component of the approach, also serves as a source of representative mechanical properties data available as input for reservoir simulators and other rock mechanics related analysis. The model was found to be applicable for a wide range of sandstones.

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