Method for determining movable closed porosity of low-clay-content shale reservoirs

Abstract

The application provides a method for determining movable closed porosity of shale reservoirs with low clay content, and relates to the technical field of shale exploration and development, and the method comprises the following steps: obtaining the actual temperature of the stratum corresponding to the shale sample to be measured; applying a stepwise temperature rise to the saturated shale sample, synchronously determining the connected porosity under each temperature gradient, and determining the temperature corresponding to the stable connected porosity as the highest safe drying temperature of the shale sample; determining the first connected porosity at the actual temperature; determining the second connected porosity at the highest safe drying temperature; and obtaining the movable closed porosity based on the first connected porosity and the second connected porosity. The application establishes a test and calculation method suitable for calculating the closed porosity proportion of shale with low clay content under different stratum temperature conditions, and further determining the degree to which the closed porosity can be converted into connected porosity, which is of great significance for shale oil and gas reservoir evaluation.

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