A granulometric screening framework for preliminary assessment of sand production susceptibility in unconsolidated sandstone reservoirs

Abstract Particle size distribution (PSD) provides rapid geometric information on unconsolidated sandstone materials, but PSD descriptors alone do not constitute a validated prediction of sanding onset. This study evaluates eight laboratory-derived sandstone PSD datasets using consistently recalculated characteristic diameters (D 10 , D 30 , D 50 , D 60 and D 90 ), the uniformity coefficient (Cu) and coefficient of gradation (Cc), and proposes a transparent granulometric classification for first-pass comparison. Cu ranges from 1.69 to 4.00 and recalculated Cc from 0.84 to 1.28. Using study-defined Cu boundaries, two samples are classified as narrowly graded (Cu < 2), five as moderately graded (2 ≤ Cu ≤ 3), and one as broadly graded (Cu > 3). The contribution is therefore not a deterministic sand-production model, but a structured workflow that converts conventional PSD descriptors into reproducible granulometric classes that can flag formations for progressively more detailed evaluation. The classes are interpreted as indicators of gradation breadth and possible differences in granular fabric and particle-mobility susceptibility; they have not been independently calibrated against critical drawdown, laboratory sand-production/retention tests, formation-strength measurements or field sanding observations. Consequently, the framework is intended for preliminary susceptibility screening only and should be integrated with geomechanical characterization, laboratory testing and production-condition assessment before completion decisions are made.