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Detrital mineralogy of the sandstone of Fort Member of Jurassic Jaisalmer basin has been investigated with respect to provenance, the influence of palaeoclimate, distance of transport and effects of diagenesis on the detrital mineralogy. Petrographic studies based on quantitative analysis of the detrital minerals revealed that the sandstones are composed mostly of quartz, feldspar, mica, chert, rock fragments and heavy minerals. The detrital modes of the studied Fort Member sandstone, which are indicative of mature stable cratonic blocks and recycled orogen provenance, where sediments are likely to be derived from collision orogen under semi-humid to humid climatic conditions. Petrographic data coupled with the palaeocurrent analysis results indicate a mixed provenance including granites, granite-gneisses, low and high-grade metamorphic rocks of the Aravalli craton.

Two major facies associations are identified in the Upper Kaimur Group of the Son Valley, namely, tidally influenced fluvial channel facies association and tidal sand flat association. Lithofacies supports the Dhandraul Sandstone as the product of a tidally‐influenced fluvial channel and the underlying Scarp Sandstone as a tidal sand flat, which endorse a tide‐dominated estuarine setting. Grain size analysis shows that most of the sandstone samples are medium‐ to coarse‐grained and only small fractions are of fine‐ and very fine‐grained categories. In general, sediments are moderately well sorted, near‐symmetrical to fine‐skewed and leptokurtic to mesokurtic in nature, suggesting deposition under fluctuating energy conditions in different geomorphic domains from a tidally‐influenced fluvial channel to beach settings. Bivariant plots combining the textural parameters imply that marine processes dominate over fluvial processes in the Upper Kaimur Group sediments. Cumulative curves and C–M plot suggest sediment transport mainly by saltation and bottom suspension processes under varying energy conditions.

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