Origin of Miliolite Rocks of Kutch-Microfaunal Evidences

Miliolites occur within the Kutch highlands as thin horizontal sheets occupying topographic depressions or as obstacle dunes resting against the slopes of big hills. Sheet deposits of the low-lying ground, reveal a marine origin and are seen to consist of pellets and microfossils embedded in a micritic to fine sparry matrix. These valley-fill sheet deposits are characterised by a faunal assemblage typical of warm, clear, shallow, carbonate-rich sea, where terrigenous influx was poor. On the other hand, the obstacle dunes typically comprise aeolinites and appear to have developed during the regression of the sea, the strong winds having lifted the exposed carbonate sands and dumped them against the nearby hillsides. The higher strand line indicated by these marine miliolites could be related to one of the Quaternary transgressions.