Sedimentary Geology of Mixed Siliciclastic-Carbonate Succession, Early Cambrian Jutana Formation, Salt Range, Pakistan

The Early Cambrian Jutana Formation is a dolomitized succession of shallow water to subtidal lithologies in the Salt Range, Pakistan. Two stratigraphic sections were studied to interpret the facies, depositional environment and sequence stratigraphy of the Jutana Formation. Based on lithology, sedimentary structures and geometry, five main sedimentary facies were recognized in the Jutana Formation which include; sandy dolomite alternating with siltstone facies, dolomite facies, dolomitic siltstone and mudstone facies, sandy dolomite facies and thick-bedded dolomite facies. The presence of mudrocks and parallel lamination indicates shallow water lagoonal facies, while wavy bedding, herringbone cross bedding and ripples cross lamination show tidal flat facies. The sedimentological and petrographic analysis reveals that the Jutana Formation was deposited under shallow warm water, well-oxygenated and calm conditions of restricted marine environments. The sedimentary facies represents siliciclastic-carbonate mixed tidal flat environment of deposition.

Keywords:

Early Cambrian , Jutana Formation , Salt Range , Sedimentology , Tidal flat