PETROGRAPHIC AND FACIES EVALUATION OF MIDDLE SIWALIK SUBGROUP OF JAMMU, HIMALAYA

This paper embodies the results on the study of depositional environme nt, provenance and tectonic setting of Middle Siwalik Subgroup of Jamm u region. The data obtained on lithofacies, sedimentary structures and nature of contacts between various lithofacies, suggest multiple epis odes of avulsion and abandonment of the channel system for a new cours e in braided river system. Four variable plot of quartz types shows th at these sediments have been derived from low rank metamorphic source. The detrital modes (quartz, feldspar and lithic fragments) plotted on complementary ternary diagrams (QFL and Q(m)FL(t)) indicate that thes e sediments have been shed from recycled orogens, transitional are and transitional continental provinces.