Search for Provenance of Oligocene Barail Sandstones in and around Jotsoma, Kohima, Nagaland

Abstract: Provenance of the Oligocene Barail sandstones has been ascertained by means of petrographic and heavy mineral studies. Petrography reveals an abundance of angular to sub-rounded monocrystalline, non-undulatory quartz followed by lithic fragments. The overall composition of sandstones matches with those of sublith-arenites. The heavy mineral suite of Barail sandstones displays rounded to sub-rounded as well as euhedral / angular grains of iron oxide, zircon, tourmaline, rutile, kyanite, sillimanite and staurolite in decreasing order of abundance. Petrography coupled with heavy mineral suite suggests for a mixed provenance dominated by a sedimentary source of recycled orogenic provenance in a foreland basin setup.