SEDIMENTARY FACIES ANALYSIS OF NAGRI FORMATION, KASHMIR BASIN, SUB-HIMALAYAS, PAKISTAN
Journal: Pakistan Journal of Geology (PJG)
Author:Noman Abbasi, Muhammad Sabir Khan, Muhammad Saleem Mughal, Muhammad Yasin
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Nagri Formation, the subject of this study, lies in northeastern part of Kashmir basin, Pakistan along a belt of about 250-kilometer square. The Nagri Formation forms alternate beds of sandstone, claystone and/or mudstone. These are molasse deposits formed during the Himalayan orogeny and are early Pliocene in age. The Formation consists of six sedimentary facies: para-conglomerate (N1) comprised of massive conglomerates with the absence of grading and matrix supported fabric of clayey sand; ortho-conglomerate (N2) are normal graded conglomerates and are poorly sorted having clasts supported fine to very coarse grain matrix; massive sandstone (N3) is composed of medium to coarse sized grains, contains massive sandstone beds and is poorly sorted with scattered pebbles at some locations; cross bedded sandstone (N4) consist of to medium to coarse textured, cross bedded sandstone; parallel laminated sandstone (N5) comprising fine to coarse grained and poorly sorted sandstone beds with thin parallel laminations; and mudstone (N6) comprised of massive claystone’s, siltstones and mudstone that lack any noticeable sedimentary structure. The conglomerates, sandstone and mudstone/siltstone/claystone facies are stacked in ascending order and are deduced as a sequence of channel bar and floodplain or over bank deposits confined to a braided fluvial system.