THE MAJOR ELEMENTAL COMPOSITION OF MIDDLE PALEOCENE SEDIMENTS OF SOUTHERN INDUS BASIN PAKISTAN: IMPLICATION ON PROVENANCE

Abstract

The current study area is a northeastern part of Karachi arc and located in Lakhi Range and also the Southeastern part of Karachi arc which is Thar Desert. Present study is focused on Bara Formation with specifically source rock study, as it could be understand that from where these detritus were being supplied, either from Indian craton or Asian plate in Middle Paleocene time. These sediments are composed of Sandstone, Shale, Coal, and Siltstone with some traces of fossils. Ninety five samples of Middle Paleocene sediments from three localities (Ranikot, Lakhra and Thar) with five stratigraphic sections have investigated for geochemical elements identification. The studied sediments have been classified as Litharenite, Sublitharenite, arkose, Sub-arkose greywacke, Iron sand, Iron shale. PIA and CIA of studied section of basin had been facing low/low to high weathering conditions in source area. The majority of samples indicate the passive margin tectonic settings. Middle Paleocene sediments of Southern Indus Basin is concluded here as the sediments had been supplied from Indian shield rocks and it can be summarized that the Indian plate was not collided with Asia plate in Middle Paleocene time (61.6-59.2 million years age) at Southern Indus Basin of Pakistan.