Geochemical attributes of Pliocene Dhok Pathan Formation, Eastern Sulaiman Fold and Thrust Belt, Pakistan: implications for provenance, paleoenvironmental, and tectonic settings.

Autor: Zaidi, Syed Irfan Ali, Ahsan, Naveed, Rehman, Saif Ur
Zdroj: Arabian Journal of Geosciences; Nov2021, Vol. 14 Issue 21, p1-30, 30p
Abstrakt: The Late Miocene-Pliocene Dhok Pathan Formation (DPF) fluvial sequence of Eastern Sulaiman Foldbelt and Thrust Belt (SFTB) has different lithofacies of sandstone and mudstone deposited in the Himalayan foredeep basin. The present study deals with detailed geochemical analyses of DPF to deduce its provenance, weathering, and tectonic settings. The geochemical data of major oxides plot on scatter diagram shows that the sandstones of DPF are predominantly Arkose-Subarkose and Litharenite-Sublitharenite which were mainly sourced from granitic composition and deposited in fluvial conditions under semi-arid to arid climate. The low elemental ratios of Ni/Co and Cu/Zn indicate oxic conditions during deposition. The mudstone's ICV values are 1.44 indicating that the source area was influenced by moderate to high weathering. The geochemical analysis indicates lower values of Zr, Nb, Y, and Y/Ni ratio in studied area which point out the existence of ultramafic/mafic sequence in source area. The tectonic discrimination diagrams depict active continental margin tectonic settings for provenance of DPF with partial influx from Continental and Oceanic Island Arc. The present study concludes that clastic rocks of DPF were mainly sourced from Himalayan orogeny with partial influx of Kohistan-Ladakh arc and subsequent deposition in Himalayan foredeep basin which coincides with regional tectonic scenario. Interpretation of paleoenvironments and basin tectonics by geochemical analysis will help to delineate the poorly understood uplift and denudation history in SFTB. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index