Sedimentology and Biostratigraphy of the Chorgali Formation, Potwar and Hazara Sub-Basins, Upper Indus Basin of Pakistan: Implications for the Closing Stage of the Eastern Neo-Tethys Ocean

• Main Author: Khan, Muhammad Tufail
• Other Authors: Salad Hersi, Osman, Qing, Hairuo, Tariq, Mohammad
• Format: Thesis
• Language: English
• Published: Faculty of Graduate Studies and Research, University of Regina 2022
• Subjects: Planktonic foraminifera
• Online Access: http://hdl.handle.net/10294/15560; https://ourspace.uregina.ca/bitstream/handle/10294/15560/Khan_Muhammad_Tufail_MSc_Geol_Fall2022.pdf

A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Geology, University of Regina. ix, 120 p. The Chorgali Formation is a hydrocarbon-producing lithostratigraphic unit that occurs in different sub-basins of the Indus Basin in northern Pakistan, such as Potwar and Hazara sub- basins. The formation is part of a very thick carbonate succession deposited in the eastern Neo- Tethys Ocean shelf. It conformably overlies on early Eocene Sakesar Formation in southern Potwar sub-basin and lies on Margala Hill Limestone in the northern Potwar sub-basin and Hazara sub-basin. The Chorgali Formation is either covered by Miocene continental deposits of Murree Formation (Himalayan molasse deposits) or middle Eocene mixed clastic-carbonate succession of marine to continental beds of the Kuldana Formation. This study addresses the Chorgali Formation of the Potwar and Hazara sub-basins. This study intends to explore the spatial and temporal evolution of the Chorgali Formation as preserved in the Hazara and Potwar sub-basins and analyze it within the regional tectono-eustatic context. Six sections in the Potwar sub-basin and two sections in the Hazara sub-basin were studied; they give an average thickness of 32.5 m for the formation. Field observations and petrographic analyses of the studied sections allowed the recognition of nine lithofacies units (LF1-LF9) for the Chorgali Formation. These lithofacies include Calcareous Sandstone (LF1), Intraclastic Dolomitic Packstone (LF2), Algal-miliolid Mudstone (LF3), Coralline Algae Mudstone (LF4), Assilina-Nummulites Floatstone (LF5), Mixed Benthic-Planktonic Foraminifera Wackestone (LF6), Benthic Foraminifera Rudstone (LF7), Shale Lithofacies (LF8), and Planktonic Mudstone (LF9). The sedimentary features and fossil associations of the formation suggest that deposition of the formation took place in a homoclinal carbonate ramp characterized by low to moderate energy hydrodynamic conditions. ...