EARLY EOCENE CLIMATE OPTIMUM EVENT AT THE YPRESIAN AGE FROM SHALLOW MARINE DEPOSIT SALTRANGE EASTERN NEO-TETHYS, PAKISTAN

The early Eocene (Ypresian) Nammal formation exposed in Nammal Gorge in the Salt Range belongs to carbonate platform sedimentation of Tethys regime. The Eocene period marks the initial contact of the Indian plate with the Kohistan Island arc or the southern continental margin of Eurasia. This caused the development of widespread and stable shallow-water carbonate platforms; this shallow shelf platform favored the life of foraminiferas in the southern continental margin of the Neo-Tethyan ocean. Lithologically Nammal Formation is comprised of interbedded nodular limestone, marl, and shale.

This study dealed with the biostratigraphical analysis of the Nammal Formation in the Nammal Gorge, western Salt Range, Pakistan. The Nammal Formation is located at the Nammal Gorge section with about 76 m in the thickness, and it consists of predominantly shelfal limestone with interbedded shale, recessive limy siltstone, and marl. This research work identified several Genera’s of Foraminiferas, e.g., benthic and planktonic Foraminifera. Benthic foraminifera were observed in large quantities compared to planktons and nano-fossils, and it suggested that the Nammal Formation belongs to the lagoon to open marine environment. This work identified large benthic genera such as Assilina, Alvolina, Algae, Discocyclina Nummulites, Lockhartia, Operculina, and Echinoderm. These genera’s mark neomorphic sparry calcite cement that is often present as binding material between these foraminiferas or lime mud. The large benthic foraminifera marked early Eocene climate optimum globally from different sectors of Tethys.