GSSP of the Meghalayan Stage in the Mawmluh Cave

The Mawmluh Cave is formed along the contact between Early Eocene Lakadong dolomite of Sylhet Limestone Formation and the Therria Sandstone Formation (Gogoi et al., 2009). At present, the cave is 7.2 Km long maze with many openings and decorated with stalactites, stalagmites, columns, drapes and moon milk.

The Meghalayan Stage is the newest entrant in the geologic history of the Earth and; latest of three subdivisions of the Holocene Epoch. The International Commission on Stratigraphy officially ratified it along with the earlier Greenlandian and Northgrippian Stages (Walker et al., 2018). The lower boundary of the Meghalayan Stage is defined at a specific level in a stalagmite of Mawmluh Cave. The uranium series dated Upper Pleistocene to Upper Holocene stable isotope profile shows a marked shift to heavier isotopic values at ~4.2 ka, reflecting an abrupt reduction in precipitation due to a weakening of the monsoon across the Indian sub-continent and southeast Asia (Berkelhammer et al 2012). Due to abrupt mega-drought, the agriculture-based society were nearly collapsed. The 4.2 ka event was global or near global in nature and constitutes a timestratigraphic marker (Walker et al., 2018).