Revised stratigraphy of the lower Cenozoic succession of the Greater Indus Basin in Pakistan

Abstract

Abstract. A refined stratigraphy for the lower Cenozoic succession of the Greater Indus Basin in Pakistan is presented. This region preserves an important East Tethyan marine succession through the Paleocene–Eocene, but its interpretation in terms of regional (tectonic) and global (climatic) effects has been inhibited by poor stratigraphy. Established dinoflagellate, nannofossil, planktonic foraminiferal and shallow benthonic foraminiferal biostratigraphical data for the Greater Indus Basin in Pakistan are collated, reinterpreted (where necessary) and correlated with the global standard chronostratigraphy and biostratigraphy of the early Palaeogene. Inter-regional stratigraphical correlations for the Upper Indus Basin and Lower Indus Basin are resolved. Age-diagnostic larger benthonic foraminifera from the Late Paleocene Lockhart Formation are illustrated. These collective biostratigraphical data provide a means of interpreting the lithostratigraphy and physical stratigraphical relationships of the Palaeogene succession in terms of the interplay between local tectonics (India–Asia collision) and global sea-level change. The timing of the Tethys closure, initial and final contact of the Indian–Asian plates, and dispersal of land mammals on the Indian Plate are discussed and correlated in the stratigraphical record of the basin.