Floristic zones in the Mesozoic formations and their relative age

Abstract

Through a comprehensive analytical study of the Mesozoic flora and synthesis of the available data 12 assemblage zones and a floral succession are established. These assemblage zones also extend into the Early Cretaceous flora in the neighboring countries: Pakistan, Nepal, Bhutan and Sri Lanka. The Gondwana Triassic elements and the European Jurassic-Cretaceous elements in the flora are highlighted. The inter-relationship of the Mesozoic floras of Gondwanaland, European and Asian countries is examined. The relative age of the biozones is worked out on the basis of plant megafossils, palynology, paleontology, stratigraphy and radiometry. It is suggested that the concept of Gondwana be replaced by chronostratigraphic terms, viz., Triassic, Jurassic and Cretaceous for the Indian Mesozoic sediments.