Fossil dinoflagellates: an emerging tool in Indian biostratigraphy

Abstract

The total span of fossil dinoflagellate research in India stretches within the last three decades. Two distinct phases of this study are recognised, the phase of Reconnaissance and Understanding (1961-70) and the phase of Establishment and Refinement (1971-1990). The significance of dinoflagellate cysts in resolving various biostratigraphic problems of Mesozoic and Cenozoic sedimentary sequences is discussed citing specific examples from Indian basins. Recent approaches towards achieving biostratigraphic precision through integration with smaller planktonic and larger benthonic foraminifera, ammonites, and calcareous nannoplankton, are specifically highlighted focusing the potential of dinoflagellate cysts to resolve the time boundaries. A review of the previous literature has revealed that wrong identifications, especially of marker taxa, have led to major errors in age determination of sedimentary sequences. A few cases are exemplified. An appeal has been made to fellow palynologists to be careful in presenting geological and palynological data to maintain the viability and potential of this group of microfossils in biostratigraphy.