Abstract

Calcareous nannoplankton, a group of microfossils that evolved rapidly during the late Mesozoic and the Cenozoic eras, is a new and very reliable biostratigraphical tool. Its usefulness has been tested successfully during the drilling of the JOIDES* Deep Sea Drilling Project and by some of the oil companies operating in the Gulf Coast Area, USA.

Standard Calcareous Nannoplankton - Zonations for the Paleogene and for the Neogene are now available. These zonations have been proposed by Martini (1970) and Martini & Worsley (1970), respectively.

The study of calcareous nannoplankton in Indonesia as a new biostratigrahic tool has only been started recently, however, some very encouraging results have been obtained in Central Sumatra. If similar results can be obtained from other parts of the country, the prospect of this study in Indonesia will certainly be very bright. The role of the oil industry in developing this field of study is very important, since the oil companies have direct access to the basic data.

It is believed that establishing a standard zonation for Indonesia is not impossible. Once this is established, it will be beneficial to both the oil industry and the academic institutions, and more important it will be a major contribution to the study on the stratigraphy of Indonesia.