ABSTRACT

Preliminary investigations of the stratigraphic utility of calcareous nannofossils in the Gulf of Mexico-Caribbean region were begun prior to 1954. Most of the applications of these minute forms, however, have been published during the last decade. Their stratigraphic occurrences have been documented for the Late Cretaceous and younger sections of the region, but, insofar as is indicated through publication, they have not gained the status of routine application in onshore and nearshore subsurface studies.

The stratigraphic value of calcareous nannofossils has, however, been amply demonstrated. They proved very useful for the rapid evaluations needed routinely in the shipboard work connected with geological oceanographic studies. Their worldwide applications, particularly in the Joint Oceanographic Institutes Deep Sea Drilling Program (DSDP), include the Caribbean and Gulf of Mexico. Late Cretaceous through Holocene species occurrences have been calibrated for the Gulf region with the planktonic foraminiferal-based zonation scheme, on Leg X of the D.S.D.P.

Current work in or applicable to the Gulf of Mexico-Caribbean region, is summarized in the ten papers given in the concurrent Symposium on Calcareous Nannofossils. The proceedings of this symposium are not included in the G.C.A.G.S.-S.E.P.M. Transactions but are published in a separate volume sponsored by the Gulf Coast Section of the S.E.P.M.