APTIAN TO MAASTRICHTIAN PALEOBATHYMETRIC RECONSTRUCTION OF THE EASTERN VENEZUELAN BASIN

The objective of this study is a paleobathymetric reconstruction of th e depositional environment during the Cretaceous (Aptian-Maastrichtian ) on the northern flank of the Eastern Venezuelan Basin. The model is based on the presence of benthic foraminifera in 17 well sections, spr ead across the paleoslope in a passive margin. Cluster analysis separa tes five distinct assemblages of foraminifers. The analysis is based o n the assumption that the species must occur in 10% or in at least two wells of the area. The R-mode for each well provides clusters of spec ies that are similar in distribution and abundance trends. These clust ers together with the diversity and abundance of planktic foraminifers , dinoflagellates, pollen, spores, calcareous nannofossils, and sedime ntological data help to delineate the biofacies. The biofacies are dis tributed in a pattern from the updip position (southwest) to the downd ip position (northeast). The shallowest biofacies (0-50 m) is represen ted by Ammobaculites sp., Haplophragmoides sp., Lituolidae, with abund ant terrestrial palynomorphs and dinoflagellates. Abundant species in depths greater than 100 m are Praebulimina carseyae, Epistomina lacuno sa, Gavelinella sp., Buliminella sp., and Pullenia cretacea. This biof acies interpretation allows us to establish a paleocoast orientation d uring the Aplian-Maastrichtian. The establishment of the age-paleobath ymetry relationships in this area provides the basis for the stratigra phic reconstruction of the Cretaceous in the Eastern Venezuelan Basin, thus reducing the risk for oil exploration.