E. Lehner's "Introduction to the Geology of Trinidad" prompted this paper which summarizes the geology and oil possibilities as given by Lehner, and the writer's more recent information which modifies and amplifies that of Lehner.

The discovery of commercial accumulations of oil in eastern Venezuela led to the stratigraphical correlation between Venezuela and Trinidad. Trinidad will always be foremost in the geological literature of the Antilles and northern South America because of its many type localities established by original description of their well preserved Tertiary fossils. Because of the complexity of stratigraphical correlation, geologists should agree to a standard terminology for recognized formations--extraordinarily rapid lateral changes in most beds have been responsible for the abundance of non-indicative nomenclature.

Trinidad is a part of the Caribbean Coastal Range of Venezuela and displays all the structural characteristics of this mountain system.

The discovery of new oil fields in Trinidad is highly probable, but owing to complicated geological conditions information obtained from intensive wildcat drilling should supplement that from geologic mapping. Indications of oil in the Cretaceous of Trinidad are almost as common as those in beds of the same age north of the Guanoco area of eastern Venezuela. With the exception of insignificant production in the Lizard Springs field, no oil has been found in the Cretaceous of Trinidad. No beds older than the Cretaceous have been found in Trinidad.