Abstract: Cretaceous Cogollo Group Study--District Zulia Occidental
R. Lagazzi, G. D'Antonio, O. Hung, A. Avila
The Cretaceous Cogollo Group, with over 1500 feet of platform carbonate and shale section, contains important oil accumulations in the west portion of the Maracaibo basin. However, after discovery of the major oil fields, all subsequent exploration and exploitation efforts led to disappointing results.
This paper summarizes the study of the Cogollo Group in the Lake Maracaibo West Coast area, where light Cretaceous oil may have an impact on the total reserves. After integrating the Cogollo Group into the regional framework, the study focuses on the District Zulia Occidental, where over 40 deep wells either penetrated or tested the reservoir.
Structural and stratigraphic descriptions are enriched by a significant amount of core and petrophysical data that leads to a better understanding of the reservoir layering and pore geometry. Well production performance and reservoir data are incorporated to the study as additional tools to determine the size of the oil accumulations.
Finally, the study addresses the possibility of drilling slant or horizontal wells as a way to reduce the number of dry holes or marginal producers.
AAPG Search and Discovery Article #90951©1996 AAPG International Conference and Exhibition, Caracas, Venezuela