AAPG Annual Convention and Exhibition

Datapages, Inc.Print this page

La Vela Bay, Offshore Falcon Basin, Western Venezuela: Eastern Extension to the La Perla Carbonate Reservoir Trend

Abstract

Discovery of the 16 TCF La Perla gas giant in 2009 was the first major carbonate-hosted giant reservoir discovered in northern South America. Moreover, the La Perla discovery was found in the northern part of the Gulf of Venezuela on the exotic Caribbean plate and did not involve the more familiar hydrocarbon habitat in Venezuela of foreland basin clastic reservoirs sourced by the Cretaceous passive margin. We describe the La Vela carbonate reservoir, offshore Falcon basin, western Venezuela, located 170 km southwest of La Perla and consisting of an Early Miocene reefal reservoir directly overlying igneous-metamorphic basement with associated Miocene age source rocks. The reservoir produces both light-medium oil and gas and more than half of the reservoir presents effective porosities between 8 and 15%, and permeabilities less than 15 mD. We used 960 km2 of 3D seismic data tied to 40 wells to map the reef reservoir facies over an area of 11000 km2. The thickness of the limestone varies from several meters to 150 m. Well data show that the facies is a shallow carbonate ramp with localized reef buildups. We use the curvature and other attributes for the seismic volume to show that variations in porosity are controlled by diagenetic effects rather than by fracturing. The level of deformation is much less than in the neighboring areas of the onland, inverted Falcon basin to the south. We have identified good seals at local and regional scales that correspond to maximum flooding shale units. We use paleogeographic maps to show a possible Miocene reefal carbonate trend running along the southern edge of the exotic Caribbean plate and linking the La Vela area to the La Perla area of the Gulf of Venezuela.