Ages and Depositional Environments of Paleogene Rocks in the Southern Maracaibo Basin, Venezuela: ABSTRACT

Abstract

Detailed studies of Paleogene rocks exposed in road cuts and rivers along the north flank of the Merida Andes in Venezuela provide a means of assisting the interpretation of subsurface data and therefore assessment of the hydrocarbon potential of the Southern Maracaibo Basin. Thick sections at Rio Chama, Rio Lora and Rio Lobaterita, together with many smaller outcrop localities, were measured and sampled to determine the ages and depositional environments of Paleogene formations. Observations and measurements taken at the outcrop include gamma ray signature, bed thickness, mineralogy, and associated sedimentary structures. Extensive sets of samples were taken for paleontological (especially palynology) analyses. This paper highlights the significant geological characteristics of the Barco, Los Cuervos, Mirador, and Carbonera formations, illustrated with measured sections showing gamma ray, geochemical, and palynological abundance logs. These observations together with proprietary subsurface data have made it possible to construct maps of Paleogene paleogeography of the Southern Maracaibo Basin, providing an understanding of the depositional environments and regional extent of potential hydrocarbon reservoirs and seals.