Título: Geochemical Modelling of the Principal Source Rocks of the Barinas and Maracaibo Basins, Western Venezuela

Autor: Tocco, R.; Francois, P.; Gallango, O.; Alberdi, M.; Passalacqua, H.

Fuente: Boletín Sociendad Venezolana de Geológos, 22 (2): 17-28, 1997

Año: 1997

Descriptores: Venezuela; Lake Maracaibo; Barinas; La Luna Formation; Ocrocué Group; Geochemical Modelling; Carbonera Formation.

Tipo de documento: Articulo

Resumen:

This study presents a gechemical review of the principal source rocks in the western Venezuela basins. The area covers more than 100.000 Km2, and includes the Lake Maracaibo and the Barinas-Apure basins. The geochemical modelling regconizes three source rocks: 1) the main one, corresponding to the K3-K4-K5 Cretaceous sequences and represented by La Luna, Capacho and Navay Formations, 2) a secondary one, corresponding to the T4 Oligocene sequence, represented by the Carbonera Formation, and 3) and accessory source rock, K7-K8 Paleocene sequences, represented by the carbonaceous shales and coals of the Orucué Group and Marcelina Formation. Three periods hydrocarbon expulsion were defined for La Luna Formation (Early Eocece-Middle Eocene, Late Eocene-Early Miocene and Early Miocene-Holocene), and one principal period of hydrocarbon expulsion for the Orocué Group and the Carbonera Formation (Plio-Pleistocecene and Middle Miocene-Plio-Pleistocene).