The Paleocene of La Concepcion Field (Maracaibo Basin, Venezuela): Transition from Andean to Caribbean active margin

The Paleocene Guasare Formation of La Concepcion Field (Maracaibo Basin, Venezuela) consists of thin carbonates that were deposited in a dynamic near-shore marine setting greatly influenced by terrestrial siliclastics and muds. In seismic data, the Guasare Fm. shows uniform thickness and subparallel reflectors. Facies trends were not evident from the 3D seismic data set. Amplitude maps revealed one structurally-related anomaly. The regional setting of the Paleocene was clarified showing that Late Cretaceous foresets indicated a source from the Andean active margin to the west. These clinoforms were overlain by the Paleocene Guasare Formation and its western partial equivalent, the Marcelina Fm., a siliciclastic and coal sequence. Only the overlying Eocene Misoa Formation indicates a northeasterly clastic input and eastward thickening associated with the emplacement of the Lara nappes of the Caribbean active margin. This study is based on 3D seismic data, some well logs, and well cuttings. Cores were unavailable