Hertig, Stephen P.¹
(1) EOG Resources, Inc, Houston, TX

ABSTRACT: Charge Analyses of Oil and Gas Fields within the SECC Block, Columbus Basin, Trinidad and Tobago

Source rocks adjacent to and underlying the SECC block are inferred to have charged discovered, on-block traps containing as much as 1.5 TCF of gas/condensate and minor quantities of oil. Critical components to understanding hydrocarbon charge in the block are 1) source rock distribution, 2) source rock maturation and 3) hydrocarbon migration paths. Source rocks of the Cretaceous age Naparima Hill formations that crop out onshore Trinidad are inferred to extend eastward beneath the SECC block. A seismic horizon, interpreted to represent these source rocks, ranges in calculated depth from about -5000m to -6000m across the block. Maturation analyses suggest these potential source rocks past quickly through the oil window after about 5 Ma and became gas prone as the Columbus basin quickly deepened from the rapid sedimentation of Pliocene to Recent age Orinoco River sediments. Hydrocarbon migration path creation, source-to-trap geometries and utilization timing were all determined by post-Miocene tectonics of the Columbus basin.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.