Reservoir
Characterization and Hydrocarbon Implications of the Early
Pliocene Deltaic Sedimentary Succession of the Columbus Channel, Trinidad
Rene R. Winter and Ronald J. Steel
University
of Texas at Austin, Austin, TX
The PlioceneāPleistocene (PP) succession of the Columbus Basin, eastern
offshore Trinidad is a prolific hydrocarbon province. A new stratigraphic
framework correlating basinwide stacked, 4th/5th-order sequences of the PP shelf
succession records the regional cyclic shelf transits of the PP Orinoco. This
new framework has the potential to drive
new play concepts and an improved
understanding of the
reservoir
architecture that can sustain reserve growth as
the current
reservoir
developments mature. Recent integration of well, outcrop
and seismic data between the onshore Trinidad Southern Basin and offshore
Columbus Channel is allowing reconstruction of the evolution of the Early
Pliocene shelf margins as they accreted eastwards. The earliest Pliocene
paleo-Orinoco shelf margin in the study area shows spectacular shelf-edge
collapse, canyon development, and bypass of sediments into the deepwater basin.
Data shows these processes to coincide with progradation and shoreline
regression, followed by a time of significant transgression and westward
backstepping of the delta. A second phase of early Pliocene regression brought
the delta back to the shelf edge and initiated a new period of vigorous
shelf-margin growth. This phase of shelf-margin growth was accompanied by
significant growth-fault development, but apparently little canyon generation.
Integrated seismic, well and outcrop data along the southern regions of Trinidad
onshore and offshore will enable a more detailed understanding of the role that
the paleo-Orinco played in Orinoco Shelf Margin development.
AAPG Search and Discovery Article #90039Ā©2005 AAPG Calgary, Alberta, June 16-19, 2005