Copyright by Nysha Chaderton 2009 - The University of Texas at ...

Ridge high. The traps would be associated with the large thrust faults that create the
ridges and mini basins of the Zone of Piggy Back Basins (Figures 4.3 and 4.10).
The implications of the interpretation of the Scotland Formation as a forearc basin
are that depositional lobes should be elongated parallel to the major structural highs at the
time of deposition. Therefore, it is speculated herein that coarse-grained clastic deep
water deposits, similar to those seen in outcrop and in seismic to the south, may exist to
along the trend (to the north and south) of the Barbados Ridge and to the west within the
Tobago Basin proper. If this is correct, the likelihood of finding deposits similar to or
time equivalent to the Scotland formation decreases eastward. It is important to note that
within the piggyback basins of the BAP, the Miocene age and younger, sand and shale
successions have similar architecture and geometries.
Hydrocarbon exploration of the BAP region must therefore take into account two
distinctive play types:
1. The raised forearc basin reservoir plays that are located along the high
of the Barbados Ridge and the eastern margin of the present day TFB.
2. The younger piggyback basin reservoir plays that have been deposited
within these mini-basins that have formed on the BAP.
The complex structuring of a convergent margin setting creates folds and faults
that may give rise to hydrocarbon traps. However active faults may provide permeable
pathways that cause leakage (Dolan, et al., 2004). Stratigraphic heterogeneity is complex
as the potential reservoirs are highly channelized (Chapter Two, this volume).
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