A rock physics modeling and 2D seismic inversion study indicate that the Lower Cretaceous Drombeg stratigraphic prospect in the South Porcupine basin offshore Ireland may be a hydrocarbon-bearing sandstone, said Providence Resources PLC.
Providence said Drombeg demonstrates a significant seismic amplitude anomaly and low seismic impedance as well as a marked AVO response. The inversion study concluded that the mapped seismic anomaly is consistent with a modeled hydrocarbon-bearing sandstone interval that has a seismically derived thickness of 200-300 ft.
Providence’s mapping shows that the anomaly covers 240 sq km and is interpreted to be the deepwater equivalent of Lower Cretaceous Apto-Albian aged shallow-water marine sandstones encountered in the BP-operated 43/13-1 well, drilled in 1988. That well, 80 km from Drombeg, encountered 70 ft of net Apto-Albian sandstone with average porosity of 19%.
An underlying second seismic anomaly has also been identified and modeled to be consistent with hydrocarbon-bearing sandstone with a seismically derived thickness of 140-200 ft, and both anomalies appear to have a potential common downdip depth termination.
A major Jurassic tilted fault block closure covering 150 sq km has been mapped beneath the prospect, and a marked fluid escape feature has been identified at its crest. This ‘chimney’ appears to terminate at the downdip edge of the Drombeg seismic anomaly and provides potential evidence of hydrocarbon sourcing and migration into the prospect, Providence Resources said.
Drombeg is in Licensing Option 11/9 in which Providence is operator with 80% interest and Sosina Exploration has 20%. It is 3,000 m below the seabed in 2,500 m of water 220 km off West Cork and 60 km from the Dunquin prospect that ExxonMobil has committed to drill in the second quarter of 2013.
Providence Resources said it might not seek a partner with deepwater operating experience if results from the Dunquin well turn out positive.