ExxonMobil Corp. have announced that the Liza-2 well has encountered approximately 190 ft (58 m) of oil-bearing sandstone reservoirs in Upper Cretaceous formations. It has confirmed the presence of high-quality oil offshore Guyana from the same high-porosity sandstone reservoirs seen in the Liza-1 well which was completed in 2015 and encountered more than 295 ft (90 m) of oil-bearing sandstone reservoirs. This is a significant oil discovery with potential recoverable reserves of 800 to 1,400 MMBOE (ExxonMobil press release 30th June 2016) in the Stabroek Block located off the coast of Guyana.
The Guyana Basin is a largely unexplored petroleum province which has seen little exploration activity since the late 1980s. A detailed prospectivity evaluation based on Spectrum’s 4,600 km of Multi-Client 2D seismic data has identified multiple play types including large early Cretaceous structures, amplitude-supported structures with over 200 km2 of closure, stratigraphic on-laps, ponded turbidites, basin floor fans and Tertiary mass transport complexes.
In the region of Exxon’s exploration drilling, the Cenomanian-Turonian Canje formation source rock is overlain by a thick Cretaceous section deposited within a major submarine canyon. Various structural, stratigraphic and combined structural-stratigraphic hydrocarbon traps are observed on nearby 2D seismic lines, many of which are associated with high amplitude anomalies. The 2016 drilling campaign targeting the Skipjack and Payara prospects, with a known petroleum system in place should continue to prove the large hydrocarbon potential offshore Guyana, estimated by the USGS to be at least 15 BBO and 41 TCFG . This would suggest the Guyana Basin as one of the most attractive under-explored basin in the world.
Below is a Spectrum PreSTM seismic line through the Liza discovery showing an amplitude-supported structure which can be mapped using Spectrum’s 2D seismic data. Similar amplitude-supported structures are identified on Spectrum’s 2D data covering the Skipjack and Payara prospects.