Logs and drillstem test pressure data indicate two stratigraphically separate carbonate reservoir intervals with separate pressure systems and potentially separate or stacked hydrocarbon pay at the Tricertops-2 well in Papua New Guinea, said InterOil Corp., Houston.
Drillstem test No. 8 in open hole at 4,111-4,859 ft flowed at 17.6 MMscfd of gas at 1,382 psig wellhead pressure on a 48/64-in. choke with 13.6-16.3 bbl/MMcf of condensate. InterOil said the gas flow rate compares favorably with results from equivalent DST intervals at Antelope-1 and Antelope-2, which were at rates of 12.4 to 18 MMscfd and 11.2 to 17.4 MMscfd, respectively.
The upper reservoir interval contains gas-condensate which preliminary pressure data from DST No. 7 indicate is on the same pressure trend as the gas and condensate tested 3.5 km away in the Bwata-1 well.
The deeper zone is separated from the upper reservoir interval by a 264-ft marl and argillaceous limestone interval at 4,869-5,133 ft, a potential intraformational seal.
DST No. 2 tested the intervalat 6,358.3-6,454.5 ft in this deeper section, and the data indicate a separate pressure system in this interval. An independent formation evaluation indicates potential movable liquid hydrocarbons in this lower reservoir interval, and DST No. 2 recovered small amount of condensate in the DST string. However, the presence of hydrocarbons in the other sections of this lower reservoir interval at this stage has not been confirmed by testing.
Phil Mulacek, InterOil chief executive officer, said, "We believe that the pressure data, flow rates recovered from the DSTs and well logs demonstrate a high quality porous reservoir. We are pleased to find that our aeromagnetic and gravity data utilized in combination with modern seismic data has yielded our second significant discovery of hydrocarbons in a reefal reservoir in Papua New Guinea.
“Our forward plan to obtain definitive test results from the lower reservoir section is to set casing over the entire reservoir interval and perforate zones of interest," Mulacek said.