Falkland Oil and Gas has discovered gas with its Loligo exploration well in the East Falkland basin, the company reported.

Well 42/07-01 has been drilled to a depth of 4,043 m (13,264 ft). It is clear from the initial well results that the main hydrocarbon phase within the T1 to T5 aged reservoir objectives is gas, a news release said, but it has not been possible to determine whether this gas has any liquid content.

Gas-bearing zones were encountered over a 1,300 m (4,265 ft) vertical interval from 2,420 m (7,940 ft) to 3,720 m (12,205 ft). Petrophysical analysis of the T1 to T3 intervals inclusive (2,420 m to 2,885 m, or 7,940 ft to 9,465 ft) indicates porosities ranging from 18% to 35% in the gas-bearing zones. Due to the thin-bedded nature of these sediments, it is difficult to assess precisely both hydrocarbon saturation and the total net hydrocarbon bearing reservoir, the news release said. Preliminary estimates, however, suggest hydrocarbon saturations ranging from 40% to 60% and net hydrocarbon bearing reservoir of between 10 m (33 ft) and 20 m (66 ft).

Within the T5 target two main hydrocarbon bearing zones were encountered (3,462 m to 3,558 m and 3,608 m to 3,705 m, or 11,358 ft to 11,673 ft and 11,837 ft to 12,156 ft). The net hydrocarbon bearing reservoir in these two zones was 46 m (151 ft) and 59 m (194 ft), respectively. Porosities ranged between 23% and 30%, averaging 24% and hydrocarbon saturations between 40% and 75%.

Attempts were made to obtain pressure data and collect fluid samples. This was unsuccessful, probably due to the fine grained nature of sediments in the gas bearing zone and also, not having access to the specialized test equipment appropriate for this type of formation, according to the release.

Determining the reservoir potential of the thin-bedded sandstones and siltstones using detailed petrophysical evaluation will be undertaken once the sidewall core samples have been analyzed back in the UK. These studies will facilitate a better assessment of resource potential and also help define the work that will be required to further appraise this discovery over what is a large complex.

FOGL is the operator of the well, holding a 75% interest. Its joint venture partner Edison International Spa holds the remaining 25% interest.

FOGL now intends to plug and abandon the well, which is expected to take approximately 10 days. FOGL and Edison believe that it would be premature to drill a second well on Loligo at the current approved location (Loligo northwest) before having undertaken detailed analysis of the current well results, the release said.