Oil and gas exploration and production company Petroceltic International has struck gas at the AT-4 well in the Illizi Basin of south eastern Algeria.

The AT-4 vertical well, the first of a four well appraisal campaign, encountered a gross gas column of 155m with no gas-water contact observed.

Additionally, static reservoir pressure readings indicated that the main Ordovician gas reservoir in this area is in the same pressure regime as that encountered at wells AT-1, AT-2 and AT-3.

The principal objective of the AT-4 well was to determine the nature and extent of the gas in place in this previously undrilled area of the field.

The well, which was drilled to a total depth of 2142m, has now been suspended, pending rigless fracture stimulation and flow testing over the coming month.

Petroceltic chief executive Brian O’Cathain said that the AT-4 well in the current Ain Tsila appraisal campaign has successfully achieved its objective of confirming the presence of a gas column with pressure continuity on the previously undrilled eastern flank of the field.

"Whilst AT-4 was designed with a primary focus on proving up gas in place rather than productivity, we are optimistic for a positive outcome from testing," O’Cathain said.