At Hakia-2, good gas shows have been encountered at several levels in the Irwin River coal measures but no shows were observed in the Dongara Sandstone, the partners said yesterday.

"The significance of the shows will be determined once the well reaches the revised total depth of 3,006m measured depth and wireline logging is completed," Origin said in a statement.

Yesterday morning, Hakia-2 was drilling ahead in 216mm hole at 2,912 metres at 6am and progress for the week was 660 metres.

Meanwhile, the partners said the gas exploration Tarantula-1 sidetrack-1 (Tarantula 1ST1), in onshore Perth Basin production licence L11, was running in a hole to drill ahead at 6am yesterday.

Since last week, the well has been kicked off from the original Tarantula-1 well bore and drilled from 1,295m to 2,137m.

Tarantula 1ST1 is about 6.5 kilometres north of the Beharra Springs gas processing plant and will evaluate the potential of the Wagina Formation equivalent to the producing horizon at the nearby Beharra Springs and Beharra Springs North gas fields, the companies said.

The well will be deviated to a target bottom hole location about 90m south of the Tarantula-1 bottom hole location, with a planned 3,320m total depth.

The top of the objective Wagina Formation is expected at 3,219m, the partners said.

Participants in L1 and L2 (excluding the Dongara, Mondarra and Yardarino fields) and Hakia-2: Arc Energy (operator) 50% and wholly-owned subsidiary Origin Energy Developments 50%.

Participants in L11 are Origin Energy Developments (operator) 67% and Arc Energy 33%.