Operator AWE (50%) and Origin Energy (50%) said the well intersected a 95m gross gas column, however wireline logs and pressure data have identified substantial upside potential.

The well was drilled to a revised total depth of 3507m having drilled through the full prospective section and into the Holmwood Shale.

The primary and secondary targets were penetrated at depths close to prognosis with good gas shows being encountered in the Kingia, High Cliff and Dongara sandstones.

Gas shows were also observed in the Irwin River Coal Measures and the Carynginia Shale, two unconventional targets that are considered long-term development options.

AWE said the gas-water contact at Waitsia was established at 3432m, about 350m below the top of the mapped structure.

The data so far shows that the Kingia and High Cliff sandstones are likely to be continuous with equivalent zones in the Senecio-3 well.

Overall reservoir quality appears to be better than Senecio-3 with considerable thickening of the High Cliff Sandstone pay interval.

Conventional net gas pay for the well is interpreted to be 18m with average porosity of 18%.

Preliminary compositional analysis indicates carbon dioxide levels of less than 4%, which is consistent with Senecio-3.

A tight gas reservoir, equivalent in quality to Senecio-3, was also encountered in the shallower Dongara

Sandstone and further confirms the extent of the Senecio field.

The data acquired so far support the gross 2C contingent resource estimate of 290 billion cubic feet of gas for the Waitsia field, and the thickening of the net conventional gas pay in Waitsia-1 indicates considerable potential upside.

The gas-bearing intervals appear to be in pressure communication across the northern culmination from Senecio-3, indicating that this region of the field has sufficient resources for commercial development.

Planning for early production from Waitsia-1 and Senecio-3 is under way.

"The further success in Waitsia-1, following discoveries in the Senecio-3 and Irwin-1 wells, has reconfirmed the potential of the north Perth Basin to deliver substantial volumes of commercial gas into the Western Australian domestic gas market. Further work is now underway to quantify the additional gas resource indicated by the thicker, better quality sands intersected in Waitsia-1," AWE managing director Bruce Clement said.

Given the Perth Basin is well served by infrastructure and pipelines and, subject to joint venture and regulatory approvals, AWE is targeting early production from Senecio-3 and Waitsia-1 wells within 12 months.

"We have commenced gas marketing and have held a number of meetings with potential customers for early stage gas production," Clement said.

"Preparations are well advanced to drill Waitsia-2, which is designed to evaluate the southern extent of the field and allow us to appraise some of the upside potential identified in Waitsia-1.

"In addition, the success at Senecio-3 and Waitsia-1 give us further confidence in additional exploration potential within the north-south corridor extending from L1/L2 down into L11," Clement said.

Following further evaluation and testing, it is expected that Waitsia-1 will be completed and suspended as a future production well with potential plans for future flow testing.

The discovery is 17km east of Dongara, which declared itself "gas-field free" at the weekend.

Waitsia-1 follows the successful Irwin-1 tight gas discovery well.

AWE and Origin have now added around 500Bcf of gas resources in the Perth Basin in recent months.