Mineral Resources (MinRes) and Norwest Energy said that the Lockyer Deep gas field discovered by the duo in the onshore Perth Basin in Australia in September 2021 could be larger than expected.

The gas discovery was made by the EP368 joint venture partners through the drilling of the Lockyer Deep-1 discovery well. During its flow testing, the well flowed 117MMscf/d, said Norwest Energy.

MinRes is the operator of the Lockyer Deep gas field through its subsidiary Energy Resources with an 80% stake. Norwest Energy holds the remaining 20% stake.

The gas discovery is estimated to contain 87.5% methane and 3.9% CO2.

The analysis of pressure data showed free water levels in the range of 4,458m and 4,620m.

Norwest Energy stated: “Semi-qualitative rock typing of drilling cuttings indicates that additional gas pay may exist, over and above the identified via preliminary petrophysical analysis, with potentially effective reservoir down to 4058 metres.”

According to the company, because of the estimated deeper level of free water and based on its post drill structural interpretation, the potential resource area has been enlarged to 100km2. Previously, the size of the Lockyer Deep gas field was estimated at 92km2.

Norwest Energy managing director Iain Smith said: “The post-well analysis confirms that we have encountered an exceptional, high-pressure gas reservoir with good evidence to support a very significant gas column that justifies a comprehensive appraisal programme for which Norwest is well funded.”

MinRes and Norwest Energy plan to take up additional appraisal drilling and 3D seismic, which will commence towards the end of 2022.

The appraisal programme will include drilling of two wells that will target the Lockyer Deep and North Erregulla Deep structures.

The first of the wells, North Erregulla Deep-1 will evaluate the structural high, nearly 8.5km southeast of the Lockyer Deep-1 discovery well.

A second well, dubbed Lockyer Deep-2, will be drilled northeast and downdip from the gas discovery well.

Norwest Energy revealed that two more wells are being planned, with their locations to be based on the findings of Lockyer Deep-2 and North Erregulla Deep-1.

In parallel with the drilling programme, MinRes intends to acquire 3D seismic across the permits, which will cover Lockyer Deep and five other leads.

MinRes is expected to use the gas produced from the Lockyer Deep gas field for powering its mine sites instead of using diesel generators.