Adavale Basin hydrogen, mineral potential at heart of Geoscience Australia project

The project is combining decades-old seismic data with cutting edge scientific data to take another look at the potential of the basin to yield up resources that could support Australia's energy transition.

The under-explored sedimentary basin is large and relatively old, deposited in the Devonian period approximately 419 to 358 million years ago, and buried under the younger Galilee Basin, which means there are no outcrops, making it challenging to study and gain an understanding of its potential resources.

The Data Driven Discoveries program, which is collaborating with the Geological Survey of Queensland, has already reprocessed approximately 2350 kilometres of seismic data from the Adavale Basin acquired between the 1960s and 1980s, and is applying technological advances to improve the imaging.

That will help program leaders decide where to drill a new stratigraphic well to test interpretations and models.

According to the Geosciences Australia webpage, the program is supporting the federal government's plan to achieve net zero emissions by 2050, targeting hydrogen storage, groundwater and minerals.

It said hydrogen gas can be stored in very large quantities underground in human-created salt caverns, and the basin's Boree Salt deposit was the only known thick salt accumulation in eastern Australia, but relatively little was known about its extent and size.

"Salt bodies are also a potential source of renewable geothermal energy," the page said.

"The thermal conductivity of salt makes it an excellent medium for storing and transmitting heat, which can be used for power generation.

"However, more investigation is needed to fully understand the extent and size of salt bodies in the Adavale Basin, as well as their geological controls, before their potential for renewable energy can be fully realised."

The basin is already a proven hydrocarbon basin, hosting the producing Gilmore Gas Field, but more exploration is needed to identify and develop additional hydrocarbon resources.

Basins like Adavale can host a variety of mineral deposits - copper, zinc and cobalt, critical to produce wind turbines and electric vehicle batteries - which the program's seismic data may help identify.

The project will also sample deep groundwater resources for the first time to understand the composition and connectivity of groundwater resources, to aid in the management and sustainable use of groundwater resources.

The project will use seismic reflection data, which involves generating sound waves that are sent into the subsurface and then recording the reflected waves that bounce back to the surface.

Vibroseis trucks will be used, which is described as non-invasive and very similar to a medical ultrasound scan.

It involves 10 to 15 4WD vehicles, three to four Vibroseis trucks, and a large recording truck to retrieve and process the information..

The trucks travel slowly, on the edge of the road, and only need to traverse along the road once. The truck's vibrations sound and feel like a road train passing by.

A drilling site will be identified through the seismic surveys undertaken in 2023, and the seismic reprocessing and chemostratigraphy undertaken in 2022 and 2023.

Drilling will be by either a rotary mud or diamond drilling method to recover rock chips or continuous drill core, and the footprint of the ground disturbance for drilling operations will be a cleared pad of approximately 50 by 50 metres.

The page says drilling will be "carefully supervised and monitored to avoid disturbance to surface water and aquifers, and all sites will be rehabilitated after drilling according to best practice".

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