Exploring for the Future

Assessing soil fertility and mineral potential over the Barkly Tableland

As part of the Exploring for the Future program, scientists from Geoscience Australia are leading focused studies in the prospective region between Tennant Creek and Mt Isa to identify potential resources by assessing the chemical composition of soils.

In 2017, field crews collected soil samples from 780 sites, some from harsh remote areas where access is only possible by helicopters, to analyse the chemical elements within the soils using state-of-the-art techniques.

Soil sampling surveys are an excellent low-impact means of identifying the mineral potential of examined areas as they can indicate what lies deep beneath the Earth. On top of that, the survey results provide a basis for informed decision making about regional land use and agriculture. One of the analytical methods employed, Mobile Metal Ion analysis (MMI), emphasises mobile forms of chemical elements loosely attached to soil particles, including elements regarded as essential nutrients for plant growth and animal health: calcium, copper, iron, potassium, magnesium, manganese, phosphorus and zinc.

The data provide insight into the fertility of soils, which can support sustainable crop production and inform cattle grazing management over areas such as the Barkly Tableland. For example, the data has identified areas with various levels of phosphorus in the soil (see map), an essential element for cattle health. This has a potential to help farmers effectively manage cattle health via phosphorus supplementation.

Complete sets of maps, including georeferenced images ready for use with compatible mobile apps are available from the Geoscience Australia website.

The extensive soil sampling survey was led by Geoscience Australia in collaboration with the Northern Territory Geological Survey and the Geological Survey of Queensland.

For more information visit the Geoscience Australia website or email eftf@ga.gov.au.