Northern Australia Geochemical Survey Data release 1 – Total (fine fraction) and MMI™ element contents

Tennant Creek and Mt Isa are the preeminent mineral resource hubs for the Northern Territory and Queensland. The region between these two hubs is a vast prospective exploration frontier, covered by a thin veneer of sediments, which has been overlooked for exploration in the past. Regional soil sampling surveys are an excellent means of identifying the mineral potential of such regions as they can reveal what lies beneath the cover. Geoscience Australia, as part of the Federal Government’s Exploring for the Future program, undertook an extensive soil sampling survey in collaboration with the Northern Territory Geological Survey and the Geological Survey of Queensland. Catchment outlet sediment samples were collected at 776 sites (including duplicates) and analysed for their elemental composition. The data reveal areas with future potential for base metals including copper. The data are also valuable for agricultural management, allowing farmers to measure soil fertility to maintain sustainable crop production and inform cattle grazing management over the Barkly Tablelands region of the Northern Territory. This information can be used to guide safe and responsible agricultural development in the future. Further, the survey establishes robust geochemical baseline data sets relevant to many environmental issues which can be utilised in development decision making. The survey was undertaken over a period of two months utilising two helicopters from Northern Australia Helicopters based in Katherine. Samples were prepared for analysis over five months by an indigenous company supervised by Geoscience Australia staff at the Centre of Appropriate Technology in Alice Springs. Analysis of the samples was performed by Geoscience Australia in Canberra and SGS Australia mineral services in Perth. This data release includes (1) information on the sampling sites, (2) bulk sample properties (Munsell colours, pH, electrical conductivity), (3) results of the total chemical analyses of the fine (<75 m) fraction of the samples (XRF, ICP-MS) and (4) results of the partial leach analyses of the Mobile Metal Ion™ (MMI™) extractions (0–2 mm fraction, ICP-MS). Included is also a set of digital images of geochemical maps based on this dataset. This dataset is the first of a series of staged data releases from the Northern Australia Geochemical Survey. Relevant data, information and images are available through the GA website (http://www.ga.gov.au/eftf/fis/nags).