Steven M Hill

• BSc(Hons) (University of Melbourne 1992); PhD (Australian National University 2002)
• Chief Scientist at Geoscience Australia

We conducted the analysis of the chemistry of leaves from Eucalyptus camaldulensis (Australian River Red gums) growing in a creek system that crosscuts known Pb-Zn mineralization to assess the influence of cyclic El Niño and La Niña weather patterns on biogeochemical exploration. Samples were collected over two periods: in 2005 immediately after a...

Transported and typically weathered material that extends over much of Australia presents a challenge for the successful application of surficial geochemical exploration methods. The Tunkillia Au-prospect in the Gawler Craton, South Australia provides a case study where unconsolidated and potentially laterally transported aeolian and alluvial sedim...

Salinisation of floodplains along the Murray River is a significant environmental and social problem in south-eastern Australia that can be expensive and time-consuming to monitor. The potential of plant biogeochemistry as an environmental monitoring tool, specifically its innovative application to groundwater salinity detection, is explored in thi...

The antiquity of the Australian landscape has long been the subject of debate, with some studies inferring extraordinary longevity (>10 ⁸ Myr) for some subaerial landforms dating back to the early Palaeozoic. A number of early Permian glacial erosion surfaces in the Fleurieu Peninsula, southeastern Australia, provide an opportunity to test the noti...

We consider how our society can use data, information and knowledge of the Earth under a broad definition of geoscience to better connect with the Earth system. This is important in our changing world, in particular how geoscience contributes to our response to the societal impacts of the COVID-19 pandemic. Ultimately, informed decisions utilizing...

YouTube link to full presentation video: https://youtu.be/1Tgia_CxwqQ

The importance of trusted, high-quality and relevant science to inform and advise governments and our communities is greater now than it ever has been. This is particularly the case for geoscience and its role to drive people's connection to the Earth as the place where we live and obtain the resources we use to live our lives. Our community's reco...

The Mount Gee Sinter and the Radium Ridge Breccia within the Mount Painter Inlier, South Australia, preserve evidence of a hydrothermal event peaking during the Late Devonian (ca 365 Ma). Prior to this study, limited data relating to this event were available, but our results of 846 LA-ICPMS U–Pb monazite analyses indicate the timing of this hydrot...

The sediment-hosted uranium deposit at Four Mile West is buried by 130–150 m of sediments yet has a landscape as well as a surficial geochemical and biogeochemical expression of the mineral system. The landscape expression includes exposure of stratigraphy with now-oxidised redox overprinting (including ‘roll-fronts’) equivalent to those in the bur...

This study presents new geochemical and mineralogical data collected on 13 drill holes across the South Australian part of the Eromanga Basin, with a focus on the Lower Cretaceous Cadna-owie Formation, Bulldog Shale, Coorikiana Sandstone and Oodnadatta Formation. Mineralogical and geochemical data are used to determine the provenance of the sedimen...

Sediments comprising the Radium Ridge Breccia, a stratigraphic unit recognised within the Mesoproterozoic Mount Painter Inlier, are now re-interpreted as Lower Cretaceous (previously interpreted to be Paleozoic) periglacial deposits with associated glacial and pro-glacial facies that extend into adjacent Eromanga Basin sediments. The interpretation...

The presence of deformation bands in Upper Cretaceous–Pleistocene sediments of the St Vincent and Lake Eyre basins, South Australia supports the occurrence of intraplate normal and reverse faulting in this region throughout the Cenozoic. Current tectonic models for the development of this region lack structural evidence and underestimate the role a...

The Early Cretaceous interbedded sandstone, siltstone and mudstone of the Cadna-owie Formation and the reduced mudstone of the Bulldog Shale overlying the Prominent Hill IOCG deposit in South Australia (total tonnage: 140 Mt. @ 1.2% Cu and 0.5 g/t Au; OZ Minerals Limited 2017) are shown to preserve Cu concentrations up to 5043 ppm Cu. These cover s...

A first pass workflow for placing cover sequence materials into four broad lithological groups using A–CNK–FM (Al2O3–CaO + Na2O + K2O–Fe2O3+MgO) and A–CN–K (Al2O3–CaO + Na2O–K2O) ternary diagrams in conjunction with the SiO2 vs Al2O3, Fe2O3 and CaO plus the Ca versus Sr XY diagrams has been derived from lithological logging and laboratory whole-roc...

Deformation bands are common fault-related strain features found in upper crustal granular highly porous sedimentary rocks. However, the majority of research has focused on siliciclastic-related case studies, resulting in a knowledge gap surrounding the nomenclature and implications of carbonate-hosted cataclastic bands. We present a systematic cas...

The late Palaeozoic Cape Jervis Formation of the Troubridge Basin in southern South Australia provides a sedimentological record of the glacial environment during the PermoCarboniferous glaciation. The sedimentary sequence is divided into five informal units that comprise the Cape Jervis Formation, and preserve sedimentological features that have b...

Cover sequence materials of the Bulldog Shale and underlying Cadna-owie Formation within the Eromanga Basin (South Australia) that overlie the Prominent Hill iron oxide-copper-gold (IOCG) deposit are evaluated for their potential to host a geochemical expression of the underlying mineral system and thereby as geochemical exploration sampling media....

We report on the geochemistry of 215 regolith carbonate rocks collected across the Yorke Peninsula, South Australia in order to evaluate the potential of regolith carbonates as a geochemical sampling media for buried Cu mineralization. The Yorke Peninsula forms the southern part of the Olympic Domain iron-oxide‑copper‑gold (IOCG) mineral province a...

We report on the results of a regional scale biogeochemical sampling program conducted on the Yorke Peninsula, South Australia, utilising four locally occurring Eucalyptus species with mallee-form. Our purpose is to determine if there is an empirical relationship between Cu accumulation in the mallee leaves and elevated Cu in the underlying basemen...

We present whole rock and strontium isotope geochemistry from geological profiles from the Yorke Peninsula in South Australia and provide a geochemical means of discriminating between Cenozoic marine carbonate-bearing rocks and Quaternary pedogenic carbonate-bearing rocks. Pedogenic carbonate-bearing rocks (commonly referred to as calcrete) are pot...

Ferricrete – sediment cemented by iron oxides and hydroxides – is common in subaerial weathering environments around the world. Formed under alternating oxidising and reducing conditions, ferricretes record pedogenetic processes of translocation and concentration of iron and trace elements in the soil. Given their stability and high preservation po...

UNCOVERING The Western Gawler Craton Margins

The Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) has the goal of mapping the electrical resistivity of the Australian lithosphere to constrain the geodynamic framework of the continent. Between August 2014 and May 2015, 125 long-period magnetotelluric (MT) data will be collected across the Gawler Craton and the south-easte...

Tier 1 mineral resource discoveries are critical to maintaining Australia’s, and indeed the world’s, mineral resource inventory without continuing decline in the grade of mined resources. Such discoveries are becoming less common because, increasingly, remaining prospective, under-explored areas are obscured by deep, barren cover. We argue that imp...

INTRODUCTION: Spencer Gulf, the larger of two triangular gulfs in South Australia, is up to 200 km wide at its mouth, and extends northward for almost 400 km. It forms a shallow marine depression only some 50 m deep in the south, shallowing into wide sea floors less than 15 m deep with a central channel a little deeper than 20 m over most of its no...

The eastern Gawler Craton hosts the giant Olympic Dam iron oxide copper gold (IOCG) deposit as well as other large IOCG deposits (i.e. Prominent Hill and Carrapateena). The region is covered by a thick sequence of Mesoproterozoic to Cenozoic sedimentary and volcanic rocks making the region difficult to explore using conventional methods. The projec...

Spinifex (Triodia spp.) grasslands cover vast areas of arid Australia, across a variety of soils and landscapes. These grasses are deep rooted and long lived, hence have great potential as a biogeochemical sampling medium for mineral exploration. This study discusses the results of analyses of Triodia pungens and Triodia scariosa from field sites o...

Regolith carbonates are common in soil profiles in the arid to semiarid areas of southern and central Australia. Extrinsic sources are now inferred to be the dominant source of Ca even as far inland as Alice Springs in central Australia. This study of Ca sources in a near coastal 2 m deep profile at Clarendon, South Australia, and two inland 4- and...

Deposits of proximal dust-derived alluvium (alluvial loess) within the catchments of the now semi-arid Flinders Ranges in South Australia record regionally synchronous intervals of fluvial entrainment, aggradation and down-cutting spanning the last glacial cycle. Today, these floodplain remnants are deeply entrenched and laterally eroded by ephemer...

Terrace remnants of late Pleistocene fine-grained valley-fill deposits (Silts) deeply entrenched by ephemeral traction load streams in arid areas remain a puzzle. They have been attributed to a variety of origins ranging from lacustrine to alluvial floodplains. We here report a centimetre-scale multi-proxy study of a 7 m section of Silts in the sem...

Vegetation sampling is an effective mineral exploration technique in areas of transported cover in the Tanami Gold Province where other techniques have been of limited success. This research tests the ability of plants to show signatures of mineralisation as well as the optimum scale of sampling for first-pass mineral exploration surveys. The semi-...

Gold mineralization at the Titania Prospect in the Tanami Desert Region is buried by transported regolith including mixed aeolian and sheetflow deposits over palaeodrainage sediments. This prospect is the only example of discovery through significant thickness of transported regolith and therefore provides an important site for developing an unders...

Termitaria (termite mounds) are a widespread and abundant component of tropical savannah ecosystems in northern Australia. Despite their abundance very little systematic research has been carried out on the application of termitaria sampling to mineral exploration in this region. Multi-element biogeochemistry of termitaria from species with the mos...

The Jerrabattgulla Creek basalts are in the upper catchment of the Shoalhaven River of southeastern New South Wales. The basalts erupted into a narrow, north-draining valley and modified the local drainage system, re-routing the paleo-Jerrabattgulla Creek, preserving a series of sub-basaltic quartzose gravels with silcretes in the paleovalley. The...

A major challenge for mineral explorers is to efficiently detect mineralisation beneath the weathered cover that extends across the landscape. Determination of the elemental composition of plants (biogeochemical exploration) can aid in the detection of buried ore deposits due to their root penetration through the weathered cover. At the coyote pros...

This Guide is designed to assist mineral explorers working in the regolith-dominated terrains of the central region of the Gawler Craton in South Australia, in particular those areas of weathered bedrock where dominantly terrestrial deposits form patchy and comparatively thin (<100 m) cover. From a mineral industry perspective, the Gawler Craton is...

This Guide is designed to assist mineral explorers working in regolith-dominated regions of the Curnamona Province. Although the information presented may be applied across the Curnamona region, the focus is on the southern Curnamona Province where there has been the greatest number of regolith studies. The Guide provides an introduction to the reg...

Detailed regolith-landform map of Hotel Paddock, Fowlers Gap Arid Zone Research Station, New South Wales, Australia.

Part of the Broken Hill 1:25,000 regolith-landform map series published by CRC LEME (Perth) through Geoscience Australia map production

Thick sediment cover impedes exploration in some of the most prospective areas away from bedrock outcrop in the Proterozoic Curnamona Province. The objectives of the CurnaMinEx project are to test the effectiveness of surface techniques to locate buried mineral deposits. An effective technique would reduce exploration costs associated with the curr...

The widespread regolith carbonates of the Australian continent are a potential sink for CO2. We have used Sr isotopes to investigate the source of the Ca in regolith carbonates that cover approximately 1.6×106 km2 of inland Australia. 87Sr/86Sr ratios for nearly all the carbonates were in the range 0.7094 to 0.7211. The results show that only about...

Part of the Fowlers Gap 1:12,500 regolith-landform mapping series published through CRC LEME. The approach here was to map each paddock within the Fowlers Gap Arid Zone Research Station, western New South Wales, Australia

Published through CRC LEME as part of the Fowlers Gap Arid Zone Research Station 1:12,500 regolith-landform map series.

SUMMARY The Thomson Orogen, which underlies sediments of the Great Australian Basin in northwest New South Wales, is the last major greenfields terrain in NSW. The Orogen has potential for magmatic arc and ocean- crust related gold and base metal deposits. However, the basin cover presents a significant impediment to exploration. The Thomson Orogen...

The oldest bedrock in the local area includes Ordovician metasediments of the Adaminaby Group (Lewis et al. 1994), which outcrop to the east of the mapping area. These are tightly to isoclinally folded and display a prominent axial plane cleavage that is typically parallel to bedding. These are intruded by granitoids of the Berridale Batholith, pri...

Bedrock within the area is predominantly, but not exclusively, exposed within the high points of the landscape, expressed as north-northwest trending hills and ranges. The highest points within the inliers are the Mt Browne and Mt Poole summits, with elevations of 274 m and 263 m, respectively. Surrounding these elevated areas are low undulating ba...

Ongoing research by CRC LEME and the NSW Geological Survey is addressing these challenges in the Tibooburra-Milparinka area. Research is being conducted on using the widespread regolith carbonate accumulations (RCAs), which include calcrete and dolocrete, to provide a regional geochemical context across this region. Over 300 RCAs samples have been...

detailed regolith-landform map from within the Tibooburra Inlier 1:25,000 regolith-landform map. Important for showing scale influence on mapping presentation but also the extra detail that can be brought into regolith:landform maps. This area is important as it contains some outliers of Au-bearing Mesozoic cover over the Tibooburra Inlier bedrock...

Originally set up as a 2nd year undergraduate field teaching area, this map was produced as a teaching guide. Unit descriptions are published in Hill & Roach 2005 CRC LEME conference abstract.

The oxygen isotopic composition (δ18O) of the cement of a silcrete sample from the “Cordillo silcrete” (Late Eocene/Early Oligocene) of Lake Eyre Basin (Australia) was investigated. The massive structure of the silcrete outcrop and the absence of pedogenic features suggest that this silcrete formed by precipitation from groundwater. In order to avo...

White Dam was chosen as the study site for the reasons that the mineralisation is poorly expressed in existing company assay results and that most of the mineralisation essentially occurs under transported cover. The techniques used in this study have been able to significantly improve the detection of Au and Cu with respect to mineralisation, espe...

The landscape of the region is part of the bedrock-dominated Olary Ranges and the flanking regolith- dominated lowlands associated with the Lake Eyre Basin and Murray Basin. The study area contains the major regional drainage divide between the Murray Basin (Murray-Darling catchment) to the south, and the Lake Eyre Basin (Lake Frome catchment) to t...

INTRODUCTION The depth of the regolith and how this measurement varies across the landscape is a fundamental attribute in the characterisation of the regolith, having many applications in both mineral exploration and natural resource management. The development of efficient, economical and accurate methods for determining the 3D architecture of reg...