The Northern Territory Geological Survey (NTGS) is building 3D structural models of the greater McArthur Basin (Northern Territory, Australia). The models are generated from a series of 1D, 2D and 3D data. The present DIP contains an amended model based on the previous regional model of the Wilton package, amended on the western margin using new field data (completed 07/11/2015). In terms of digital data, the DIP contains 2D GIS objects, 2D cross sections and 3D digital objects grouped as wells, faults and horizons. These objects were used to build previous released models (Bruna and Dhu 2016) but are not necessarily used in the present model update. Newly considered data are summarised herein. The model currently provided in this update is the following: Regional model of the Wilton package, amended on the south eastern section of the Mallapunyah fault, in the Tanumbirini area (completed 15/06/2016) This report provides a short explanation of how objects were created and lists the names of these objects. The data objects and GOCAD project are all referenced in GDA 94 zone 53.

The Rosebery-Lyell 3D geological and geophysical model is an extension and refinement of previous MRT 3D models in the region. It expresses a new structural synthesis based on mapping and multiple cross sections produced by numerous geologists over several decades. It extends to a depth of 10 km within the area depicted at left. The model is constrained by 3D geophysical modelling using MRT's gravity and magnetic survey data coupled with drilling and rock physical property databases. This information has been used to derive uncertainty estimates for each element in the model volume. The model files also include nominal density and magnetic susceptibility estimates obtained for each voxel, thus incorporating intra-unit variations.

3D geological and geophysical modelling was used in conjunction with mineral potential modelling to assess unrealised Cu-Au potential in the Quamby area in the Eastern Succession of the Mount Isa Inlier. This report documents the process used by the Geological Survey of Queensland, including 3D modelling and geophysical inversion, to create a Common Earth Model (CEM) for 3D mineral potential modelling over the Quamby Project area. The area is divided into three main geological domains, the Mary Kathleen, Constantine and Soldiers Cap Domains (adapted from the North-West Queensland Mineral and Energy Province Report (NWQMEPR), Geological Survey of Queensland, 2011b). The Quamby Project area contains the major operating Ernest Henry Cu-Au mine as well as other significant Cu-Au projects and is highly prospective for a range of mineralisation styles including Cu±Au±Fe deposits and stratabound sediment-hosted Cu deposits. Mesozoic and Cenozoic sediments cover more than 70% of the project area. Although interpreted cover depths are generally less than 150m, much of the area remains under-explored. A 3D geological model was created using GOCAD and SKUA software incorporating new interpretations from recent mapping by the Geological Survey of Queensland (Geological Survey of Queensland, 2011b) as well as drillhole and seismic data. This 3D model was used as a starting model to constrain potential field inversions yielding 3D physical property models (density and magnetic susceptibility).

3D data for the Geoscience Australia Record 2009/029 - 3D Map and Supporting Geophysical Studies in the North Queensland Region

This model was produced by The South Australian Centre for Mineral Exploration Under Cover (CMXUC), a collaborative research initiative of the Government of South Australia and the University of Adelaide. In this area, basement is buried beneath Neoproterozoic-Recent cover, of the Eastern Officer, Arckaringa and Eromanga Basins. The depth to basement horizon, shows the complex geometry of the Munyarai Trough which forms a foreland to the uplifted Musgrave Block; the Marla Overthrust Zone and Ammaroodinna Ridge which were uplifted after the deposition of Cambrian to Silurian sedimentary rocks; the Middle Bore Fault Zone which was last active during deposition of the Arckaringa Basin and the Wintinna Trough. Large potential field anomalies have been observed in the Marla Region of Northern South Australia and have been used to define the northern limit of the Gawler Craton. This project’s aim was to model the source of those anomalies in order to understand the sources of those anomalies.

A regional scale structural and stratigraphic 3D model has been developed for the western Tamworth Belt within the New England Orogen in northeastern New South Wales. The western Tamworth Belt is bound by the crustal scale Hunter-Mooki and Peel-Manning Fault systems, which together form a wedge of deformed Devonian to Permian rocks. The model consists of broad lithological volumes representing Devonian, Devonian-Carboniferous, Carboniferous and Permian rocks that are folded and offset by numerous second and third order fault systems with minor intrusion by Permian granitoids. The model is based on a series of 2 dimensional cross sections developed based on the integration of surface mapping, 16 reflection seismic profiles as well as magnetic and gravity data. Interpretation confidence volumes are provided with the model to visually represent constraint location and constraint quality. The results of the modelling provide a basis for understanding the regional structural architecture and controls on mineral systems. The model illustrates the contrast in deformation style from the northern Tamworth Belt, relative to the southeast of the belt that is more structurally complex in terms of folding and faulting. The distribution of known hydrothermal mineral systems in the Tamworth Belt appear closely linked to the fault-architecture, with most occurring around steep west-dipping fault zones that intersect or splay from the Hunter-Mooki Fault at depth. Faults of this style are more common in the southeastern Tamworth Belt than they are to the north.

A 3D model of the Otway and Torquay basins has been produced at 1:250 000 scale as part of GeoScience Victorias state-wide 3D geological model. To date there has been a “knowledge gap” in the transition between the basement and basin environments. This regional scale integration of the basement and basin models addresses this gap and provides a regional framework within which more detailed work can be carried out in the future. The construction and integration of the basin model has involved both the interpretation and building of new faults and stratigraphic surfaces, as well as utilising existing stratigraphic surfaces and structural interpretations from previous studies, predominantly the Otway Basin HSA SEEBASE project by FrOG Tech (Jorand et. al., 2010).