Publications
Aitken, ARA., Betts, P.G., Weinberg, R.F., Gray, D., 2009. Constrained potential field modeling of the crustal architecture of the Musgrave Province in Central Australia: Evidence for lithospheric strengthening due to crust-mantle boundary uplift. Journal of Geophysical Research, in press.
Stewart, J.R., Betts, P.G., Collins, A.S., Schaefer. B.F., 2009. Multi-scale analysis of Proterozoic shear zones: An integrated structural and geophysical study, Journal of Structural Geology, In Press, doi:10.1016/j.jsg.2009.07.002.
Williams, H.A., Stewart, J.R. and Betts P.G. 2009. Imposition of a Proterozoic salient on a Palaeozoic orogen at the eastern margin of Gondwana, Gondwana Research, In Press.  doi:10.1016/j.gr.2009.06.006.
Aitken, A.R.A., and Betts, P.G., 2009. Multi-scale structural and aeromagnetic analysis to guide tectonic models: An example from the eastern Musgrave Province, Central Australia. Tectonophysics, Doi:1016/j.tecto.2009.07.007.
Betts, P. G., D. Giles, J. Foden, B. Schaefer, G. Mark, M. Pankhurst, C. Forbes, H. A. Williams, N. Chalmers, and Q. Hills., 2009. Mesoproterozoic plume-modified orogenesis in eastern Precambrian Australia, Tectonics, doi:10.1029/2008TC002325.
McLean, M.A., Wilson, C.J.L., Boger, S.D., Betts, P.G., Rawling, T.J., Damaske, D. 2009. Basement interpretations from airborne magnetic and gravity data over the Lambert Rift region of East Antarctica. Journal of Geophysical Research, 114, B06101, doi:10.1029/2008JB005650.
Williams, H.A., Betts, P.G., Ailleres, L. 2009. Constrained 3D modelling of the Mesoproterozoic Benagerie Volcanics, Australia. Physics of the Earth and Planetary Interiors 173 (3-4), 233-253.
Aitken, R.A., Betts, P.G. 2009. Constraints on the Proterozoic supercontinent cycle from the structural evolution of the south-central Musgrave Province, central Australia. Precambrian Research 168, 284-300.  doi:10.1016/j.precamres.2008.10.006.
Williams, H.A., Betts, P.G. 2009. The Benagerie Shear Zone: 1100 Myr of reactivation history and control over continental lithospheric deformation. Gondwana Research 15, 1-13.  doi:10.1016/j.gr.2008.06.006.
Aitken, R.A., Betts, P.G. Gray, D., Rye, S. 2008. Integration of aeromagnetic data and structural observations in the Deering Hills region of the Musgrave Province. Australian Journal of Earth Sciences 55, 1127-1138.
Forbes, C.J. Betts P.G, Giles, D., Weinberg, R. 2008. Reinterpretation of the tectonic context of high-temperature metamorphism in the Broken Hill Block, NSW, and implications on the Palaeo- to Meso-Proterozoic evolution. Precambrian Research 166, 338-349.
Betts, P.G., Giles, D., Schaefer, B.F., 2008. Comparing 1800-1600 Ma accretionary and basin processes in Australia and Laurentia; possible geographic connections in Columbia. Precambrian Research 166, 81-92.
McLean, M.A., Rawling, T.J., Betts, P.G., Phillips, G. and Wilson, C.J.L 2008. Three-dimensional inversion modelling of a Neoproterozoic basin in the southern Prince Charles Mountains, East Antarctica. Tectonophysics 456, 180-193.
Aitken, R.A., Betts, P.G. 2008. High-resolution data over central Australia assist Grenville-era (1300-1100 Ma) Rodinia reconstructions. Geophysical Research Letters 35, L01306, doi:10.1029/2007GL031563.
Betts, P.G. Giles, D., Schaefer, B.F., Mark, G., 2007. 1600-1500 Hotspot track in eastern Australia: implications for Mesoproterozoic continental reconstructions. Terra Nova 19, 496-501.
Forbes, C.J., Giles, D., Betts, P.G., Weinberg, R., Kinny, P.D. 2007. Dating prograde Amphibolite and Granulite metamorphism using in situ Monazite U-Pb SHRIMP analysis. Journal of Geology 115, 691-705.
Williams, H.A., Betts, P.G. 2007. Imaging links between lithospheric architecture and surface geology in the Proterozoic Curnamona Province, Australia Journal of Geophysical Research 112, B07411, doi:10.1029/2007JB004966.
Betts, P.G., Williams, H.A., Stewart, J., Ailleres, L. 2007. Kinematic analysis of Aeromagnetic data: Looking at geophysical datasets in a structural context. Gondwana Research Newsletter Correspondence 11, 582-583.
Research Grants
- Discovery Projects
The Initiation of Early Palaeozoic Subduction in Eastern Australia and North America: causes and effects
Total ARC funding: $180,000 (2007-2009)
Chief Investgators: Prof JD Foden; Dr BF Schaefer; Dr PG Betts; Dr MA Elburg; Prof GA Jenner; A/Prof CR Kincaid
Subduction is the return of cold, dense, oceanic lithosphere to the mantle and is one of the key dynamic elements of the plate tectonic paradigm. It is this process that is responsible for the 'Pacific Ring of Fire'. It is the root cause of many key geological processes and is a primary control of some of the earth's largest‑scale physiographic features, including deep‑sea trenches and mountain ranges. Using the important record of Cambrian in eastern Australia and in the comparable Canadian Atlantic margin, this project will look at the causes and impact of the earliest stages of subduction as it first developed in the western Pacific and pre‑cursor Atlantic 500 million years ago.
Linkage Projects
Unearthing the Marginal Terranes of the South Australian Craton: Keystone of Proterozoic
Total ARC funding: $430,000 (2008-2010)
Partner Organisation: Primary Industries and Resources South Australia
Chief Investigators: Dr PG Betts; Prof D Giles; Dr G Baines; Mr M Fairclough; Dr BF Schaefer
This project will investigate the buried geology of vast regions of northern South Australia that is likely to be compatible with rocks that host enormous mineral wealth including the giant Broken Hill and Olympic Dam deposits. We will access these buried rocks using a program of on‑shore scientific drilling that will provide the ground truth for multi‑million dollar federal and state government funded geophysical data acquisition. Results will help identify prospective mineral belts and determine the processes responsible for their formation.
- Australian Society of Exploration Geophysicists Research Foundation
Defining the margins of Australia’s ancient geological cratons from gravity and magnetic fields
Total funding: $30,000 (2009-2011)
Investigators: Dr PG Betts; Dr Laurent Ailleres; Mr Brenton Crawford (PhD student)
It has now been demonstrated that several of Australia’s most prominent mineral belts (e.g., Olympic IOCG domain in the Gawler Craton) occur along the major crustal boundaries that occupy the location of ancient collisional zones at the margin of cratonic boundaries. Craton boundaries may have been favoured sites for mineralisation because they are likely to reflect ancient plate margins characterised by elevated heat flow, have lithospheric penetrating faults systems able to tap the deep crust and mantle lithosphere, and in many case may have occupied the position of ancient arc, which have all shown on the modern Earth to favour mineral development of mineral districts.
This project aims to address the issue of the distribution and geometry of these plate margins using analysis of regional potential field datasets to constrain their 3D geometry and to determine the connectivity between faults at the surface and deep crust structure. This will assist regional targeting and also assist in the development of new geodynamic models that will assist understanding the setting of mineral systems.
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SEG Hugo Dummett Memorial Mineral Discovery Fund
Combined Geological and Potential Field Inversions: Using Geological Uncertainty in Implicit Modelling Applications.
Total funding: US$2,500 (2009); Geoscience Victoria - $10,000
Investigators:Dr Laurent Ailleres; Dr PG Betts; Mr Mark Lindsay (PhD student)
Over the past few decades, the increase in accessibility to high computing power and complex algorithms has made 3D geological modelling more accessible. Numerous models have been built from the plate scale to the mine scale. Unfortunately, the use of explicit modelling packages requires significant amounts of interpretation and extrapolation in the 3rd dimension and is highly subjective, so much so that it is very often not reproducible. The degree of uncertainty is high, which cannot be determined mathematically as the modelling process involves manual editing. Within the last few years an implicit geological modeller, 3D GeoModeller, was developed. While the modelling technique does not currently allow for uncertainty calculations, it will be used (and a test has been successfully completed already) to generate multiple geological architectures calculated from the same input data (although slightly varied to take into account and propagate field measurement errors). This will allow estimation of geological variability within a finite region and estimate the uncertainty within the resulting best probable geological model. In parallel, a subset of the models calculated above will be used for a-priori models for combined inversions of gravity and magnetic potential fields. The subset will be defined by an overall low geological uncertainty and a low misfit while comparing forward calculation of the potential fields and observed data. After potential inversions, the models will satisfy a low geophysical misfit. However, they may not satisfy the input geological data anymore and some of them should be rejected on geological grounds. This will require the development of geological penalty functions to assess the models geological predictions against the input data. Ultimately, the geological penalty functions will be integrated into a combined inversion process involving gravity and magnetics potential fields and geology. This new technique will be tested on synthetic models as well as real geological and geophysical datasets. We propose to build a 3D geological model along the Moyston Fault in Western Victoria.
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