Degree in Geology or Geophysics or other kinds Geoscience degree.
Logistical support for this project will be provided by the Geological Survey of Western Australia
Geological Survey of Western Australia
This research project provides the opportunities for a student to obtain skills and experience in the interpretation of aeromagnetic data as widely used by the mining, petroleum and environmental industries.
Detailed aeromagnetic datasets from the Yilgarn Craton clearly delineate responses from mafic dykes. These data show that the ‘conventional’ story of dyke intrusion is too simplistic, especially in the western and southern parts of the Craton, and there are many more distinguishable dyke-forming events than previously realised. An example of aeromagnetic data clearly showing multiple generations of dykes is shown in the figure.
The scientific objective/problem associated with the project is the establishment of a refined chronology of dyke-forming events in the SW Yilgarn Craton. The project consists of a series of related components:
High-resolution aeromagnetic datasets have been obtained from various regions of the southwestern Yilgarn Craton. Key datasets will be selected for interpretation, concentrating on responses from dykes to establish a provisional model of swarms/intrusive events. Dykes will be assigned to swarms based on their trend, magnetisation direction and cross-cutting relationships.
Based on the interpretation, field sampling of selected dykes/screen will occur, to obtain samples for analysis of their petrophysical and magnetic properties. This will involve analysis of magnetic mineralogy, if possible establishing the timing of one or more phases of magnetisation.
Using (simple) modelling software the magnetic anomalies associated with the dykes will studied. Particular aims are to confirm magnetisation directions found in samples and to model observed ‘cross-cutting’ relationships to confirm relative ages.
These various sources/types of information must be integrated to formulate an interpretation of the intrusive history of the southwestern Yilgarn Craton.
Hallberg, J.A., 1987. Postcratonization mafic and ultramafic dykes of the Yilgarn Block. Australian Journal of Earth Sciences, 34, 135-149.
Harris, l.B. and Li, Z.X., 1995. Palaeomagnetic dating and tectonic significance of dolerite intrusions in the albany Mobile Belt, Western Australia. Earth and Planetary Science Letters, 131, 1453-164.
Parker, A.J., Rickwood, P.C., Ballie, P.W., McClenaghan, M.P., Boyd, D.M., Freeman, M.J., Pietsch, B.A., Murray, C.G. and Myers, J.S., 1987. Mafic dyke swarms of Australia. In, Halls, H.C. and Fahrig, W.F., (eds), Geological Association of Canada Special Paper 34, 401-417.
Tucker, D.H. and Boyd, D.M., 1987. Dykes of Australia detected by airborne magnetic surveys. In, Halls, H.C. and Fahrig, W.F., (eds), Geological Association of Canada Special Paper 34, 163-172.