Heavy Mineral Sands
Geophysics for Heavy Mineral Sands
Stephen Mudge has been actively developing and applying geophysical techniques to ilmenite, rutile, zircon and monazite heavy mineral sands exploration since 1981. A variety of geophysical methods have been tested across a number of palaeo-beach placer deposits in Australia and Eastern USA. In addition, a range of data-processing techniques have been developed and tested in an attempt to detect the generally weak geophysical responses characteristic of these deposits.
As of mid-2004, the fastest and most cost-effective geophysical method for broad-area exploration for beach placer heavy mineral sands deposits is surveying with low-level, high-resolution aeromagnetics and radiometrics. Specialised processing techniques are applied to the aeromagnetic data using TargetMapTM in order to resolve the weak magnetic responses of ilmenite and iron-oxides which are often associated with the deposits. Similar processing is applied to the radiometric data to detect near-surface occurrences of monazite. A full description of these techniques is given in Mudge and Teakle (2003).
A review of other geophysical methods applied to heavy mineral sands exploration can be found in Mudge (1994). Details of TargetMapTM can be found elsewhere on this web site, including an example of reprocessed total magnetic intensity data from the Kulwin heavy mineral sands deposit, near Ouyen, in the Murray Basin of Victoria, Australia.
References
Stephen Mudge has two leading publications in this area:
Mudge, S. T., 1994. Geophysical surveys of the Eneabba heavy-mineral sand field, Eneabba, Western Australia. In, Dentith M.C., Frankcombe, K. F., Ho, S. E., Shepherd, J. M., Groves, D. I. and Trench, A., (Eds.), Geophysical Signatures of Western Australian Mineral Deposits. Australian Society of Exploration Geophysicists Special Publication 7, Geology and Geophysics Department (Key Centre) and University of Western Australia Extension Publication 26, p 427 - 431.
Mudge, S, and Teakle, M, 2003. Geophysical exploration for heavy-mineral sands near Mindarie, South Australia. In Dentith M.C. (Ed.), Geophysical Signatures of South Australian Mineral Deposits. Centre for Global Metallogeny, The University of Western Australia, Publication 31, and Australian Society of Exploration Geophysicists, Special Publication 12, and Primary Industries & Resources South Australia, p 249 - 255.