Kimberlite and Kimberlitic Intrusives of Southeastern Australia

John Ferguson
Bureau of Mineral Resources, Geology and Geophysics, PO Box 378, Canberra, Australia, 2601

Summary: Fifteen widely separated occurrences of kimberlite and kimberlitic rocks are now known in south-eastern Australia. Those that have been satisfactorily dated isotopically give ages ranging from Permian to Late Jurassic. One occurrence exhibits an intimate spatial association with carbonatite. The classification of these rocks as ‘kimberlitic’ is partly based on their mode of emplacement, and particularly on the presence of crust/mantle inclusions. Compared with African kimberlitic magmas, the southeastern Australian examples have lower incompatible-element contents. These differences are interpreted as representing slightly greater degrees of partial melting of a four-phase Iherzolite assemblage at shallower depths (∼ 65 km) than typical African kimberlite magma.

Mineralogical Magazine; June 1980 v. 43; no. 330; p. 727-731; DOI: 10.1180/minmag.1980.043.330.05
© 1980, The Mineralogical Society
Mineralogical Society (www.minersoc.org)