Subduction model for the origin of some diamonds in the Phanerozoic of eastern New South Wales

Refining accretionary orogen models for the Tasmanides of eastern Australia

“…The southern Tasmanides Barron et al 1994Barron et al , 1996Griffin et al 2000). In essence, this model suggests that in a cold descending slab, the field of diamond stability is unusually high at $80-100 km depth, and can produce both eclogitic and peridotitic diamonds.…”

“…In essence, this model suggests that in a cold descending slab, the field of diamond stability is unusually high at $80-100 km depth, and can produce both eclogitic and peridotitic diamonds. Barron et al (1996) suggested that diamonds were only preserved by the termination of subduction, to be sampled later by younger magmas.…”

“…comm. to Barron et al 1996). Another group B diamond from Copeton has a 39 Ar/ 40 Ar clinopyroxene age of 326 AE 43 Ma (Late Devonian (Famennian) to early Permian (Artinskian)) (Davies et al 2002).…”

Paleogeothermal gradients in Australia: Key to 4‐D lithosphere mapping*

“…This is seen in Figure 2, where Jugiong and Bingara results lie closer towards the EMAC Mesozoic geotherm than the Walcha and Tasmanian results. By not referring to published data that enlarges the view beyond a simplistic SEA geotherm for eastern Australia, O'Reilly et al (1997) restrict the potential influence of geotherm variability for evaluating a region well-known for unconventional diamond deposits (Barron et al 1996;Sutherland 1996). …”

Diamonds from Wellington, NSW: insights into the origin of eastern Australian diamonds

“…Further resorption may have frosted the inclusion pits. Barron et al (1994Barron et al ( , 1996 suggested that the pits are negative imprints of garnet and other mineral grains that grew with the diamonds in a solid state. However, this is unlikely as the shapes of the pits do not reflect the shapes of the mineral inclusions preserved in these stones and the observed features favour a resorption origin.…”