Metamorphic studies: research in progress

Abstract

Report of a meeting of the Metamorphic Studies Group held at Burlington House, 16 March 1983. The meeting was organized by Dr M. Brown. A Metamorphic Studies Group Meeting on ‘Metamorphic studies: research in progress’ together with the second Annual General Meeting of the Group were held on 16 March 1983; approximately 65 members of the Group participated in the meeting. A total of 13 papers was presented, covering a wide range of interests in metamorphic geology and including a mixture of old faces and new contributors; it was disappointing that only four of the papers were given by current research students, although it remains the policy of the Group to encourage research students to contribute to its meetings. The morning session, chaired by Professor Bernard Leake, was opened by Brown, who presented an account of the metamorphic history preserved within cordierite-bearing pelitic gneisses from Timor in eastern Indonesia. The rocks, which form part of the Mutis Complex, are allochthonous, having been located in SE Asia during Mesozoic time and having been emplaced onto Australian continental rise deposits by thrusting during the mid-Pliocene collision between the Banda Arcs, now separated from SE Asia by the Banda Sea marginal basin, and the Australian continental margin. Estimated metamorphic conditions resulting from decompression under high temperatures evolved from T > 750°C and P ≃ 10 kbar through T ≃ 700°C and P ≃ 5 kbar at P H 2 <O < 0.5 P total to T = 550-600°C and P ≃ 2 kbar. This uplift path