A three-day meeting, convened by R. Hall (University College London), G. J. Nichols (Royal Holloway and Bedford New College) and C. Rangin (Paris), was held at the Geological Society in London on 18–20 April 1990. The aim was to draw together workers from a variety of earth science disciplines who are studying or exploring the boundaries of the Australian and Eurasian Plates with the Pacific Ocean, and other scientists who are looking for modern analogues of older orogenic belts. Of the 124 participants, 58 came from Australia, China, France, Germany, Indonesia, Italy, Japan, Malaysia, Netherlands, Singapore, Taiwan, USA and USSR and 39 from industry. There were some 60 oral and poster presentations.
The first day focused on the Australian margin between Indonesia and New Guinea. M. G. Audley-Charles (UCL) discussed some practical problems of active orogenic belts; despite the youth (Pliocene and younger) of collison zones in such areas as Timor, there are still considerable difficulties in identifying sutures. Several speakers drew attention to the changing expression of arc–continent collision along the strike of the collision zone. A. J. Barber (RHBNC) described the structure of the Australia-Banda Arc collision zone where seismic records show mud diapirism in the 400 km wide forearc accretionary complex south of Sumba; further west on Timor the equivalent zone narrows to less than 150 km, and Australian margin sedimentary and basement rocks are stacked in a duplex. R. A. Harris (West Virginia) suggested that past disagreements in interpretation may be a consequence of a failure