8

A number of smaller workshops, meetings, discussions, and field trips, all funded by other agencies, were held by IGCP 406 participants during 1998. These are mentioned where relevant in the Progress by National Groups, and many are listed in a later section of this report.

Progress by National Groups
Australia:
Five people participated this year in the IGCP 406 program: C. Burrow, K. Trinajstic, R. Parkes, S. Turner, and G. Young. Two others, J. Long and Z. Johanson, continued studies of relevance to IGCP 406. Co-operative work on the Silurian-Lower Devonian includes studies by S. Turner (Queensland Museum), C.J. Burrow (UQ, Australia) and J.M.J. Vergoossen (U Groningen, Netherlands) on Late Silurian (Burrow et al. in press) and early-mid Devonian samples collected by R. Thorsteinsson (Canada) from Prince of Wales, Cornwallis, Young and Dundas islands: microvertebrates comprise thelodonts, heterostracans, anaspids, acanthodians, placoderms, chondrichthyans, sarcopterygians. Their results and those of other participants continue to show strong links in the Early Devonian with faunas elsewhere in the Canadian and Russian Arctic, and further links with those of the Baltic (former Baltica), Nevada (Cordillera terrane), and even eastern Australia (Eastern Gondwana).
Ross Parkes (MUCEP) is helping to prepare and sort the 1995 (IGCP 328) field trip samples collected by Z. Johanson in the Canadian Arctic, and is comparing material with samples from the Lower Devonian of Nevada (M. Murphy coll.).
S. Turner continues work on Lower Silurian (Aeronian) microfossils from Wisconsin and Michigan, central U.S.A. and Early Silurian material of Arctic and Maritime Canada - the latter in conjunction with Dr G. Nowlan (Canada). S.T. and C. Burrow continue work on thelodont, anaspid and acanthodian material from the Late Silurian of Somerset Island, Arctic Canada, a project with Dr J. Savelle (Canada) who collected the original samples (Turner 1999). At IGCP 406, Jurmala, in September 1999, S.T gave presentations on Silurian microvertebrates (especially new thelodonts) from the Canadian Arctic, maritime Canada and the Michigan Basin, USA, and on new Russian Arctic lungfish specimens collected by ST during the IGCP 328:SDS field trip to Timan in 1994; comparison was made with other microtoothplates of lungfish being found in Late Devonian Frasnian and Famennian deposits in Russia and Australia.
Gavin Young (ANU) was invited to conduct research at the Museum of Natural History, Paris, where he was able to work in co-operation with Dr D. Goujet (France) and with Dr E. Kurik (Estonia) on the taxonomy and biogeography of placoderms from arctic Russia and the South Urals. A paper by GCY and EK on a new brachythoracid arthrodire from the Emsian of the Urals is to be submitted to Journal of Vertebrate Paleontology. Work on the Upper Devonian includes completion of a PhD thesis by Kate Trinajstic (UWA) on the Gneudna Formation (Carnarvon Basin) microfauna, which contains analysis of many fish taxa and includes squamation mapping of key Late Devonian palaeoniscoids known worldwide (Trinajstic 1999a, b). S. Turner was able to visit the Institute of Geology in Warsaw to continue work with Dr M. Ginter (Poland) on early Famennian microvertebrates from Melville Island, Arctic Canada; we completed a description of a new phoebodont shark and an analysis of the recovery of this group of pelagic sharks following the Kellwasser events (Ginter & Turner 1999). Also, preparation of calcareous rocks collected in Timan led to the discovery of juvenile lungfish toothplates from the Izhma Formation (Frasnian-Famennian boundary; Turner 1999a). Co-operative work on the samples from Timan is agreed with Dr Alexander Ivanov (St Petersburg University, Russia).
Z. Johanson and J. Long are (separately) collaborating with P. Ahlberg (UK) on rhizodont fossils from Australia, as well as on studies of Australian placoderms and associated forms that have Circum-Arctic relatives. Canada:
S. Cumbaa continues his collaborations with H.-P. Schultze (Germany) on Devonian vertebrates from the Anderson River area, Northwest Territories.
M.Sc. students B. Hunda and K. Soehn, and professors. B. Chatterton and M. Wilson continued work on materials from the Avalanche Lake sections (Ordovician -Silurian) of the Mackenzie Mountains, Northwest Territories. Hunda's thesis (supervisor: Chatterton) was successfully defended in September 1999; it concerns Ordovician/Silurian trilobites of the AV sections. Soehn (supervisor: Wilson) continues his thesis and related work on Silurian heterostracans and vertebrate biostratigraphy. The paper by Soehn, Wilson, Märss, and Hanke on vertebrate biostratigraphy of the Avalanche Lake sections was accepted for publication by Courier Forschungsinstitut Senckenbergin connection with the special volume of IGCP 328 results. Microfossil samples from Llandovery parts of the section were being dissolved and analysed by P. Männik and T. Märss in Estonia.