Basement Tectonics 13 -

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Résumé :
The Thirteenth International Conference on Basement Tectonics was held on the campus of Virginia Polytechnic Institute and State University in Blacksburg, Virginia from June 2 -6, 1997. The oral presentations and discussions over three days covered a wide range of topics, and provided the international audience with a perspective on scientific efforts underway around the world. The conference participants were able to attend two separate field trips: (I) a pre-conference trip guided by Professor Robert Hatcher of the University of Tennessee, Knoxville, examined the Basement rocks in the North Carolina -Tennessee region of the Appalachian Mountains, and (2) a mid-conference field trip guided by A.K. Sinha, convener of the conference, allowed participants to examine the complex rock associations and structures of the> 1000 m.y. old basement rocks in Virginia. Both the field trip guidebooks and abstract volumes were published for the conference. The meeting brought together scientists from more than 14 countries. Their participation, and the fiscal success of the meeting would not have been possible without the support of the Department of Geological Sciences, the College of Arts and Sciences (VPI&SU) and the Basement Tectonics Association. Their support is gratefully acknowledged. As Chairman of the Organizing Committee, I would like to thank Margie Sentelle, Jay Thomas, Peter Welch, and Barry Robinson for the smooth operation of the conference.

Sommaire:
Selected Proceedings Papers.- Geotectonics and Characteristic Features of Fertile and Non-Fertile Younger Granites, Eastern Desert, Egypt.- Structural Associations of the Basement and Sedimentary Cover of the Georgian Part of the Caucasus.- The Eastern Edge of the Rio de la Plata Craton: A History of Tangential Collisions.- New Data and Interpretations for the Precambrian, Midcontinent USA.- Allochthonous Units in the Variscan Belt of NW Iberia: Terranes and Accretionary History.- Early Compression and Late Dextral Transpression Within the Grenvillian Event of the Hudson Highlands, NY, USA.- Crust-Forming Processes: Basement and Basements in the Southern Appalachian Orogen.- Petrogenesis of Pan-African Granitoids, Gabal Hamra Area, Southwestern Sinai, Egypt.- Geology of the Blue River Gneiss, Eastern Arbuckle Mountains, Oklahoma.- Zircon Ages of Basement Orthogneisses from the Northern Segment of the Araguaia Belt, Brazil.- Damodar Graben-A Centre of Contrasting Magmatism in the Eastern Indian Shield Margin.- A New Tectonic Belt in the Baltic Sea Region-Farther Interpretation of the Deep Seismic Results from the Baltic Sea and Babel-B Profiles.- A Geochemical Reconnaissance of the Roseland Anorthosite Complex, Virginia, and Comparisons with Andesine Anorthosites from the Grenville Province, Quebec.- Basement Tectonic Structures Delineated from Aeromagnetic Survey Data South Eastern Desert, Egypt.- Appalachians in the Time Interval Between the Grenville Orogeny and Variscan Collision.- Geodynamics of the Early Precambrian: Evidence for the Baltic Shield.- Lead Isotope Mapping of Crustal Reservoirs Within the Grenville Superterrane: II. Adirondack Massif, New York.- Paleomagnetism of the Boot-Phantom Pluton and the Amalgamation of the Juvenile Domains in thePaleoproterozoic Trans-Hudson Orogen, Canada.- Dengying Formation Gas System of the Sichuan Basin, Southwest China: Model for Precambrian Indigenous Hydrocarbon Accumulation.- Morphology and Isotopic Age of Zircons from Shear-Zones Within Granitoids of the Belomorian Tectonic Zone, Baltic Shield, Russia.