Location: Toronto Convention Centre, Toronto, Canada
Web: http://www.jointassembly2009.ca/welcome_english.html
Includes the following sessions:
Session GA08: Frontiers in Precambrian Geodynamics
Convenors: Phil McCausland (pmccausl@uwo.ca), Richard Ernst (richard.ernst@ernstgeosciences.com), Wouter Bleeker (wbleeker@nrcan.gc.ca), Lauri Pesonen (lauri.pesonen@helsinki.fi)
The Precambrian Earth is increasingly being seen as a planet that is recognizably Earthlike, but one in which sometimes extreme circumstances prevailed. There is therefore great opportunity to understand fundamental physical aspects of the Earth’s geodynamic processes through investigating Precambrian events. This session calls for contributions on the Precambrian record of Earth’s paleogeodynamic evolution obtained through paleomagnetism, magmatic events, sedimentology, geochronology, geochemistry and isotope geochemistry as well as insights derived from theory and modeling. A central focus of this session is Earth's paleogeography through the Precambrian, as the ultimate record and ground truth against which to test our understanding of first-order geodynamic processes such as true polar wander (TPW) and supercontinental assembly and dispersal.
This session is convened in honour of the many Precambrian contributions of Henry Halls (U of Toronto), both as a researcher and as a mentor.
Session GA11: The Iapetus Plume Event and Ediacaran Palaeogeography
Convenors: Phil McCausland (pmccausl@uwo.ca), Henry Halls (henry.halls@utoronto.ca), Michael Higgins (michael_higgins@ugac.ca)
The Ediacaran Period, from ~615 to 543 Ma was a time of profound change for the Earth. It appears to have been a time of rapidly growing complexity in metazoan life and of extreme climates. A major tool for unravelling the paleogeographic context for these events should be paleomagnetism, yet it seems unusually difficult to resolve continental configurations during the Ediacaran. Paleomagnetic results available thus far imply apparent motions for some continents that are too rapid to be accomplished by plate tectonics, leading to proposals for large-scale True Polar Wander (TPW) during this period. The Iapetus Plume in eastern Laurentia has been invoked as a possible driver for TPW and also as a pinning point argument against TPW. This session brings together paleomagnetists, geochronologists, tectonicists and petrologists to focus on the Iapetus plume event, the enigmatic Laurentian paleomagnetic results obtained from Ediacaran units and the wider problem of Ediacaran paleogeography. Papers are solicited on any related aspect within the stated time frame, but special emphasis will be placed on understanding the timing, geochemistry and geodynamic features of the Iapetus plume that spawned the Grenville dyke swarm, the Sept Iles intrusive suite, and other alkali and kimberlitic units.
Session V07: Intraplate Volcanic Fields: From Source to Eruption and Techniques for Identifying Patterns of Behaviour
Convenors: Mandie Hintz (arl6@buffalo.edu), Sara Hanson-Hedgecock (sedjat@earthlink.net)
Continental intraplate volcanic fields are characterized by a wide array of eruptive styles and products that are widely distributed across the continents in a variety of tectonic regimes. These volcanic fields occur in virtually all tectonic environments, from extensional (Black Rock Volcanic Field, Utah, USA) to compressional (Michoacán-Guanajuato Volcanic Field, Mexico) and strike-slip (San Quintín Volcanic Field, Baja, Mexico). A field may span from several hundred km2 to more than several thousand km2 and may include anywhere from several volcanic vents to hundreds. This session is dedicated to increasing the fundamental understanding of the patterns of behavior in intraplate volcanic fields through field-based geologic, geophysical, and geochemical investigations. Also of interest are the development of analogue and mathematical models of magmatic, tectonic, and eruption processes, as well as the application of statistics and pattern recognition techniques to volcanic data processing. We hope that the contributions made to this session will aid in our understanding of intraplate source regions and augment our ability to forecast eruptive behavior to mitigate hazards.