Dear Colleagues,

As we are sure you are all aware of by now, the next Geological Society of America meeting will be held in Minneapolis, MN (9-12 Oct 2011).

 With the deadline for abstract submission still a few days away (July 26^th, 2011), and the fact that many of us seem to wait until the last minute to submit abstracts, we’d like to draw your attention to three complimentary sessions that focus on different aspects of lithospheric deformation.

 Please consider contributing an abstract to one of the sessions listed below, and please feel free to distribute this information broadly. You can submit your abstract online at http://gsa.confex.com/gsa/2011AM/cfp.epl . 

T21. Constraints on Strain Rates, Stresses, and Deformation Processes During Shear Zone Localization at Different Lithospheric Levels

GSA Structural Geology and Tectonics Division; GSA Geophysics Division

Co-convenors: Julie Newman, David Kohlstedt, Basil Tikoff, Seth C. Kruckenberg

This session will provide a venue for new data (field-based, experimental, geophysical, microstructural, etc.) that constrain rock rheology during shear zone localization at different structural levels within the lithosphere. Experimental rock deformation, field-based investigations, microstructural analyses, geophysical techniques, and advances in numerical modeling have documented a range of conditions that contribute to shear zone localization, including compositional and phase variations, chemical reactions and rheological heterogeneities. This session seeks broad contributions that provide insights on shear zone localization within different structural levels of the lithosphere, as well as variations in strain rates, stresses, and deformation processes across shear zones, and how these factors interrelate. 

T22. Deformation of the Lithosphere: Field Observations, Experimental Investigations, and Numerical Studies

GSA Structural Geology and Tectonics Division; GSA Geophysics Division

Co-convenors: Patrice Rey, Eric Goergen, Seth C. Kruckenberg

   Understanding finite strain resulting from polyphase deformation, long-term progressive deformation, and deformation involving both volume forces and plate boundary forces, remains a key challenge for structural geologists and tectonicists.  Experimental deformation and computational tectonics complement field-based investigation by exploring stress, strain, and strain rate through space and time, and the formation and evolution of complex structures at multiple scales and levels in the lithosphere.

   This session offers a broad platform for field, experimental and numerical studies on the deformation of the Earth's Lithosphere (continental and oceanic).  Discussion will focus on studies linking field geology to experimental deformation and/or numerical modeling, from micro- to plate-scale structures.  Contributions that address coeval extensional and contractional deformation, complex stress and strain patterns, and/or coeval deformation of rheologically distinct layers are particularly encouraged.

   NB: Co-sponsored by the GSA’s Structural Geology and Tectonics Division and GSA’s  Geophysics Division, this session will host the 2011 GSA Keynote Lecturer.  This session links to GSA short course 513: Gale/Underworld Framework Tutorial. This open source numerical framework opens new avenues for 2D and 3D computational tectonics.

Invited speakers include: Louis Moresi (Monash University, Australia), Whitney Behr (University of Southern California), and David Boutelier (University of Toronto, now at Monash University).

 T23. Multidisciplinary Studies of Fault System Deformation

GSA Structural Geology and Tectonics Division; GSA Geophysics Division

Co-convenors: Eric Horsman, Sarah Titus

The session will feature multidisciplinary studies of fault system deformation and architecture over all spatial and temporal scales.  We encourage submissions from authors utilizing geology, geophysics, geodesy, geomorphology, modeling, etc. to study these systems.

Invited speakers include: J. Ramon Arrowsmith (Arizona State Univ.), Alastair McClymont (Univ. of Calgary), and Harold Tobin (Univ. of Wisconsin).