Date

Session Announcement and Call for Papers
Intraplate Earthquakes Know No Boundaries
American Geophysical Union (AGU) Fall Meeting
10-14 December 2007
San Francisco, California

Abstract Submission Deadline: 6 September 2007

For further information, please go to:
http://www.agu.org/meetings/fm07/?content=search&show=detail&sessid=485


Papers are invited for Session T33: "Intraplate Earthquakes Know No
Boundaries" being convened at the American Geophysical Union (AGU) Fall
Meeting on 10-14 December 2007 in San Francisco, California.

Session Description:
The problem of intraplate earthquakes is a geological puzzle that has no
clear physical mechanism or scientific paradigm. Recent controversies on
the activity or non-activity of present source zones from GPS
measurements, the possible migration of seismicity in continental
interiors, and efforts to understand the physical state of the crust
within continents away from plate boundaries through EarthScope and
other large-scale experiments makes a review of the tectonic mechanisms
for intraplate events timely.

Session conveners hope to discuss competing models of driving mechanisms
for intraplate earthquakes and stimulate new thinking on this
long-standing problem. Multiple orogenic and thermal events in Earth's
history have produced a fertile environment for earthquake nucleation
within the continents. Simple plate kinematics combined with first-order
differences between continental and oceanic lithospheric rheologies
suggest that continental edges and plate boundaries are the most likely
places for earthquake generation in the crust. However, intraplate
earthquakes are far from the well-springs of warm, pliable plate
boundaries that strain continuously to take up plate motion. If plates
behave rigidly, the standard elastic/plastic rheological model predicts
that no stress is stored in the viscoelastic reservoirs of intraplate
lithosphere so that the elastic portions of the upper crust, lower
crust, and upper mantle must support local, regional, and plate-wide
stress fields. What are these stress fields and what causes
time-dependent changes in the strength of the intraplate lithosphere? Do
time-dependent changes in the state of driving stresses produce
intraplate seismicity? Is there geological, geophysical,
hydrogeophysical, or geochemical evidence for spatial or temporal
migration of seismicity in continental interiors? Papers aimed at
exploring mechanisms for intraplate seismicity and mid-continent
tectonism for North America are encouraged, although presentations
related to global intraplate events and processes are also welcome.

Conveners:
Charles A. Langston
University of Memphis
E-mail: clangstn [at] memphis.edu

Lorraine Wolf
Auburn University
E-mail: wolflor [at] auburn.edu

Further information and abstract submission procedures are available at:
http://www.agu.org/meetings/fm07/