HR: 14:40h
AN: T13E-05    [Abstracts]
TI: Baja transfer by partial coupling with the Pacific plate
AU: * Plattner, C
EM: plattner@geophysik.uni-muenchen.de
AF: Dept. of Earth and Environmental Sciences, Section Geophysics, Ludwig-Maximilians University, Theresienstrasse 41, Munich, 80333, Germany
AU: Malservisi, R
EM: roccom@lmu.de
AF: Dept. of Earth and Environmental Sciences, Section Geophysics, Ludwig-Maximilians University, Theresienstrasse 41, Munich, 80333, Germany
AU: Govers, R
EM: govers@geo.uu.nl
AF: Faculty of Earth Sciences Utrecht University, Budapestlaan 4, Utrecht, 3508 TA, Netherlands
AU: Iaffaldano, G
EM: iaffaldano@eps.harvard.edu
AF: Dept. of Earth and Planetary Sciences Harvard University, 20 Oxford Street, Cambrigde, MA 02138, United States
AB: The Baja California (BAJA) microplate was ruptured from the North American (NAM) plate ~ 12 Ma ago and since then translated with the Pacific (PAC) plate. The microplates' transport mechanism has been explained by partial coupling with the PAC plate. According to this theory, the young oceanic lithosphere from the Farallon-Pacific spreading center approaching North America was too buoyant to be subducted. Therefore a zone of increased lithospheric coupling developed between the partially subducted Farallon slabs and the overlying NAM margin. In consequence both, the subduction and the seafloor spreading slowed down and ceased. With the development of this coupling region west of BAJA the main PAC-NAM plate boundary jumped into the NAM continent, east of BAJA. After a phase of distributed extension in the the Protogulf region the new plate boundary localized along the Gulf of California. We use a numerical modeling technique to test the dynamic conditions of BAJA transport as seen from present-day and from geologic plate motion studies. Using the kinematic data we test the necessary coupling forces for BAJA transport, as well as, geometrical constraints along the PAC-BAJA coupling zone. Evaluating the transport conditions at different stages of the plate boundary evolution we want to learn about necessary pre-conditions for the BAJA transfer, in particular along the Gulf of California.
DE: 8106 Continental margins: transform
DE: 8150 Plate boundary: general (3040)
DE: 8155 Plate motions: general (3040)
DE: 9350 North America
SC: Tectonophysics [T]
MN: 2008 Fall Meeting