HR: 1330h
AN: T43C-01    [Abstracts]
TI: Resolving Accelerations of Earth's Tectonic Plates
AU: * Bowin, C
EM: cbowin@whoi.edu
AF: Woods Hole Oceanographic Inst., 266 Woods Hole Road, MS#24, Woods Hole, MA 02543 United States
AU: Kuiper, H
AF: Cooperware, Engelenburg 329 2035 RK Haarlem The Netherlands, Netherlands
AB: The fact that the Pacific Plate has recently been documented (Bowin, 2004) to have had two periods of acceleration during the past 68 million years means that conservation of angular momentum must apply to Plate Tectonics. The angular momentum lost when the Pacific plate shifted (at about 46 my) from underthrusting the North American Plate at Sakahlin to underthrusting the Eurasia and Philippine Plates, was at least in part conserved by a renewal, at about 46 my, of suduction of the Australian Plate beneath the Indonesian arc /trench. These results raise the probability that large roller-type thermal convection cells are NOT active in the Earth, and that spreading centers are passive reaction features. The fact that the plate accelerations, numerically, are about 10-8 times smaller than their velocities explains why plate accelerations have been so elusive. However low these acceleration rates are, they, nevertheless, confirm that it is impulse forces that produce the mountain building observed today and in the geologic record. In this paper we summarize our efforts to improve resolving the acceleration history of the Pacific Plate, and also the acceleration histories of other plates comprising the Earth's surface. Our principal new methodology utilizes filtering the quaternions of Euler pole series, and the recalculation of their stage poles.
UR: http://www.whoi.edu/scc (No.12)
DE: 8102 Continental contractional orogenic belts
DE: 8121 Dynamics, convection currents and mantle plumes
DE: 8149 Planetary tectonics (5475)
DE: 8155 Plate motions--general
DE: 8157 Plate motions--past (3040)
SC: Tectonophysics [T]
MN: 2005 Joint Assembly