关键词: 波罗的和西伯利亚板块, 古地磁, 运动学原则, 视极移曲线, 纬向漂移速率, 旋转速率

Abstract:

       Paleomagnetism is one of the most effective quantitative methods for examining ancient plate tectonic evolution and
paleogeographic reconstructions. Based on data from the Global Paleomagnetic Database (GPMDB 4.6) and previously published
paleomagnetic data for the Baltic and Siberian plates, a reanalysis and filtering of Baltica and Siberia Paleozoic paleomagnetic
data has been performed in accordance with internationally accepted basic selection criteria (Van der Voo, 1990) determining
the reliability of paleomagnetic data. From this, a reconstruction of the apparent polar wander paths (APWP) and paleogeographic
positions of the Baltic and Siberian plates has been made by using the GMAP software. In addition, further analysis has been
made by comparing the structural evolution and kinematic characteristics. In conclusion, the following is understood for these two
plates during the Paleozoic. Three convergence events took place during the Late Ordovician (~450 Ma), Early Carboniferous (~360
Ma), and Late Permian (~255 Ma), and the processes of plate convergence follow Newtonian kinematic principles in general.
What needs to be stressed is that under the continental plates is the asthenosphere mantle with an extremely high viscosity, so the
Newtonian kinematic principles cannot be obeyed under non-ideal conditions. Three processes of plate convergence have three
different kinematic phenomena. During the late Ordovician (~450 Ma), both Baltica and Siberia drifted northward and converged
gradually. Baltica with higher latitudinal velocity converted its kinetic energy into Siberia with lower latitudinal velocity. Duringthe Early Carboniferous (~360 Ma), Baltica and Siberia moved towards each other and converged. The latitudinal drift direction
of Siberia changed from the south to the north while the latitudinal velocity of Baltica decreased and became toward the south
gradually. During the Late Permian (~255 Ma), Baltica and Siberia drifted towards each other and converged again. Finally, their
kinetic energy canceled out each other, so both latitudinal velocities became zero.

Key words: Baltica, Siberia, paleomagnetism, kinematic principles, apparent polar wander path, latitudinal drift-rate, angular
rotation