Paleomagnetic constraints on the geodynamic history of the major blocks of China from the Permian to the present

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Abstract
Paleomagnetic study of China and its environs has been the center of a major international effort for the last 10 years. In this paper, we critically review all available paleomagnetic poles of Upper Permian to Tertiary age from the main blocks of China with the goal of placing constraints on models of the formation and the subsequent deformation of the region. After selecting “reliable” poles by applying objective criteria, we divide our analysis into first‐order (motions of blocks) and second order (deformation within blocks). For first order analysis, apparent polar wander paths are constructed for the major blocks. We discuss the compatibilities and contradictions between the geological and paleomagnetic records. A sequence of paleogeographic configurations taking into account geological constraints but remaining within paleomagnetic uncertainties is presented. In general, the major blocks were probably in contact throughout the Permian and Triassic, but the Jurassic was the key age during which most of the movement toward China's present configuration took place. Our reconstructions include certain details which are suggested by the paleomagnetic record but whose geological signatures seem to have been hidden by subsequent events. During the Cretaceous, Chinese poles agree with poles from other continents transferred onto Eurasia. At the second order, we observe that for almost each period with sufficient data the paleomagnetic poles are streaked along a small circle centered on the sampling region, indicating that much of China has been affected by small (< 20°) differential rotations. This we interpret as deformation caused in part by the extrusion of the Chinese blocks away from the Indian collision. The complete annotated list of poles is given as an appendix.
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