The complex and segmented Taiwan orogenic belt is located on the convergent boundary between the Eurasian Plate and the Philippine Sea Plate. The southern part of the orogen is in the early stages of collision, while the northern part is in the last stage due to the oblique convergence, with the changing of tectonic setting from compression to extension. Previous studies of sandbox modeling in Taiwan are more concentrated on the effect of arc-continent collision and basement high but only a few noted the effect of the opening of Okinawa Trough. Our 3D experiments aim to better understand the structure and tectonic evolution of the northern Taiwan-Ryukyu area by adding a sandpaper machine composed of motor, bearing, and sandpaper that could move freely during the experiment to simulate the opening of the Okinawa Trough. By analyzing experimental images and Particle Image Velocimetry (PIV), and comparing it with seismic profiles, GPS, and paleomagnetic data, the results show that clockwise rotation of northern Taiwan is mainly related to the oblique convergence. The opposite movement of the Philippine Sea Plate and the different movement patterns between north and south of Ilan plain are mainly related to the opening of Okinawa Trough. The morphology of Ryukyu area is mainly controlled by the shape of the subducted Philippine Sea Plate, which also causes strata fold. The Okinawa Trough opens from east to west causing the clockwise rotation of the Ryukyu arc, which also leads the west to be narrower than the east.
|Translated title of the contribution||Oblique Convergence and Back-arc Extension in Northern Taiwan-Ryukyu Area: Insights from Sandbox Modeling|
|Original language||Chinese (Traditional)|
|Number of pages||7|
|Journal||Acta Geoscientica Sinica|
|State||Published - Sep 2022|