TECTONIC EVOLUTION OF THE DONGSHAN TERRANE, FUJIAN PROVINCE, CHINA

Many isolated metamorphic complexes in the coastal region of Fujian Pr ovince are juxtaposed with the Mesozoic volcanic rocks in the interior mountainous region of Fujian. The metamorphic rock belts comprise the Dongshan terrane. The protoliths, an early Paleozoic volcanic are ass emblage, were metamorphosed to high greenschist facies and low amphibo lite facies during Late Triassic to Middle Jurassic time. At the same time, the Dongshan terrane amalgamated with the Changchun seamount, an d a composite terrane, the Min-Tai terrane, was formed. The Min-Tai te rrane represented a microcontinent at the juncture of the paleo-Pacifi c and Tethys oceans. It migrated northward as a part of the subducting Kula plate until it collided with the southeast Bank of the Late Jura ssic-Early Cretaceous Zhejiang-Fujian volcanic are during the late Ear ly Cretaceous. During the collision, multiple stage ductile shearing a nd southeastward thrusting took place, and NW-SE compressive brittle f racture structures were formed. A dismembered ophiolite suite, the Qua nzhou, was emplaced tectonically on the northwest boundary of the Dong shan terrane. The Min-Tai composite terrane fills a gap in the superte rrane from Sikhote Alin to Borneo suggested by Mizutani et al. (1986).