TECTONIC EVOLUTION OF THE DONGSHAN TERRANE, FUJIAN PROVINCE, CHINA

Many isolated metamorphic complexes in the coastal region of Fujian Province 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 assemblage, were metamorphosed to high greenschist facies and low amphibolite facies during Late Triassic to Middle Jurassic time. At the same time, the Dongshan terrane amalgamated with the Changchun seamount, and a composite terrane, the Min-Tai terrane, was formed. The Min-Tai terrane represented a microcontinent at the juncture of the paleo-Pacific and Tethys oceans. It migrated northward as a part of the subducting Kula plate until it collided with the southeast Bank of the Late Jurassic-Early Cretaceous Zhejiang-Fujian volcanic are during the late Early Cretaceous. During the collision, multiple stage ductile shearing and southeastward thrusting took place, and NW-SE compressive brittle fracture structures were formed. A dismembered ophiolite suite, the Quanzhou, was emplaced tectonically on the northwest boundary of the Dongshan terrane. The Min-Tai composite terrane fills a gap in the superterrane from Sikhote Alin to Borneo suggested by Mizutani et al. (1986).