Bulletin of the Geological Society of Malaysia, Volume 43, Dec. 1999, pp. 631 – 641
Seismological Bureau of Anhui Province, Hefei, P.R. China
Abstract: Within the eastern segment of northern border zone of the Sino-Korean platform, eastern Liaoning province and southwestern Jilin province, eastern China, there are many left-lateral wrench faults trending NE and compression structures trending NW. One of the main wrench faults is the Mishan-Fushun fault zone which is the northern extension of the Tancheng-Lujiang fault zone. It was formed since Indo-Sinian Stage and its large scale left-lateral horizontal movement lasted to the Early-Middle Mesozoic. Thrust and nappe structures are found mainly on southeastern side of the Mishan-Fushun fault zone; their history can be traced back to Caledonian orogeny. In the Early-Middle Mesozoic, the wrench fault zone and the compression structures controlled the tectonic development of this region.
The Mishan-Fushun fault zone left-laterally dislocated the Sino-Korean platform, the Caledonian fold belt and the Variscan fold belt. Distances of separation are about 129-159 km. Compression within the northern border fault zone of the Sino-Korean platform led to intense shortening of the crust by 50.2-75.2%. A model showing the crust subduction is proposed in the paper, which shows basement decoupling and slipping-napping in the platform, A-type subduction along the northern border of the platform and imbrication within the fold region. There are several large molasse basins behind the subduction zone, and large amount of transitional crust-syntectic type granitic rocks in front of the subduction zone.
On the basis of correlating the regional geology and analysing the different scale of structures, the author discusses the genetic relationship between the wrench fault zone and the nappe structures of this region and their tectonics evolution during the period from Indo-Sinian to Early Yenshanian Stages. Activity and earthquakes within the studied area are also studied.