“OPENING”AND “CLOSING”HISTORY IN EAST QINLING AREA
Yang Weiran (Wuhan College of Geology, Wuhan 430074)
East Qinling lies between North China old land and Yangtze old land. Its tectonic evolution is essentially the history of continuous opening-closing of the two old lands. In the light of opening-closing characteristics, four stages can be divided. 1. Mid-late proterozoic plate subduction-convergence stage. 2. Paleozoic fault orogenic belt formation stage. 3. Early Mesozoic fault block mobilization stage. 4. Late Mesozoic-Cenozoic fault basin development stage.