The collision of the Sino-Korean and Yangtze blocks to form a signific
ant part of China is recorded in the Qinling, Tongbai, and Dabie Mount
ains. Radiometric ages of the ultrahigh-pressure metamorphic rocks in
the South Qinling orogenic belt suggest that subduction and collision
took place during the Triassic Period. Our new Ar-40/Ar-39 geochronolo
gy of units in the North Qinling orogenic belt confirms that high-grad
e metamorphism and deformation took place also during the Silurian-Dev
onian and Carboniferous Periods. These results Imply that the amalgama
tion of eastern China was a multistage process extending over at least
200 m.y.