Discussion on the Tectonic Setting during Indo China Epoch of the Lazhulong Xijinwulan Yushu Suture Zone, on North Margin of Qiangtang

The north suture zone of Qiangtang landmass exhibits obviously tectonic seguament during Indo China epoch. Its eastern part developed ophiolite system in Yushu area, which indicates a ancient limited ocean basin. As the limited ocean basin extended to the west direction, it first transformed as a intracontinental rift, then it became a continental marginal rift valley. At the same time, the ophiolite association disappeared progressively from the east to the west. And at the western part, the petrotectonic assemblage had changed into the bimodal volcanic rock association.