AGE AND SIGNIFICANCE OF VOLCANIC ROCK OF EARLY CRETACEOUS IN THE BAN GE-QIELICUO AREAA IN TIBET

Our research results show that volcanic rock of Qushenla Formation is angular unconformity with Shamuluo Formation(J₃-K₁s),and it is covered in angular unconformity by Jingzhuoshang Formation(K_1-2j),and its age of Rb-Sr radisotope is 126Ma.All evidence above show that volcanic rock of Qushenla Formation is syntectonic volcanic rock.As time is determined for volcanic rock of Qushenla Formation, it should separate out from Dongqiao ophiolite,it will put out new data for going deep into the research of the ophiolite,and it also should provide the evidence for orogenic event of Early Cretaceous in the Bangongcuo-Nujiang combine zone.