Discovery of Early Silurian graptolite fossils in the Qimantag Group in thewestern sector of the East Kunlun

The authors discovered an Early Silurian graptolite assemblage of Monoclimacis griestoniensis(Nicol ),Monograptus priodon(Brow),Monograptus sp.,Streeptograptus cf.becki (Barrande)and Torngn-igraptus cf.arcuatus(Borrade)within the lower horizon of turbidites in the original Ordovician Qimantag Group in the Baiganhu area,Qimantag Mountain,western sector of the East Kunlun Mountains.This sug-gests that Early Silurian strata also occur in the Qimantag Group in addition to Ordovician strata.This is the first time that reliable megafossils were discovered in the western East Kunlun,which has great signifi-cance for the study of the stratigraphic division and correlation and tectonic evolution in the area.