Oceanic crust on the northern margin of Gondwana—evidence from Early Paleozoic ophiolite in central Qiangtang, Qinghai-Tibet Plateau.

It is generally considered that the breakoff of the northern margin of Gondwana took in the Devonian forming the Paleo-Tethys, which continued to evolve till the Late Triassic. Recently, a complete ophiolite association has been found in the Taoxinghu-Guoganjianian area, central Qiangtang, SHRIMP U-Pb zircon dating of cumulate gabbro with geochemical characteristics of MORB yielded ages of 467-431 Ma. This is the first found Early Paleozoic ophiolite in the Longmucuo-Shuanghu suture zone and records the information about the early evolution of oceanic crust on the northern margin of Gondwana. The breakoff of the northern margin of Gondwana probably took place in the Early Paleozoic.