羌塘地块中侏罗世古地磁新结果及其对班公湖-怒江洋演化过程的制约

摘要

To constrain the relationship between the Qiangtang and Lhasa terranes and the evolution of the Bangong-Nujiang Ocean,we carried out a paleomagnetic investigation of the Middle Jurassic limestone of the southern Qiangtang terrane in the Tibetan Plateau.Stepwise thermal demagnetization successfully isolated high-temperature characteristicdirections.The site-mean direction of13sites is Dg=334.7°,Ig=51.2°,kg=27.9,α95=8.0°(in geographic coordinates),and Ds=245.2°,Is=54.1°,ks=113.9,α95=3.9°(in stratigraphic coordinates).