Palaeoproterozoic arc magnatism and collision in Liaodong Peninsula (north-east China).

Michel Faure (1) , Wei Lin (2, 3) , Patrick Monié (2) , Olivier Bruguier (4)

1 ISTO - Institut des Sciences de la Terre d'Orléans
2 Department of Earth and Planetary Sciences [Kobe]
3 IGG - Institute of Geology and Geophysics [Beijing]
4 LDL - Laboratoire Dynamique de la Lithosphère

In the north-eastern part of the North China Block, a afic magmatic belt consisting of mafic–ultramafic rocks and marine sedimentary rocks crops out between the northern Archean Anshan Block and a southern Palaeoproterozoic Block. 40Ar ⁄ 39Ar amphibole ages around 1.9 Ga from gabbros, and trace element analyses of gabbros, pyroxenite and shale show that these rocks formed along a Palaeoproterozoic active continental margin. The mafic magmatic belt is interpreted as an arc developed above a south-directed subduction zone, which was subsequently overthrust to the north upon the Anshan Archean Block. This study provides a new example agreeing with increasing evidence supporting plate mobility and thrust tectonics during the Palaeoproterozoic. These new insights must be considered with regard to the formation of the North China Block by magmatic accretion and tectonic collision.

Domains: Tectonics

Michel Faure, Wei Lin, Patrick Monié, Olivier Bruguier. Palaeoproterozoic arc magnatism and collision in Liaodong Peninsula (north-east China).. Terra Nova, 2004, 16, pp.75-80. ⟨10.1111/j.1365-3121.2004.00533.x⟩. ⟨hal-00068285⟩