Abstract:

Melt lineation is a special linear structural element of highgrade metamorphic rocks, which is composed of long lens or rodlike aggregates of melted leucoveins distributed along Xaxis direction of strain ellipsoid. Melt lineation developed in ductile deformation zones of deep structural levels of crust and may indicate the moving direction as the mineral stretching lineation does. Melt lineation is controlled by deformation, metamorphism and partial melting in an extensional tectonic environment. The main mechanism of melt lineation is extensional deformation which led to partial melting of highgrade metamorphic rock. Melt lineation keeps a lot of rock rheological information of deep crust, which is of great scientific significance for probing into rock rheological mechanism of deep crust and the formation and evolution of early crust.

Key words: Daqingshan, highgrade metamorphic rock, melt lineation；partial melting