Abstract
Ar-Ar analyses of biotites carried out for the samples collected systematically from the contact aureole revealed the ages older than the host rocks. This old biotite ages are due to that the biotites trapped the excess argon wave happened by the thermal heating. The excess argon waves also happen by the white mica decomposition in the high T metamorphic rocks and by the argon release from white micas during the deformation in the exhumations of the host schists. The author appeals to the audiences for the excess argon wave with reviewing the papers for the waves.
