Dear all, I wonder if anyone can enlighten me?
What happens when a fracture tip (specifically a joint) intersects with
a active pressure solution cleavage domain? i.e. is it possible to
have a syn-cleavage joint? I have read of syn-cleavage joints &
the classic semi-brittle shear zone tension gashes usually show an
expression on cleavage.(however, this is not always the best of evidnce).
However, if the crack tip is propagating along under Griffiths theory
then hits an active domain where depending on which model you want to
use either the particles are undergoing rotation or dissolution the
crack tip seems more likely to abut the structure & produce the broad
terminations visible in the classic semi-brittle shear zones which are
inferred as syn-cleavage i.e. in the Welsh Uk Variscan. Has anyone
any comments or thoughts on the problem? At the moment i'm not convinced
John G. Rogers
Department of Geology
University College, Cork
Cork
Ireland
|