A Fault Plane of Unusual Aspect. 



297 



knobs are alike affected. There is no plucking. (6) In places 

 a paste of broken igneous fragments overlies the smoothed and 

 fluted surface. The removal of the brecciated material reveals 

 the familiar grooves beneath. (7) Two slabs pried from the 



Fig. 8. 



Fig. 8. Normal fault, post-dating the major thrust fault which produced 

 the slickensides. 



ledges were found to be striated on both their lower and upper 

 surfaces. (8) Microscopic examination of the rock shows that 

 the surface zone has been modified in texture — the sort of 

 metamorphism resulting from pressure of rock on rock, not of 

 ice on rock. 



