10.

HAVE TO SOME EXTENT BEEN CONTORTED AND LOGALLY TEND YO CONFORH TO THE
SHAPE OF THE BULGE. NEVERTHELESS, THE NORTH END OF THE SERPENTINE
TRANSECTS THE BEODING AT A SMALL ANGLE. THIS HAS RESULTED IN SOME
SHEARING ALONG THE CONTACTS AND IN NUMEROUS SMALL ADJUSTMENTS,

ESPECIALLY ALONG BEDDING PLANES.

WHEREVER THE FOOTWALL OF THE SERPENTINE 1S IN CONTACT WITH
ARGILLACEOUS ROCKS, A ZONE OF SHEARING ABOUT TEN FEET WIDE IS EVIDENT.
IN THIS ZONE, THE SERPENTINES HAVE BEEN DARKENED BY THE INCLUSION OF
ARGILLACEOUS MATERIAL, THE ARGILLITES HAVE SEEN ALTERED TO GRAPHITIC
SCHISTS, A LITTLE CALCAREOUS MATERIAL. HAS BEEN INTRODUCED AND

LOCALLY, GOUGE AND BRECCIA ZONES HAVE BEEN FORMED.

ALONG THE HANGINGWALL, DARK BLOCKY SERPENTINE 1S IN
CONTACT WITH A NARROW BAND OF ALTERATION» THIS 1S A CREAM—COLOURED
TREMOLITE-ZOISITE HORNFELS. THE DEGREE OF CONTACT METAMORPHISM,
HOWEVER, HAS NOT BEEN AS GREAT AS WOULD BE EXPECTED FROM A HIGH=
TEMPERATURE INTRUSION, WHICH HAS LED TO SPECULATION THAT THE
SERPENTINE MAY HAVE BEEN INJECTED IN A LOW-TEMPERATURE SEMI~PLASTIC

STATE

THERE 1S A VERY PROMINENT SET OF JOINTS IN BOTH THE
FOOTWALL AND HANGINGWALL ROCKS, STRIKING A FEW DEGREES NORTH OR
SOUTH OF EAST ANDO DIPPING STEEPLY NORTH. THIS IS PART OF A REGIONAL
PATTERN OF TENSION FRACTURES AT RIGHT ANGLES TO THe CASSIAR BATHOLI THe
SHEARS OF SMALL O!SPLACEMENT, PARALLELING THE JOINT SYSTEM, ARE
COMMON. AT THE POINT WHERE THE SERPENTINE BULGES AND CHANGES STRIKE
AT THE SOUTH END OF THE OREBODY, A ZONE OF CLOSELY SPACED SHEARING,

STRIKING ABOUT SOUTH 60 DEGREES EAST, CUTS BOTH THE SERPENTINE AND

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