THE GEOLOGY OF THE CASSIAR ASBESTOS CEPCSIT

sy W. N. Prums

CASSIAR 1S LOCATED IN NORTHERN British CoLUMGIA, FIFTY MILES
SOUTH OF THE YUKON BORDER AND 100 MILES FROM Watson LAKE ON THE ALASKA
HickwaY. It 1s A MOGERN COMMUNITY OF MORE THAN 1,100 PEOPLE. HIGH QUALITY
CHRYSOTILE ASDESTOS WITH A LOW IRON CONTENT 1S PRODUCED IN A 2,500 TON PER’

DAY MILL. THE MINE 1S AN OPEN PIT OPERATION AT AN ELEVATION OF 6,000 FEET

tn tHe CassiaR MOUNTAINS.

THE AREA HAS PRODUCED PLACER GOLD since 1872 OUT THE
ASBESTOS ONLY BECAME ECONOMIC tN 1953, CHIEFLY BECAUSE OF THe ALASKA

HIGHWAY.

THE OREDODY OCCURS IN A SILL OF SERPENTINIZED PERIOOTITC
THAT INTRUOES THE WEST LIMD OF A SYNCLINE IN PaALEOzZOIC SEDIMENTARY AND
VOLCANIC ROCKS. IT STRIKES NORTHERLY, DIPS MODERATELY EAST ANO INCREASES
IN SIZC WITH DEPTH. THE LONC-FIDRE ASBESTOS VEINS ARE FISSURE FILLINGS
IN WCLL—FRACTURED MASSIVE SERPCNYINE, CONTROLLED BY A WAItWNOR FOLO IN THE
SILL. : ae :

Tur GENCSIS OF THE ORE 1S ASCRIOCD TO INTENSE FRACTURING

ANO HEAT RESULTING FROM THE INTRUSION OF THE NEARDY CASSIAR CRANITIC

DATHOLITH.