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CONTINENTAL ICE SHEET - GREENLAND. ALPINE ICE- VALLEY GLACIER(S). GLACIER BAY, ALASKA. ALL GLACIERS HAVE TWO ZONES ACCUMULATION = + MASS ABLATION = - MASS. “Firn Line” = Equilibrium Line. Dinwoody Glacier. Wind River Range, Wyoming. Italian alps.
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ALL GLACIERS HAVE TWO ZONESACCUMULATION = + MASSABLATION = - MASS
“Firn Line” = Equilibrium Line Dinwoody Glacier. Wind River Range, Wyoming. Italian alps
GLEN’S FLOW LAW e= strain rateA = constant related to ice temperature t= basal shear stress (?)n = exponent with an average value of 3 rgh sin a
TEMPERATURE MATTERS Does cold or warm ice strain more rapidly?
STRESS-STRAIN RESPONSE (DEBRIS FLOW) (WATER)
WHAT’S GOING ON AT THE BED???? VELOCITY IN SECTION VIEW
WHAT IS THE TEMPERATURE AT THE BASE OF THE ICE?-GEOTHERMAL-FRICTION-AMBIENT AIR
EROSION REQUIRES WARM BASED ICE, WHY? CLASSIC U-SHAPED VALLEY U IMPLICATIONS FOR EROSION INTENSITY
“THE DIRT MACHINE” GLACIERS AS A CONVEYOR BELT FOR ROCK DEBRIS
WHERE DOES ERODED MATERIAL GO? MORAINE FORMATIONINDICATES A STILL STAND
MORAINES LATERAL TERMINAL LATERAL
MORAINES ARE SCARCE IN INTERIOR NEW ENGLAND -- IMPLIES RAPID, DYNAMIC ICE MARGIN RETREAT (KOTEFF AND PESSL)
TILL - NOT WELL WASHED BY WATERBASAL VS MELTOUT SIERRA NEVADA, ALPINE CENTRAL MASS, CONTINENTAL