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 Italian alps Dinwoody Glacier. Wind River Range, Wyoming.

GAME OF MASS BALANCE SNOW IN vs WATER/ICE OUT

IDEALIZED MOTION- CROSS SECTION

 = strain rate A = constant related to ice temperature  = basal shear stress (?) n = exponent with an average value of 3 GLEN’S FLOW LAW  gh sin 

TEMPERATURE MATTERS Does cold or warm ice strain more rapidly?

STRESS-STRAIN RESPONSE (WATER) (DEBRIS FLOW)

MASS FLUX - BIRD’S EYE VIEW

VELOCITY DISTRIBUTION - BIRD’S EYE

VELOCITY IN SECTION VIEW WHAT’S GOING ON AT THE BED????

WHAT IS THE TEMPERATU RE AT THE BASE OF THE ICE? - GEOTHERMA L -FRICTION -AMBIENT AIR

WARM BASED ICE sliding along bed

FOX GLACIER, New Zealand

COLD-BASED ICE frozen to bed

DRY VALLEY AREA-- ANTARTICA

COMPARE, WARM VS COLD

U IMPLICATIONS FOR EROSION INTENSITY CLASSIC U- SHAPED VALLEY EROSION REQUIRES WARM BASED ICE, WHY?

PLUCKING ….

PLUCKING IN ACTION

ABRASION -STRIATIONS AND POLISH

ABRASION TAKES TOOLS

“THE DIRT MACHIN E” GLACIERS AS A CONVEYOR BELT FOR ROCK DEBRIS

WHERE DOES ERODED MATERIAL GO? MORAINE FORMATION INDICATES A STILL STAND

MORAINES LATERAL TERMINAL

Frans Joseph Glacier - Tom Lowell

MASSIVE COASTAL MORAINES

MORAINES ARE SCARCE IN INTERIOR NEW ENGLAND -- IMPLIES RAPID, DYNAMIC ICE MARGIN RETREAT (KOTEFF AND PESSL)

OUTWASH PLAINS FROM WATER CARRIED DEBRIS

PRESENT DAY OUTWASH -- MT COOK

SEDIMENT DELIVERY TO ICE MARGINAL LAKES

LAKE SEDIMENTS

TASMAN GLACIER

TILL - NOT WELL WASHED BY WATER BASAL VS MELTOUT SIERRA NEVADA, ALPINE CENTRAL MASS, CONTINENTAL

ESKER

DRUMLIN - STREAMLINED FEATURE

KETTLED TERRAIN

KETTLE FORMING TODAY