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Glaciers

Glaciers. LOUIS AGASSIZ IS KNOWN FOR THE IDEA THAT GLACIERS ONCE COVERED MANY PARTS OF THE WORLD. BIRTH OF A GLACIER. BORN IN AREAS WHERE MORE SNOW FALLS THAN MELTS EACH YEAR.   SNOW LINE – THE LOWEST LEVEL THAT PERMANENT SNOWS REACH IN SUMMER HIGHEST NEAR THE EQUATOR.

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Glaciers

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  1. Glaciers

  2. LOUIS AGASSIZ IS KNOWN FOR THE IDEA THAT GLACIERS ONCE COVERED MANY PARTS OF THE WORLD.

  3. BIRTH OF A GLACIER BORN IN AREAS WHERE MORE SNOW FALLS THAN MELTS EACH YEAR   SNOW LINE – THE LOWEST LEVEL THAT PERMANENT SNOWS REACH IN SUMMER HIGHEST NEAR THE EQUATOR B  FIRN IS GRANULAR ICE MATERIAL FORMED IN SNOW FIELDS FROM FRESHLY FALLEN SNOW BECOMING COMPRESSED AND RECRYSTALLIZING THE LOWER LAYERS BECOME ICE AND BEGIN FLOWING DOWNWARD OR OUTWARD BECAUSE OF OVERLYING PRESSURE.

  4. VALLEY GALCIER (ALSO KNOWN AS ALPINE) OCCUR WHERE MOUNTAINS STRETCH ABOVE THE SNOW LINE

  5. CONTINENTAL GLACIERS (ALSO CALLED ICE SHEETS) FORM IN POLAR AREAS WHERE THE SNOW LINE IS CLOSE TO SEA LEVEL AND WIDE AREAS ARE ABOVE THE SNOW LINE

  6. GLACIER MOVEMENT THE OVERLYING WEIGHT OF SNOW AND ICE CAUSES GRAINS OF ICE TO PARTIALLY MELT AND REFREEZE. AS THIS HAPPENS ICE GRAINS SLIP PAST EACH OTHER AND MOVE DOWNHILL GLACIERS MOVE MORE RAPIDLY AT THE SURFACE THAN AT THE BASE AND FASTER AT THE CENTER THAN AT THE SIDES. FRICTION WITH THE VALLEY WALLS SLOW THE FLOW CREVASSES ARE CRACKS ACROSS THE WIDTH OF THE GLACIER THAT FORM WHEN GLACIERS MOVE OVER STEEP SLOPES

  7. ICE FRONT IS THE END OF A GLACIER WHERE THE ICE MELTS AS FAST AS IT MOVES THE ICE FRONT IS STATIONARY AS LONG AS THE RATE OF MOVEMENT AND MELTING ARE EQUAL A GLACIER RECEDES WHEN IT MELTS FASTER THAN NORMAL A GLACIER RECEDES WHEN IT MELTS FASTER THAN NORMAL

  8. GLACIERS PICK UP LOOSE ROCK AS THEY MOVE MORAINE IS A GLACIAL DEPOSIT OF UNSORTED ROCK MATERIAL GROUND MORAINE – CARRIED ALONG THE BOTTOM LATERAL MORAINE – LONG LINES OF ROCK PIECES ALONG THE VALLEY SIDES END MORAINE – AS THE ICE MELTS THE GLACIER’S MOTION BRINGS FORWARD ROCK PIECES. THEY MAY GROW LARGE

  9. ROCK FLOUR IS A MIXTURE OF FINE SAND AND SILT FORMED BY THE CRUSHING OF ROCK UNDER A GLACIER. (GLACIAL MILK) PIECES OF ROCK ARE DRAGGED BY GLACIERS FINE SAND ACTS AS SANDPAPER AND POLISH THE BEDROCK LARGER SEDIMENTS LEAVE LONG PARALLEL SCRATCHES CALLED STRIATIONS ** STRIATIONS SHOW THE DIRECTION OF MOVEMENT**

  10. GLACIAL TROUGH ARE FORMED WHEN A GLACIER CARVE OUT A VALLEY FORMING A U-SHAPED VALLEY VALLEY GLACIERS LEAVE SHARP MOUNTAIN TOPS WHILE CONTINENTAL GLACIERS LEAVE ROUNDED TOPS

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