Glaciers and ErosionGlaciers and Erosion• Glacier = Large moving mass of ice and snow

Alpine vs. Continental Glaciers

Ice Sheet During the Last Ice Age

At the end of an ice age, glaciers retreat.

Valley glaciers form a U- Shaped Valley *Unlike a riVer valley!

Main Glacial Features

• Deposits are unsorted

– Glacial Till

– Moraine

• Striations = Rocks may have scratches or a polished side due to abrasion under tremendous weight = glacial grooves

The Great Lakes and Finger Lakes in NY are big examples of striations/glacial grooves.

•Erratics =Erratics = Can be very large and not match bedrock/soil composition

Drumlins

Opposite of a sand dune!

Kettle Lakes

1. Glaciers recede2. A block of ice breaks off the glacier3. Debris from the glacier filled in around the block of ice from the outwash. 4. When the block of ice finally melted, all the debris fell into the hole creating the kettle type basin, which filled with water became a lake.

GLACIAL EROSION IS HOW LONG ISLAND FORMED!!

Glacial Evidence on Long Island