Shorelines, Glaciers, and Changing Sea Levels

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Shorelines, Glaciers, and Changing Sea Levels
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Observe the topography of the northeastern U.S.
Area pockmarked with small lakes
Lake Superior
Lake Huron
Lake Michigan
Lake Ontario
Lake Erie
Long Island
Delaware Bay
Superior Michigan Huron Erie Ontario The
Great Lakes
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Appalachian Mountains
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Smaller features
Smooth areas in Dakotas and Minnesota
Other smooth areas
Lake Superior
Lake Huron
Lake Michigan
Lake Ontario
Lake Erie
Long Island
Delaware Bay
Ridges in smooth areas
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Prairie Coteau between
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The Canadian Shield
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The Michigan Basin
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Geomorphology

• Canadian Shield, Michigan Basin, Appalachian
  Mountains are old features
• The other (smooth areas, ridges, troughs, bays,
  etc.) are much younger
• Due to glacial processes and/or changes in sea
  level
• Refer to the newer features as geomorphology

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Observe the topography of the western Great Lakes
area
Lake Superior
Smooth troughs
Troughs are areas where glacial ice advanced
Lake Michigan
Curved ridges
Curved ridges are recessional or terminal
moraines
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Many lakes formed on shield as ice retreated even
more
Great Lakes formed as glaciers retreated northward
s
Moraines
Limit of Pleistocene Glaciation
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Observe the topography of the northeastern U.S.
glacial trough
Old mountains
Rising sea levels flooded inland areas
glacial sediments
Rising sea levels flooded inland areas
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Dynamic shorelines
Energy from Wind Waves Tides Gravity Currents
Wave erosion In Yorkshire
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Ocean waves
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Shoreline features

• Deposition
• Erosion

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Changing shorelines

• Change in land elevation (tectonics)
• Change in sea level (more/less ice)

Estuary
Mouth of the River Exe
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Submergent and emergent coastlines
Sea level rises Or land drops
Sea level falls Or land rises
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Categories of glaciers

• Mountain glaciers
• Cirque glaciers

Grand Teton Glacier
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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers

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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps

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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers

Ellesmere Island
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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers
• Continental glaciers
• Ice sheets

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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers
• Continental glaciers
• Ice sheets
• Ice shelves

Larsen Ice Shelf
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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers
• Continental glaciers
• Ice sheets
• Ice shelves
• Ice caps

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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers
• Continental glaciers
• Ice sheets
• Ice shelves
• Ice caps
• Ice fields

British Columbia
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Categories of glaciers

• Mountain glaciers
• Cirque glaciers
• Valley glaciers
• Mountain ice caps
• Piedmont glaciers
• Continental glaciers
• Ice sheets
• Ice shelves
• Ice caps
• Ice fields
• Outlet glaciers

Ice ages
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Physics of glaciers
Gravity moves glacial ice downhill Melting
causes a glacier to retreat
Valley glacier in the Alps
Valley glacier Baffin Island