Mesozoic through Cenozoic
What was happening back in the
Western Cordillera?
All the stuff we already talked about
plus….
Hawaii!
Pangaea breaks up
• Red beds, basalts and normal faults on East Coast
• How do we know what other continent North
America broke away from? What is your
evidence?
• fit of continents, fossils, paleomagnetic stripes on
Atlantic floor, climate bands, paleomag on
continent, glacial till etc., ancient mtns and rocks
that run across the continent boundary
What’s happening in Europe and Asia?
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Look at the maps
Watch the animations
Alps?
India?
Mediterranean (maps)
Alps/ Himalaya
• As Africa and India move northward, they collide
with Europe and Asia
• India forces SE Asia and China to the east as it
pushes northward
• Creates SE Asian peninsulas, Sea of Japan and
Tibetan Plateau as well as Himalayas
• Tethys closes and dries up, leaving a basin where
the new Mediterranean sea floor forms. The
Med fills as the Gibraltar end erodes through to
the Atlantic
What’s happening to Central America?
• Animation
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Cenozoic Glaciation
Extent of glaciation in N. America and Europe
Effect on world climate belts
Evidence for glaciation?
Glacial till – unsorted, angular
U-shaped valleys, horns, cirques, aretes
Glacial striations & polish
Moraines – piles of debris left as glacier melts
Erratics – large boulder carried by a glacier and
dropped as it melted
• Dropstones – boulder dropped when iceberg
melts
Consequences of glaciation
• Glacial lakes and pluvial lakes
Kettle lakes
in Minnesota
Pluvial lakes:
formed from
increased
rainfall south
of the
glaciers
Consequences of glaciation
• Glacial lakes and pluvial lakes
• Glacial deposits
– Moraines and till
– Glacial outwash – rock dust carried by meltwater
– Loess (wind-blown rock dust)
Consequences of glaciation
• Glacial lakes and pluvial lakes
• Glacial deposits
• Glacial landscapes
Consequences of glaciation
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Glacial lakes and pluvial lakes
Glacial deposits
Glacial landscapes
Large continental shelves
Consequences of glaciation
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Glacial lakes and pluvial lakes
Glacial deposits and landscapes
Large continental shelves
Exposed Canadian shield – all younger rocks
scraped off