MICHIGAN BEACHES

MICHIGAN BEACHES

ventifacts

• Rocks smoothed from wind erosion• Angular• Smooth on 1-2 sides

Formation of Dunes

• Sand supply– glaciers (MI)

• prevailing wind– westerly

• blockade– moraines (MI)

Michigan Dunes

• Form on the EAST side of Of the Great Lakes

DUNE FORMATION

Pinery

Ludington

Sleeping Bear

Sleeping Bear Sand Dunes

• Perched dune• On top of a moraine

The Sleeping Bear

• Long ago, in the land that is today Wisconsin, Mother Bear and her two cubs were driven into Lake Michigan by a raging forest fire. The cubs swam strongly but the distance and the water proved too much for them. They fell further and further behind and ultimately slipped beneath the waves. When Mother Bear reached the Michigan shore, she climbed to the top of a bluff and peered back across the water, searching vainly for her cubs. The Great Spirit saw her and took pity on her plight. He raised North and South Manitou Islands to mark the place where her cubs vanished and laid a slumber upon Mother Bear.-Ojibway Indian Legend

1995 slide

Silver Lake

SILVER LAKE

Dune Erosion

• Due to– lack of

plants/trees–human activity–bad weather

Dune erosion

• Which direction will this dune move?

• How to stabilize this dune?

windwardleeward

wind

You can help protect the dunes by: staying on paths, not

littering, by leaving plants and wildlife in

place

BARCHAN DUNES (overhead view)

Dune sand

• Abrasion–Creates “frosted

grains”– angular

• mainly quartz–hard–Plentiful

Dune sand :angular pieces of…

Quartz87%

Feldspar10%

Magnatite3%

Sagutuck, MI

Ogden Dunes. INLake MI 1986

Lake Erie House

Loess

• Wind blown dust• Yellowish

WAVE EROSION

CAPE HATTERAS LIGHTHOUSE

Lake Michigan

Rip-rap

Lake MichiganLakeshore Drive

1 YEAR AFTER $20 MILL. BEACH NOURISHMENT

• Upham Beach, FL

Save my beach!

• http://www.as.uky.edu/academics/departments_programs/EarthEnvironmentalSciences/EarthEnvironmentalSciences/Educational%20Materials/Documents/elearning/module14swf.swf