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University of Windsor invasive species research centre closes
CBC News (5/27)
The Canadian Aquatic Invasive Species, based at the University of Windsor, is closing because it's run out of federal funding.

Stockbridge HS invention to monitor Great Lakes pest
Lansing State Journal (5/27)
In Michigan, a team of Stockbridge High School students has spent the past year designing an underwater camera to keep tabs on the state’s fight against invasive sea lampreys. Next week their invention will get its first real test.

'Once in a lifetime ' experience: Lighthouse keeper on Lake Superior
CBC News (5/19)
A group is hiring two students to serve as lighthouse keepers this summer on Porphyry Island, about 40 kilometers east of Thunder Bay, Ont.

Superior students set sail for hands-on learning about St. Louis River, Lake Superior
Wisconsin Public Radio (5/16)
Close to 1,500 students from northern Minnesota and Wisconsin set sail for a day on St. Louis River to learn about the Great Lakes, as part of the week-long St. Louis River Quest.

Tree group aims to ‘ReLeaf’ Michigan
WKAR - East Lansing, MI (5/10)
An Ann Arbor-based organization has been planting trees all over Michigan since 1988. ReLeaf Michigan helps property owners learn about trees and how to plant them, citing their numerous benefits.

Coldwater bacteria threatens Great Lakes salmon
Charlevoix Courier (5/3)
A new study shows a bacterial disease that sickens fish whether raised in captivity or in the wild is imperiling popular salmon species in the Great Lakes Basin.

TEACH Calendar of Events
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
TEACH Shoreline Geology

2 | Let's go to the beach!

Frankfort, Michigan. Click for larger image. How are beaches created?
The most common type of shoreline in the Great Lakes region is the sand beach. Sand is deposited on beaches when the waves from the lake move it up from the lake bottom to the shoreline, and the sandy shorelines are ever changing. Littoral transport carries sedimentary material both parallel to the shore (longshore transport) and perpendicular to the shore (on-offshore transport). The wind can also transport sand, carrying both large and small grains and depositing them either up or downshore. Humans can also transport sand. For example, non-contaminated sand dredged from lake bottoms is sometimes added to a beach to increase its size or to replace beach sand that has eroded.

Sand sculpture. Click for larger image. Why are beaches important?
Because the land and water are constantly meeting one another, many different life forms inhabit a beach, such as algae and other microfauna. Therefore, beaches are rich feeding grounds for migratory shorebirds. The beach also collects driftwood and other debris that a variety of beetles, spiders, and shorebirds like to feed upon. Shoals, sandbars, and spits often protect marshes and other wetlands from excessive wave and wind action. Spits, such as Long Point on Lake Erie and Oak Point on Lake Superior, may provide a habitat for plant and animal communities. And, of course, beaches are great places for us to go swimming!

What is sand made of?
Quartz. Sand consists of rocks, crystals, and sea shells that are eroded over a long period of time by wind, water, and ice. The composition of sand can change greatly from beach to beach. For example, the black sand beaches of Hawaii are composed of volcanic ash and rocks, while the white beaches of the Caribbean consist of sea shells. The tan-colored beaches around the Great Lakes area are made up mostly of grains of quartz.

Ancient beaches
Although no longer located on a body of water, beach ridges are common in the Great Lakes region. These ancient ridges formed the seashores of the proglacial lakes, and were left behind as the lakes' levels dropped to their current elevations. The Ridges Sanctuary in Door County, Wis., contains 16 beach ridge formations. Another ancient beach ridge formation runs from the present day Maumee River, past Toledo, Ohio, and into southern Michigan.

See also GLIN's Beaches page, and BeachWatch, Recipe for a Beach


Graphics: beach at Frankfort, Michigan; sand sculpture; and, a sample of quartz

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