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Strategic plan targets invasive species
The Superior Daily Telegram (11/17)
Douglas County’s Land Conservation Committee is forwarding a plan to the county board that takes aim at invasive species.

Mich. Clean Marina Program: Public-private partners work together to improve water quality
Grand Rapids Environmental News Examiner (11/9)
Partners from the public and private sector in Michigan are working together in a voluntary program to improve the quality of the Great Lakes.

Researchers seek funding for wind test site in Lake Michigan
Grand Rapids Environmental News Examiner (11/7)
In a recent article in The Muskegon Chronicle, it was reported that researchers at Grand Valley State University’s Michigan Alternative and Renewable Energy Center (MAREC) cited a lack of year-around data (on wind platform testing) needed by prospective development companies.

COMMENTARY: Senate needs to pass clean energy act to help Michigan
The Grand Rapids Press (10/26)
Senate Majority Leader Harry Reid was absolutely correct with his recent proclamation about the current condition of the Great Lakes State: "The State of Michigan," Reid declared from the Senate Floor, with a copy Time Magazine in his hand, "is in trouble."

First Nation women 'walk the environmental talk'
WeNews (10/23)
Tomorrow's global day of climate activism aims for media and political attention. First Nation women have another way. Since 2003, they've walked the shoreline of a Great Lake or major river, meditating on the needs of an unborn generation.

City making big push for water school
The Business Journal (10/23)
The push is on to convince the University of Wisconsin-Milwaukee that the best location for its new School of Freshwater Sciences is near the university’s existing Great Lakes Water Institute on East Greenfield Avenue.

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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