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Lessons in sailing, science
Superior Telegram (8/16)
A workshop offered by the Great Lakes Sea Grant Network has local educators on a six-day boat trip as part of the Duluth Tall Ships Festival.

NOAA to work with MTU scientists out on Lake Superior
WLUC-TV - Marquette, MI (8/16)
With the help of The National Oceanic Atmospheric Administration or NOAA, Michigan Technological University scientists continue to learn about their surroundings.

Sturgeon hatchery to offer tours in Onaway
WPBN-TV - Traverse City, MI (8/10)
The Michigan Department of Natural Resources is offering tours of the Black River sturgeon hatchery in Onaway. During the free tours, researchers will be available to talk about sturgeon biology, reproductive ecology and this year’s research.

Watch 4 months under Lake Michigan pass by in just 3 minutes
MLive (7/29)
Ever wonder what goes on underneath the surface of Lake Michigan? If so, you're not alone. Scientists wonder, too.

UMD researchers reveal data from wetland studies in the Northland
KQDS-TV - Duluth, MN (7/27)
From Green Bay Wisconsin to Duluth Minnesota, research is being conducted to figure out the current status of our lakes and rivers when it comes to invasive species, and other aquatic trespassers.

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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