Mackinac Island

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Mackinac Island
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Weathering

• Mackinac Island was formed as the glaciers of
  the last ice age began to melt around 13,000 BC.
  The bedrock strata that underlie the island are
  much older, dating to Late Silurian and Early
  Devonian time, about 400 to 420 million years
  ago. Subsurface deposits of halite (rock salt)
  dissolved, allowing the collapse of overlying
  limestones these once-broken but now solidified
  rocks comprise the Mackinac Breccia.

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Weathering

• As the Great Lakes assumed their present
  levels, Mackinac Island took on its current
  size.4 The steep cliffs were one of the primary
  reasons for the British army's choice of the
  island for a fortification their decision
  differed from that of the French army, which had
  built Fort Michilimackinac about 1715 near
  present-day Mackinaw City. The limestone
  formations are still part of the island's appeal.
  However, tourists are attracted by the natural
  beauty rather than the strategic value. One of
  the most popular geologic formations is Arch
  Rock, a natural limestone arch, 146 feet (45 m)
  above the ground.

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Weathering

• During an intermediate period of low water
  between these two high-water stages, the Straits
  of Mackinac shrank to a narrow gorge which
  discharged its water into Lake Huron through
  Mackinac Falls, located just east of Mackinac
  Island. At least three previous lake levels are
  known, two of them higher than the present shore
  Algonquin level lakeshores date to about 13,000
  years ago, and the Nipissing level shorelines
  formed 4,000 to 6,000 years ago. Other popular
  geologic formations include Devil's Kitchen,
  Skull Cave, and Sugar Loaf. The melting glaciers
  formed the Great Lakes, and the receding
  lakewaters eroded the limestone bedrock, forming
  the island's steep cliffs and rock formations.

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Erosion

• With the onslaught of attention to global
  climate change, it is becoming nearly impossible
  to go through a day without witnessing some sort
  of media coverage on the debate over our
  responsibility to be better stewards of our
  planets limited natural resources. Whether you
  agree or not with the urgency of actively
  managing our environment and its resources, it
  is a topic that is reaching fever pitch in public
  dialogue, media focus and government regulation.
  It is a movement that is undeniable not only in
  the United States but in countries across the
  globe and it shows no signs of slowing or
  reversing.

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Erosion

• A Sobering Thought Across the country,
  deforestation, civil, commercial, residential
  development and construction, bridge and road
  building, road reconstruction, maintenance and
  use, as well as industry growth and use, cause
  massive amounts of water runoff and erosion. This
  runoff carries silt, chemicals, phosphates,
  nitrates, fertilizers and other impurities into
  our water sheds which in turn empty into our
  lakes, streams and rivers that eventually lead to
  our water supply. Water runoff and erosion upsets
  the delicate balance supporting the natural
  filtering of run off water. The impact on the
  environment has become so severe there is a
  distinct possibility that in some areas of the
  nation we are reaching a condition that is
  non-reversible.

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Erosion

• Industry Over the past 7 years the growth
  of the erosion control industry has been
  unprecedented. It is becoming one of the fastest
  growing industries in the American economy today.
  Shore Sox having started research, development
  and testing 8 years ago in 2000, is strategically
  positioned to be a leader in the industry during
  its most aggressive period of growth. Working
  within government regulations and the permitting
  process, where installed, ShoreSox has already
  become an accepted solution the for natural
  erosion control. In fact as of the date of this
  writing, ShoreSox has never been refused a permit
  by local governing bodies.

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Soil

• Lake waters eroded the Limestone bedrock
  forming the islands steep cliffs and rock
  formations. The melting glaciers formed the Great
  Lakes, and the receding lakewaters eroded the
  limestone bedrock, forming the island's steep
  cliffs and rock formations. At least three
  previous lake levels are known, two of them
  higher than the present shore Algonquin level
  lakeshores date to about 13,000 years ago, and
  the Nipissing level shorelines formed 4,000 to
  6,000 years ago

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Soil

• During an intermediate period of low water
  between these two high-water stages, the Straits
  of Mackinac shrank to a narrow gorge which
  discharged its water into Lake Huron through
  Mackinac Falls, located just east of Mackinac
  Island. There was rock salt and it dissolved the
  limestone.

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Resources

• Google Images
• Wikipedia