The
Ancient Moraines: Valparaiso, Tinley, and Lake Boarder
During the Pleistocene period Northern Indiana experienced
a few glaciation periods. These glaciations were Wisconsinan, Illinoian,
Kansan, and Nebreskan, but we only have evidence of pre-Illinoian, Illinoian,
and Wisconsin. These glaciation time periods each lasted thousands of years;
during their life spams each glacier would advance and retreat, and this
movement destroyed any evidence of the previous movement. “Ice retreaded from
Indiana 13,600 years ago. Postglacial processes of deposition and erosion then began to modify the glacial
landscape, resulting in the sediments and features that make up the landscapes
we see today.”(Indiana Geological Survey p.2)
Near the
end of the Pleistocene Ice Age many advances and retreats happened. The last of
the advances happened between 15,200 to 2,400 years ago that was the Crown Point phase.
During this time most of the sediments coming from the Lake Michigan lobe were pushed into
hills that formed Valparaiso Moraine; later the re-advancement of the glacier
built Tinley Moraine and Lake Border Moraine. Two of the last Moraines created which
you might have heard of are the Blue Island Ridge and Hobart Island (the low ridge at about 56th and Broadway in Merrillville) ( Schoon p.22).
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The
ancient shorelines: Glenwood, Calumet, and Tolleston
In 1897, Frank Leverett proposed the names for the three
ancient shorelines as Glenwood, Calumet, and Tolleston. He also proposed the
name Lake Chicago which was not followed through in the future. The ancient
shorelines were created by the supply of clay, sand, pebbles, and by the strong
winds of the windy city. (Schoon p.26-27)
The Glenwood Shoreline
The Glenwood Shoreline was the first phase of that occurred
between 14,000 – 12,200 years ago. The elevation of this magnificent shoreline
was 640 feet above sea level. Scientist predict that these shorelines were
developed in the area which are today Dyer and Schererville.The best remaining dune is south of U.S. 30 at Castlewood Drive in Dyer (Schoon p. 28). Also it is the
only shoreline whos one side is a moraine and the other side is lake bottom land.
(Schoon p.28-30)
The Calumet Shoreline
The Calumet Shoreline was the second shoreline to occur,
and its elevation stood at 620 feet above sea level. The development of this
shoreline was somewhat close to where the Glenwood Shoreline use to be. The
shoreline was named after the little Calumet River. Also the Calumet Shoreline
has a much coastline than the Glenwood Shoreline.(Schoon p. 32-35). The shore line can be seen if you drive on Ridge road in Munster (Schoon p. 33).
The High/Low Tolleston Shoreline
The High Tolleston Shoreline developed around 4,700
years ago,and the Lower Tolleston Shoreline was developed 3,800 years ago.
The lower shoreline was created when the lake level dropped to its current
level. The elevation stood at 603 feet above sea level. The shoreline is
named after the village of Tolleston after it was so prominent to the village.
Today that village is part of the city Gary. (Schoon p. 37-38). The Shoreline can be easily seen east of Michigan Avenue in the Roseland are of Chicago ( between 100th and 127th Streets) (Schoon p.36).
Here we
visited Lowell, Indiana where we found some boulders that were dropped off by a
glacier all the way from Ontario, Canada.
Boulder found in Lowell, Indiana.
This is one Route 41 going south; in the picture you
see the black soil. This soil is very fertile soil due to the glacial
deposits. Kankakee Outwash Plain carried melt waters away from glaciers.
These waters eroded valleys, and carried tons of sand and mud. “The Kankakee
Outwash Plain is the result of this large-scale deposition of sand. It extends
across seven Indiana counties” ( Schoon pg. 24). Later 87 percent of the area
became farm land (Schoon pg. 24).
U.S. 41 in Lowell, Indiana
This is right before 231; this is where the
Valparaiso and Tinley moraines separate.
U.S. 41 in Lowell, Indiana
Most of you know Cedar Lake this lake was
created by glacier retreat. There were tiny rivers that were under the glacier;
these rivers were made by friction, and friction gives of heat and creates tiny
rivers under the glacier. When the glacier retreated it melted into the caved
in ground and made the lake.
Cedar Lake at Cedar Lake, Indiana.
Work Cited
Schoon, Kenneth J.
Calumet Beginnings: Ancient Shorelines and Settlements at the South End of Lake
Michigan. Bloomington: Indiana UP, 2003.
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