As the Glacier had an impacted on
the area. By adding their melt water as the Glaciers moved back to
the north. The Cedar River has influenced the area itself. By
changing, it’s course over thousand of the years of flow. Curing
the Cedar Valley as it is Today. .
To the west and South is Hartman
Reserve Nature Center is a 300 acre wooded isle located in the
heart of metropolitan Black Hawk County. Hartman lies in the center
of the Waterloo, Cedar Falls area. It offers many activities and
experiences to all its visitors. Hartman Reserve Nature Center is
an entity of the Black Hawk County Conservation Board. Since our
creation in 1976 Hartman Reserve Nature Center has been designated
as an Iowa Watch able Wildlife Site and an Important Bird Area.
Deer, otter turkeys, pileated woodpeckers, red-shouldered hawks,
foxes, vultures, and bald eagles are some of the wildlife you might
see.
Glaciers have been likened to
mighty rivers of ice. Although they move many times more slowly,
glaciers have equivalent changes in flow rate and often form falls
of fast-moving ice above slow-moving ice pools. Glaciers flow
faster down their centers than at ice margins, and more quickly at
the surface than at the bed.
we have been successful in
observing glacial movement, but only partially successful in
understanding the mechanisms that control it. Some glaciologists
say that ice is a PERFECTLY PLASTIC substance. (That is, brittle
and capable of cracking like a solid, yet deformable and capable of
flowing at other stresses.) (Patterson, 1981). Glaciologists have
defined two distinct types of glacial movement -- deformation of
the ice, and sliding of the glacier upon its rock bed. You can see
where deformation has taken place by observing the wavelike flow
patterns within the ice. Near the equilibrium, line on Visually
Glacier perhaps 5 to 20 percent of the glacier's movement is caused
by ice deformation; 80 to 95 percent of its movement is caused by
sliding of the entire glacier upon its bed (Hodge, 1974). Note the
effects of glacial sliding where the ice has towed rocks that
scratched the bedrock. .
How fast a glacier moves is mostly
dependent on the thickness of the ice, and on the angle of its
surface slope (Patterson, 1981). Glacier speeds vary when changes
are made in this geometry. They respond to excessively high
seasonal snow accumulations by generating bulges of thicker ice
that may move down valley many times faster than the glacier's
normal velocity (Patterson, 1981). We can measure those KINEMATIC
WAVES using instruments to survey the glacier surface. These waves
leave a legacy of severely cracked ice and often advance the
glacier terminus. Kinematics waves may occur on all large glaciers.
At Mount Rainier, their behavior has been studied on Nisqually
Glacier. One of the most complete records of kinematics wave
movement is shown in. When measured during May 1969, at its
equilibrium line, Nisqually Glacier moved about 18 inches per day;
during the preceding November it moved only 8 inches per day
(Hodge, 1974). Glaciologists disagree about exactly how water flows
inside and beneath glaciers. However, they agree that these changes
in speed are likely indicators of maximum and minimum water storage
in cavities within the ice. .
in an e-mail to me: .
1. Tell me the height of these
boulders at it’s tallest point. .
2.Describe to me the surface
texture of the boulders. (Is it rough, smooth, etc.) .
3.Based on what you might know
already, or what I've described in this Earth cache’s write up, how
can one be certain that this boulder is not from this area?
.
and .
4.When you log this cache, please
upload a picture of yourself/team with your GPS clearly visible in
front of the boulder. .
Special Thanks to ED Gruenwald the
director of Hartman Reserve Nature Center for allowing me to place
this earthcache. .