To log this
EarthCache you will be required to take material samples from 2
locations on site. Items needed are pre-labeled envelope or
other small container for each sample, dull object to scrape
samples (keys, coin etc.) magnifying glass, and a strong light
source.
The
History
N
41°22.408
W 095°57.228
In 1812 Manuel Lisa, president of the Missouri
Fur Company, established near this spot a trading post to engage
the local Indian tribes and fur trappers in commerce, supplying
necessities and luxuries to both in trade for furs, cattle, horses
and land, and served as a base from which Manuel Lisa acted as a
subagent to neighboring tribes for the federal government. With his
wide trading network, Manuel Lisa had a unique role in relation to
American Indian tribes. He traveled extensively among them to share
agricultural products and build relations, as well as to promote
trade. According to one source, the influence of Manuel Lisa,
exerted from Fort Lisa, was strong enough to hold all
the Missouri
River Indians
firmly in alliance with the American people. Lisa supplied the
Lewis and Clark expedition 8 years prior in their exploration of
this region and himself became the first
U.S.
settler of
Nebraska
by establishing this post
which he ran successfully until his death in 1820 when Joshua
Pilcher succeeded Lisa as president of the fur
company. Fort Lisa was closed in 1823 after Pilcher's Post was
established downriver at what was to become
Bellevue
Nebraska.
The
Geology
N
41°
22.020 W
095°
57.426
To the immediate west of this spot are bluffs
comprised of windblown Loess. East of this spot lies a flood plain
and beyond that the Missouri
River.
Loess
A wind-deposited accumulation composed of silty
material with an open structure and a relatively high cohesion.
Loess is usually deep, fertile soil, rich in organic remains
(especially the shells of snails) and characterized by slender,
vertical tubes that are said to represent stems and roots of plants
buried by sediment. When cut by streams or other agencies, loess
remains standing in cliffs exhibiting a vertical, columnar
structure; this is attributed to the vertical tubes and to the
angularity of the grains and their tendency to interlock. The
uncompacted character of Loess makes it subject to rapid erosion.
Loess grains are angular, with little polishing or rounding,
composed of crystals of quartz, feldspar, mica and other minerals.
Because the grains are angular, loess will often stand in banks for
many years without slumping. This soil has a characteristic called
"vertical cleavage", which makes it easily
excavated.
Flood
Plains
Flood plains are created when the slope of the
stream bed becomes slight and the decreasing velocity deposits
sediments from higher regions. Under these conditions a stream will
often begin to meander and widen the valley by eroding the
outside curve of the stream loops due to a higher velocity current
and depositing on the inside curves where the velocity is lower.
This tends to level out the stream valley. In times of flood, the
rush of water down the whole valley both erodes, when the velocity
is high, and deposits when receding, resulting in further planation
(creation of flat terrain) of the stream's
valley.
Missouri
River
The Missouri
Riverhas
always carried, in suspension, an immense amount of solid matter,
mostly very fine light sand, discoloring the water and justifying
the name of "Big Muddy." The yearly average of solid matter carried
into the Mississippiby this river is estimated at over 500 million
tons. While the Missourihas a greater annual flow of water than
the Mississippiabove its mouth, it is subject to greater
fluctuations. These have affected its navigability in certain
seasons and caused the shoreline to shift, some farms and villages
to disappear, and others to be left far back through deposits of
the soil in front of them. The Missouriis the longest river in the
United
States(2,466
miles). It drains a watershed of approximately 580,000 square miles
as it winds around hills and bluffs, through one of the most
fertile valleys in the world, to its junction with
the Mississippi. Although it was thought for years that no
keelboat could ascend the Missouri, it later became the great highway into the
West.
Logging
Tasks
N 41° 22.020 W
095°
57.426
To log this EarthCache you will be required to
take material samples from 2 locations on site. Items needed
are pre-labeled envelope or other small container for each sample,
dull object to scrape samples (keys, coin etc.) magnifying glass,
and a strong light source.
Remove a minimal amount of Loess from the
hillside exposure (1 tsp) at N 41 22.020 W 095 57.426 and place
into container. Use caution in wet weather as the Loess soil
underfoot is slick and unstable. Cross the road to the east beyond
the walkway and brush away loose material to reach the soil and
sample an equal amount. Recover sampled area with the loose
material. Do not gouge or dig at either site, you will be taking
surface samples only.
Compare the properties of each soil sample:
Appearance, color, texture, reflective qualities, odor. Based on
your observations, describe in an email to the cache owner, the
properties of each sample and what you believe are their origins.
These observations do not need to be done on site.
And
Give your opinion based upon the three features
(bluffs, floodplain, and river) of this area why would Manuel Lisa
choose this area for his trading post/fort?
There are no incorrect answers for this part,
the question is asked to illustrate how each of these resources
could contribute to the success of Manuel Lisa's
business.
Optional
Upload a photo of yourself, an avatar, or your
gps at the historical marker or the Loess exposure.
You will not need to wait for a response to log
the cache online, however, logs not meeting all of the requirements
within a reasonable time frame will be deleted.
References: http://www.answers.com/topic/missouri-river
Wikipedia contributors, "Floodplain," Wikipedia, The Free
Encyclopedia,
http://en.wikipedia.org/w/index.php?title=Floodplain&oldid=220387910
(accessed June 19, 2008).
http://www.answers.com/topic/loess
Wikipedia contributors, "Manuel Lisa," Wikipedia, The Free
Encyclopedia,
http://en.wikipedia.org/w/index.php?title=Manuel_Lisa&oldid=294690049
(accessed June 6, 2009).