This Earthcache is a look back in time. Try and imagine this
entire area almost completely flat. Where you stand is actually a
hundred or so feet below ground. We're going to fast-forward to
today and Look at the red rocks that dot the landscae in this area.
You will NOT actually have to visit any of the rock formations, but
if you choose to, you can.
There are three different types of rock:
Igneous Rock is formed when a magma
cools underground and crystallizes or when it erupts unto the
surface of the ground, cools and crystallizes. Magma that erupts
onto the surface is called lava. When magma cools slowly
underground the crystals are large enough to see. When it cools
quickly on the surface, the crystals are very small and you would
need a magnifier or a microscope to see them. Sometimes, when the
magma cools very quickly, it forms a kind of black glass that you
cannot see through.
Sedimentary Rock forms from particles,
called sediment, that are worn off other rocks. The particles are
sand, silt, and clay. Sand has the largest particles while clay has
the smallest. If there are a lot of pebbles mixed with the sand, it
is called gravel. The sediment gets turned into rock by being
buried and compacted by pressure from the weight above it. Another
way it becomes rock is from being cemented together by material
that has been dissolved in water. Often, both cementing and
compaction take place together.
Metamorphic Rock is formed by great
heat, or pressure, or both. The pressure can come from being buried
very deep in the earth's crust, or from the huge plates of the
earth's crust pushing against each other. The deeper below the
surface of the earth, the higher the temperature, so deep burial
also means high temperatures. Another way that high temperatures
occur is when magma rises through the earth's upper crust. It is
very hot and bakes the rock through which it moves. Hot liquids or
gases from the magma also can cause chemical changes in the rock
around the magma.
To complete this earthcache, do the following:
- Take a picture of yourself
and/or your GPS Near the sign(Not with the sign in
picture).Optional per new guideline
- Send an email to me with the answers
to the following questions:
- How many tributaries are listed on the sign. There IS MORE
THAN ONE.
- What principal type of rocks comprise this area.
- What specific rock is listed?
- What type of tributary is the Green River in this
area?
- What era and how old are the rocks near the Flaming Gorge
Dam?
- For the Bonus Question: What do you think made the hole in the
Bottom of the sign
Per the new Earthcaching guidelines: If
you are concerned with privacy issues, You don't have to be in the
picture. Please do submit a photo with your GPS in it. Also, IF you
can do a screenshot of your Tracklog that will do.