2. Formation of
Gneiss
Beginning with the
Precambrian Era, two
billion years ago, the
granite-like rock of
gneiss and schist, also
known to be a
metamorphic rock,
formed the core of this
canyon.
http://tapestry.usgs.gov/ages/precambrian.jpg
Gneiss is a mineral that is
coarse-grained and has
distinct mineral layers. It is a
metamorphic rock that is
affected by heat and
pressure. Schist is another
metamorphic rock that is thin
and has flaky layers of platy
minerals. http://upload.wikimedia.org/wikipedia/commons/4/4e/Augen-gneiss-2.jpg
3. The gneiss and schist that makes up the steep walls of the Black Canyon
formed 1.7 billion by the collision of ancient volcanic island arcs. These arcs
caused the surface of the metamorphic rocks that were exposed to extreme
heat pressure.
http://pubs.usgs.gov/of/2000/ofr-00-0365/subzon.gif
http://static.bbc.co.uk/earthscience/images/ic/640x360/natural_disasters/volca
no.jpg
4. http://img197.imageshack.us/img197/4343/pangea.jpg http://eas.unl.edu/~tfrank/History%20on%20the%20Rocks/Nebraska%20Geology/Cretaceous%2
After Pangaea broke up
the continents were free to
drift apart, eventually after
millions of years the plates
that the continents sit upon
converged, (continental-
continental convergence)
causing an uplift of a
region that results in large
mountain ranges or
plateau in the case of the
Black Canyon. http://www.divediscover.whoi.edu/images/tectonics-collide.jpg
6. The uplifting process formed
the Colorado Plateau 5 million
years ago. This plateau
stretches through parts of
Colorado, New Mexico, Utah
and Arizona. The plateau
occupies 130,000 square miles.
http://pubs.usgs.gov/fs/fs-0145-99/fig1.jpg
http://4.bp.blogspot.com/_u8RzBC9dWv0/SLw3Bkj7YyI/AAAAAAAAAt4/K7jQ6eO6-sY/s400/Dsc00162+Vermillion+Cliffs+b.jpg
7. The rise of this
plateau caused
the rivers that run
through this area
to slowly erode
creating a canyon.
The Gunnison
River began to run
through the land,
and down the slop
of the plateau to
form the Black
Canyon.
http://www.nps.gov/blca/photosmultimedia/upload/blca_innercanyon01a.jpg
Though to create the
canyon it took over two
million years because the
minerals of Gneiss and
Schist are very hard to
erode away.
http://cdn.c.photoshelter.com/img-get/I0000vAF73HzvJwI/s/840/Black-Canyon-Gunnison-6038.jpg
8. The flow of the Gunnison River through the Black Canyon though did not
begin until after the ending of volcanic activity in the West Elk Mountains as
well as the San Juan Mountains.
http://www.cbc.ca/gfx/images/news/promos16x9image/2011/07/06/volcano-cp-00900761-460.jpg
http://farm5.static.flickr.com/4147/5026005786_334de962ae.jpg
http://www.dvorakexpeditions.com/wp-content/flgallery/images/8trgu7xm.jpg
9. Fluvial process, defined as running water (stream and rivers) is the
unchanneled downward movement of surface water as well as water
movement along the bottom of a valley.
http://www.ngu.no/upload/Klima%20og%20milj%C3%B8/Landskapsutvikling/Overflate.jpg
http://www.roadtripamerica.com/routes/2010/black_canyon_ericfoltz-590.jpg
The Black Canyon has been eroded away by the Gunnison river that flows
through the bottom of the valley. The river breaks down the metamorphic
rock and carries it downstream to be deposited elsewhere. Since the river is
rather large erosion is greater than if it where just a stream.
10. The black
canyon forms a
V shape due to
the river and its
erosion.
http://3.bp.blogspot.com/-1b4loAL42Es/UEgVkmjPIEI/AAAAAAAAAQ4/VP6m-MQNPFw/s1600/Gateway+018+(Large).JPG
The stream cuts into the
land because it is freely
flowing down the slope of the
canyon, thus it creates a v-
shape rather than a U-shape
left by a glacier.
http://www.backpack-and-gear.com/image-files/black_canyon_of_the_gunnison_national_park.jpg
