Foto's

Water seems to have had the most impact basically because our planet has lots of it and it is always on the move. Many people cannot understand how water can have such a profound impact considering that the Canyon is basically located in a desert.
Because the soil in the Grand Canyon is baked by the sun it tends to become very hard and cannot absorb water when the rains to come. When it does rain the water tends to come down in torrents which only adds to the problem.
The plants that grow in the Grand Canyon tend to have very shallow root systems so that they can grab as much water as possible on those rare occasions when it does rain. Unfortunately these root systems do nothing to deter erosion by holding the soil in place.

Now you've got lots of water, no place for it to go, but down to the Colorado River, and nothing holding the soil and rock in place. The result is frequently a flash flood roaring down a side canyon that can move boulders the size of automobiles, buses and even small houses.
This mass that moves down a side canyon during a flash flood is more like a fast flowing concrete than water and it can be very dangerous.
The Colorado's spring floods used to carry away all of the debris that was deposited in the main channel by the flash floods, but todays mediocre flow rates have a tough time doing the job. It still gets done to some extent, it just takes a lot longer. In the process of moving the rocks and sediment down the river to the Pacific Ocean the bed of the river is scoured by all of this fast moving debris which slowly eats away at the banks and bed of the river. This causes the river to widen and cut down deeper into the lower rock layers. Another cause for the slowing of the erosive force of the Colorado River is the fact that it is now trying to cut through harder granites and schists found at the bottom of the Canyon instead of the softer limestones, sandstones and shales near the top. This rock takes a lot longer to erode and a slower moving river means it takes even longer…
(read more at http://www.bobspixels.com/kaibab.org/geology/gc_geol.htm)


P.S.
Inside a chopper shot image


Model - NIKON D700
Artist - ruisc_pt
ExposureTime - 1/125 seconds
FNumber - 7.10
ExposureProgram - Aperture priority
ISOSpeedRatings - 200
DateTimeOriginal - 2011:04:17
MeteringMode - Multi-segment
LightSource - Fine weather
FocalLength - 28.00 mm
DigitalZoomRatio - 1 x
FocalLengthIn35mmFilm - 28 mm
ISO Setting - 200
Image Quality - RAW


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