Weathering and Mass Wasting

          Many people who visit Arizona assume that the Colorado River is the main reason for the beautiful formation of the Grand Canyon.  Even though, the Colorado River does play an important role, there are other factors behind the Grand Canyon's design. 

Beautiful scenery of the Grand Canyon!

          Weathering, which is the process of breaking down rocks in place, is a big factor for the Grand Canyon. Because of faulting, the Grand Canyon begins to break down creating joints in rocks. These joints are spaced cracks and fractures that are very sensitive to pressure. Then weathering breaks down these weak spots into smaller pieces. A specific example of physical weathering is pressure of roots.  Plant roots can grow into cracks causing the rocks to expand and eventually to break.

Several trees and rocks have fallen from the canyon due to Pressure of Root Weathering.

Different ways rocks are broken.  Taken from Professor Allen's power point.

As you can see, there are major cracks and fractures in the rocks.

         As these rocks break and collapse, they fall or slide down to the river due to gravity. This then triggers a new process called Mass Wasting, which is the downslope movement of angular slope materials. Since these rocks are now displaced at the bottom of the canyon, the Colorado River begins to push everything is its way. The Grand Canyon is wide because of Mass Wasting and the Colorado River just unclogs the mess.  The Colorado River is like Drano down a toilet!

Process of weathering and mass wasting. Taken from Professor Allen's powerpoint.

          Since Mass Wasting moves the materials down the canyon, all that remains are slopes. These slopes are very beneficial to our lives because they are sources for ground water, which can be extracted for drinking water. But too much removal of water from the ground (Ground Subsidence) can cause compaction in the land.

The slopes are sources for ground water. Taken from Professor Allen's power point.

The ground level has gone down due to Ground Subsidence. Taken from Professor Allen's Power point.

Works Cited:
http://www.google.com/imgres?imgurl=http://www.zastavki.com/pictures/1600x1200/2009/Nature_Mountains_Grand_Canyon_018928_.jpg&imgrefurl=http://www.zastavki.com/eng/Nature/Mountains/wallpaper-18928-2.htm&usg=__AbUwIyvRYwTwTmfjboThbFYec2I=&h=1200&w=1600&sz=703&hl=en&start=60&sig2=xMOdrrZLKPofBD1OVXw-Sw&zoom=1&tbnid=yFTOwQLEcrJ34M:&tbnh=135&tbnw=172&ei=k_tvTenaOIWosAOhu73NCw&prev=/images%3Fq%3Dgrand%2Bcanyon%2Bwallpaper%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1C1CHFX_enUS398US398%26biw%3D1280%26bih%3D909%26tbs%3Disch:10,1400&um=1&itbs=1&iact=hc&vpx=310&vpy=283&dur=164&hovh=194&hovw=259&tx=181&ty=92&oei=LPtvTZ3lDIbCsAPv7NzSCw&page=3&ndsp=30&ved=1t:429,r:1,s:60&biw=1280&bih=909

http://www.youtube.com/watch?v=lN0cZg_9XeM

http://www.youtube.com/watch?v=XdcGqPdHN44

http://www.google.com/imgres?imgurl=http://www.silverspurtours.com/gfx/lake-powell-river-bend.jpg&imgrefurl=http://www.silverspurtours.com/air-jeep-river-float.php&usg=__SFKq_4wlH1EaPfDOhi4fV9XfGEo=&h=265&w=400&sz=28&hl=en&start=41&sig2=TBxbajLFfK2WdqLLtHH9hw&zoom=1&tbnid=kq416j2WKQ6y3M:&tbnh=167&tbnw=229&ei=ZgFwTfjyF4u-sQPvhfGtDw&prev=/images%3Fq%3Dgrand%2Bcanyon%2Briver%26um%3D1%26hl%3Den%26rlz%3D1C1CHFX_enUS398US398%26biw%3D1280%26bih%3D866%26tbs%3Disch:10,1500&um=1&itbs=1&iact=rc&dur=287&oei=PAFwTczhHIu4sQORqInECw&page=3&ndsp=20&ved=1t:429,r:14,s:41&tx=141&ty=60&biw=1280&bih=866

http://fast.ucdenver.edu/case/1202/Battle/Destroy/Wx/Weathering/DiagWhichCorrect.jpg

http://fast.ucdenver.edu/case/1202/Battle/Destroy/MassWasting/slidetypes.jpg

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiWUL0xmQ2qwUFy7QZ-ZTqRGGEUDQpj49EtEH6zZCnQh1kAuTxZrBm3hRTcX51Pfl0lqBt84L63PMEEKrv6WIcTPGDTN9FS4kyxQ5eUOlM0NHziVd0qGe7BbdYs4EsbdrdvLmc3OAAW5ta2/s1600-h/grand-canyon-sunset-4.jpg

http://fast.ucdenver.edu/case/1202/Battle/Destroy/Hydrology/AZFissures1.GIF