Cochise College        Student Papers in Geology

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Roger Weller, geology instructor

wellerr@cochise.edu
                                 

Mass Wasting
Brian Mitchell

Physical Geology

Fall 2006 

Mass Wasting In Southern Arizona

                                                                                                            mass wasting in Carr Canyon

     Mass wasting is defined as the down slope movement of earth materials due to gravity.  This is an important part of the erosion process since large materials are moved from a high elevation to a lower elevation.   Large mountain ranges and steep peaks make Arizona an exiting place to view mass wasting. 

                                                                   large boulders in the Huachuca Mountains

                Mass wasting can occur slowly over time, or happen suddenly.  Slow mass wasting consists of creep and slump.  Forms of fast mass wasting include rock falls and rolling rocks.  Arizona’s arid climate creates a good environment for most forms of mass wasting. 

                                                                   mass wasting in Catalina Mountains

              Slope failure and sediment flow are common causes of mass wasting.  Slope failure is the collapsing of a slope that causes debris to descend by sliding, rolling, falling or slumping.  Sediment flow causes debris to flow downhill due to water or air. 

                                                                                         mass wasting in Santa Rita Mountains

                The main factors that influence a change in mass wasting include changing in the slope angle; weakening of material from weathering; increase in water saturation; vegetation change; and overloading.  All these factors are common here in Arizona. 

                                                                                            eroded cliff in Carr Canyon

References:  (web sites used for research)

1)      http://geology.about.com/od/nutshells/a/landslidenuts.htm

2)      http://www.geology.wisc.edu/courses/g112/mass_wasting.html

3)      http://seis.natsci.csulb.edu/bperry/mass%20Wasting/Introduction_to_mass_wasting.htm

4)      http://en.wikipedia.org/wiki/Mass_wasting

5)      http://landslides.usgs.gov/index.php

6)      http://wapi.isu.edu/envgeo/EG4_mass_wasting/EG_module_4.htm

7)      http://serc.carleton.edu/NAGTWorkshop/visualization/collections/mass_wasting.html

All photos used in presentation were taken from my personal collection.