Please respond to both POST1 and POST2 in at least 200 words.

Required

• Chapter 5 Weathering, Erosion, and Sedimentary Rocks (Sections 5.1 & 5.2 only) in An introduction to geology. Salt Lake Community College. Open Educational Resource
• Chapter 10 Mass Wasting in An introduction to geology. Salt Lake Community College. Open Educational Resource
• Chapter 13 Deserts in An introduction to geology. Salt Lake Community College. Open Educational Resource
• Chapter 14 Glaciers in An introduction to geology. Salt Lake Community College. Open Educational Resource

Recommended

• Iverson, R. M., George, D. L., Allstadt, K., Reid, M. E., Collins, B. D., Vallance, J. W., …, & Baum, R. L. (2015). Landslide mobility and hazards: Implications of the 2014 Oso disaster. Earth and Planetary Science Letters, 412, 197-208.
• National Park Service. (2019, September 11). Mass wasting. Retrieved from https://www.nps.gov/subjects/erosion/mass-wasting.htm
• Omosanya, K. O., Harishidayat, D., Marheni L., Johansen, S. E., Felix, M., & Abrahamson, P. (2017). Recurrent mass-wasting in the Sorvestsnaget Basin Southwestern Barents Sea: A test of multiple hypotheses. Marine Geology, 376(2016), 175-193. doi:gor/10.1016/j.margeo.2016.03.003

Using your text and the library or internet resources, research one ofthe many varieties of mass wasting. Explain how it works, what type ofmaterial is involved, and that type of movement. In which regions mightwe find this type of mass wasting? Provide a real-life example of anevent of this type. Once again, make sure that you come up with anexample that hasn’t been discussed already.

POST1:

Masswasting is when there is a downhill movement due to gravity thatconsists of soil or rock material and refers to all fast-movingmaterial. Debris flow is a common type of mass wasting that consists ofrapid movement. “Flows are rapidly moving mass-wasting events in whichthe loose material is typically mixed with abundant water, creating longrun-outs at the slope base” (Johnson, Affolter, Inkenbrandt, &Mosher, 2017). There are two types of flows: debris flow which is madeup of coarse material, and earth flow which is made up of finermaterial.

Debris flow commonly occurs from heavy rains with falls beforeflowing downhill and creating sections with a surface broken by ridgesand channels. Hilly areas that are subject to long, heavy rainfalls aremore susceptible to experiencing debris flow. In the United States,examples of these areas include Hawaii, northern California, Idaho,Washington, and Oregon on the West, and the Appalachian Mountains on theCentral and East.

An example of debris flow in the United States actually occurredtwice in the same location! In 1995, La Conchita, California experiencedmoving earth flow that damaged nine homes. A short week later, debrisflow occurred in the same exact location damaging five more homes. Thetop of this slide actually had early warning signs with its tensioncracks that eventually grew larger with the heavy rainfall during thewinter of 1994/1995. This was likely the trigger that caused the earthflow and debris flow events in 1995. Again in 2005, ten years later, arapid-debris flow occurred after the end of a 15-day rainfall.“Vegetation remained relatively intact as it was rafted on the surfaceof the rapid flow, indicating that much of the landslide mass simply wasbeing carried on a presumably much more saturated and fluidized layerbeneath” (Johnson, Affolter, Inkenbrandt, & Mosher, 2017). Thisevent damaged 36 homes and killed 10 people.

References:
Johnson, C., Affolter, M., Inkenbrandt, P., &Mosher, C. (2017). An introduction to geology. Salt Lake CommunityCollege. Open Educational Resource. Retrieved fromhttp://opengeology.org/textbook/

POST2:

Debrisflow is a type of mass wasting. A debris flow is a moving mass of loosemud, sand, soil, rock, water, and air that travels down a slope underthe influence of gravity. To be considered a debris flow, the movingmaterial must be loose and capable of flowing down the slope. Usually,the flow is not fast and it creeps down the slopes. However, the fastones are the ones that attract attention and become very dangerous. Thespeed and volume of debris flows make them very dangerous. Every year,worldwide, many people are killed by debris flows. This hazard can bereduced by identifying areas that can potentially produce debris flows,educating people who live in those areas and govern them, limitingdevelopment in debris flow hazard areas, and developing a debris flowmitigation plan.

Highly destructive debris flows occur in many areas across the UnitedStates. Hilly areas subject to prolonged, intense rainfall areparticularly susceptible. Areas throughout southern California and SanFrancisco Bay Area, where I live, are frequently beset by debris flowproblems, and public agencies have expended vast resources on massivedebris-protection systems. Montecito, a city in California, has been avictim of one of the deadliest debris flow. In January of 2018,Montecito experienced heavy rainfall in a short period of time, causingwater, mud, trees, rocks, and boulders from the Santa Ynez Mountains toflow down creeks and streams into the Montecito area.