Constructive and Destructive Processes 6 th Period a. Weathering and Erosion b. Crustal Deformation, Volcanic Eruptions, and Deposition

Vocabulary ● Land forms- one of the features that make up Earth's surface ● Weathering- the various mechanical and chemical process that causes exposed rock to decompose. ● Erosion- the process by which the surface of the Earth is worn away by the action of water, glaciers, winds, etc. ● Crustal Deformation- a change in shape of the Earth's crust. ● Decomposition- the state of being decomposed; decay. ● Deposition- the removal of an object; being deposited.

● Two types of weathering - ● Physical ● Chemical ● Types of physical weathering- ● thermal expansion ● freeze thaw weathering ● pressure release ● hydraulic action ● salt crystal growth weathering ● Types of chemical weathering- ● dissolution ● hydration ● hydrolysis ● oxidation ● biological weathering Weathering

Erosion ● The four main contributors to erosion are- ● water ● wind ● ice ● wave ● Water is erosional in all its forms. ● It is most erosional in streams ● Wind erosion is most powerful with rocks and sand ● Ice erosion occurs mostly from glaciers. ● Wave erosion occurs when waves from large bodies of water erode the coastline.

Crustal Deformation ● Deformation in rock involves ● changes in shape ● changes volume ● Changes in shape and volume occur when stress causes rock to fracture or crumple into bends in the rock. ● More complex bends in rock types can develop in situations where lateral pressures become greater.

Volcanic Eruptions - Caused by pressure build-up and plate tectonics - Largest volcanic eruption - eruption of Toba - occurred about 71,000 years ago - produced 2800 cubic kilometres of ash and may have reduced the world's human population to only 10,000 Weathering and Erosion - Arches National Park (See left photo) was created by weathering and erosion - Over 2,000 natural arches were formed over many years - This park exposed millions of years of geologic history HISTORICALINFOHISTORICALINFO

Real Life Application ● Weathering, erosion, and volcanic eruption impact humans in negative and positive ways. These are some of the impacts. ● Weathering and erosion makes a positive impact because it can cause fractures of rocks to erode into cool land formations such as arches. People are able to visit these sites and learn about how they are formed. Arches have different textures and can be found at national parks. ● Volcanic eruption can impact people in both a negative and positive way. It is negative because gases from volcanoes are dangerous and harmful. Also, a volcano will wipe out everything in its path when it erupts. It is positive because volcanoes have created great things like the Hawaiian Islands. ● Geologists study volcanic eruptions, erosion, and weathering, Seismologists and volcanologists study and help predict volcanic eruptions and earthquakes. Sedimentologists study erosion and deposition of rock particles by wind, water, or ice.

"References." Dictionary.com. Lexico Publishing Group, LLC. 1 Oct 2007.Dictionary.comhttp://dictionary.reference.com "Erosion - Information on Erosion." About.com The New York Times Company. 1 Oct 2007.About.comhttp://geography.about.com/od/physicalgeography/erosio n.htm "What Causes Volcanic Eruptions?." Thinquest. Oracle Education Foundation. 1 Oct m "Geology - What was the Biggest Volcanic Eruption in History?." Answers. The New York Times Company. 1 Oct n.htm "Arches." National Park Service. 23 Aug U.S. Department of the Interior. 1 Oct "Arches; Nature and Science / History." National Park Service. 02 Oct U.S. Department of the Interior. 1 Oct Bibliography

Graphics (Bibliography) This is a well known arch called Delicate Arch. This is a picture of a volcanic eruption of Mount Pinatubo. This is a photo of the Toba Caldera, This is a photo of the Double Arch. This is a photo of volcanic lava making new layers in the earth. This is a photo of weathering on the island of Paros, Greece.

Demonstration For our project we did a demonstration using a home- made volcano. We used frosting, and spread it over the volcano to show constructive processes like a volcanic eruption. Then we scraped the frosting off to show erosion, which occurs because of things like landslides, earth quakes, heavy rain and flooding.