Deposition, Weathering, and Erosion JH - KEADLE Deposition, Weathering, and Erosion

Weathering

What Caused This? http://commons.wikimedia.org/wiki/File:Toad_Rock_-_geograph.org.uk_-_767454.jpg http://en.wikipedia.org/wiki/File:KharazaArch.jpg

vocabulary word! weathering - is a process that breaks down rock and other substances at Earth’s surface very slow process creates soil softer rock weathers faster weathering is fastest in hot and wet climates

Types of Weathering mechanical weathering chemical weathering

What is Mechanical Weathering? vocabulary word! mechanical weathering - breakdown of rock into smaller pieces without any change in the chemical composition of its minerals. Sometimes called “physical” weathering Rock is torn apart by physical force, rather than by chemical breakdown.

Mechanical Weathering ice wedging exfoliation thermal expansion biotic

Mechanical - Ice Wedging vocabulary word! ice wedging - occurs when water fills cracks in rock then freezes and thaws over a long period of time. The expanding ice cause the rock to eventually break.

Mechanical - Exfoliation vocabulary word! exfoliation - rock breaks off into leaves or sheets along joints which are parallel to the ground surface.

Mechanical - Thermal vocabulary word! thermal weathering - rock split by daily heating and cooling as different minerals in the rock expand and contract.

Mechanical - Biotic vocabulary word! biotic weathering - weathering caused by living organisms plant roots, digging animals, microscopic plants and animals, algae and fungi.

Mechanical Weathering

Demo 1 Mechanical Weathering https://www.youtube.com/watch?v=-R3kP_CJfkQ&ibss=1

What is Chemical Weathering? vocabulary word! chemical weathering - breakdown of rock into smaller pieces because of change in the chemical composition of its minerals. Chemical reactions break down the bonds holding the rocks together, causing them to fall apart. Chemical weathering occurs in all types of rock but smaller rocks are more susceptible because they have a greater amount of surface area.

Chemical Weathering Types of chemical weathering oxidation (oxygen) hydrolysis (water) carbonation (carbon dioxide) biotic (living organisms) acid rain

Chemical - Oxidation vocabulary word! oxidation - oxygen combines with elements in rocks to form new types of rock. Often, there is a rusting effect on the rock.

Chemical - Hydrolysis vocabulary word! hydrolysis - water combines with the substances in rocks to form new types of rock.

Chemical - Carbonation vocabulary word! carbonation – carbon dioxide is dissolved in water making carbonic acid, which eats away at the rock. Weak acid is formed when carbon dioxide in the air mixes with rain. This is the same acid found in soft drinks. 

Chemical - Biotic vocabulary word! biotic - living organisms can cause changes in the chemistry of rock. Plants lower the local pH to make it more acidic Bacteria act as catalysts in various geochemical processes

Chemical Weathering

Demo 2 Chemical Weathering https://www.youtube.com/watch?v=WvCLp1OuQt0&ibss=1

Weathering by Water Water is the strongest agent of chemical weathering It can dissolve rock and minerals in rock

Weathering by Waves Waves weather the land: Mechanical weathering Broken down into smaller pieces Chemical weathering Dissolved in water

Weathering by Waves

Weathering by Wind Wind weathers the land by mechanical means abrasion Very slow process

Weathering by Wind

mechanical weathering The breaking down of rock into smaller pieces that remain next to each other. Weathering forms sediments mechanical weathering chemical weathering Physical breaking of rock without any change in the chemical composition of the rock. The breaking down of rock into smaller pieces because of chemical changes within the rock. ice wedging biotic force biotic oxidation exfoliation thermal hydrolysis carbonation

Erosion

What Caused This? http://commons.wikimedia.org/wiki/File:Water_erosion_below_Hay_Bluff_-_geograph.org.uk_-_1074175.jpg http://commons.wikimedia.org/wiki/File:Wind_erosion_Seminole_Canyon.JPG http://commons.wikimedia.org/wiki/File:Baventian_Clay_Beds_-_geograph.org.uk_-_1776748.jpg

Erosion erosion - movement of weathered rock and soil to a new location. gravity water glaciers waves wind

What Is Gravitational Erosion? downward movement of rock and sediments, mainly due to the force of gravity.

Erosion by Gravity Gravity can erode landscapes Landslides Mudflow Slump Creep

Erosion by Water Moving water is the strongest agent of erosion that has shaped Earth’s land surface. Erosion by water starts with rain. As the rain runs downhill, it carries soil rock and other material with it.

Erosion by Water The rate depends on amount of rain, vegetation, type of soil, shape of land, and how people use the land As water moves fast, it picks up sediment As water slows down, it drops sediment

Water

What Is Glacial Erosion? moves and carries rocks, grinding the rocks beneath the glacier Glaciers pluck and abrade to cause erosion.

Erosion by Glaciers

What Is Wave Erosion? Waves - relentless pounding of waves that erodes the weaker, softer rock Can take over 100 years to erode a rock to sand

Erosion by Waves When waves hit rocky coastlines, the impact can break off pieces of the rock The sand and sediment in the waves can also act like sandpaper and wear away rock

Waves

Station 3 Wave Erosion https://www.youtube.com/watch?v=y0C5sQ_NWs8&ibss=1

What Is Wind Erosion? wind picks up surface material and moves it, weakest agent of erosion responsible for creating great deserts like the Sahara Desert and Gobi

Wind

Station 4 Wind Erosion https://www.youtube.com/watch?v=Prh7y8sN-g8&ibss=1

erosion Movement of sediments from one place to another. wind glaciers water gravity waves

Deposition

Deposition vocabulary word! deposition - laying down (dropping) of sediment carried by wind, water, or ice

Deposition by Water Water is the strongest agent of deposition. Rivers deposit soil and sediment on their flood plains and deltas Good farmland is usually based on land where sediment was deposited by water

Deposition by Water Water Deposition

Deposition by Glaciers When a glacier melts, it deposits the sediment it eroded from the land This deposition can create new landforms and deposit sediment in new areas till – material deposited on the land’s surface moraine – ridge at the edge of a glacier

Glacier Deposition

Deposition by Waves Waves shape coastlines by depositing sand on the beach. The type of sand is determined by the sediment on the ocean floor white sand black sand pink sand green sand

Deposition by Waves

Deposition by Wind Wind is the weakest agent of deposition. When it drops the sediment it is carrying, it can form dunes or mounds .

Deposition by Wind

deposition Laying down of sediment that was carried in from another place. wind water waves glacier

Wind, water, and waves work together in the processes of deposition, weathering, and erosion.

What’s the Difference? WEATHERING - think weather wearing rock down EROSION - think of a road and traveling DEPOSITION – think of depositing money in a bank