Sedimentary Rock Display

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Weathering Versus Erosion

Weathering:• Refers to the movement of solids such rock, soil, mud,

and other particles caused by agents of currents like water, ice or wind.

Erosion:.• Refers to the disintegration of soil, and mineral and rocks

that are in direct connection with the atmosphere.

WEATHERING can be broken down into two categories:

1. Chemical Weathering –• Is involved when a chemical change

occurs in the mineral. The chemical reactions break the bonds that holds the rock together

2. Mechanical Weathering –• Is involved when the physical

qualities of the rock have been fragmented and disintegrated without having any chemical reactions.

***Both weathering types occur in one concurrence with one to another and the effects are extremely difficult to differentiate.

EROSION results from gravity and the following 3 types of flowing agents:

1. Water Erosion – • a set of natural courses that comprises of

dissolution, abrasion, corrosion, weathering, and transportation of the material that has been worn away from the surface of the Earth.

2. Wind Erosion –• refers to the transportation, deposition,

and erosion of the Earth’s surface which brought about by the wind, especially during dust storms.

3. Ice Erosion - • is typically caused by freezing of the

water in the rocks’ fissures.

Explanation of Weathering and Erosion

Chemical Weathering: Is the breakdown of rocks (weathering)

caused by chemical reactions. Chemical weathering modifies the

composition of the rock material found in the surface. A good example is clay.

Mechanical Weathering:• Breakdown or the erosion of rocks into

smaller parts or fragments • The changes are purely physical and no

chemical reactions involved.

Chemical Weathering

Mechanical Weathering

Different types of Weathering

Interesting FactsWater Erosion refers to any erosion type caused by water. It includes the following:

Splash Erosion:This type happens due to falling

raindrops’ impact

Sheet Erosion:Is a slow-

acting erosion and happens

when soil particles are conveyed by rolling in the ground by a thin film of

water or sheet wash.

Rill Erosion: This refers

to the elimination of surface materials

and changes them into another material.

Gully Erosion:

This refers to the type of

erosion caused by

running water.

Stream Erosion:Refers to

the elimination of surface

matter through a

stream passage.

Different types of Erosion

Native American Leaders

Wind Erosion –• Refers to the transportation,

deposition and the erosion of the soil on the Earth’s surface by the wind. It happens especially during dust storms.

Ice Erosion - • is typically caused by freezing of

water in rock fissures.

Difference between Wind and ice Erosion

Fossil content can usually be found on sedimentary rocks. Such fossils cannot be found in the crystalline igneous and metamorphic rocks.

usually formed on the Earth’s surface

made possible when rock particles are moved by air, ice, wind and are placed on the dry lands and in the aquatic environments.

Explanation of the role of the Plate Tectonics

US Geological Survey. (1999). Difference: Weathering & Erosion. Retrieved from http://www.nature.nps.gov/geology/usgsnps/misc/gweaero.html on =

Marlimiller. (N.D). Chemical Weathering. Retrieved from http://marlimillerphoto.com/chemical.html

BCSSA. (N.D). Mechanical Weathering. Retrieved from http://www.bcssa.org/newsroom/scholarships/great8sci/Earth/Changing_Surface/WeatheringErosion/Mechanical_Weathering.html on

The National Soil Erosion Research Laboratory. (N.D). Rill Erosion. Retrieved from http://milford.nserl.purdue.edu/weppdocs/overview/rill.html

Erosion and Sediment Control Measures. (N.D). Erosion Process. Retrieved from http://dhn.iihr.uiowa.edu/runoff/erosion.htm

KSRE. (N.D). Wind Erosion. Retrieved from http://www.ksre.ksu.edu/fieldday/kids/wind/erosion.htmFLickr. (N.D). Ice Erosion. Retrieved from http://www.flickr.com/photos/nickrussill/233819006/in/photostream/Sedimentary Rocks (N.D). Sedimentary RocksRetrieved from http://users.forthnet.gr/ath/nikolas_c/sedimentary_rocks.htm

References