1 / 10

WEATHERING - PowerPoint PPT Presentation

  • Uploaded on

WEATHERING. BY MS. HOUSTON ARMS 6 TH GRADE EARTH SCIENCE. Weathering. Natural process that breaks down rock into sediment (sand, silt, clay) B egins the process of forming soil from rock and sediment. Affects sediment particle size and soil texture. Mechanical Weathering.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' WEATHERING' - garron

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript






Natural process that breaks down rock into sediment (sand, silt, clay)

Begins the process of forming soil from rock and sediment.

Affects sediment particle size and soil texture.

Mechanical weathering
Mechanical Weathering

Physical process that breaks down rock but does not change the composition of rock.

Burrowing Animals

Ice Wedging

Plant Roots



Mechanical weathering1
Mechanical Weathering

  • Ice wedging is the process that occurs when water freezes, expands and thaws in the cracks of a rock

  • Overtime the cracks will get wider and deeper and the rock will break

  • Plant growth causes rock to break by roots exerting pressure on the rock

  • Plant roots can seek their way into rock cracks and continue to grow creating pressure in the cracks of rock.

Mechanical weathering2
Mechanical Weathering

  • Burrowing animals dig tunnels in the ground loosening small rocks and sediment and eventually pushing them to the surface

  • Wind carries other sediment and potentially beat on the surface of other rock loosening or breaking other rock

  • Water can exert pressure on sediment and small rock thereby further breaking the rock.

Chemical weathering
Chemical Weathering

Chemical process that breaks down rock by chemical reactions that dissolve minerals or change them into different minerals.

Rock composition will change!

Carbonic acid

Natural plant acids


Acid rain

Chemical weathering natural acids
Chemical Weathering-Natural Acids

  • Carbonic acid forms when water reacts w/ carbon dioxide gas in the air.

  • Carbonic acid is a weak acid that can dissolve some minerals found in rock.

  • Carbonic acid dissolvescalcite a mineral found in limestone

  • Ex: cave formation

  • Other natural acids can dissolve the mineral feldspar which is found in granite, some types of sandstone and other rocks.

  • Kaolinite is a clay mineral found in some soil and is formed fromdissolved (broken down) feldspar.

Chemical weathering plant acids and oxidation
Chemical Weathering-Plant Acids and Oxidation

  • Plant roots give off acids

  • These acids can dissolve some minerals found in rock making the rock weak and causing the rock to break into smaller pieces

  • Oxidation occurs when oxygen gas and moisture react with certain materials to form a new material

  • This new material looks like rust.

  • Oxidation of minerals gives some rock a red or rust color

Effects of climate and rock type
Effects of Climate and Rock Type

  • Climate affects the rate (how fast) weathering occurs

  • Cold, polar climates increases MECHANCAL weathering

  • Warm, wet climates increases CHEMICAL weathering

  • Desert climate slows CHEMICAL weathering

  • Cold, polar climates slows CHEMICAL weathering

For additional information
For Additional Information:

See the Glencoe textbook. You may access the textbook online via the ARMS website.

Click on Academics

Click on Science Information

Click on Online Textbook and look for the 6th Grade textbook.

Highlight and copy the code

Click on the 6th grade textbook and paste the code the click submit.

If you can not access the book, make sure that you have the latest version of Adobe reader then repeat the steps