1 / 17

Chapter 6 Weathering and Soil

Chapter 6 Weathering and Soil . Types of Weathering. Mechanical Weathering – Breaks apart rock without changing its chemical composition Examples Plant roots grow into the cracks of rocks Animals burrowing Ice Wedging. Types of Weathering.

rollo
Download Presentation

Chapter 6 Weathering and Soil

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 6Weathering and Soil

  2. Types of Weathering • Mechanical Weathering – Breaks apart rock without changing its chemical composition • Examples • Plant roots grow into the cracks of rocks • Animals burrowing • Ice Wedging

  3. Types of Weathering • Chemical Weathering – Breaks up rocks due to a change in their chemical composition. (Water and Oxygen are factors) • Examples • Acid Rain • Rust

  4. Mechanical vs. Chemical Chemical Mechanical

  5. Ice Wedging • Type of mechanical weathering • This happens when water gets inside rocks, freezes, and then expands causing the rock to break.

  6. Carbonic Acid • When water mixes with carbon dioxide in the air, carbonic acid forms. • Type of chemical weathering • Comes in contact with different rocks, and reacts with the minerals in them.

  7. Oxidation • Oxidation occurs when a material is exposed to water and the oxygen in the air. • This causes “rust” • Type of chemical weathering.

  8. Climate and Weathering • Cold climates – mechanical weathering breaks down rocks rapidly through ice wedging • Chemical weathering is more rapid in warm, wet climates. (tropical areas) • Lack of moisture and cold climates keeps chemical weathering at a minimum.

  9. What is Soil? • Soil – A mixture of weathered rocks, decaying organic matter (plants & animals), mineral fragments, water, and air. • Sediments + Organic Matter = Soil

  10. What is Humus? • Humus – Dark colored organic matter found in soil; made of decayed plants and animals.

  11. Soil Profile – Vertical section of the different soil layers. • Horizon – Each layer in the soil profile. (Three Horizons: A, B, and C)

  12. Horizons • Horizon A • Most evolved • Known as topsoil • More humus and smaller rock and mineral particles than other layers. • Horizon B • Less evolved • Lighter in color • Some plant roots reach here

  13. Horizons Continued • Horizon C • Bottom layer of soil profile • Contains partly weathered rock • Solid rock

  14. Layers of Soil

  15. Process of Soil Formation

  16. Leaching • Removal of soil materials dissolved in water. • Occurs throughout all three Horizons.

  17. When does Desertification occur? • When soil is dry due to lack of rain combined with poor farming practices and over – grazing.

More Related