weathering, erosion, mass wasting
DESCRIPTION
this presentation is all about weathering, erosion, & mass wasting. this may be simple, but it is good for the eyes, and the information is short but complete. :))TRANSCRIPT
WEATHERING, SOIL, AND
MASS WASTING
DIFFERENCIATING EXTERNAL PROCESSES & INTERNAL PROCESSES
• External process- processes that occur at or near Earth’s surface and powered by the energy from the Sun
• Internal Process- processes that occur underneath the Earth’s surface and derives its energy from Earth’s interior
THREE EARTH’S EXTERNAL PROCESSES
1. Weathering
2. Mass Wasting
3. Erosion
WEATHERING- the physical breakdown & chemical
decomposition of rocks- part of the rock cycle- considered as a preparation for erosion- rocks are damaged physically and/or
chemically
AGENTS OF WEATHERING:• change of the environment
• Water
• air/wind
• human activities
• chemical substances
KINDS OF WEATHERING
1. Mechanical Weathering
2. Chemical Weathering
MECHANICAL WEATHERING- rock is broken to smaller pieces without
changing its chemical composition
- increases the amt. of surface available for chemical weathering
- results in smaller pieces from a single large one
4 PROCESSES OF MECHANICAL WEATHERING
a. Frost Wedging- caused by the freezing and thawing of water that seeps into cracks of rocks
b. Abrasion- caused by the rubbing and/or bouncing of rocks with each other
c. Exfoliation/Unloading- peeling away of large sheets of loosened materials in the rock
d. Biological Activities- caused by an organism’s activity such as plants, burrowing animals & humans
FROST WEDGING
EXFOLIATION
ABRASION
CHEMICAL WEATHERING - rock is broken down by chemical action
resulting in the change of the composition of the rock
AGENTS: 1. Oxygen 3. carbon dioxide2. Rainwater 4. acids produced by
decaying organisms
2 PROCESSES OF CHEMICAL WEATHERING
a. Oxidation- mineral is interacted chemically by oxygen
b. Hydration- mineral is interacted chemically by water
c. Carbonation- mineral is interacted chemically by carbon dioxide or carbonic acid
BAUXITE- COMBINATION OF OXYGEN, HYDROGEN & ALUMINUM
HEMATITE FORMED BY OXIDATION
EROSION- physical removal of the material- transporting of the rock from one place
to anotherAGENTS:1. Wind2. Water3. Ice
SHEET AND WIND EROSION
• Sheet erosion- soil is removed by thin sheets of water
• Wind erosion- caused by wind and only very significant during windy days or during a drought
RILLS AND GULLIES
• Rills- narrow incision of soil caused by overland flow
• Gully- landform created by running water which sharply eroded the land, typically on a hillside
GULLY
RILLS
MASS WASTING
- Movement of rock, regolith & soil under the direct influence of gravity
- The step that follows weathering
AGENTS OF MASS WASTING:1. Gravity- main controlling force2. Trigger- initiates downslope movements3. Water- heavy rains, snowmelt4. Over steepened Slopes5. Removal of Vegetation6. Natural Calamities
MOTION TYPES OF MASS WASTING1. fall- slopes which are too steep (ex.
Rockfall)2. Slides- materials remain fairly &
coherent & moves along a well defined surface (ex. Landslide)
3. Flow- moves downslope as a vicious FLUID (ex. Mudflow)
4. Slump- downward sliding of a mass
AVALANCHE L
ANDSLIDE
R O C K F A L L
THE END
BIBLOIGRAPHY:• Tarbuck, Edward and Lutgens, Frederick. Earth
Science: Basic Principles and Concepts, Pearson Education South Asia Pte Ltd. 23-25 First Lok Yang Road, Jurong Singapore
• http://www.regentsprep.org• http://www.google.com• http://images.google.com.ph/imghp?hl=en&t
ab=wi
THANKS FOR WATCHING!
By: Russel Christine CorcinoMSU-IIT IDS