Transcript Weathering: the process that breaks down rock and other

Weathering:
the process that breaks down rock
and other substances on Earth’s
surface
types of weathering:
1) mechanical weathering- rock is physically broken down into
smaller pieces
• Examples:
• a) freezing and thawing- water seeps into permeable (soil
that has tiny holes in it) soil or rock and then freezes and
expands
• b) plant roots- pry apart cracks in rocks
• c) animal actions- claws dig into rock
• d) abrasion- the grinding away of rock by other rock
particles
• e) ice wedging- ice widens and deepens cracks in rocks
•
View animation:
http://www.phschool.com/webcodes10/index.cfm?wcprefix=cfp&wcsuffix=2022&fuseaction
=home.gotoWebCode&x=10&y=13
pictures of examples of mechanical
weathering:
• http://www.classzone.com/books/earth_scien
ce/terc/content/visualizations/es1201/es1201
page01.cfm?chapter_no=visualization
• BrainPOP movie:
• http://www.brainpop.com/science/weather/
weathering/
2) chemical weathering- the process that breaks
down rock through chemical changes
Examples:
a) acid rain-produced by burning fossil fuels
b) plant roots-secrete acids into cracks in rocks
c) reaction with oxygen to cause rust
d) dissolving by water
e) CO2 dissolves in water to form carbonic acid
that weathers limestone
and marble
View this animation of chemical
weathering:
• http://www.classzone.com/books/earth_scien
ce/terc/content/visualizations/es1202/es1202
page01.cfm?chapter_no=visualization
• http://www.bbc.co.uk/scotland/education/int
/geog/limestone/underground/index.shtml
• Cave formation:
• http://www.bbc.co.uk/scotland/education/int
/geog/limestone/underground/in_the_cave.s
html
View this animation to learn more about
weathering and how it is affected by the
climate of an area.
• Factors that affect the rate of weathering of
rock:
• a) type of rock
• b) climate- hot, wet climates cause chemical
weathering faster; cool, wet climates cause
mechanical weathering to occur
http://www.as.uky.edu/academics/departments_programs/EarthEnvironmen
talSciences/EarthEnvironmentalSciences/Educational%20Materials/Docu
ments/elearning/module07swf.swf
erosion- the movement of rock particles by
wind, water, ice or gravity
Examples of landscapes formed by erosion:
• http://www.classzone.com/books/earth_scien
ce/terc/content/visualizations/es1205/es1205
page01.cfm?chapter_no=visualization
• View short video:
• http://www.brainpop.com/science/earthsyste
m/erosion/