weathering for sci 8
TRANSCRIPT
statue Grand Canyon
Sand Pile
What doThese 3 Things Have in
Common??
They have all been
subjected to the
process of
WEATHERING
WEATHERING: isTHE CHEMICAL AND PHYSICALPROCESS THAT
CHANGES ROCK
For weathering to occur the rocks must
be exposed to:
WATER (hydrosphere)AIR (atmosphere)
ACTION OF HUMANS & OTHER LIVING ORGANISMS
Evidence of Weathering:
the end product of theweathering of rock is
SEDIMENT
PHYSICAL WEATHERING:
ROCKS ARE BROKEN INTO SMALLER PIECES WITHOUT CHANGING THE
CHEMICAL NATURE OF THE ROCK
Explain how water and wind
can can causephysical
weathering in the
following ways:
The alternate freezing
andthawing of
water
WATER EXPANDSWHEN IT FREEZES
This is called…….
Ice Wedging or Frost Action
a weathered sidewalk
Half Dome in Yosemite California
*ABRASION
RUNNING WATER AND WIND CAN RUB OR WEAR DOWN ROCKS
RUNNING WATER ANDWIND CAN CAUSEROCKS TO RUB AGAINSTEACH OTHER AND WEARTHEM DOWN
* BIOLOGIC ACTIVITY
A sidewalk being lifted by the tree roots!!
PLANT ROOTSEXPOSES NEW SURFACES TO WEATHERING
*Humans can influence the rate of weathering by
theuse of powerful
equipment
If you increase the surface area
you will ___________ the rate of weathering
increase
Surface area
rateof
weathering
CHEMICAL WEATHERING:
Rocks are broken and the chemical composition is also ___________CHANGED
•OXIDATION OCCURS WHEN __________ FROM AIR COMBINES WITH ___________ TO FORM OXIDES
OXYGEN
MINERALS
RUST
This was washed up on a beach!!
A rusty gate……
•CARBONATION
OCCURS WHEN __________ CONTAINING
__________ ACID
DISSOLVES MINERALS
WATER
CARBONIC
EX.
LIMESTONE CAVES
* POLLUTANTScan speed up
the rate ofchemical weathering
OXIDES OF SULFER AND NITROGEN MAKE RAINWATER UNNATURALLY ACIDIC
ACID RAIN
•HYDRATIONOCCURS WHEN _______ SUCH AS MICA AND FELDSPAR ABSORB ________ AND WEAKEN AND FORM ________
MINERALS
WATERCLAY
CLIMATIC EFFECTS ON WEATHERING:
PHYSICAL WEATHERING DOMINATES IN
COLD,MOIST
CLIMATES
CLIMATIC EFFECTS ON WEATHERING:
CHEMICAL WEATHERING DOMINATES IN
WARM, MOIST
CLIMATES
IN GENERAL WHEN THERE IS MORE
THERE IS MOREWEATHERING
MOISTURE
CLEOPATRA’S NEEDLECentral
Park
RATE OF WEATHERING ALSO
DEPENDS ON:
MINERAL COMPOSITION
ROCK RESISTANCE(HARDNESS)
SHALE
SANDSTONE
SHALE
SANDSTONELIMESTONE
SHALE
DOLOSTONE WHICH ROCK IS THE MOST
RESISTANT TO
WEATHERING?
WATER
SHALE
SANDSTONE
SHALE
SANDSTONELIMESTONE
SHALE
DOLOSTONE WHICH ROCK IS THE MOST
RESISTANT TO
WEATHERING?
SHALE
SANDSTONE
SHALE
SANDSTONELIMESTONE
SHALE
WHICH ROCK IS THE LEAST
RESISTANT TO
WEATHERING?
DOLOSTONE
SHALE
SANDSTONE
SHALE
SANDSTONELIMESTONE
SHALE
WHICH ROCK IS THE LEAST
RESISTANT TO
WEATHERING?
DOLOSTONE
SOIL FORMATION:SOIL IS THE
COMBINATION OF:
ROCK PARTICLESMINERALSORGANIC MATTER
THE END RESULT OF WEATHERING AND BIOLOGIC
ACTIVITY IS:
Adding to a compost pile
EROSION:TRANSPORT OF SEDIMENTS
AND DEPOSITIN
G THEM
ELSEWHERE
EROSION IS DRIVEN BY THE FORCE OF
EROSION IS DRIVEN BY THE FORCE OF
GRAVITY
THE AGENTS OF EROSION ARE:
RUNNING WATERWINDMOVING ICE (GLACIERS)
Each Agent of Erosion Produces
it’s Own Characteristic
shape and Texture in the
Sediment :
ROUNDS AND
SMOOTHESTHE ROCK SURFACE
ALSO MAKES ITSMALLER
WIND BLOWN SEDIMENTS
FROST AND PIT THE ROCKSURFACE
SMALL SEDIMENTS IN THE GLACIER POLISHES & SMOOTHES
THE ROCK SURFACE
LARGE SEDIMENTS SCRATCH AND STRIATE THE ROCK SURFACE
FALLEN ROCKS ARESHARP &ANGULAR
RUNNING WATER
The primary agent of erosion
is:
Colorado River
Grand Canyon
Niagra Falls