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

*ABRASION

RUNNING WATER AND WIND CAN RUB OR WEAR DOWN ROCKS

* BIOLOGIC ACTIVITY

A sidewalk being lifted by the tree roots!!

*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

•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

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