Download Grand Canyon

Earth Surface changes
• Changes to Earth’s surface happen over time.
• Some changes are due cataclysmic events like
volcanoes erupting, or earthquakes.
• These changes are fast and violent.
Slow changes
• Other forces change Earth slowly.
• The sun’s energy drives wind, water,
temperature changes, and life forms that can
change the Earth.
• Slow changes are called weathering.
Physical Weathering
• The Earth’s surface is made of rock and soil.
• Rocks form from different processes.
Minerals
• Rocks are made of minerals.
• Minerals are elements that have been
combined together by chemical reactions.
• Some minerals are pure like gold and some
minerals are combinations like salt.
Properties
• Minerals have different physical properties.
1. Color
2. Luster
3. Hardness
4. Streak
5. Cleavage
mineral id 9:48
Mohs Hardness Scale
• A way to identify minerals is to use the scratch
test and identify the mineral with a scale.
• What other ways could you use to identify
minerals?
Rocks
• Minerals combine to form rocks. Scientists
classify rocks according to how they are
formed.
Igneous Rocks
• When magma cools igneous rocks form.
• You can identify igneous rocks by the crystals
or holes formed by gas bubbles.
• Most dark colored rocks are igneous.
obsidian
granite
Pumice
Sedimentary
• Formed by sediments.
• Sediments are pressed and cemented
together.
• May contain fossils.
sandstone
Metamorphic
• Rocks that are pushed underground deep into
the crust can be heated again.
• Sedimentary and igneous rocks that are
reheated can change into igneous rocks.
gneiss
• Look for ribbonlike layers.
Rock Cycle
• Rocks can go from one type to another by the
rock cycle.
Rock cycle
rock cycle vid
Rock cycle
geology kitchen
Rock cycle
Weathering by water
• Water causes weathering by
1. Freezing and cracking rocks
2. Water in rivers and streams makes rocks in
the water move. Rocks break into smaller
pieces.
3. Water carries sand or pebbles that will rub
against rocks and wear them down.
rock weathering video
Weathering by wind
• Wind picks up sand and blows the sand
against rock.
• The wind wears down the rock and changes
the rock.
Living things
• Roots and plants grow in cracks in rocks and
widen cracks in the rock and break them up.
Chemical Weathering
• Rainwater and groundwater join with carbon
dioxide gas from the air to form a weak acid.
• The acid wears away the rock.
• Forms caves over time.
• Caves form in sedimentary rock (limestone)
Soil
• Soil is made of layers.
• The layers are different from other layers.
1. Undecayed (humus)
2. Topsoil: loose rich soil, holds lots of humus
and minerals. Good for plants.
3. Subsoil: Holds many minerals, where you find
clay.
4. Rock: Weathered rock and bedrock
Layers of the Soil
Running Water
• Gravity makes the water move. Loose soil gets
pulled in the water.
• The draining water is called runoff. Runoff
carries soil, sand, and small rocks.
• The runoff deposits sediments at the bottom
of the river, this is called deposition.
Waves
• Waves pound on the shore.
• Energy in the wave break up rocks into smaller
rocks.
• Change rough rocks to smooth rocks.
• The wave action will erode away the
shoreline.
• Makes haystacks on the Washington and
Oregon coast.
Gravity and Mass movement
• Gravity pulls large masses down mountains
and hills.
• This mass movement in the mountains are
called avalanches.
• The mass movement in hills are called
landslides or mudslides.
• Can happen fast like a mudflow or slow with
creep.
Groundwater
• When rain falls or ice melts some of the water
goes into the ground.
• Water will mix with CO2 to form a weak acid
that weathers the limestone.
• Water will seep into tiny holes in the rocks.
• Groundwater will form caves.
• Water evaporates leaving minerals that build
stalagmites and stalagtites.
Wind
• Strong winds pick up sand, and small pebbles.
• These winds can weather rock. Rocks will
break into smaller rocks.
• Erosion happens when these smaller rocks
and sand move from the power of the wind.
• When winds slow down, the sand and dirt is
deposited in a new place.
• The Dust bowl happened when there was a lot of
wind blowing dust. The topsoil needed to grow food
was deposited hundreds of miles away.
Glaciers
• Large masses of water that are on mountains.
• We depend on glaciers for our water and
electricity.
• Glaciers move slowly because of gravity.
• Glaciers push snow, sands, and rocks ahead of
it called glacial till.
• Valley glaciers carve out the valleys on
mountains.
• Glaciers cover 10% of the Earth’s land.
Weathering and Erosion
• What is the difference?
Bill Nye
What formed the Grand Canyon?
river formations
Fossils
• Form in sedimentary rock.
• We use fossils to learn about the past. Some
fossils have been dated to be hundreds of
millions years old.
• Fossils give us clues about Earth’s history.
Trace fossils
• Tell us how and
where an organism
lived.
• Tracks, burrows,
nests, animal
waste, tooth marks
are all trace fossils.
Body Fossils
• Show us what the plant
or animal looked like.
• Petrified fossils: minerals
in groundwater seep into
the remains and harden.
• Most dinosaur fossils are
body fossils.
Mold Fossils
• Plants or animals are
covered by sediments.
• Sediments harden and turn
into rock.
• Groundwater dissolves the
organism.
• A hollow space is left.
Amber fossils
• Insects become
trapped in tree sap.
• Insects are
preserved when
the sap hardens
into amber.
dino dna
Erosion Jigsaw
• Each group will be assigned a reading section in
the Erosion delta reader.
• Each member needs to read the section and take
notes in their journal.
• Once all notes are taken, the group will design a
poster that highlights the most important
information. (The poster has to have words and
pictures on it. Font needs to be Word Wall size.
• Reporter and a partner will present to the class.
• Class will take notes.
Groups
•
•
•
•
•
•
Group 1 – Running water pg. 9
Group 2 – Waves pg. 10
Group 3 – Gravity and mass movement pg 11
Group 4 – Groundwater (12)
Group 5 – Wind (12-13)
Group 6 – Glaciers (Glaciers)
What formed the Grand Canyon?
Claim: Scientists believe that the grand canyon
was formed from the Colorado River.
Evidence: Use evidence from your lab to explain
how they could come to that conclusion.
Possible Evidence
• Draw picture
• Use vocab from the landforms sheet
Weathering and Erosion Wrap up