Chapter 4 Earth's Dynamic Surface

Chapter 4 Earth's Dynamic Surface

Poll

Can you break down a mountain?

• yes

• no

Poll

Is Earth's surface made of tectonic plates?

• yes

• no

Poll

Most earthquakes occur near tectonic plate boundaries.

• true

• false

Poll

Tectonic plate motion is too slow to measure.

• true

• false

Plate Tectonics

​1. states that the Earth's surface is broken into large, rigid pieces that move with respect to each other.

​2. pieces are called tectonic plates

​3. forms volcanoes, mountains and causes earthquakes

​

Multiple Choice

What theory states that Earth's surface is broken into large, rigid piecs that move with respect to each other?

• gravity

• the water cycle

• evolution

• plate tectonics

Multiple Choice

what are the pieces of Earth that move called?

• dinner plates

• tectonic plates

• rocks

​What is a tectonic plate?

​1. the crust and uppermost part of the mantle make up the lithosphere

​2. the lithosphere forms a rigid shell that is broken into tectonic plates

​3. the partially melted portion of the mantle below the lithosphere is the asthenosphere

​4. the asthenosphere is hotter and can bend more easily.

Multiple Choice

What do we call the outermost layer of Earth that is made up of the crust and uppermost part of the mantle?

• asthenosphere

• lithosphere

• atmosphere

Multiple Choice

What is the partially melted portion of the mantle below the lithosphere called?

• asthenosphere

• lithosphere

• geopshere

• hydrosphere

​Plate Boundaries

​1. Scientists have identified 15 major tectonic plates

​2. Scientists describe a plate's motion by how it moves in relation to another plate.

​3. these motions create 3 types of boundaries.

​cont.

​4. divergent boundaries are a boundary where two plates move away from each other

​5. convergent boundaries are boundaries where two plates move away from each other

​6.. transform boundaries are where two plates slide past each other

Multiple Choice

a boundary where two plates move away from each other

• divergent

• convergent

• transform

• subduction

Multiple Choice

a boundary where two plates move toward each other is a

• divergent boundary

• convergent boundary

• transform boundary

• subduction

Multiple Choice

where two plates slide past each other

• divergent boundary

• convergent boundary

• transform boundary

• subduction

​cont.

​7. at convergent boundaries, some plates can be pushed under the other, creating subduction

​8. subduction is the process when one plate moves under another

​9. this pushes the plate down into the mantle

Multiple Choice

a process that occurs when one tectonic plate moves under another tectonic plate

• divergent boundary

• convergent boundary

• transform boundary

• subduction

Poll

Who has used a device with GPS?

• yes

• no

​Measuring Plate Movement

​1. scientists can now accurately measure plate movement using GPS

​2. GPS is a set of 24 satellites in orbit that send signals to pinpoint location

​3. movement is slow, but causes large changes over time.

​4. North America and Europe were once joined in a large continent called Pangea

​Why do tectonic plates move?

​1. When the mantle is heated by the core, it becomes less dense and rises, flowing along the underside of the crust.

​2. When it cools, it sinks back down because it becomes more dense.

​3. the circulation of this fluid caused by differences in density and thermal energy is called convection.

​

• ​mantle pushing up at ridge is called ridge push

• ​mantle sinking and pulling plate down is called slab pull

Multiple Choice

Which force doesn't contribute to tectonic plate movement?

• convection

• slab pull

• ridge push

• They all do!

Multiple Choice

________________ is circulation within fluids caused by differences in density and thermal energy.

• radiation

• convection

• conduction

• correction

​Shaping Earth's Surface

Lesson 2​

​Earthquakes

​1. an earthquake is the vibrations caused by the rupture and sudden movement of rocks along a break or a crack in Earth's crust.

​2. can damage natural and man made structures

3. earthquakes occur at faults.

​4. A fault is a crack or fracture in Earth's crust along which movement occurs.

Multiple Choice

A _________________ is the vibrations caused by the rupture and sudden movement of rocks along a break or a crack in Earth's crust

• earthquake

• fault

• tectonic plate

• volcano

Multiple Choice

A ________ is a crack or a fracture in Earth's crust along which movement occurs.

• earthquake

• fault

• tectonic plate

• volcano

​cont.

​5. faults do not continually move but forces build up and eventually release, causing a rupture and an earthquake

​6. most earthquakes occur at plate boundaries

​7. plate boundaries are long and do not rupture all at once

​8. the amount of energy released is called the magnitude

Multiple Choice

______  is a measurement of the amount of energy released during an earthquake

• magnitude

• fault

• earthquake

• volcano

Multiple Choice

Where do most earthquakes occur?

• in the sky

• plate boundaries

• inland

cont.

​9. faults are largest where the plate subducts into the mantle

​10. strongest earthquakes occur here

​11. faults can be many miles from the plate boundary

12. movement of these faults creates mountains, valleys and other landforms​

​

​

​

​transform bounary

• ​blocks of crust move horizontally past each other

• ​also called strike slip faults

​divergent boundary

• ​occurs where two plates move apart

• ​between oceanic plates, mid-ocean ridges are formed

• ​

• ​between continental plates, one side moves down, relative to the other, forming valleys

Multiple Choice

type of boundary formed where to blocks slide past each other

• transform 

• divergent

• convergent - subduction

• convergent - no subduction

Multiple Choice

type of boundary formed where two plates move apart from each other

• transform

• divergent

• convergent - subduction zone

• divergent - no subduction

​convergent boundary - subduction zone

• ​oceanic crust subducts or goes under continental crust

• ​crust that subducts, melts and forms volcanoes on the crumpled crust that does not subduct

​convergent boundary - no subduction

• ​edges of both plates become crumpled and deformed

• ​blocks of crust slide upward creating mountains

Multiple Choice

type of boundary where to plates collide and form a mountain range

• transform boundary

• divergent boundary

• convergent boundary - subduction

• convergent boundary - no subduction

Multiple Choice

type of boundary where one plate subducts under another, creating a volcanic arc

• transform boundary

• divergent boundary

• convergent boundary - subduction zone

• convergent boundary - no subduction

​Volcanoes

​1. molten rock below Earth is called magma

​2. magma that erupts to Earth's surface is called lava

​3. volcanoes are vents in Earth's crust through which molten rock flows

Multiple Choice

magma that erupts onto Earth's surface

• volcanoes

• lava

• magma

Multiple Choice

vents in Earth's crust through which molten rock flows

• lava

• volcanoes

• magma

Multiple Choice

molten rock stored beneath Earth's surface

• lava

• volcano

• magma

• c

​Fun Fact

• ​There have been more than 1,500 different volcanoes that have erupted in the last 10,000 years.

• ​Can you name any?

​cont.

​4. most volcanoes occur at convergent plate boundaries where one plate subducts under another.

​5. the rock melts and rises, forming volcanoes

​6. ex. Mount Hood, Mount Ranier, and Mount St. Helens

Multiple Choice

Where do volcanoes normally occur?

• at convergent plate boundaries

• underground

• i

​cont.

​7 volcanoes can form mountains, sometimes in thousands of years, sometimes much quicker

​8. volcanoes can erupt 2 ways; flowing and slowly hardening or violently exploding.

​

Multiple Choice

Volcanoes can erupt two ways.  Which one is not one of those ways.

• violent

• slow flowing

• as water

​Ocean Basins

​1. lava does not only erupt from volcanoes

​2. lava also erupts at divergent plate boundaries such as mid ocean ridges.

​3. this is where two oceanic plates are diverging, forming more oceanic crust.

​4. Mid-ocean ridges are long, narrrow mountains formed by magma at divergent boundaries.

Multiple Choice

__________ are long, narrrow mountains formed by magma at divergent boundaries

• tectonic plates

• volcanoes

• midocean ridges

• subduction zones

​mountains at convergent boundaries

​1. mountains form where the Earth's crust folds and crumples

​2. This usually occurs at the edges of plates

​3. This is why most mountains form near plate boundaries

4. When two continents collide at convergent plate boundaries, large mountain ranges form. ex. Himalaya mountains

Multiple Choice

Where do mountains usually form?

• divergent boundaries

• continental convergent boundaries

• sea floor spreading

Changing Earth's Surface​

Lesson 3​

​Breaking Down Earth's Materials

• ​The Appalacian mountains were formed a long time ago and since have been broken down

• ​rocks are broken down, and rounded, just like the castle

​Weathering

​1. Weathering refers to the mechanical and chemical processes that change Earth's surface over time.

​2. Weathering can break rock into smaller particles

​3. Sediment is the material formed from rocks broken down by weathering. These can be large rocks, sand, silt or clay

Multiple Choice

__________ refers to the mechanical and chemical processes that change Earth's surface over time.

• sediment

• tectonic plates

• weathering

Multiple Choice

_________ is the material formed from rocks broken down by weathering

• weathering

• sediment

• decay

​Physical weathering

​1. There are two types of weathering

​2. physical weathering is the process of breaking down rock without changing the composition of the rock.

​3.ex. a boulder rolling off a cliff can break apart, earthquakes causing faults, water freezing and thawing, forcing cracks apart

​4. plants and animals can also have an effect such as lichens breaking down rock.

Multiple Choice

_________ is the process of breaking down rock without changing the composition of the rock

• physical weathering

• chemical weathering

• fission

​Chemical weathering

​1. minerals can react with water, air, or substances in water and air

​2. chemical weathering is the process that changes the composition of rocks.

​3. some minerals can dissolve in slightly acidic water.

​4. others can react with the air and form new substances

​cont.

​5. chemical weathering happens faster in wet and/or warm conditions

​4. reactions happen faster in these conditions

​6. these reactions can form oxides, or clays

​7. chemical weathering happens more quickly to smaller pieces

Multiple Choice

___________ is the process that changes the composition of rocks

• physical weathering

• chemical weathering

• fission

Multiple Choice

chemical weathering happens more quickly with ______________ pieces of rock

• larger

• smaller

• fission

​Moving Earth Materials

​1. weathering produces smaller rocks

​2. erosion is the moving of weathered material or sediment form one location to another

​3. deposition is the laying down or settling of eroded material

​cont.

​1. gravity can cause large masses of rocks or soil downhill in a process called mass wasting

​2. erosion requires energy, this is provided by gravity in landslides

Multiple Choice

__________ is the downhill movement of a large mass of rocks or soil due to gravity

• erosion

• mass wasting

• fission

• chemical weathering

water erosion

​1. water causes most erosion

​2. the more water and faster it is flowing, the more sediment it can carry

​3. sediment is deposited downstream, at the inside bank, or when it enters another river, ocean or a lake

Multiple Choice

Water causes more erosion than other factors.  What type of water flow can carry the most sediment?

• fast moving

• slow moving

​wind erosion

• ​wind can slowly erode solid rock

• ​it can also puck up sand and move it

​Ice erosion

• ​large masses of ice formed by snow accumulation on land, that move slowly across Earth's surface are called glaciers

• ​these glaciers move downhill with gravity

• ​they carry large amounts of sediment and weather rocks underneath

​20,000 years ago

• ​glaciers covered the north half of North America

• ​they moved a lot of sediment and left it behind when they melted