Earth's Crust

20 5

Earth's crust is about ___ miles thick under the surface of the continents and __ miles thick under the ocean floor

core

Earth's innermost layer

crust

Earth's outermost layer

meteorites

Earth's surfaced is changed when it is hit by _____________ from space

push-pull

P waves are _________ waves that cause back and forth vibrations (like pushing and pulling on a slinky)

earthquakes

____________ are common along transform fault boundaries mountains can form here also

95

about ___% of all earthquakes occur at or near the edges of moving plates, along the great cracks in Earth's crust called faults

reabsorbed

as new crust is formed along divergent boundaries, old crust must be ___________ if not, Earth's crust would keep growing since the size hasn't changed, we know old crust is being reabsorbed

centimeters

as the asthenosphere flows, the plates above it are in constant motion the motion of the plates is so small (only a few ____________ a year) that we can't feel it only measurements detect it

opposite

at a transform fault boundary, 2 plates move past each other in __________ directions

hypothesize waves volcano

below the crust scientists can only _____________ about what the layers are made of they base them on patterns of _______ that travel through the Earth after an earthquake an on material that travels to the surface after an active __________

convergent boundary

boundary where crustal plates collide with each other

transform fault boundary

boundary where crustal plates grind past each other

divergent boundary

boundary where crustal plates move away from each other

Ring of Fire

chain of volcanoes nearly 30,000 miles long that almost completely surrounds the Pacific Ocean

move

continents and oceans are on plates because the plates ______, the continents we live on today looked different in the past and will look different in the future

lithosphere

cool and rigid portion of Earth

lithosphere

cool, solid portion of Earth that includes all of the crust and part of the upper mantle

rift

deep ocean valley formed where two crustal plates move apart

deposition

dropping of sediment from wind or water that slows down or from ice that melts

200

each year about _____ earthquakes around the world are large enough to cause major damage most are so small that people don't notice them

surface wave

energy wave from an earthquake that travels only at surface and moves less quickly that P and S waves but makes ground roll and sway

19,000

every year, about __________ meteorites fall to Earth (most aren't noticed because they are so small)

convection current

heat from Earth's center causes currents in the asthenosphere warm liquid rock in the mantle rises, then cools and sinks, warms and rises again, etc. this process of sinking and warming and rising and cooling is called a _______________

4000

how many miles is it from Earth's surface to the center of the Earth

glaciers

huge sheets of ice that change the surface of Earth

crumple fold mountain ranges

in a continental and continental collision, the plates ______ and ______ the collision forms ________________________

oceanic mountains volcanoes

in an oceanic and continental collision, the __________ plate is pushed down because it is denser this collision can form ___________ and _____________

pushed deep-ocean trench

in an oceanic and oceanic collision, one of the plates is ________ down under the other the plate that is pushed down melts this collision causes a _______________ to form

core

innermost layer of Earth's crust

mantle

layer directly beneath Earth's crust

mantle

layer of Earth's crust under the outermost layer called the crust

crust

magma melts the crust and oozes onto the surface, creating new _______

volcano

mountain that may form around an opening in Earth's surface where an eruption of molten rock occurs

erosion

movement or transportation of sediment to new locations

iron nickel

name the 2 things the inner core of is mostly made up of

crust mantle core

name the 3 layers of Earth's crust

oceanic and oceanic continental and continental oceanic and continental

name the 3 types of convergent boundary collisions

7200 * F

name the bottom of the mantle's temperature in degrees fahrenheit

7

name the number of major plates the lithosphere divided into all of Earth's land and oceans are on these plates

2

name the number of waves that travel inside Earth

mid-ocean ridge

name the place where most divergent boundaries are formed along

crust

name the thinnest of all of the Earth's layers

2900 * F

name the top of the mantle's temperature in degrees fahrenheit

oceanic

name the type of crust most transform fault boundaries are found in

crust

outermost layer of Earth's crust

mountains

plates move around the world forming ___________ and causing earthquakes and volcanic eruptions

focus

point in Earth's crust where first major movement of an earthquake fault occurs

epicenter

point on Earth's surface directly above focus of an earthquake

P wave

primary wave or "push-pull" wave of released energy in Earth's surface that causes a back-and-forth vibration in same direction that wind moves

sea-floor spreading

process in which magma is slowly pushed up through cracks in a rift and then cools to form new sea floor

plasticity

property of the asthenosphere which means it can flow

granite basalt

samples show that the continent is made of _________, but the crust under the oceans is made of denser ________

Richter scale

scale that measures amount of energy released during and earthquake

magnitude intensity

scientists can measure many aspects of an earthquake: __________ (amount of energy released) and _________ (amount of damage done)

inside at the surface

scientists have classified two wave types: those that travel ______ Earth and those that travel __________________

1

scientists have detected that there are about __ million earthquakes all over the world each year

magma

scientists hypothesize that divergent boundaries are caused by _______ being pushed upward under a plate

S wave

slower kind of energy wave released by an earthquake that causes vibrations at right angles to wave's direction of travel

hot spot move chain of volcanoes Hawaiin

sometimes volcanoes occur at a _______, a place on Earth where a column of molten magma pushes its way up to the crust a hot spot doesn't ______, but the plate above it does, forming a _____________________ the ________ islands were formed from a hot spot

earthquake

sudden movement of rock along a fault which releases energy vibrations

damage

surface waves are the chief cause of _________ during an earthquake

slower

surface waves travel only at the surface and travel ________ than S waves and P waves these powerful waves make the ground roll and sway

asthenosphere plasticity

the 7 major plates of the lithosphere float on the _____________ the huge stiff plates float because the asthenosphere has a property called _________

Ring of Fire

the Andes is a part of the ___________

Mercalli moment magnitude scale

the ________ intensity scale measures the amount of damage done from an earthquake the newer, more accurate scale scientists have recently begun using to measure the overall strength of earthquakes is called the __________________

Richter

the _________ scale measures the amount of energy released or magnitude

lithosphere

the ___________ floats on the asthenosphere and includes all of the crust and part of the upper mantle

lithosphere

the _______________'s plates fit together like a puzzle

newer older

the crust under oceans is ______ and thinner Oceanic crust the crust at the continents is ________ and thicker Continental crust

waves

the energy released from an earthquake travels away from the focus in _______

10,000

the inner core is extremely hot it's temperature is estimated to be more than ________ * F at this temperature, metals should melt

solid

the inner core is pressed into a ______ by the weight of all of the layers above

9.5

the largest earthquake ever recorded on Earth was ____ and occurred in Valdivia, Chile on May 22, 1960

liquid

the outer core is ______ metals of iron and nickel

continental drift

theory by Wegener that all continents were once joined together and then split apart

plate tectonics

theory scientists use to explain movements of plates on Earth's surface

primary

there are 2 kinds of waves that travel inside Earth the faster kind is called a _________ wave, or P wave the slower kind is called a secondary wave, or S wave

600 land 80

there are nearly ____ volcanoes on land volcanoes are the chief _____ builders scientists estimate that ___% of the area of the continents and ocean floors were formed by volcanoes

80 90

there is lots of activity along convergent boundaries ___% of all volcanoes and ___% of all earthquakes occur along this boundary type

drills

to get information about Earth's layers scientists use tools and instruments name the tool they use to get information about the crust they use the tool for taking samples of the crust

rocks volcanoes earthquake

using clues from ______, _________, and _____________ patterns, scientists have formed a hypothesis about how Earth's surface has changed over the past 500 million years

sea-floor spreading

what is it called when magma pushes up through the crust and pushes the old seafloor away and forms new crust

Alfred Wegener

what was the name of the scientist who determined that long ago, all the continents were joined together into one supercontinent known as Pangea he determined this by fitting all 7 continents together like puzzle pieces

speeds

when an earthquake occurs, it produces different kinds of waves that travel at different ________

convergent

where is old crust absorbed at

asthenosphere

zone of partially melted rock in upper mantle of Earth

asthenosphere

zone of weak and easily deformed rock in the upper mantle

erosion deposition

2 processes that change Earth's surface

right

S waves cause vibrations _______ angles to the waves direction of travel (like waves that travel on a rope that is shaken up and down)