Transcript Changes to Earth`s Surface

Changes to Earth’s Surface
Chapter C1
Changing Landforms
Earth’s ________ is always changing
due to _______, ________,
_________, ________, and _________
Earth’s ________, physical features on
its surface always ________ over time
Most changes to Earth’s surface
happen so ________ that you cannot
_______ them directly
Water
The shaping of landforms starts when _______ wears away rock
Weathering is the process of breaking rock into _____, sand and other
tiny pieces, or particles, called __________
Water is an important agent, or _______, of weathering
Fast-flowing ________, ________ waves, and ________ weather
rocks
After weathering has broken rock into sediment, _________ and
__________ move the sediment around and leave it in new places
__________ moves the sediment from one place to another and
__________ is the process of dropping sediment in a new location
Water is also the chief agent of ________ in the form of
________, _________, and __________
Most rivers deposit _________ in flat areas along their banks
and they an become rich _____________ areas
Wind
Wind is another form of _________ and _________
Wind can carry bits of _______ and ______ that
weather rock surfaces
Wind can also move _________ from place to place,
helping to ________ it
Wind erodes ______ sediment more easily than it
erodes soil or _______ rock
Wind erosion can blow sand into large mounds
called ________ and beach dunes can help
________ the land behind them during storms
Ice
Ice in the form of _______, which are thick sheets of ice, can
also change landforms
Glaciers are ________ sheets of ice and because of their great
size and weight they _______ everything underneath them
Glaciers erode _________ from one place and _______ it in
another
The two kinds of glaciers are ________ and _____________
Valley glaciers flow slowly down _______________, eroding
the mountain under them and forming U-shaped __________
____________ glaciers are ice sheets that cover large areas of
Earth and cover almost all of Greenland and ____________
Mass Movement
A ________ is one type of mass movement
Mass movement is the _________ movement of rock and soil because
of _______ and can change landforms ________
________ move wet soil and ________ move dry soil
Landslides occur when _________ becomes stronger than the
_________ that holds soil in place on a hill, causing soil to fall
suddenly to the bottom of a hill
A mass movement that occurs slowly is called ________ and
occurs when soil moves ________ downhill because of gravity
Creep may move the land only a few centimeters each
_______ but over time can move fences, roads and utility
poles
A sinkhole is a large _______ in the ground that opens
__________ and form after _______ under the surface has
dissolved or become weak
Sinkholes often appear in areas of _________ rock since it
dissolves easily and can cause the land to collapse
New Landforms
Erosion and deposition can _______ landforms or
______ new ones
Rivers can deposit _________ that builds _______
_________ are major forces for forming new landforms
When the glaciers melted, they left behind at their lower
ends long ridges of rock and soil, called _________
__________
New islands can be formed by _________ eruptions
__________ volcanoes increase their height by
depositing melted rock and ash and eventually break
through the sea surface as __________
Earth’s Interior
Earth is not a solid ball of rock, but has ________ distinct layers
and we live on Earth’s _______
The ________ is the outer layer, and it is made of _______
The ________ is the layer of solid ______ just beneath the
Earth’s crust
The mantle is however _______ in texture due to its ______
temperature
The only way we can observe parts of the __________ are
when it reaches the Earth’s surface through ___________
The _________ is the center layer of Earth and it can be
divided into two parts: outer core of liquid, or molten, _______
and an inner core of solid _______
Even though the core is very hot, great __________ at the
center of the Earth keeps the inner core _________
Earth’s Crust Moves (#1)
Earth’s surface is not a single layer of ________ but is made up of
many ________
Plates are rigid blocks of _______ and upper ________ rock
There are ______ major plates make up Earth’s surface
Earth’s plates fit together like pieces of a ________ _______
The plates ________ on the soft rock of the __________
_________ and ________ within the Earth produce __________ in the
soft rock of the mantle
As the mantle moves, the _________ floating on it move slowly, too
Because plates are close to one another, the _________ of one
plate affects another
Some plates _______ together, some ______ apart, some
________ past each other all causing changes in Earth’s
_________
Earth’s Crust Moves (#2)
When plates collide, _______ is released and new
_______ are produced
On land, ________ rise and ________ erupt and on the
________ floor deep trenches form
As plates pull apart, ________ dotted with ________
develop and forms new sea floor at the ridges
The ______, or crack will one day result in the separation
of parts of continents
When plates scrape and slide past each other, they
________ Earth’s surface causing ____________
Mountain Formation (#1)
_________ are Earth’s highest landforms and form as the crust
______, ________ and _______ upward because of movement
of Earth’s plates
Most of the highest mountains form where ________
________ collide
As the plates push together, their edges _______ and ______
into mountains, and the _________, Earth’s highest mountain
range located in Asia, formed this way
At some places, continental and _______ plates collide and the
lighter ________ plate moves up and over the oceanic plate,
forming mountains
Some mountains form away from edges of plates, where
_______ from movement at the boundaries _______ a block of
rock upward seeming to rise from flat land around them
Mountain Formation (#2)
Plates that pull apart leaves _______ between them
and ________ can bubble up between the plates
Magma is a hot, soft ______ from Earth’s ________
Magma builds up along the _______, forming long
chains of ________ under the ocean and are called
____-_______ ridges
The Mid-Atlantic Ridge separates North American
and ________ plates in the north and South
American and _______ plates in the south
Volcanoes
Most volcanoes form at ________ boundaries and are
mountains formed by ______ and _____
_______ is magma that reaches Earth’s ________ and ______
is small pieces of hardened lava
Chains of volcanoes form where a __________ plate and an
_________ plate collide
The edge of the _______ plate pushes under the _______ plate
and the leading edge of the oceanic plate ________ as it sinks
deep into the _________
The melted rock becomes ________ that forces its way up
between the _______
Sometimes, volcanoes form in the _______ of plates, over
unusually hot columns of _______ as the magma melts a hole
in the plate and causes volcanic _________
Earthquakes
An earthquake is a shaking of the ground caused by the
sudden release of _______ in Earth’s ________
The energy released as _______ crush together, scrape past
each other, or bend along jagged ________ can cause great
damage
More than one ________ earthquakes occur each year and
many earthquakes occur along the boundaries of the ________
plate
Earthquakes also occur along _________ in the crust
Faults occur in the middle of a _________ where the forces
pressing on the Earth’s _________ have bent or broken it
An earthquake sends out _________ in the form of seismic
waves, which are like ________ that form on a pond when a
stone is tossed in