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A landform is any
natural formation of
rock and dirt, found
on Earth. A
landform can be
as large as a
mountain range, or
as small as a hill.
“Geomorphological
feature”
U-shaped
Valley
V-shaped
Valley
Cave
Atoll
What is an arichpelago?
An archipelago is a chain or cluster of
islands. Archipelagos are usually
found in the open sea; less commonly,
a large land mass may neighbor them,
What is an ocean?
ocean* -- a great expanse of salt water.
What is an island?
• island -- a piece of land completely
surrounded by water
What is an atoll?
•
atoll - a ring (or partial ring) of coral that forms an island in an ocean or sea.
Typically, the volcanic mountain that rose up out of the sea was covered by
coral just off the shore of the island. As wind, rain, and other forms of
weather eroded the volcanic mountain, the coral would still grow at the
boundary between land and ocean. When erosion completely wiped out the
island, all that remains is the ring of coral around what used to be an island.
What is a cape?
• cape -- A point or head of land projecting
into a body of water
What is an isthmus?
• isthmus* -- a narrow strip of land, like a
bridge, connecting two larger strips of land
What is a bay?
• bay -- an area of sea partially enclosed by
land, smaller than a gulf
What is a beach?
•
•
A beach is a landform along the shoreline of a body of water. It usually consists of
loose particles which are often composed of rock, such as sand, gravel, shingle,
pebbles, or cobble. The particles of which the beach is composed can sometimes
instead have biological origins, such as shell fragments or coralline algae fragments.
Beaches often occur along coastal areas, where wave or current action deposits and
reworks sediments.
What is a sandbar?
•
A shoal or sandbar (also called sandbank) is a somewhat linear landform
within or extending into a body of water, typically composed of sand, silt or
small pebbles. A bar is characteristically long and narrow (linear) and
develops where a stream or ocean current promote deposition of granular
material, resulting in localized shallowing (shoaling) of the water. Bars can
appear in the sea, in a lake, or in a river.
What is a peninsula?
• peninsula* -- a narrow stretch of land
surrounded on three sides by water.
What is a sea?
sea* -- a relatively large body of water, either part of an ocean that is
partially surrounded by land (the Caribbean Sea), or a body of water that
is completely landlocked (the Caspian Sea is seen in the image above)
What is a sound?
• sound* -- a long passage of water
connecting two larger bodies
What is a river?
•A long body of water that flows across the
land.
•The Nile River is the longest river in the world
•The Amazon River is in Brazil.
•The Mississippi River is the longest river in
the United States.
What is a river source ?
• river source - beginning of a river
What is a river mouth ?
• river mouth -- the place where a river
empties into a larger body of water
What is a delta?
• delta -- a place at the river's mouth, where
the river splits into many different sections,
forming a marshy triangle
What is a tributary?
• tributary* -- A stream that flows into a
larger stream or other body of water
What is a flood plain ?
• flood plain -- A plain bordering a river and
subject to flooding.
What is a pond?
• pond is a body of water smaller than a
lake.
What is a gulf?
• gulf* -- A large area of a sea or ocean
partially enclosed by land
What is a strait?
• strait -- A narrow channel of water joining
two larger bodies of water (usually
narrower than a sound).
What is a marsh?
• marsh -- An area of soft, wet, low-lying
land, with grassy vegetation, often forming
a transition zone between water and land.
What is a swamp?
• swamp -- A lowland region
saturated with water.
What is a lake?
• lake* -- A large inland body of fresh water
or salt water
What is an oxbow lake ?
• An oxbow lake is a U-shaped lake water body formed
when a wide meander from the mainstream of a river is
cut off to create a lake. This landform is called an oxbow
lake for the distinctive curved shape that results from this
process.
What is meander?
• meander in general is a bend in a sinuous
watercourse, also known as an oxbow
loop, or simply an oxbow.
What is a basin?
basin* -- A large, bowl-shaped depression in the surface of
the land, often drained by a single river
What is a glacier?
• glacier -- A huge mass of ice slowly
flowing over a land mass
What is a moraine?
• moraine* -- An accumulation of boulders,
stones, or other debris carried and
deposited by a glacier
What is a fjord?
• fjord - a long, narrow sea inlet that is
bordered by steep cliffs
What is a plain?
• Plains are broad, nearly level stretches of
land that have no great changes in
elevation. Plains are generally lower than
the land around them; they may be found
along a coast or inland.
What is a steppe?
• steppe -- A vast grass-covered plain.
What is a dune?
• dune is a hill or a ridge made of sand.
Dunes are shaped by the wind, and
change all the time.
What is a alluvial fan ?
• An alluvial fan is a fan-shaped deposit formed where a
fast flowing stream flattens, slows, and spreads typically
at the exit of a canyon onto a flatter plain.
What is an oasis?
• oasis -- A fertile or green spot in a desert
or wasteland
What is a hill?
• hill* -- a small elevation in the earth's
surface
What is a cave?
• cave -- simply a hole in the ground, most
commonly in a rock that is porous and
readily eroded from within.
What is a butte?
A butte is an isolated hill with steep, often
vertical sides and a small flat top, smaller
than mesas, plateaus, and tables.
What is a canyon?
• canyon -- A
narrow chasm
with steep cliff
walls, cut into
the earth by
running water
What is a mesa?
• mesa -- A broad, flat-topped elevation with
one or more clifflike sides
What is a plateau?
plateau -- an elevated level expanse of land; a tableland.
What is a U-shaped valley?
A valley carved by glaciers, or glacial valley, is normally Ushaped. The valley becomes visible upon the recession of
the glacier that forms it. When the ice recedes or thaws, the
valley remains, often littered with small boulders that were
transported within the ice. Floor gradient does not affect the
valley's shape, it is the glacier's size that does. Continuously
flowing glaciers - especially in the ice age - and large sized
glaciers carve wide, deep incised valleys.
What is a V-shaped valley?
A valley formed by flowing water, or river valley, is usually Vshaped. The exact shape will depend on the characteristics of the
stream flowing through it. Rivers with steep gradients, as in
mountain ranges, produce steep walls and a narrow bottom.
Shallower slopes may produce broader and gentler valleys, but in
the lowest stretch of a river, where it approaches its base level, it
begins to deposit sediment and the valley bottom becomes a
floodplain.
What is a continental divide ?
A continental divide is a line of elevated terrain which forms a
border between two watersheds such that water falling on one
side of the line eventually travels to one ocean or body of water,
and water on the other side travels to another, generally on the
opposite side of the continent.
What is a mountain?
• The highest kind of land. They are caused when
two tectonic places collided.
• Types of mountains: Folded, Unwarped, & FaultBlock
What are Folded Mountains ?
Folded Mountains are made from rock layers that were
squeezed from opposite sides causing the rock layers to fold
What are Unwarped Mountains ?
Unwarped Mountains are made when the crust was pushed
upward by forces inside the Earth
What are Fault-Block Mountains ?
Fault-Block Mountains are made of huge tilted blocks of rocks that
are separated from surrounding rocks by faults. A fault is a huge
crack in the rocks.
What is a volcano?
volcano -- An opening in the earth's crust through which molten lava,
ash, and gases are ejected. Types of volcanoes: Shield, Strato, Dome,
Cinder Cone, and Rhyolite Caldera Complex
Shield Volcano
• Shield Volcano - A gently-sloping volcano that emits
mostly basaltic lava (very fluid lava) that flows in longlasting, relatively gentle eruptions - explosions are
minimal. Shield volcanoes can be very big
Composite or Strato Volcano
• Composite or Strato Volcano - A steep-coned volcano that
explosively emits gases, ash, pumice, and a small amount of stiff,
silica lava (called rhyolite). This type of volcano can have eruptions
accompanied by lahars -- deadly mudflows. Most volcanoes on
Earth are of this type. Stratovolcanoes kill more people than any
other type of volcanoes - this is because of their abundance on
Earth and their powerful mudflows
Lava Dome Volcano
• Lava Dome - A bulbous (rounded)
volcano that forms when very viscous lava
barely flows
Cinder Cone Volcano
• Cinder Cone - A cone-shaped volcano whose steep
sides are formed by loose, fragmented cinders that fall to
the Earth close to the vent. The lava flows through a
single vent that is usually only up to about 1,000 feet tall.
There is usually a bowl-shaped crater at the top. As the
gas-filled lava erupts into the air, the lava fragments into
pieces and forms cinders.
Rhyolite Caldera Complex
Volcano
• Rhyolite Caldera Complex - these are the most
explosive volcanoes. They do not look like
common volcanoes -- after an eruption, the
result is a caldera (crater) caused when the area
around the vent collapses.