Transcript surface features - Doral Academy Preparatory

SURFACE FEATURES OF
THE EARTH
MOUNTAINS
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Fold Mountains
Fold mountains are the most common type of mountain. The world’s largest mountain
ranges are fold mountains. These ranges were formed over millions of years. Fold
mountains are formed when two plates collide head on, and their edges crumbled,
much the same way as a piece of paper folds when pushed together.
Fault-block Mountains
These mountains form when faults or cracks in the earth's crust force some materials
or blocks of rock up and others down.
Dome Mountains
Dome mountains are the result of a great amount of melted rock (magma) pushing its
way up under the earth crust. Without actually erupting onto the surface, At some
point, the magma cools and forms hardened rock. The uplifted area created by rising
magma is called a dome because of looking like the top half of a sphere
Volcanic Mountains
Volcanic Mountains are formed when molten rock (magma) deep within the earth,
erupts, and piles upon the surface. Magna is called lava when it breaks through the
earth's crust. When the ash and lava cools, it builds a cone of rock.
Plateau Mountains (Erosion Mountains)
Plateau mountains are not formed by internal activity. Instead, these mountains are
formed by erosion. Plateaus are large flat areas that have been pushed above sea
level by forces within the Earth, or have been formed by layers of lava.
World Famous Mountains Top 10
List:
Mountain Name
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Mount Everest
K2 Mountain
Kanchenjunga Mountain
Lhotse Mountain
Makalu Mountain
McKinley Mountain
Kilimanjaro Mountain
Ranier Mountain
Country
Nepal-Tibet
Kashmir
India-Nepal
Nepal-Tibet
Nepal-Tibet
United States
Tanzania
United States
Height
First climbed
29,028
28,250
28,208
27,923
27,824
20,320
19,340
14,410
1953
1954
1955
1956
1955
1913
1889
1870
VOLCANOES
There are four kinds of volcanoes that have been discovered on earth:
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The shield volcano: This volcano is formed from fluid basaltic magma. The
explosions made by this volcano are generally less violent than those of
other volcanoes. These volcanoes are generally also smaller and flatter
than other volcanoes.
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The cinder cone: These volcanoes are formed by basaltic and andesitic
magma, and they are named cinder cones because they blow ash into the
sky. Eruptions from these volcanoes tend to contain a lot of gas.
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The dome: This is a shorter, rounder volcano formed by viscous dacite
magma. This volcano has smaller eruptions but more lava flow than the
typical volcano.
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The stratovolcano: This volcano is the most dangerous kind, due to its huge
size and height. Formed by andesite and dacite lava, this volcano tends to
be extremely dangerous. Firestorms, mud flows and pyroclastic flows are all
caused by this type of volcano.
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The caldera: This is a generally dry, extinct volcano formed near or in water.
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Mount Vesuvius, Italy
• Mount Vesuvius is considered
one of the most dangerous
volcanoes. The eruption of 79
AD destroyed the cities of
Pompeii and Herculaneum.
The subsequent eruptions
have been less severe. It
poses many threats to the
large population in its vicinity.
This makes it a volcano to
watch out for.
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Krakatau, Indonesia
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Among the 130 active volcanoes
in Indonesia, Krakatau is the most
famous because of its explosive
eruptions. In terms of size, it is not
one of the largest volcanoes. It
showcased its might in an 1883
explosion, which resulted in the
disintegration of the northern
portion of the island. This later
caused many tsunamis. Nearly
36,000 individuals lost their lives
due to the massive walls of water.
EARTHQUAKES
• An earthquake is a vibration that travels
through the earth's crust.
• We only hear about earthquakes in the news
every once in a while, but they are actually an
everyday occurrence on our planet. According to
the United States Geological Survey, more than
three million earthquakes occur every year.
That's about 8,000 a day, or one every 11
seconds!
• The Richter Scale is used to rate the
magnitude of an earthquake -- the
amount of energy it released.
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MAJOR QUAKES THUS FAR IN
2010:
• January 3, 2010
• January 10, 2010
• January 12, 2010
• February 27, 2010
• March 5, 2010
• April 4, 2010
• April 6, 2010
• April 11, 2010
• April 11, 2010
• April 13, 2010
Solomon Islands
Offshore N. California
Haiti
Chile
Sumatra, Indonesia
Baja California, Mexico
Northern Sumatra
Solomon Islands
Spain
China
Magnitude 7.2
Magnitude 6.5
Magnitude 7.0
Magnitude 8.8
Magnitude 6.5
Magnitude 7.2
Magnitude 7.7
Magnitude 6.8
Magnitude 6.3
Magnitude 6.9
TSUNAMI
• A tsunami is a series of water waves caused by the
displacement of a large volume of a body of water.
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Earthquakes, volcanic eruptions and other underwater
explosions, all have the potential to generate a tsunami.
• Tsunamis have a small amplitude (wave height) offshore,
and a very long wavelength which is why they generally
pass unnoticed at sea, forming only a slight swell usually
about 12 in above the normal sea surface. They grow in
height when they reach shallower water
December 26th 2004
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2004, Indian Ocean –
A recent major earthquake rumbled deep on the floor of the Indian Ocean
on December 26, 2004. At an estimated magnitude of 9.3, it was the second
strongest quake ever recorded by seismologists. Occurring more than 18
miles beneath the ocean, the quake itself was not particularly devastating.
Lives were lost and property was damaged in the quake, but because of
events that followed there is no reliable estimate of how many or how much.
While the quake itself may have caused some damage, the resulting
seismic tidal wave it created was legendary. The Indian Ocean Tsunami
struck dozens of countries, including parts of India, Indonesia, Thailand, and
Sri Lanka. Waves measuring between 80 and 100 feet high struck the
coastal areas. The force of the waves carried them more than a mile inland,
in some areas. Thousands of communities were destroyed, or displaced;
resort communities were drowned; coastlines were completely reshaped by
the force of the waters; and whole island populations are believed to have
perished. Between 175,000 and 250,00 are believed to have perished,
though a solid number may never be known, and no reliable estimate of
damages yet exists. The entire region was quickly declared a disaster area,
and the whole world offered aid.
Ultimately, the Indian Ocean Tsunami reached as far as South Africa to the
west and Mexico to the east of the quake epicenter. Every ocean,
worldwide, showed at least some measurable effect from the event. It is
without question the first great natural disaster of the 21st century.