EARTHQUAKES ANDVOLCANOES

By:

Muhammad Saghir(004)

Sumbal Zahid(013)

Ayesha Siddiqa(017)

Presented To:

“Miss. Huma Naeem”

WHAT IS AN EARTHQUAKE AND VOLCANO?

Moment of CrustRupture of Crust

FORMATION OF EARTHQUAKE

Two blocks of the earth suddenly slip past one another.

Terms related:• fault plane• hypocenter• epicenter • foreshock• mainshock• aftershocks

TYPES OF EARTHQUAKE

Three main types of fault that may cause an earthquake.

• Normal

• Reverse

• Strike-slip

Lithosphere of Earth is broken into plates

• Study of movement and interaction of plates:

Plate Tectonics• Zones of plate-edge

interactions are responsible for most earthquakes, volcanoes and mountains

• Divergence zones– Plates pull apart

during seafloor spreading

• Transform faults– Plates slide past

one another• Convergence zones

– Plates collide with one another

The tectonic plates of the world were mapped in the second half of the 20th century

•Ground shaking

•Tsunamis

•Landslides and Rockfalls

•Subsidence and lateral spreading

•Liquefaction

Earthquake Hazards

TSUNAMISTSUNAMIS CAN BE

GENERATED BY:

• Large Earthquakes

(megathrust events such as

Sumatra, Dec. 26, 2004)

• Underwater or near-surface

volcanic eruptions

(Krakatau, 1883)

• Large landslides that extend

into water (Lituya Bay, AK,

1958)

• Large undersea landslides

(evidence for prehistoric

undersea landslides in Hawaii

and off the east coast of North

America

The greater the viscosity the more gas in the magma. There are three basic types of magma:

Andesitic Magma

Rhyolitic Magma

Basaltic Magma

FORMATION OF VOLCANOES

Chemical composition (largely silica dioxide - sio2 - content)AndGas content (largely water vapor and co2).Sio2 content controls the viscosity of a magma.

MagmaType

ChemicalComposition

Temperature(degrees C)

Viscosity Gas Content

Basaltic

45-55% SiO2;

High in Fe, Mg, Ca; Low in K, Na.

1000 - 1200

Low Low

Andesitic

55-65% SiO2;

Intermediate Fe, Mg, Ca, Na, K

800-1000 Intermediate

Intermediate

Rhyolitic

65-75% SiO2;

Low in Fe, Mg, Ca; High in K, Na

650-800 High High

Large amounts of gas and a high viscosity (sticky) magma will form an explosive eruption Think about shaking a

carbonated drink and then releasing the cap.

Small amounts of gas and low viscosity (runny) magma will form an effusive eruption Where the magma just

trickles out of the volcano (lava flow).

TYPES (ON BASIS OF ERUPTION

3 States of Volcanoes:

 Extinct Volcanoes

e.g. Zuidwal volcano in the

Netherlands, Emperor

seamount chain in the Pacific

Ocean etc.

Dormant Volcanoes

e.g. Kilauea (Hawaii)

Mt. Etna (Italy)

Active Volcanoes

e.g. Mauna Loa etc.

Fourpeaked volcano, Alaska, in September 2007, after being thought extinct for over 10,000 years

Composite

Cinder Cone

Shield

• Tens of miles across and ten thousand or more feet in height.

• Tall cone shaped.• High in silica• High viscosity magma• High levels of gas• Highly explosive.• Formed by layers of lava and

ash.• Caused by viscous magma.

Actually, a mix of basaltic and rhyolitic magmas in many cases.Mt. Rainier, Washington

• After an eruption a large caldera

remains.

• Crater lake is a caldera that

remains following an explosive

eruption 7,700 years ago

• The eruption was 42 times more

powerful than Mt. St. Helens.

Mt. St. Helens, Washington

Mt. Fuji, Japan

• Huge in size

• A broad shaped, gently

sloping cone is formed,

but have low slopes.

• Flattened mound

• Resembles a warrior’s

shield.

• Low silica level.

• Dominated by fluid, high

temperature, low

viscosity basaltic

magma

• High or low levels of gas.

• No pyroclastic material.

This makes the eruption

relatively safer.

SHIELD VOLCANOS

Photograph by J.D. Griggs on January 10, 1985

Muana Loa Volcano – the world’s largest volcano.

• Over 30,000 feet above sea level.• Most active and planet's largest volcano

• Circular or oval cones.

• Range from several meters to over 300 m in height

• Small volcanoes.

• Structurally weak.

• Steep conical hill formed above a vent.

• Made from a pile of rock pieces

Mount Edziza, British Columbia• Dominated by viscous,

gaseous magmas.

• Relatively cool basaltic

magmas or andesitic

magmas predominate..

• Low silica lava

• “Fire-fountain” eruptions

• Commonly found on the

flanks of shield volcanoes

Floreana Island, Galapagos

Pu'u ka Pele, Hawaii(on the flanks of Mauna Loa)

Puu OO, Hawaii

Lava domes

• Lava is too viscous to

flow to a great

distance.

• Lava pile within.

• When a lava dome is

grown to a significant

extent, it shatters the

outer surface, which

results in spilling

loose fragments

towards its sides.

• Found on the flanks

of larger composite

volcanoes.

Volcanic Hazards

• Pyroclastic flow

• Lahars/Mud flows

• Pyroclastic fall

• Lava flow

• Ash flow

• Land sliding

• Noxious Gas

• Earthquakes

LAHARS

Water saturated slurry of

ash and other volcanic

debris that flows down

slope.

Pyroclastic Flow:

• A pyroclastic flow is a fast-

moving (up to 700 km/hr)

extremely hot (~1000°C)

mass of air and tephra that

charges down the sides of a

volcano during an

explosive eruption.

• Cinders.

• Ash and dust.

Pyroclastic flow at Mount St. Helens,

Washington, August 7, 1980.

Volcanic ash fall during mid-day with the eruption of Mount Pinatubo in the Philippines.

Pahoehoe: Lava with a ropelike surface texture due to partial cooling as the lava flowed. Relatively hot, low viscosity lava.

A hot, gaseous cloud of ash that flows down slope Flow speeds can reach 160 km/hr and temperatures can exceed 600 degrees C.

WORLD WIDE EARTHQUAKES AND VOLCANOES

Railway track disturbed by Earthquake.

• 2010 Chile earthquake. • Magnitude of 8.8.• Is at a convergent plate boundary that generates megathrust earthquakes.

Alaska Earthquake 1964

• Fault between

the pacific and

north

American

plates rupture

d.

•

• Shifts created

large tsunamis

 (up to 220

feet (67 m) in

height.

• Liquefaction.

   LossesThe number of deaths from the earthquake totalled 131; 115 in Alaska and 16 in Oregon and California.

Great East Japan Earthquake

• Magnitude 9.03• Undersea megathrust

earthquake off the coast of japan.

• The quake moved portions of northeastern japan by as much as 2.4 m (7.9 ft) closer to north America, making portions of japans' landmass wider than before.

Effect Of Earthquake On Tokyo Tower.

• Nuclear and conventional power plants went offline.

• 1000 aftershocks.• 15,882 deaths, 6,142

injured.• 129,225 buildings totally

collapsed, with a further 254,204 buildings 'half collapsed.

Mt. Fuji, Japan• A Stratovolcano that has erupted 16 times since 781 AD.• The most recent eruption was in 1707-1708•0.8 cubic km of ash, blocks, and bombs were ejected during that eruption.

• Just southeast of Hawaii is an undersea volcano known as loihi

• Until 1996 loihi was thought to be an inactive seamount.

• It began erupting in 1996 and the eruptions were preceded by a cluster of small earthquakes indicating the movement of magma.

• The modern active island rests close to the hot spot and its shield volcanoes are fed from the magma that the hot spot generates.

•

The Kilauea volcano erupted, with a fissure throwing lava up more than 20 meters towards the sky in a dazzling display of volcanic power

• Lava 65 feet in the air.

• Sulphur oxide and other volcanic gases are continuing to erupt .

• Kilauea is the youngest volcano in Hawaii and could be the world’s most active volcano and has erupted 34 times since 1952.

• Has been erupting consistently since January 1983.

Mount Pinatubo, Luzon, Philippines – 1991

• Stratovolcano.• Explosive eruption.• Ejected more than 1

cubic mile (5 cubic kilometers) of material into the air and created a column of ash that rose up 22 miles (35 km) in the atmosphere. Ash fell across the countryside, even piling up so much that some roofs collapsed under the weight.Nevado del Ruiz

Volcano, Colombia—1985

• Second most devastating volcanic eruption in the twentieth century.

• Result of a lahar.• An ice-cap volcano.• Ice melted and a huge flood. Boulders 32 feet-high still litter the

landscape around Nevada del Ruiz

NOVARUPTA, ALASKA PENINSULA – JUNE, 1912

• Largest volcanic blast of the 20th century

• The powerful eruption sent 3 cubic miles (12.5 cubic km) of magma and ash into the air, which fell to cover an area of 3,000 square miles (7,800 square km) in ash more than a foot deep.

• Caused global temperatures to drop by about 1 degree Fahrenheit (0.5 degree Celsius)

MOUNT ST. HELENS, USA—1980

• Large earthquake at 8:32 that morning measuring.

• 5.1 on the richter scale,

• of ash rose up to 15 miles into the atmosphere.

• $1 billion worth of damage to the lumber and agricultural industries.

Ash coming out of the Eyjafjallajkull Volcano in the recent eruption that created havoc in European airspace

Eyjafjallajkull Glacier

Eyjafjallajkull volcano

Iceland's Eyjafjoll Volcano:

• Iceland’s largest volcanoes

• A strato-volcano.

• Dormant beneath the Eyjafjoll

glacier.

• In year 1823, a fairly gentle

eruption with some local

flooding occurred

• European air travel was

severely disturbed

• Eruption began on march 20th

2010,

Earthquakes in Pakistan

• History has shown us

that Pakistan is indeed

situated near highly

active fault line that

could put risk to more

than 170 million people

living in the country.

1935 Balochistan Earthquake

• Magnitude of 7.7 • 30,000 and 60,000 people

died from the impact• Deadliest earthquakes that

hit South Asia.

Camps can be seen during the post-1935 earthquake.

• Magnitude of 7.2 rocked south-western Pakistan.

• At sparsely populated areas thus was not disastrous.

• Earthquake was felt in India, Iran, Bahrain, Afghanistan, Oman, Qatar and united Arab emirates. 2 women died due to this earthquake in Pakistan due to heart attack.

2011 Pakistan Earthquake

2005 Kashmir Earthquake

• Location: Muzafferabad, AJK• Magnitude 7.8• Saturday, October 08, 2005

at 08:52:37 AM• Distance: 105 km (65 miles)

NE of ISLAMABAD, Pakistan

• 73,000 people were killed and more than 3.3 million made homeless.

• Economic down fall.• Pak declared as failed state.

13th Deadliest Earthquake

Volcanoes of Pakistan:

Tor Zawar

• The only known volcanic activity in Pakistan was in January 2010.

• A small fissure eruption in the Ziarat region of west-central Pakistan produced a small lava flow in an area with no previous volcanic activity.

• Trachybasalt and  basaltic-andesite in composition.

Wednesday, February 03, 2010

Chandragup is a mud volcano located in Balochistan, Pakistan

    Malan Island is an offshore mud volcano located in theArabian Sea, 3 kilometers off the coast of Balochistan, Pakistan. It rose out of the water overnight in March 1999.

Jebel e Ghurab, is located in Balochistan, Pakistan. It is a mud volcano.

Neza e Sultan, is located in Chagai District, Balochistan, Pakistan. Neza e Sultan is an extinct volcano  and only the magma chamber remains and it looks like a spear.

This was All from the Presentation ……..

Thankyou