Earthquake , Volcano and Tornado

Geography projectBy- ROUSHAN HARI

CLASS-8SCHOOL- St Francis Academy

INDEXTOPIC Page No.1. Earthquake

3 -26

2. Volcano 27-42

3. Tornado 43-53

A Tragedy To Life And Property

Introduction

Earthquakes constitute one of the worst natural hazards which often turn into disaster causing widespread destruction and loss to human life.

The effects of earthquake vary upon the magnitude and intensity. Earthquakes occur every now and then all round the world, except in some places where earthquakes occur rarely. The devastation of cities and towns is one of the effects of earthquake.

What is Earthquake?

An Earthquake is the result of a sudden release of energy in the earth’s crust that creates seismic waves.

The seismic activity of an area refers to the frequency , type and size of earthquakes experienced over a period of time

Causes Of Earthquake

The primary cause of an earthquake is faults on the crust of the earth.

“A Fault is a break or fracture b/w two blocks of rocks in response to stress.”

This movement may occur rapidly, in the form of an earthquake or may occur slowly, in the form of creep.

Earth scientists use the angle of the fault with respect to the surface (known as the dip) and the direction of slip along the fault to classify faults.

Some major causes of earthquakes on basic of its causes are:

Surface causes

Volcanic causes

Tectonic causes

Surface cause:

Great explosions, landslides, slips on steep coasts, dashing of sea waves , avalanches , railway trains, heavy trucks, some large engineering projects cause minor tremors. some of them are man made, other are natural.

Strength Of EarthquakeThe intensity and strength of an earthquake is measured on Richter scale,the scale invented by Charles Richter California ,USA in 1935.which categories earthquake on the basis of energy released.Defintion:“the logarithm to base ten of the maximum seismic-wave amplitude recorded on a standard seismograph at a distance of 100 kilometres from the earthquake epicentre.”

Scientists measure the strength of earthquakes using machines known as seismographs.

Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth.

Seismometers-The measurement of earthquake

Seismometers are instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources.

Seismometers may be deployed at Earth's surface, in shallow vaults, in boreholes, or underwater.

Types Of Zones

Zone - II: This is said to be the least active seismic zone.

Zone - III: It is included in the moderate seismic zone.

Zone - IV: This is considered to be the high seismic zone.

Zone - V: It is the highest seismic zone.

 The earthquake zoning map of India divides India into 4 seismic zones Based on the observations of the affected area due to Earthquake india divided into four types of zones:

Earthquake PredictionEarthquake prediction is usually defined as the specification of the time , location , and magnitude of a future earthquake within stated limits.

But some evidence of upcoming Earthquake are following:

Unusual animal behaviorWater level in wellsLarge scale of fluctuation of oil flow from oil wellsForeshocks or minor shocks before major earthquakeTemperature changeUplifting of earth surfaceChange in seismic wave velocity

Loss of life and property

Damage to transport system i.e. roads, railways, highways,

airports, marine

Damage to infrastructure.

Chances of Floods – Develop cracks in Dams

Chances of fire short-circuit.

Communications such as telephone wires are damaged.

Water pipes, sewers are disrupted

Economic activities like agriculture, industry, trade and transport

are severely affected.

Consequences Of Earthquake

Earthquake Safety Rules

If you are in house;

• Don’t use lift for getting down from building.

• Be prepared to move with your family.

If you are in shop ,school or office;

• Don’t run for an exit.

•Take cover under a disk/table.

•Move away from window glass.

•Do not go near electric point and cable. Keep away from weak portion of

the building and false ceiling.

If you are outside;

• Avoid high buildings , walls , power lines and other objects

that could fall and create block.

• Don’t run through streets.

• If possible , move on to an open area away from hazard

including trees.

If you are in vehicle;

• Stop in a safe open place.

• Remain inside vehicle.

• Close window , doors and vents.

After An EarthquakeKeep calm, switch on the transistor radio and obey instructions.Keep away from beaches and low banks of river. A huge wave may sweep inDo not re enter badly damaged buildings and do not go near damage structures.Turn off the water, gas and electricity.Do not smoke, light match or use a cigarette lighterDo not turn on switches there may be gas leak or short circuitIf there is any fire, try to put it out or call fire brigade.

Cont..

Do not drink water from open containers without having examined it.

If you aware of people have been buried, tell the rescue team. Do not rush and try not to worsen the situation.

Avoid places where there are loose electric wires and do not come in contact with any metal object.

Eat something. You will better and more capable of helping other.

Do not walk around the streets to see what is happening. Keep the streets clear so rescue vehicles can access the roads easily.

Date Place Scale DamageSept 2, 1993

Latur (maharashtra)

6.3 Large areas of Maharashtra rocked. 10,000 people lost lives.

May 22, 1997

Jabalpur (Maharashtra)

6.0 40 person killed and over 100 injured.

March 29, 1999

Nandprayag 6.8 widespread destruction in chamoli , rudraprayag and other areas. Massive loss of human life.

Jan. 26, 2001

Bhuj (gujrat) 7.8 Tremors left by India and its neighboring countries. Over 1 lakh people killed. Huge loss to property and infrastructure.

April 25,2015

Nepal 7.8 Heavy damage to life and property.Death toll about 8000 and nearly 21000 injured

Picture Of Search And Rescue Phase Of Latur Earthquake 1993

Helpless man being trapped under debris

Damage to high rise building in Bhuj

Nepal Earthquake April 2015

VOLCANOESCannon of immense size

What is a volcano?

A volcano is a mountain where lava (hot, liquid rock) comes from a magma chamber under the ground. A volcano usually has a summit, a slope and base.

Most volcanoes have a volcanic crater at the top. When they are active, materials pour out of it. This includes lava, steam, gaseous compounds of sulphur, ash and broken rock pieces.

Volcanoes erupt when magma and pressure come together, and the pressure blows off the top of the solid rock, and the magma pours out.

Causes of volcanoes

There are two main causes. Volcanoes are made when two tectonic plates come

together. When these two plates meet, one of them (usually the oceanic plate) goes under the continental plate. This is the process of seductions. Afterwards, it melts and makes magma (inside the magma chamber), and the pressure builds up until the magma bursts through the Earth's crust.

The second way is when a tectonic plate moves over a hot spot in the Earth's crust. The hot spot works its way through the crust until it breaks through. The caldera of Yellowstone Park was formed in that way; so were the Hawaiian Islands.

Types of Volcanoes: SHIELD VOLCANOES

Shield volcanoes are built out of layers of lava from continual eruptions (without explosions). Because the lava is so fluid, it spreads out, often over a wide area. Shield volcanoes do not grow to a great height, and the layers of lava spread out to give the volcano gently sloping sides. Shield volcanoes can produce huge areas of basalt, which is usually what lava is when cooled.

Even though their sides are not very steep, shield volcanoes can be huge. Mauna Kea in Hawaii is the biggest mountain on Earth. If it is measured from its base on the floor of the sea, Mauna Kea is even taller than Mount Everest, the tallest mountain on land.

Classification of VolcanoesA traditional way to classify or identify volcanoes is by its pattern of eruptions. Those volcanoes which may erupt again at any time are called active. Those that are now quiet called dormant (inactive). Those volcanoes which have not erupted in historical times are called extinct.

ACTIVE VOLCANOES

An active volcano is currently erupting, or it has erupted in the last 10,000 years. An example of an active volcano is Mount St. Helens in the United States (US).

Mt. St. Helens, U.S.A.

DORMANT VOLCANOES

A dormant volcano is "sleeping," but it could awaken in the future. Mount Rainier in the United States is considered dormant

Mount Rainier, U.S.A.

EXTINCT VOLCANOES

An extinct volcano has not erupted in the past 10,000 years. Edinburgh Castle in Scotland is located atop an extinct volcano.

Edinburgh Castle , Scotland

Consequences of volcanoes Eruptions occurring close to human settlements may spill

and destroy lives and property. People often have to be evacuated.

Ash discharged very high into the stratosphere can have negative consequences on the ozone layer.

Landscapes and natural sceneries can be destroyed.

Ash and mud can mix with rain and melting snow, forming lahars. Lahars are mudflows flowing at very fast pace.

MT. MAUNA KEA, HAWAII

MT. FUJI, JAPAN

MT. KRAKATOA, HAWAII

In the eye of the tornado, there's no more high and

low, no floor and sky

TORNADO

A tornado is a violently rotating column of air that rotates while in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as twisters or cyclones, although the word cyclone is used in meteorology to name any closed low pressure circulation.

Tornadoes come in many shapes and sizes, but they are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds less than 110 miles per hour (180 km/h), are about 250 feet (80 m) across, and travel a few miles (several kilometers) before dissipating. The most extreme tornadoes can attain wind speeds of more than 300 miles per hour (480 km/h), are more than two miles (3 km) in diameter, and stay on the ground for dozens of miles (more than 100 km)

Introduction

A tornado is "a violently rotating column of air, in contact with the ground, either pendant from a cumuliform cloud or underneath a cumuliform cloud, and often (but not always) visible as a funnel cloud . For a vortex to be classified as a tornado, it must be in contact with both the ground and the cloud base. Scientists have not yet created a complete definition of the word; for example, there is disagreement as to whether separate touchdowns of the same funnel constitute separate tornadoes .Tornado refers to the vortex of wind, not the condensation cloud

What is Tornedo?

Tornadoes have been recorded on all continents except Antarctica and are most common in the middle latitudes where conditions are often favorable for convective storm development . The United States has the most tornadoes of any country, as well as the strongest and most violent tornadoes.

A large portion of these tornadoes form in an area of the central United States popularly known as Tornado Alley . Other areas of the world that have frequent tornadoes include significant portions of Europe, South Africa, Bangladesh, parts of Argentina, Uruguay, and southern Brazil, New Zealand, and far eastern Asia

Places where Tornedo takes place

Tornedo mapping of the world

Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability and (2) wind shear present in the lower atmosphere. 

Instability refers to unusually warm and humid conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere.  

This kind of wind shear and instability usually exists only ahead of a cold front and low pressure system. The intense spinning of a tornado is partly the result of the updrafts and downdrafts in the thunderstorm (caused by the unstable air) interacting with the wind shear, resulting in a tilting of the wind shear to form an upright tornado vortex.

Causes of Tornedo

Consequences of TornadoTornadoes effect the environment by destroying buildings and trees.

Tornadoes also kill animals, which effects the food chain and disrupts the whole environment.

Tornadoes destroy our farms, which means there will be food shortages around the surrounding area.

After everything is destroyed, humans have to rebuild. Tornadoes can cause water contamination, which poses a serious problem, as plants, animals and humans are effected by this.

Debris can be very dangerous, as it could kill plants and animals very easily. Some trees take over 100 years to grow, so if they are destroyed, they will be hard to replace. 

Fires may occur after a tornado due to damaged power lines and gas leaks.

Joplin tornado

Alabama Tornado

Date Place DamageApril 25-28, 2011

USA More than 200 tornadoes across Northern Mississippi, Central and Northern Alabama, Eastern Tennessee, Southwestern Virginia and Northern Georgia resulted in 316 deaths with property damage in excess of 4.2billion dollars.

Tuesday, April 29, 2014

Mississippi, USA

Tornado ripped through Townships in Arkansas and Mississippi killing at least 34 people. It also caused various degrees of injuries to 200 more people. The tornado measured F3 on the Enhanced Fujita Scale. More than 2,000 homes and 100 commercial properties were reported to be damaged.

Monday, November 18, 2013

Illinois, Indiana and Kentucky, USA

Powerful tornadoes, numbering about 30 swept through the US Midwest, killing about 8 and injuring many more. Many people were trapped in buildings. Winds up to about 68mph, carrying rain and hailstones as big as tennis balls caused massive damage to buildings and property. Entire communities were wiped away leaving nothing left.

Places Where Tornado Taken Place