Environmental Geology

Chapter 12

EARTHQUAKES

EARTHQUAKES

Main content: about Earthquakes Why do earthquakes happen? Where do earthquakes happen? How do earthquakes happen and the outcome of Earthquakes? How to survive when earthquakes happen? How to avoid earthquakes and the way of predicting Conclusion ,References and related Websites

Part one

About Earthquakes Introduction

Earthquake Definition Earthquakes result from sudden slippage along fault zones. In response to stress . Most Earthquakes occur at boundaries and are related to plate-tectonics processes.

Example one

San Francisco

Example two Earthquake happens in Seoul ,South Korea From the picture ,Th e Overpass has been badly damaged by Earthquake

Example Three Earthquake jolts Tokyo from bed

A worker cleans up a floor scattered with CDs and videos at a rental video shop in Tsukuba, north of Tokyo Wednesday, Feb. 16, 2005. (AP Photo/Kyodo News)

Example Four Another earthquake shook San Francisco on October 17th, 1989. It was America’s second strongest earthquake and about 100 people were killed.

Example Five Massive Earthquake Kills 8,700 in Asia The world's most powerful earthquake in 40 years that hit Indonesia, has caused massive tidal waves in southeast Asia, which have killed at least 8,700 people.

Example six

A destructive earthquake struck Guatemala (危地 马拉）in February 1976, leaving parts of the city of Antigua Guatemala in ruins. Many buildings in the city and surrounding countryside have never been repaired.

Part one：Conclusion

From the above pictures, Hope you will generally grasp the idea of earthquakes from this narration. After the whole presentation ,you will gain a more thorough understanding of earthquakes and geology in general

Part seven：Conclusion

Let us come to the next part !

Part two Why do earthquakes happen ? Reasons:

The earth is formed of layers. The surface of the earth, is made of large pieces. When they move against each other, an earthquake occurs. A large movement causes a violent earthquake.

Six major plates consist of the whole earth surface

Part two Why do earthquakes happen? Scientists explain that the outside of the earth is made of a number of different plates. At San Francisco the Pacific plate which is moving towards the northwest meets the North American plate. The Pacific Plate is moving very slowly — at 5.3 centimeters a year. So San Francisco is the place where Earthquake occurs Frequently.

Part two

North

↖ West

•

American plate

Pacific plate

East

South

Part two Oceanic plate

Continent

★

★

Sometimes these two plates stop and do not move for years. Then Suddenly, they jump and an earthquake is felt. As a result of the movement of these plates, west America near the sea has always been a bad place for earthquakes. When the 1906 earthquake happened, the Pacific plate jumped 5-6 meters to the north.

Part two

Why do earhtquakes happen?

Next two pictures will give you a clear understanding

be made of plates

move(stop)...jump...felt…quake

Part two:summary Major earthquakes dramatically demonstrated that the earth is a dynamic,changing system . Earthquakes ,in general ,represent a release of built-up stress in the lithosphere . They occur along which Faults, in rock along which there is displacement of one side relative to the other . Sometimes,the stress produces new faults or breaks .

Part three Where do earthquakes happen? Places:

The locations of major Earthquake epicenters are concentrated in linear belts. These belts correspond to plate boundaries. Not all Earthquakes occur at plate boundaries . but most do.These areas are where plates jostle .

Part three The left map shows the places where major Earthquakes occur frequently and hugely .The red spots represent the places of the Earthquakes.

Part three For detail , I will give you some examples to support my idea that Earthquake epicenters are concentrated in linear belts.These belts correspond to plate boundaries.

Part three Example one: Earthquake hits Taiwan On the morning of

September 21th, 1999, another strong earthquake hit Taiwan province.

It happened in the centre of Taiwan province. About 2000 people died in the earthquake. the

number of people

who were hurt reached as many

as 4005.

Part three

Example two: Earthquake shakes Philippines

This is a VOA

news

A strong earthquake with a preliminary magnitude of 6.6 jolted southern Philippine provinces yesterday, panicking many people still celebrating the new year, officials said.

There were no immediate reports of damage or injuries, according to the Philippine Institute of Volcanology and Seismology.

Part three From the map listed on the right we know that Philippines is located on two plates boundaries.

Part three Example three: Strong Earthquake Hits Northeastern Japan

A strong earthquake with a Magnitude of 6.2 hit northeastern Japan 1998, the Japanese Meteorological Agency Saida strong earthquake shook an extensive area from the nation's northernmost island of Hokkaido to the northern part of Honshu, Japan's main island.

Part three The Asia plate

As we know , Japan is located on two plates boundaries. The Pacific plate

Part three:summary Earthquakes occur at plate boundaries ,actually most do. These areas are where plates jostle,collide with, or slide past each other,where relative plate movements may built up very large stresses ,Where major fault Or breaks may already exist on which further movement may occur . (On the other hand ,Massive Earthquakes certainly occur and may be quite severe, for reasons explored later in the related websites).

Continue !

Part Four The earth is a little blue planet. There always happen some disasters (灾祸) such as floods, volcanoes (火山)， and earthquakes …

Part Four Many people were killed in their cars, but a few lucky ones were not hurt.

Part Four Luckily the 1989 earthquake did not happen in the center of Tokyo but about 50 kilometers away. In one part of city a great many buildings were destroyed.

Part Four These buildings were over 50 years old, so they were not strong enough.

Part Four There were a lot of fires all over the city. The electricity was cut off for several days too.

Part Four A lot of cheap houses were destroyed. Only a few strong ones stayed up luckily. The city’s electricity supply was cut off at once.

A wide and busy road which was built like a bridge over another road fell onto the one below.

Part Four

Part Four

. The largest earthquake in China in 1976 . It happened in TangShang city HuBei province .After earthquake, Nothing were left to the city.

From the map listed on the right !

Part Four In 1976, the strong earthquake happened in Tangshan. Millions of people lost homes and a large number of buildings were destroyed.

Part Four After the earthquake, Because of shortage of houses ,The citizens of Tang Shan city had to live in the earthquake-proof houses which were constructed contemporarily

Part Four After rebuilding ,now, Tang Shan city gives us a fresh appearance !

Part Four:summary We cannot stop earthquakes, but we can do things to make sure they do not destroy whole cities. First, it is not a good idea to build houses along the lines where two of the earth’s plates join together. Second, if you think there may be an earthquake, it is better to build houses on rock not on sand. Third, you must make the houses as strong as possible. Weak buildings will fall down in an earthquake, but strong ones may stay up.

go

Part five How to survive when earthquakes happen? Would you know what to do during a really big earthquake? Experts have looked into the matter carefully. It may be worth you while to look over the following tips they have for us.

Part five: survival tips in earthquakes (1) If the ground begins shaking while you are driving,pull over and stay in your car. (2) If you are in a building,try to get near a strong wall. (3) The corner of a room or the speace behead the doorway is the safest. (4) As soon as the quake is over,check the gas pipe in the building.Gas fires often result from earthquakes. These tips may prove to be lifesavers. We should,therefor,keep them in mind.Remember always hope for the best but prepare for the worst.

Part five: survival tips in earthquakes Rumours are the biggest enemy in the emergent situation!

You are not supposed to believed the rumours!

Part five: survival tips in earthquakes Fix all your things firmly on the wall !

Publicise the earthquake-proof knowledge!

Part five: survival tips in earthquakes

The two pictures above show the ways of how to protect yourself at home when earthquake occurs!

Part five: survival tips in earthquakes

The two pictures show the ways of how to protect yourself in the open air when earthquake occurs!

Part five: survival tips in earthquakes After the earthquakes, We have the responsibility to reconstruct our hometown ! Not also for ourselves , but also for our motherland---China

Part five: survival tips in earthquakes

After the earthquake , there may be a lot of infective diseases and viruses , We should do some sanitatary work to prevent under the guide of professional nurses and doctors ! six

Part six: How to avoid earthquakes and the way of predicting To achieve the goals that avoid and predict the Earthquakes, some organizations have been founded . For example:

Asian Pacific Network of Centers for Earthquake Engineering Research (ANCER)

Part six: avoiding and predicting ANCER --Introduction Asian Pacific Network of Centers for Earthquake Engineering Research (ANCER) is Established. Asian Pacific Network of Centers for Earthquake Engineering Research (ANCER) has been founded in October 2001.

It is a unique international nonprofit, professional organization consisting of 7 national centers on earthquake engineering in the Asian-Pacific region.

Part six: avoiding and predicting ANCER --objective

The objective of ANCER is to coordinate limited resources in the respective countries to develop and implement, on a coop-erative, center-to-center basis, innovative engineering methods and new enabling technologies that are optimal to design, construct, maintain, manage and renew the built environment for reduced seismic hazard.

Part six: avoiding and predicting ANCER --effort To achieve its goal ANCER will pursue those activities as follows: 1) exchange of research plans; 2) exchange of data and information; networking of experimental facilities; 3) exchange of research personnel; 4) organize workshops and seminars; 5) promote cooperative research projects; 6) launch the publication of a high quality journal of international standards related to the smart structure technologies and earthquake and other natural disaster mitigation.

Part six: avoiding and predicting ANCER --effort example In year 2002,

ANCER will support an international conference on future challenges in earthquake engineering, to be held backto-back in Harbin and Hong Kong, China. ANCER plans to expand its membership during and after this conference. Currently

ANCER is headquarted at KEERC

Part six: avoiding and predicting For avoiding and predicting the Earthquakes better, some appliances have been invented . for example: Earthquake prediction sound_light alarm apparatus (Type DTE365) (HP inc.U.S.A)

Part six: avoiding and predicting Earthquake prediction sound_light alarm apparatus (Type DTE365) (HP inc. U.S.A)

Main functions:

Prediction alarm: This apparatus can sense earthquake advanced. It’s specific sensor is able to sense the vertical micro movement signal. Continuously detect, once earthquake occur the device will beep and flick before building wobble. It may produce warning signal advanced 30 seconds to 60 seconds before the earthquake happened.

Part six: avoiding and predicting Three kinds of alarm sound: three different sound express the variant progress of earthquake intensity.

The first warning alarm sound is 0 to 4 degree (adjustable), the second alert alarm sound is 1 to 7 degree(adjustable), the third danger alarm sound is 8 degree .

Part six: avoiding and predicting Diagnosis earthquake true or false: combine vibration acceleration, frequency and magnitude, compute and produce alarm signal during 3 seconds. The strong lightning stroke , explosive underground , or artificial corllide on occasion , these cases do not produce alarm signal. This device also sense the 2 to 3 degree earthquake 100 km far away.

Part six: avoiding and predicting

Exigent lighting : when earthquake happen and electricity supply closed , this device can supply several hours light or flicker sign to guide the people to leave quickly.

Part six: avoiding and predicting Properties: Battery type: 6V4AH Standy consumption: 1.2 mA

Magnitude error: 土0.25 degree Sensor: 10Hz detector

seven

Part seven: Conclusion ,References and related Websites (1) Conclusion Hope you will deeply grasp the idea of earthquakes from this presentation. After the listening, you will gain a more thorough understanding of earthquakes and geology in general and you will be able to find more information from my references and related Websites .

Part seven:

(1) Conclusion This presentation has gained a lot of help from my guider—professor Huan wen hui . Simply put , I will send my deep-hearted thanks and appreciations to Professor Huan wen hui .

(2) References Matthys Levy and Mario Salvadori(1995). (1st ed.). New York : Norton.

Martyn Bramwell (1994). . London : F. Watts.