These slides are related to Geography

1. DEPT GEOGRAPHY SECOND SEMETER
SUBJECT DISASTER
PRESENTATION ALL ABOUT EARTHQUAKE
PRESENT BY HABIB SHAH
PRESENTED TO SIR SYED QASIM
UNIVERSITY OF BALOCHISTAN QUETTA

2. What is an Earthquake
 The sudden shaking , trembling and vibration of Earth
surface by sudden release of stress within the crust is
know as Earthquake.
 There are large earthquakes and small earthquakes.
Large earthquakes can take down buildings and cause
death and injury. While small Earthquake even
sometime do not fell.

3. Aftershocks
An aftershock is an earthquake that occurs after a
previous earthquake, the main shock. An aftershock is in the
same region of the main shock but always of a smaller
magnitude.

4. FOCUS AND EPICENTER
 Earthquake generated at a point within the crust that
is know as focus and the point on the Earth surface
vertically above the focus that is know as epicenter
of an Earthquake.
 The line joining places of equal Earthquake intensity
are know as seismic wave’s.

5. Seismic wave’s
 Seismic waves are waves of energy that travel through
the Earth's layers, and are a result of earthquakes,
volcanic eruptions, magma movement, large
landslides and large man-made explosions that give
out low-frequency acoustic energy.
 The shaking is the strongest near the epicenter that is
why the greatest amount of distraction is cause near
the epicenter as a way from the epicenter.

6. P , S AND SURFACE WAVE’S
 A wave is a vibration that transfers energy from one place
to another without transferring matter (solid, liquid or
gas). Light and sound both travel in this way.
 When P and S wave’s reach to the Earth surface it
convert into surface or long wave's which travel along
the Earth surface.
 The most violent and distraction is caused by long wave’s

7. What causes seismic waves?
 Seismic waves occur from actions within the
Earth's core, including breaking and splitting
rocks, explosions and volcanic eruptions.

8. Seismograph
 Seismographs record earthquakes. They record vibrations in
the Earth, and they can detect both large and small
earthquakes. Seismographs working together can also
pinpoint the location of an earthquake.

9. Causes of an Earthquake
 Volcanic eruption exert a great pressure and earthquake occurs
in adjoining area. There is a deep relationship of causes and
effect between these two phenomena, often earthquake occur
at the time of volcanic eruption and sometimes earthquake
cause volcanic eruption.
 Plate tectonic
 Earthquake are mostly caused by tectonic forces. The greatest
intensity of seismic wave’s activity is found along convergent
plate boundaries where oceanic plate are undergoing
subduction. Strong pressure built up between the contact of
the two plate and these are release by sudden fault slippage.
that generate earthquake of large magnitude. The greatest
earthquake expressing in japan, Alaska, Central America chili
and other narrow zone else trenches and volcanic areas of
pacific belt.

10. Effects of an Earthquake
 Landslide Earthquakes, along with severe storms, volcanic
activity, and coastal wave attack, and wildfires, can produce
slope instability leading to landslides, a major geological
hazard. Landslide danger may persist while emergency
personnel are attempting rescue.
 Fire Earthquakes can cause fires by damaging electrical
power or gas lines. In the event of water mains rupturing
and a loss of pressure, it may also become difficult to stop
the spread of a fire once it has started. For example, more
deaths in the 1906 San Francisco earthquake were caused
by fire than by the earthquake itself.

11. Effects
 Flood A flood is an overflow of any amount of water that
reaches land. Floods occur usually when the volume of water
within a body of water, such as a river or lake, exceeds the
total capacity of the formation, and as a result some of the
water flows or sits outside of the normal perimeter of the
body.
 However, floods may be secondary effects of earthquakes, if
dams are damaged. Earthquakes may cause landslips to dam
rivers, which collapse and cause flood.

12. Effects
 Tsunamis A tsunami is a large ocean wave that is caused by
sudden motion on the ocean floor. This sudden motion could be an
earthquake, a powerful volcanic eruption, or an underwater
landslide.
 The impact of a large meteorite could also cause a tsunami.
Tsunamis travel across the open ocean at great speeds and build into
large deadly waves in the shallow water of a shoreline.

13. Human impacts
 An earthquake may cause injury and loss of life, road and bridge
damage, general property damage, and collapse of buildings. The
aftermath may bring disease, lack of basic necessities, mental
consequences such as panic attacks, depression to survivors, and
higher insurance premiums.

14. MAJOR EARTHQUAKE
 One of the most devastating earthquakes in recorded
history was the 1556 Shaanxi earthquake, which occurred
on 23 January 1556 in Shaanxi province, China. More than
830,000 people died. Most houses in the area were
destroyed and many victims were killed when these
structures collapsed. The 1976 Tangshan earthquake, which
killed between 240,000 and 655,000 people, was the
deadliest of the 20th century.
 The 1960 Chilean earthquake is the largest earthquake that
has been measured on a seismograph, reaching 9.5
magnitude on 22 May 1960. Its epicenter was near Canter,
Chile

15. Earthquakes events in recent time.
 The greatest earthquake in history occurred in Chile, 1960 May 22 . It had a magnitude of
9.5 and approximately 1,655 were killed, 3,000 injured, 2,000,000 homeless, and $550
million damage in southern Chile.
 On Tuesday, January 12, 2010, another earthquake measuring 7.0 with an epicenter 16
miles west of Port-au-Prince, Haiti struck, killing over 100,000 people and affecting over 3
million others.
 An earthquake of magnitude 7.7 struck southwest Pakistan on Tuesday, 24th September
2013, killing more than 327 and injuring hundreds more. Reports indicated that houses
were flattened
 1935 Quetta earthquake. The 1935 Quetta earthquake occurred on 31 May between 2:33
am and 3:40 am at Quetta, Baluchistan, British Raj (now part of Pakistan). The earthquake
had a magnitude of 7.7 Mw and anywhere between 30,000 and 60,000 people died from
the impact.

16. Preparing for an Earthquake
Government
 Authorities need to educate people about earthquake prone
areas and fault lines in the country. People must also be
educated about what earthquakes are and how to respond
to them when they occur.
 Proper building permits and approvals must be given before
people build in these areas.
 Governments must ensure, schools and shelters, and
emergency command that facilities like fire and police
stations, hospitals posts are working well and prepared to
deal with an emergency. . In many countries, these facilities
are legal requirements.

17. Preparing for an Earthquake
 Individual
 Know your environments and buildings. It is important that you know where you live and
where you visit often. If this is an earthquake prone region, be sure you know about your
building (home, school, work places) always keep in mind what you can do if an
earthquake starts.
 During an earthquake, try to get away from objects that will fall or break. Run for cover
under a sturdy piece of furniture.
 Move into the open if this is possible. Go out of the building if possible, as the building
can cave in.

18. THE END