Geological disasters

1. What is disaster
A sudden accident or a natural catastrophe that cause
great damage or loss of life.

2. What are geological disasters
A natural disaster due to geological disturbances,
often caused by shifts in tectonic plates and seismic
activity
Examples Earthquakes, landslide, volcanic eruptions,
avalanches

3. Contents
 Avalanches
Landslides
Earthquakes
Volcanic eruptions

4. Avalanches

5. What is avalanche
Large mass of rock debris or snow
that moves rapidly down a mountain
slope, sweeping and grinding
everything in its path.

6. How they are created
• An avalanche begins when a mass of material
overcomes frictional resistance of the sloping
surface, often after its foundation is loosened
by spring rains or is rapidly melted by warm, dry
wind. Vibrations caused by loud noises, such as
artillery, thunder, or blasting can create an
avalanche.
• Avalanches usually occur in February, March,
and January. They can also occur in April when
everything thaws.

7. Areas in the world where Avalanches
Occur
• Avalanches can occur anywhere in the world.
• They occur where ever there is a high snow
covered mountain.
• Avalanches can also occur near plate
boundaries. Usually at convergent plate
boundaries.

8. Damage Due to Avalanches
• Avalanches don’t do a lot of damage to cities
or towns because they are up in the high
mountains but anything up there better watch
out.
• Avalanches burry mountain side homes and
destroy forests. They also take down radio
towers and lodges that are in its path.
• Avalanches also take away people’s lives,
especially skiers who are taking a trip down
the mountain.

9. Tips on Avalanches
• If you are in an area that is highly at risk
for avalanches be sure not to ski or use any
snowmobiles on the mountain.
• Try not to use any explosives around an
avalanche zone.
• If there was a heavy snow fall the night
before make sure not to go on the mountain
because you might trigger an avalanche.
• Don’t ever go alone on a mountain that
has been known to have avalanches.

10. Future Research
• They are doing research to find out about
the mechanisms that govern the build-up of
snow - wind and precipitation - instability
within the snow cover, and the flow of
avalanches.
• The main objective of this research is to
improve zoning and make defenses more
effective and more reliable.

11. Landslide

12. What is landslide
A landslide is an catastrophic event
where a block of earthen mass slides
downhill.
Cause significant loss of life and
billions of dollars each year.

13. Landslides Prediction
Although a basic understanding of the
landslides is available, system that predict
the occurrence of a landslide do NOT exist.
Why?
The lack of field measurements over large
temporal and spatial scales.

14. How they occur
Natural causes of Landslides:
• Earthquakes: Seismic activities have always been a
main cause of landslides throughout the world. Any time
plate tectonics move the soil that covers them moves
with it. When earthquakes occur on areas with steep
slopes, many times the soil slips causing landslides.
• Heavy Rainfall: When sloped areas become completely
saturated by heavy rainfall many times landslides can
occur. Without the aid of mechanical root support the soil
simply runs off when it contains too much water.

15. Cont..
Human causes of Landslides:
• Clear Cutting: Method of timber harvesting which
completely removes all old growth timber from the area.
This method is hazardous because it destroys the existing
mechanical root structure in the area.
• Mining: Mining operations that use blasting techniques
often cause other areas that are at the risk of sliding to
slide due to vibrations under the soil.

16. Before the occurrence of landslide
(Prevention)
• In terms of economic aspects, the
government needs to upgrade more on
the knowledge on natural
phenomenon to the public through
media such as internet, seminar and
others. By stating more information
regarding the landslide, the locals
would know few things about landslide
and the way to deal with landslide if it
occurs. Not only that, the government
should provide more expertise to
prevent this matter before it happens.
In addition, with expertise help, the
government should held campaign for
the locals to participate. Therefore, the
locals can gain knowledge on this
matter.
• In term of social aspects, the locals
need to understand and apply their
knowledge about the occurrence of
landslide. The locals must aware
about their areas especially the area
that are near steep slopes, lose to
mountain edges, near drainage ways
or natural erosion valleys. As
mentioned earlier that the
government should provide
knowledge about landslide, the locals
should take precautious about their
property, such as the locals should
contact the expertise and as for
information their property that
whether their area are prone to
landslide or not.

17. After the occurrence of landslide
(Curing)
• In terms of economical
aspects, house owners
should choose housing
insurance companies that
can cover damages caused
by landslide if they feel that
their houses are prone to
landslide. This would ease
the burden of the victims in
financial terms.
• In terms of infrastructure
aspect, retaining walls
should be checked for
damages quite often to
ensure that it is properly
functioning. The
surrounding areas of the
retaining walls should also
be included in this
maintenance process. For
instance checking whether
the wall retentions' holes
are blocked or not.

18. Planning action
In this section, we were asked to plan
some actions regarding our projects.
The actions will be executed
individually and these are the action
plan that will be executed:
•Insurance coverage
•Creating a blog
•Plantation of trees

19. Recently we have seen an example of
landslide
KEDARNATH

23. Earthquake

24. 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

25. Cont…
For example:
If you throw stone in a pond of still water,
series of waves are produced on the surface
of water, these waves spread out in all
directions from the point where the stone
strikes the water. similarly, any sudden
disturbance in the earth’s crust may
produce vibration in the crust which travel
in all direction from point of disturbances.

26. 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 and the direction
of slip along the fault to classify faults.

27. Earthquake Prediction
• Unusual animal behavior
• Water level in wells
• Large scale of fluctuation of oil flow from
oil wells
• Foreshocks or minor shocks before major
earthquake
• Temperature change
• Uplifting of earth surface
• Change in seismic wave velocity

28. Effect Of Earthquake
• 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.

29. 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
desk/table.
• Move away from window
glass.
• Do not go near electric
point and cable. Keep away
from weak portion of the
building .

30. After An Earthquake
• Keep calm, switch on the transistor radio and obey
instructions.
• Keep away from beaches and low banks of river. A
huge wave may sweep in
• Do 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 lighter
• Do not turn on switches there may be gas leak or
short circuit
• If there is any fire, try to put it out or call fire
brigade.

31. Local and International response.
The response within India was
immediate. The national and state
governments quickly provided assistance
in many forms including cash, medical
supplies, communications teams,
shelters, food, clothing, transport and
relief workers.

32. Volcanic eruption

33. Volcanic eruption
A volcano is a rupture on the crust of a
planetary-mass object, such as Earth,
that allows hot lava, volcanic ash, and
gases to escape from a magma
chamber below the surface.

34. Cause of eruption
As rock inside the earth melts, its mass remains
the same while its volume increases--producing
a melt that is less dense than the surrounding
rock. This lighter magma then rises toward the
surface by virtue of its buoyancy. If the density
of the magma between the zone of its
generation and the surface is less than that of
the surrounding and overlying rocks, the magma
reaches the surface and erupts.

35. Safety Tips
• Stay away from active volcanoes.
• If you live near an active volcano,
keep goggles and a mask in an
emergency kit, along with a flashlight
and a working, battery-operated
radio.
• Know your evacuation route. Keep
gas in your car.

36. If a Volcano Erupts in Your Area
• Evacuate only as recommended by authorities to stay clear of
lava, mud flows, and flying rocks and debris.
• Avoid river areas and low-lying regions.
• Before you leave the house, change into long-sleeved shirts and
long pants and use goggles or eyeglasses, not contacts. Wear an
emergency mask or hold a damp cloth over your face.
• If you are not evacuating, close windows and doors and block
chimneys and other vents, to prevent ash from coming into the
house.
• Be aware that ash may put excess weight on your roof and need
to be swept away. Wear protection during cleanups.
• Ash can damage engines and metal parts, so avoid driving. If you
must drive, stay below 35 miles (56 kilometers) an hour.

37. Conclusion
Natural Disasters happen in many places to millions
of people and I set out to find what variable changes
how people react to all these disasters. I found out it
can be the honor system, how prepared they were, if
they underestimated the storm, and how their
buildings were structured. Informing people of what
to do if a disaster strikes saves thousands of lives, and
researching for how to structure buildings and
technology for disasters will help many others
evacuate before a disaster hits. How you are
prepared and informed changes how you will react to
disasters.

38. References
• http://www.ready.gov/natural-disasters
• www.slideshare.net/
• www.scientificamerican.com/
• www.volcano.oregonstate.edu/
• www.environment.nationalgeographic.com/

39. Thank You !