POTENTIAL
EARTHQUAKE
HAZARDS AND
THEIR
EFFECTS

WHAT DO YOU
THINK OF WHEN
YOU HEAR THE
WORD
EARTHQUAKE.

Shaking
Damages
 collapse of
building
 injuries, deaths,

 bridge
collapsed
people trap
inside the
building
isolated places

EARTHQUAKE
feeble shaking to
violent trembling of the
ground produced by the
sudden displacement of
rocks or rock materials
below the earth’s
surface.

2 TYPES OF EARHQUAKE
Tectonic earthquakes
are those generated by
the sudden displacement
along faults in the solid
and rigid layer of the
earth.

TECTONIC
Plate tectonics –
leading to
mountain building,
volcanism, ocean
formation, etc.

THREE KINDS
OF TECTONIC
BOUNDARIES

1. DIVERGENT BOUNDARIES
Occurs when two tectonic
plates move away from
each other.
Along these boundaries
Lava spews.
Frequent earthquakes
strike along the rift.

CONVERGENT BOUNDARIES
When two plates come
together
 The impact of the two
colliding plates buckles
the edge of one or both
plates up into a rugged
mountain range

Sometimes bends the
other down into a deep
seafloor trench
A chain of volcano often
forms
Powerful earthquakes
shake a wide area on both
side of the boundary

TRANSFORM PLATE BOUNDARY
Two plates sliding past
each other.
Natural or human made
structures that cross a
transform boundary are off
set-split into pieces and
carried in opposite
directions.

Rocks that line the
boundary are pulverized as
the plates grind along
creating a linear fault valley
or undersea canyon.
As the plates alternately
jump against each other
erathquakes rattle.

VOLCANIC
EARTHQUAKES. Earth
quakes induced by
rising lava or magma
beneath active
volcanoes

FAULT
Fault- refers to a fracture,
fissure or a zone of weakness
or fracture of rock where
movement or displacement
has occurred or may occur
again

“active fault” if it has historical
and contemporary seismicity, has
evidence of fault slip based on
displaced rocks or soil units of
known age and displaced
landforms; an active fault is
defined as a fault which has
moved within the last 10,000
years

ASSIGNMENT
Why are these
earthquake
events
remembered?

Because of its
impacts, the damages,
the deaths and
injuries, it directly
affected learner,
affected relatives,

EARTHQUAKE-
RELATED HAZARDS

GROUND SHAKING
disruptive up-down and
sideways movement
motion experienced
during an earthquake.

 A. Strong ground shaking can cause objects to
fall, break windows among others.
 B. Strong ground shaking can also result to
minor damages to buildings and worse, cause
collapse of a structure. (e.g. collapse of Hyatt
Hotel, Baguio City after the 16 July 1990
Luzon Earthquake).
 C. Most part of the Philippines will experience
shaking at different degrees depending on
magnitude of earthquake, distance of one’s
location from the fault that moved, local below
surface conditions, etc)

GROUND RUPTURE
- displacement
on the ground
due to movement
of fault .

This will be experienced by areas
where fault passes through (note not
all cracks on the ground that people
see after a strong earthquake are
faults, some may just be surficial
cracks because of ground failure)
B. The movement may have vertical
and horizontal component and may be
as small as less than 0.5 meters
(Masbate 1994 earthquake) to as big
as 6 meters (16 July 1990 Earthquake).

TSUNAMI
sea waves
resulting from the
disturbance of
ocean floor by an
earthquake

This is a series of giant sea waves
commonly generated by under-the-sea
earthquakes and whose heights could
be greater than 5 meters.
B. Examples of recent tsunami events
in the Philippines are the August 1976
Moro Gulf Earthquake and Tsunami
and the November 1994 Oriental
Mindoro Earthquake and Tsunami,
December 2004 Banda Aceh
Earthquake (Indonesia), and March
2011 Eastern Japan

LIQUEFACTION
is a process that
transforms the behavior of
a body of sediments from
that of a solid to that of a
liquid when subjected to
extremely intense shaking.

As a result, any heavy
load on top of the sediment
body will either sink or tilt
as the sediment could no
longer hold the load, such
as what happened in
Dagupan City during the
16 July 1990 earthquake.

EARTHQUAKE-INDUCED
LANDSLIDE
- failures in
steep or hilly
slopes triggered
by an

loose thin soil
covering on the slopes
of steep mountains are
prone to mass
movement, especially
when shaken during
an earthquake.

B. • Many landslides occur
as a result of strong ground
shaking such as those
observed on the
mountainsides along the
National Highway in Nueva
Ecija and the road leading
up to Baguio City during the
16 July 1990 earthquake.

IN WHICH
ENVIRONMENT
EACH OF THE
HAZARD IS
EXPERIENCED OR IS
MORE
PROMINENT.

based on what they
have learned so far,
think of your home,
what are the possible
impacts/ effects of the
5 earthquake hazards
to your home/s?

 Ground Rupture (only if a fault
passes through my home) (Note: This
will be important for areas with
known presence of faults)
 Ground shaking: Yes
 Liquefaction (Note, only for areas
near rivers, coastal areas, underlain
by soft sediments or water-saturated
materials)
 Earthquake-induced landslide (if my
home is near/ at the base or on the
slope of a mountain side)
 Tsunami (if my home is near the
coast)

What are the potential
hazards that can affect me,
my home and my
community.
 How?
Will I be affected by (check
all the will apply)

Those I have
checked are
the hazards I
need to
prepare for.

FAULT

a zone of
weakness where
movement or
displacement has
occurred or may
occur again

ACTIVE FAULT
Any fault that is likely to
have another earthquake
sometime in the future
 if they have moved one or
more times in the last 10,
000 years

ACTIVE
FAULTS IN
THE
PHILIPPINES

West and
east valley
fault
Western
phil. Fault
Eastern
phil fault.
South of
mindanao
fault
Central phil
fault
Rodriguez,
rizal
San, mateo
rizal
Marikima
Pasig
Taguig
Muntinlupa
San pedro
Binan
Carmona
Santa rosa
Calamba
Tagaytay
oriental
mindora
Luzon sea
Mindoro
strait
Panay Fault
Sulu Sea
Philippine
Sea
Moro gulf
Celebes sea
Ilocos sur
Ilocos norte
La union
Pangasinan
Nueva Ecija
Aurora
Quezon
Masbate
Eastern Leyte
Southern
Leyte
Agusan del
Norte
Agusan del
sur
Davao del
norte

1990 luzon
earthquake
–baguio and rest of
the central luzon
(due to Central phil
fault)

WEST AND EAST VALLEY
FAULT
Former Marikina
valley fault
Is being closedly
monitored by
PHILVOCS

The west valley fault
movement is mainly
horizontal
Movement interval is 400
years
Last major earthquake
happened last 1658
Affect metro manila manila
and vicinity

JICA( Japan international
Cooperation Agency
MMDA (Metropolitan
Manila Development
Authority)
PHILVOCS (Philippine
Institute of volcanology
and seismology)

Fault moves and generate a
7.2 magnitude of earthquake
34000 deaths,
600,000 cases of injury
500 incidents of fire
simultaneously
“THE BIG ONE”

JAMES HUTTON
Father of modern geology
He believed that earth
was continuously being
formed
Because of his
contributions Geology was
established as a proper
science.

DR. RAYMUNDO PUNONGBAYAN
Director of PHILVOCS
from 1983 to 2002
He was known for 2
events
1. 1990 luzon earthquake
2. Mount pinatubo
eruption

He closedly monitored mount
pinatubo when it started to show
some volcanic ativity.
He constant remind the
residents of zambales, tarlac and
pampanga before the eruption.
He was able to show proof that
mount pinatubo was alive and
ready to blow up.
Because of this he saved a lot of
lives.

MMEIRS( METRO MANILA EARTHQUAKE
IMPACT REDUCTON STUDY )
Objectives
Evaluate seismic hazard ,
damages and vulnerability of
metro manila
Prepare framework of master
plan for earthquake disaster
management

OPERATION METRO YAKAL
An operation to be followed
in case the “Big One” does
happen.
Metro will be divided into
quadrants, each with its own
designated areas for
evacuation.

CAN ANIMALS
PREDICT
EARTHQUAKE
S???

According to United states
Geological Survey (USGS)
Earliest reference-373 BC
Rats, weasels snakes and centipedes
reportedly left their homes and
headed for safety days before a
destructive earthquake..
Evidence of animals, fish , birds,
reptiles and insects exhibiting
behavior strange behavior anywhere
from weeks to seconds before an
earthquake.

HOW TO
DESCRIBE THE
STRENGTH OF
AN
EARTHQUAKE

2 WAYS TO
DESCRIBE
EARTHQUAKE

MAGNITUDE
A measure of earthquake size
with respect to the distance from
the earthquake origin
Measurement requires an
instrumental monitoring for its
calculation

INTENSITY
Degree of shaking caused
by an earthquake at a
given place and decreases
with distance from the
earthquake origin or
epicenter

SEISMOGRAPH OR
SEISMOMETER
Measure the strength of
an earthquake.
A measuring instrument
that create the
seismogram..(a record of
the seismic waves from an
earthquake)

PRECAUTIONARY
AND SAFETY
MEASURES

Priority:
To lessen the impact
a. Choose the area to build
infrastructures
b. Check the stability of objects
that are hung on walls or
inside caniets

THINGS TO DO
BEFORE,
DURING AND
AFTER AN
EARTHQUAKE