Lesson 1 Quarter 1

1. DISTRIBUTION OF ACTIVE
VOLCANOES, EARTHQUAKE
EPICENTERS, AND MAJOR
MOUNTAIN BELTS
LESSON 1

2. • Read and study the picture.
• Do you know the location of active volcanoes in the
Philippines ?
• Can you locate them in the map?

3. Active Volcanoes

4. • Our country is situated in the Pacific Ring of Fire where
the oceanic plate and several smaller micro plates sub-
ducting along the Philippine plate and sever-al microplates
along the Philippine Trench to the East and smaller
trenches to the West.

5. • To date, as per report of the PHILVOCS (Philippine
Institute of Volcanology and Seismology), there are 53
active volcanoes in the Philippines characterized by two
major NS trending arcs – the Luzon and Mindanao Volcanic
Arcs.

6. • This makes the country’s tectonic setting complex aside from
having a number of small plates squeezed between two convergent
plate margins, separated by small subduction zones and major
transform faults.
• Active

7. • Some volcanoes in the Philippines are active or dormant.
We describe volcanoes as dormant and active based from
their frequency of eruptions.
• Those that erupt regularly are called active and those
that have erupted in the past and are inactive are called
dormant.

9. • Taal, Pinatubo and Mayon volcanoes are the familiar
volcanoes of the country in terms of their eruptions.
• They are formed when pieces of earths crusts called plates
smash and buckle up through a process called plate
tectonics.

10. • Some form mountain ranges or hill ranges arranged in a
line and connected by high ground. A group of mountain
ranges with similarity in form , structure and alignment is
called a mountain belt.

11. • There are mountain ranges closest to a certain volcano.
Say for example, for Taal Volcano, they are Mount Macolod
(3107 ft.) which is 7 miles away from Taal, Mt. Talamitan
(2310 ft.), 17.3 miles away from Taal,

12. • Mount Panay (1,644 ft.) 22.2 miles from Taal and San
Pablo Volcanic Field (3576 ft.) which is 22.2 miles away
from Taal.
• Can you name the mountain ranges of other active
volcanoes in the country ?

13. • Seismic waves are the waves of energy caused by the sudden break-ing
of rock within the earth or an explosion. They are the energy that
travels through the earth and is recorded on seismographs.
• There are several different kinds of seismic waves. These waves move in
different ways.
• Body waves can travel through the earth's inner layers while surface
waves can only move along the surface of the planet like ripples on
water.
Seismologist can determine the difference in arrival times
between the P-wave and the S-waves.

14. • There are several different kinds of seismic waves.
• These waves move in different ways. Body waves can travel
through the earth's inner layers while surface waves can only
move along the surface of the planet like ripples on water.
• Earthquakes radiate seismic energy as both body and surface
waves. Traveling through the interior of the earth, body waves
arrive before the surface waves emitted by an earthquake.

15. • These waves are of a higher frequency than surface
waves.
• The first kind of body wave is the P wave or primary
wave.
• This is the fastest kind of seismic wave, and, consequently,
the first to 'arrive' at a seismic station.

16. • The P wave can move through solid rock and fluids, like
water or the liquid layers of the earth.
• It pushes and pulls the rock it moves through just like
sound waves push and pull the air.
• P waves are also known as compressional waves,
because of the pushing and pulling they do.

17. • Seismologists use triangulation to find the epicenter of an
earth-quake. When seismic data is collected from at least
three different locations, it can be used to determine the
epicenter by where it intersects.
• Every earthquake is recorded on numerous seismographs
located in different di-rections.

18. • Each seismograph records the times when the first (P
waves) and second (S waves) seismic waves arrive.
• From these, seismologist can determine how fast the
waves are traveling. Knowing this helps them calculate the
distance from the epicenter to each seismograph.

19. • Earthquake is the shaking of the earth’s surface that often
causes a great damage. Epicenter is the part of the earth’s
surface that is directly above the place where earthquake
starts.
• Volcanoes are a mountain with ahole in the top or side that
sends out rocks, ash, lava, and etc. and mountain ranges are
succession of many closely spaced mountains covering a
particular portion of earth.

20. • The location of most active volcanoes, earthquake
epicenters, and mountain ranges are found in the Pacific
Ring of Fire or in the Pacific Ocean basin.

21. • Activity 1: Complete the table below. Using the picture to
describe its observable or physical characteristics.
Activity

23. • Activity 2: Below is a map showing the location of the
active volcanoes, earthquake prone areas and mountain
ranges in the Philippines. List them down. Describe their
locations.

26. • Activity 3: Using the world map, locate and list down the
location of active volcanoes , earthquake zones and
mountain ranges in the world.

27. • Location of active volcanoes, earthquake epicenters, and
mountain ranges in different Continents

28. • Questions:
• 1. Based on the map, list down the places where you can find
the following;
• a. volcanoes
• b. earthquake epicenters
• c. mountain ranges

29. • 2. Why do active volcanoes, mountain ranges/folded
mountains, and earth-quake zone are located in the same
place?
• 3. Explain why those places in the map have active
volcanoes, earthquake epicenters and mountain ranges.

30. • Activity 4: Complete the concept map. Copy this in your
notebook.
• Use the paragraph before the concept map as your guide
to look for more information from other sources.