Science lesson

1. SCIENCE 9
3RD
QUARTER - LESSON 1

2. LESSON 1
EARTH AND SPACE:
DIFFERENT TYPES OF
VOLCANOES

3. In this lesson, we will explore the similarities and differences
between mountains and volcanoes. Both are landforms
that rise above Earth's surface, but they form in different
ways.
You will be dealing with the volcanic structure and the
different types of volcanoes based on structure and
activity, and types of volcanic eruptions.

4. You will also explore the different examples of volcanoes
found in the Philippines as well as the signs of impending
volcanic eruption.
You are expected to create materials that can provide
awareness on signs of a forthcoming volcanic eruption
especially to people or community living near an active
volcano.

5. MOUNTAIN VS.
VOLCANO
A mountain is a large natural elevation
of the Earth's surface that rises
prominently above its surroundings.
Mountains are formed mainly due to
tectonic forces or volcanism.

6. MOUNTAIN VS.
VOLCANO
Some mountains are considered
volcanoes because they were formed
by volcanic activity — that is, by
magma (molten rock) coming from
beneath the Earth’s surface.

7. MOUNTAIN VS.
VOLCANO
Mountains can form in different ways, like when
tectonic plates collide and push the land upward.
Volcanoes, on the other hand, are a special type of
mountain that forms when magma erupts through
the Earth’s crust and piles up over time.
So, all volcanoes are mountains, but not all
mountains are volcanoes.

8. MOUNTAIN VS.
VOLCANO
✅ Example:
Mount Mayon in the Philippines is both a mountain
and a volcano because it was formed by repeated
eruptions of lava and ash.
Mount Everest, however, is not a volcano—it was
formed by the collision of tectonic plates, not by
magma.

9. TYPES OF MOUNTAIN
1. Fold Mountains –
formed by the
folding of Earth's
crust.

12. TYPES OF MOUNTAIN
2. Fault-block
Mountains –
formed when
large blocks of
Earth's crust are
uplifted.

16. TYPES OF MOUNTAIN
3. Dome
Mountains –
formed from
magma pushing
the crust upward.

19. TYPES OF MOUNTAIN
4. Volcanic
Mountains –
formed by
volcanic
activity.

22. Say four (4) words that you can associate with the word
“volcano” by completing the graphic organizer.

23. STRUCTURE OF A
VOLCANO
The term “volcano” refers to mountain or hill,
typically conical, having a crater or vent in which
lava, rock fragments, hot vapor, and gas are or
have been erupted from the earth's crust.
The lava and other volcanic materials originated
from molten materials called magma found
beneath the surface of the Earth.

24. STRUCTURE OF A
VOLCANO
Magma and other volcanic materials are
finding its way to the surface where they
are expelled through openings like cracks
and holes.
Any activity that includes the movement
of magma towards or onto the surface is
called volcanism.

25. STRUCTURE OF A
VOLCANO

26. STRUCTURE OF A VOLCANO
The Parts of a Volcano are:
⮚ Summit is the highest
point or the apex of the
volcano. At the summit,
you have an opening called
vent.
⮚ Slopes are the sides or
flanks of a volcano that
radiate from the main or
central vent.
⮚ Base is lower outer part of
the volcano.

27. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Magma Chamber is a region
beneath the vent of a
volcano where molten rock
or magma is deposited or
stored before eruption.

28. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Main Vent is the main
opening or outlet on the
surface of a volcano that
emits lava, gases, ash or
other volcanic materials.

29. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Conduit is an underground
central tube-like or pipe-like
structure of a volcano that
connects the magma
chamber to the crater
through which the magma
travels.

30. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Side Vent is a smaller outlet
through which magma
escapes.

31. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Lava is a molten rock
which is given off onto
the surface of the Earth
when a volcano erupts.

32. STRUCTURE OF A VOLCANO
Other Geologic features of a
volcano:
• Ash and Gas Cloud is a of
mixtures of rock, minerals,
glass particles and gases
expelled or pushed out of
the volcano during volcanic
eruption.

33. CLASSIFICATION OF
VOLCANOES
There are several ways by which volcanoes can
be classified. They can be classified based on
structure and activity.

34. TYPES OF VOLCANOES
BASED ON STRUCTURE
One way to classify different types of volcanoes
is through the structure characterized by their
shape, parts and formation.

35. TYPES OF VOLCANOES BASED ON
STRUCTURE
1. Cinder Cone Volcano Cinder cone volcanoes- are the simplest
type of volcano.
 They are built from particles and
blobs of solidified lava ejected from a single
vent.
 Lava is thrown into the air, which breaks
into small fragments that solidify and fall
as cinders around the vent to form a
circular or oval cone.
 Most cinder cones have a steep slope, wide
crater and are the most abundant of the three
major volcano types.

36. TYPES OF VOLCANOES BASED ON
STRUCTURE
1. Cinder Cone Volcano
An example of this type in the
Philippines are Taal Volcano in Batangas,
Smith Volcano found in Babuyan Group
of Islands, Mount Mayabobo found in
Quezon Province, and Mount Musuan in
Bukidnon.
An example of this outside of the
Philippines is the Paricutin volcano in
Mexico.

37. TYPES OF VOLCANOES BASED ON
STRUCTURE
Cinder Cone Volcano
TAAL VOLCANO MOUNT MAYABOBO

38. TYPES OF VOLCANOES BASED ON
STRUCTURE
Cinder Cone Volcano
MOUNT MUSUAN SMITH VOLCANO

39. TYPES OF VOLCANOES BASED ON
STRUCTURE
2. Composite Volcano
Composite volcanoes or stratovolcanoes are
large, typically steep- sided, symmetrical
cones of large dimension formed from
alternating layers of lava flows, volcanic ash,
cinders, blocks, and pyroclastic materials.
One important feature of a composite
volcanoes is the conduit system from which
magma rises to the surface of the Earth. They
are formed from viscous, or sticky, lava that
does not flow easily. The lava builds up
around the vent forming a volcano with steep
sides.

40. TYPES OF VOLCANOES BASED ON
STRUCTURE
2. Composite Volcano Some famous composite volcanoes in
the Philippines are Mount Mayon in
Albay, Mount Arayat in Pampanga,
Mount Kanlaon in Negros Island, and
Mount Apo in Davao Region.
An example of these outside the
Philippines are Mount Rainier in
Washington, USA, and Mount Fuji in
Japan.

41. TYPES OF VOLCANOES BASED ON
STRUCTURE
Composite Volcanoes
MOUNT MAYON MOUNT ARAYAT

42. TYPES OF VOLCANOES BASED ON
STRUCTURE
Composite Volcanoes
MOUNT KANLAON MOUNT APO

43. TYPES OF VOLCANOES BASED ON
STRUCTURE
Composite Volcanoes
MOUNT RAINIER MOUNT FUJI

44. TYPES OF VOLCANOES BASED ON
STRUCTURE
3. Shield Volcano
Shield volcanoes are large, broad
volcanoes that look similar to shields
from above – hence the name.
These volcanoes are built almost
entirely of fluid lava flow thus these
volcanoes are not steep. They can be
easily identified because they are tall and
broad, with flat, rounded shapes.
The lava is not accompanied
by pyroclastic materials, which makes
shield volcanoes relatively safe.
Eruptions at shield volcanoes are only
explosive if water somehow
gets into the vent.

45. TYPES OF VOLCANOES BASED ON
STRUCTURE
Mauna Loa is one
of the largest
shield volcanoes.
MAUNA LOA

46. TYPES OF VOLCANOES BASED ON
STRUCTURE
Cabalian
volcano- is an
example of a
shield volcano
that can be
found in the
Philippines.

47. TYPES OF VOLCANOES
BASED ON ACTIVITY
Another way of classifying volcanoes according to
the Philippine Institute of Volcanology and
Seismology (PHIVOLCS) is based on their activity
as indicated by their behavior and historical
records.

48. TYPES OF VOLCANOES
BASED ON ACTIVITY
 Active volcanoes are those volcanoes that
have had at least one eruption during the
past 10,000 years. They are those that
erupted recently and still showing regular
activity like emission of gases, lava and ash
flows.

50. TYPES OF VOLCANOES
BASED ON ACTIVITY
 Inactive volcanoes, are those that have not erupted for
the last 10,000 years and is not expected to erupt again in a
comparable time scale of the future. There are no signs of
volcanic activity for a long period of time because magma
supply is cut off. Also the physical form of the volcano has
signs of intensive weathering and erosion

51. Inactive volcanoes in the Philippines

52. TYPES OF VOLCANOES
BASED ON ACTIVITY
Potentially active volcanoes are those that have no
records of volcanic activity but are morphologically
young-looking.

54. The Philippines has a total of approximately 400
volcanoes, with around 24 classified as active,
over 24 as potentially active, and the remaining
majority as inactive.
Active volcanoes have erupted in the last 10,000
years, while potentially active volcanoes have a
young appearance but no historical records of
eruptions. Inactive volcanoes show no signs of
recent volcanic activity.

55. THANK YOU!