Republic of the Philippines

Department of Education
Regional Office IX, Zamboanga Peninsula

11 Zest for Progress

Z Peal of artnership

Earth Science
Quarter 2 - Module 4
Ocean Basin, Trenches, and
Plate Movement

Name of Learner: ___________________________

Grade & Section: ___________________________
Name of School: ___________________________
Module Ocean Basin, Trenches, and Plate

4 Movement

What I Need to Know

This Module was written with you in mind. It is here to help you master
the Structure and Evolution of Ocean Basins and to know How the Movement
of Plates Leads to the Formation of Folds and Faults, Trenches, Volcanoes,
Rift Valleys and Mountain Ranges (S11ES - llf-33, S11ES-llg-h-34). The
lessons are arranged to follow the standard sequence of the course. But the
order in which you read them can be changed to be similar to the textbook
you are using.

This Module contains the lesson on The Structure and Evolution of

Ocean Basins ad the Movement of Plates.

After going through this module, you should be able to:

1. Describe the structure and Evolution of Ocean Basins

2. Explain how the movements of plates leads to the formation of faults and
folds;

3. Identify the different types of plates.

What’s In
Throughout most of the geologic time, probably extending back 2 billion
years ago, the ocean basins have both grown and consumed as plate tectonics
continued on the Earth. Ocean basins are formed geologically of oceanic
(basalt) crust, in contrast to continental (granite) crust that forms the Earth’s
major land masses. Thus some smaller “seas” that are underlain by ocean
crust and are isolated from the world ocean as separate basins, such as the

2
Mediterranean, Tasman, Coral, Caribbean, and the Red Seas, may be
considered oceanic. By contrast, other shelf seas and gulfs are perched
on continental crust (e.g., the North Sea, Arafura Sea, Baltic Sea, Yellow Sea)
and are consequently distinguished on a geological basis from oceanic basins.
Score: ____/ 10
Activity 1. Label Me, Please!
Directions: Label the parts of the topography of the ocean basin. (1 point
each)

https://www.sciencedirect.com/topics/earth-and-planetary-sciences/ocean-basin

Score: ____/ 10

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 What’s New
Activity 2: Identify Me, Please!

Directions: Identify the term/s being described in each statement below.

Choose your answer from the word box and write it on the space provided
before the number. (1 point each)

Radar Sonar Abyssal Hill Seamount

Seafloor abyssal plain Ocean floor

Continental rise Continental shelf break Continental slope

Ocean Trenches Continental Shelf

____________1. An Instrument that accurately determines the time between

the emission of strong acoustic pulse and the detection of its echo.
____________2. Is found at the base of the continental rise in water 4000 to
6000 meters deep.
____________3. These are long, narrow, steep-sided depressions found on the
ocean floor that contain the greatest depths in the ocean.
____________4. It is found at the base of the continental slope.
____________5. It is a shallow, gently sloping part of the continental crust with
an average range depth of 130 meters.
____________6. It extends from the continental shelf at an average depth of
135 meters.
____________7. It is the boundary between the continental slope and shelf.
____________8. It is defined as a small elevated landform that rises from the
great depths of the ocean.
____________9. Simply defined edges but is relatively small, generally not
higher than 500 feet and few miles wide.
___________10. It is a large submerged volcanic mountain rising from the
ocean floor.

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 What Is It
Throughout most of geologic time, probably extending 2 billion years
ago, the ocean basins have both grown and consumed as plate tectonics
continued on Earth.
Crustal plates move gradually and converge at their boundaries. These
boundaries are common areas of tectonic activity which causes the
deformation of the Earth’s crust. Tectonic activities include earthquake,
volcanism and mountain formation. All this results in the creation of many
ocean basin features.
Much of the general information concerning the depth of the ocean was
made after WWI. Many topographic features that exist on the ocean basin are
obtained by using echo sounder which was primarily developed for military
purposes, side-scan sonar and satellites that measure the height of sea
surfaces.
Sonar is an instrument that accurately determines the time between
the emission of a strong acoustic pulse and the detection of its echo. Using
the principle of sound reflection, scientist can determine the depth of the
ocean.
Plates can spread apart by moving away from each other. This creates
gas where hot molten rock, called magma from the Earth’s mantle walls up.
When magma seeps through the gaps, it solidifies as it cools, creating a new
layer ocean crust. This creates structures such as oceanic ridges, which are
continuous mountain chains located under the sea. Mid-oceanic ridge is
normally found rising above the ocean floor at the center of the ocean basins.
Some volcanic islands are part of the mid-ocean ridges system like Iceland.
The mid-oceanic ridge constitutes 25 % of the Earth’s surface. In the center
of the mid-oceanic ridge is a rift valley between 30-50 km wide, dissects 1000-
3000 meters deep into the ridge system.
An abyssal plain is another raised feature found on the ocean basins.
It is defined as small elevated landform that rises from the great depths of the

5
ocean. The word “abyss” which means very deep will help you remember the
term abyssal hill. An abyssal hill has simply defined edges but is relatively
small, generally not higher than 500 feet and few miles wide. A seamount is
a large submerged volcanic mountain rising from the ocean floor. Seamounts
can be very large.
Ocean trenches are long narrow, steep-sided depressions found on the
ocean floor that contain the greatest depths in the ocean (11,000m in Western
Pacific). There are 26 oceanic trenches in the world: 3 in the Atlantic Ocean,
1 in the India Ocean and 22 in the Pacific Ocean. Ocean trenches mark the
transition between continents and ocean basin, especially in the Pacific.
Ocean floor is found at the base of the continental rise in water 4000 to
6000 meters deep. The ocean floor accounts for nearly 30% of the Earth’s
surface. Numerous volcanoes are found on the ocean floor of the ocean basins.
Scientists estimate that there are about 10,000 volcanoes on the ocean floor.
The continental rise is found at the base of the continental slope. The
depth of the rise ranges from 2,000 to 5,000 meter deep. Its breadth is up to
300 km wide.
Continental shelf is a shallow, gently sloping part of the continental
crust with an average depth of 130 meters that borders the continents. The
extent of this feature varies from tens of meters to a maximum width of about
1300 kilometers.
The continental slope extends from the continental shelf at an average
depth of 135 meters. The base of this steeply sloping (averaging from 1 to 250)
topographic feature occurs at a depth of approximately 2000 meters, marking
the edge of continents. Both the continental shelf and slope are considered
structurally part of the continents, even though they are below the sea
surface. The boundary between the continental shelf and slope is called a
continental shelf break.
The ocean basins are the result of tectonic forces and processes. All of
the ocean basins were formed from volcanic rock that was released from
fissures located at the mid-oceanic ridges. The oldest rocks found in this
ocean basin are approximately 200 million years old. This is a lot younger
than the oldest continental rocks which aged greater than 4 billion years. The

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reason for this difference is simple. Tectonic processes destroy old oceanic
rocks. Oceanic rock is returned to the Earth’s mantle when oceanic crust is
subducted. Many of these subduction zones occur at the continental margins
where the oceanic crust meets continental crust. Subduction also creates the
ocean’s deep trenches.
There are a few handfuls of major plates and dozens of smaller, or
minor, plates. Six of the majors are named for the continents embedded
within them, such as the North American, African, and Antarctic plates.
Though smaller in size, the minors are no less important when it comes to
shaping the Earth. The tiny Juan de Fuca plate is largely responsible for
the volcanoes that dot the Pacific Northwest of the United States.
The movement of the plates creates three types of tectonic boundaries:
convergent, where plates move into one another; divergent, where plates
move apart; and transform, where plates move sideways in relation to each
other. They move at a rate of one to two inches (three to five centimeters) per
year.
Where plates serving landmasses collide, the crust crumples and
buckles into mountain ranges. India and Asia crashed about 55 million
years ago, slowly giving rise to the Himalaya, the highest mountain system
on Earth. As the mash-up continues, the mountains get higher. Mount
Everest, the highest point on Earth, may be a tiny bit taller tomorrow than
it is today.

These convergent boundaries also occur where a plate of ocean dives,

in a process called subduction, under a landmass. As the overlying plate lifts
up, it also forms mountain ranges. In addition, the diving plate melts and is
often spewed out in volcanic eruptions such as those that formed some of
the mountains in the Andes of South America.

At ocean-ocean convergences, one plate usually dives beneath the

other, forming deep trenches like the Mariana Trench in the North Pacific
Ocean, the deepest point on Earth. These types of collisions can also lead to
underwater volcanoes that eventually build up into island arcs like Japan.

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 At divergent boundaries in the oceans, magma from deep in the
Earth's mantle rises toward the surface and pushes apart two or more
plates. Mountains and volcanoes rise along the seam. The process renews
the ocean floor and widens the giant basins. A single mid-ocean ridge system
connects the world's oceans, making the ridge the longest mountain range
in the world.

On land, giant troughs such as the Great Rift Valley in Africa form
where plates are tugged apart. If the plates there continue to diverge,
millions of years from now eastern Africa will split from the continent to form
a new landmass. A mid-ocean ridge would then mark the boundary between
the plates.

The San Andreas Fault in California is an example of a transform

boundary, where two plates grind past each other along what are called
strike-slip faults. These boundaries don't produce spectacular features like
mountains or oceans, but the halting motion often triggers large
earthquakes, such as the 1906 one that devastated San Francisco.

What’s More
Score: ____ / 12
Activity 3: Where Am I Located?
Directions: Analyze carefully the map below and determine the exact location
of the different minor and major plates located in the world. Choose your
answer on the following: African Plate, Antarctic Plate, Eurasian Plate, Pacific
Plate, Indo-Australian Plate, North American Plate, South American Plate,
Arabian Plate, Caribbean Plate, Cocos Plate, Nazca Plate, Juan de Fuca Plate,
Philippine Sea Plate, Scotia Plate, Okhotsk Plate. Examples: M is Philippine
Sea Plate; N is Antarctic Plate; and O is Okhotsk Plate.

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 A. E. I.
B. F. J.
C. G. K.
D. H. L.
Score: ____ / 9

What I Have Learned

You know now that mountain ranges, seamount, and volcanoes rise
from the movement of plates. You have also learned that there are different
types of plate boundaries that separates continents and oceans. You are also
aware of the fact that there are major and minor plates that can make a great
impact on my life should there be a movement from these plates.

Activity 4: My Evidence of Plate Boundaries

Directions: Write the geological evidence that support divergent boundaries

(i.e. mid-ocean ridge), and convergent boundaries (i.e. subduction zones) in
the table below.

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 Divergent plate boundaries Convergent plate boundaries
(5 points) (4 points)

Score: ____ / 5
Activity 5: Am I Divergent or Convergent?

Directions: Identify whether it is Divergent or Convergent. Write your answer

on the space provided before each number. (1 point each)

_________1. Magma rise

_________2. Longest Mountain Range
_________3. Himalaya
_________4. Andes of South America
_________5. Mariana Trench

What I Can Do
The Philippine Sea Plate or the Philippine Plate is a tectonic
plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to

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the east of the Philippines. Most segments of the Philippines, including
northern Luzon, are part of the Philippine Mobile Belt, which is geologically
and tectonically separate from the Philippine Sea Plate. Philippine Sea plate
is bordered mostly by convergent boundaries.

Activity 6. Synthesis
Directions: Explain how the Philippine Sea Plate or the Philippine Plate affect
the Philippines. Write your answer below. Refer table 1 below for your rubric.

Answer:

__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
__________________________________________________
Table 1. Rubrics for Essay

Features Expert Accomplished Capable Beginner

(5) (4) (3) (2)
Thought Thoughts are Thoughts are Thoughts are Thoughts are
Process very well well organized inorganized but not
organized and show strong points are organized
points visible and show a
little point
Grammar No Few grammatical Punctuations Grammar
Usage grammatical errors found are unclear and
error found punctuation
not visible

Score: ____ / 15

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 Assessment
Multiple Choice. Write the letter that corresponds to the correct answer
before the number.

__1. The movement of the plates creates three types of tectonic boundaries,
EXCEPT;

a. Divergent c. subduction

b. Convergent d. Transform

__2. Which of the following is not part of the major plates?

a. Antarctic Plate c. North America Plate

b. South America Plate d. Philippine Sea Plate

__3. Which among the following is described as two plates grind past each
other along what are called strike-slip fault?

a. Divergent Plate c. Convergent Plate

b. Transform Plate d. Subduction zone

__4. It is described as plates moving apart with each other

a. Divergent Plate c. Convergent Plate

b. Transform Plate d. Subduction zone

__5. These are plates that move into one another.

a. Divergent Plate c. Subduction zone

b. Convergent Plate d. Transform Plate

__6. It is a deep trench located at the North Pacific Ocean.

a. Philippine Trench c. Kermadec Trench

b. Mariana Trench d. Kamchatka Trench

__7. Which among the following is the highest point on Earth?

a. Mount Fiji c. Mount Everest

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 b. Mount Apo d. The Himalayas

__8. It is largely responsible for the volcanoes that dot the Pacific Northwest
of the United States.
a. Philippine Plate c. North Atlantic Plate
b. North America Plate d. Juan de Fuca Plate

__9. _______ crashed about 55 million years ago slowly giving rise to the
Himalayas.

a. India and Asia c. India and Eurasia

b. India and Africa d. India and Japan

__10. How are oceanographers and scientists able to map the sea floor?

a. By scuba diving c. by using radars

b. by using telescope d. by using sonars

__11. Which of the following portions of the ocean floor is the flattest?

a. Abyssal Hill c. Ocean Trenches

b. Abyssal Plains d. Continental Slope

__12. Where is the ocean floor deepest?

a. In rift valleys c. In abyssal plains

b. In oceanic trenches d. in abyssal hills

__13. What is the process referring to the sinking of ocean floor beneath the
deep ocean trench and back into the mantle?

a. Conduction c. Convection

b. Continental drift d. Subduction

__14. The ____________ in California, USA is an example of transform plate.

a. San Francisco c. Malibu

b. San Andreas d. Los Angeles

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__15. Which of the following is a portion of the world’s longest mountain
range?

a. Caledonides c. Mariana Trench

b. Himalayas d. Mid-oceanic Ridge

Additional Activity
ACTIVITY 7: Tell Me What You Think Score: ____ / 20

Directions: Read the following statements. Then answer the guide questions
that follow. Each question bears a 10-point score. Use the spaces provided for
your answer. Refer Table 1 for your rubric.

NOTE: Use separate sheet of paper for this activity.

The Ring of Fire, also referred to as the Circum-Pacific Belt, is a path

along the Pacific Ocean characterized by active volcanoes and frequent
earthquakes. Its length is approximately 40,000 kilometers (24,900 miles). It
traces boundaries between several tectonic plates—including the Pacific,
Juan de Fuca, Cocos, Indian-Australian, Nazca, North American, and
Philippine Plate.

Seventy-five percent of Earth’s volcanoes—more than 450 volcanoes—

are located along the Ring of Fire. Ninety percent of Earth’s earthquakes occur
along its path, including the planet’s most violent and
dramatic seismic events.

Guide Questions:

1. The Philippines is included in the ring of fire. Is this the reason why the
Philippines experienced devastating earthquakes recently? If so, why?

2. As a student of Earth Science, what can you do to prevent these hazards?

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 References
Images
https://www.google.com.ph/search?q=ocean+basin+diagram&tbm=isch&ved=2ah
UKEwiBkrGL0fbrAhXwx4sBHW2_D_YQ2-
cCegQIABAA&oq=ocean+basin+diagram&gs_lcp=CgNpbWcQAzICCAAyBggAEAUQHj
IGCAAQBRAeOgQIABBDOgUIABCxAzoHCAAQsQMQQzoGCAAQCBAeULuHAVj-
rAFg8K4BaABwAHgEgAHSAogBziiSAQgwLjkuMTQuMZgBAKABAaoBC2d3cy13aXot
aW1nsAEAwAEB&sclient=img&ei=O7dmX8GIMfCPr7wP7f6-
sA8&bih=730&biw=1517&hl=en#imgrc=O8f4ImIl65ZLVM
https://www.google.com.ph/search?q=plate+boundaries++no+label
https://www.google.com/search?q=different+ocean+trenches&rlz

Websites
https://www.nationalgeographic.com/science/earth/the-dynamic-earth/plate-
tectonics/
https://www.nationalgeographic.org/encyclopedia/ring-fire/

Books
Earth and Life Science (Bayo-ang, et. al, 2016) pp 75, 80-83

Development Team Mi Ultimo Adios

Adiós, Patria adorada, región del sol querida, Deja que el sol, ardiendo, las lluvias evapore
Writer: Jeff Oliver B. Fabie Perla del mar de oriente, nuestro perdido Edén! Y al cielo tornen puras, con mi clamor en pos;
A darte voy alegre la triste mustia vida, Deja que un ser amigo mi fin temprano llore
Y fuera más brillante, más fresca, más florida, Y en las serenas tardes cuando por mí alguien ore,
Editors: Margie Lou C. Jacob También por ti la diera, la diera por tu bien. ¡Ora también, oh Patria, por mi descanso a Dios!

Laarni A. Adonis En campos de batalla, luchando con delirio, Ora por todos cuantos murieron sin ventura,
Kathleen Joy B. Padilla Otros te dan sus vidas sin dudas, sin pesar; Por cuantos padecieron tormentos sin igual,

Joly C. Baradero El sitio nada importa, ciprés, laurel o lirio,

Cadalso o campo abierto, combate o cruel martirio,
Por nuestras pobres madres que gimen su amargura;
Por huérfanos y viudas, por presos en tortura
Lo mismo es si lo piden la patria y el hogar. Y ora por ti que veas tu redención final.

Reviewer: Sandy R. Albarico Yo muero cuando veo que el cielo se colora Y cuando en noche oscura se envuelva el cementerio
Management Team: Y al fin anuncia el día tras lóbrego capuz; Y solos sólo muertos queden velando allí,
si grana necesitas para teñir tu aurora, No turbes su reposo, no turbes el misterio,
Vierte la sangre mía, derrámala en buen hora Tal vez accordes oigas de cítara o salterio,
Majarani M. Jacinto, Ed.D., CESO VI Y dórela un reflejo de su naciente luz. Soy yo, querida Patria, yo que te canto a ti.

SDS-ZDS Mis sueños cuando apenas muchacho adolescente, Y cuando ya mi tumba de todos olvidada
Mis sueños cuando joven ya lleno de vigor, No tenga cruz ni piedra que marquen su lugar,
Fueron el verte un día, joya del mar de oriente, Deja que la are el hombre, la esparza con la azada,
Visminda Q. Valde, Ed.D. Secos los negros ojos, alta la tersa frente, Y mis cenizas, antes que vuelvan a la nada,
ASDS Sin ceño, sin arrugas, sin manchas de rubor El polvo de tu alfombra que vayan a formar.

Ensueño de mi vida, mi ardiente vivo anhelo, Entonces nada importa me pongas en olvido.
Raymond M. Salvador, Ed.D. ¡Salud te grita el alma que pronto va a partir!
¡Salud! Ah, que es hermoso caer por darte vuelo,
Tu atmósfera, tu espacio, tus valles cruzaré.
Vibrante y limpia nota seré para tu oído,
ASDS Morir por darte vida, morir bajo tu cielo, Aroma, luz, colores, rumor, canto, gemido,
Y en tu encantada tierra la eternidad dormir. Constante repitiendo la esencia de mi fe.

Juliet A. Magallanes, Ed.D. Si sobre mi sepulcro vieres brotar un día Mi patria idolatrada, dolor de mis dolores,
Querida Filipinas, oye el postrer adiós.
CID Chief Entre la espesa yerba sencilla, humilde flor,
Acércala a tus labios y besa al alma mía, Ahí te dejo todo, mis padres, mis amores.
Y sienta yo en mi frente bajo la tumba fría, Voy donde no hay esclavos, verdugos ni opresores,
De tu ternura el soplo, de tu hálito el calor. Donde la fe no mata, donde el que reina es Dios.
Florencio R. Caballero, DTE
EPS-LRMDS Deja a la luna verme con luz tranquila y suave, Adiós, padres y hermanos, trozos del alma mía,
Amigos de la infancia en el perdido hogar,
Deja que el alba envíe su resplandor fugaz,
Deja gemir al viento con su murmullo grave, Dar gracias que descanso del fatigoso día;
Sandy R. Albarico Y si desciende y posa sobre mi cruz un ave,
Deja que el ave entone su cántico de paz.
Adiós, dulce extranjera, mi amiga, mi alegría,
Adiós, queridos seres, morir es descansar.
EPS-Science
Dr. Jose Rizal

15

JOSE RIZAL