plate-tectonics-power-point-1.ppt-agham.

Science notes

1. EARTH AND SPACEEARTH AND SPACE
Our country is blessed with so many Our country is blessed with so many
land features such as mountains and land features such as mountains and
volcanoes. These features can be volcanoes. These features can be
sources of different minerals or can sources of different minerals or can
be used for agricultural purposes.be used for agricultural purposes.

2. For example, we have the majestic and For example, we have the majestic and
world renowned Mayon Volcano, because world renowned Mayon Volcano, because
of its activity, it produces fertile slopes and of its activity, it produces fertile slopes and
plains which are used by the locals to grow plains which are used by the locals to grow
crops. Also, found in the northeastern coast crops. Also, found in the northeastern coast
of Luzon, we have the Sierra Madre of Luzon, we have the Sierra Madre
mountain range which is home to many mountain range which is home to many
endemic species of flora and fauna.endemic species of flora and fauna.

3. SIERRA MADRESIERRA MADRE
•Is the longest mountain range in the Is the longest mountain range in the
Philippines, running from the northern Philippines, running from the northern
part of Luzon down to its southern end.part of Luzon down to its southern end.
•It has unique ecological, cultural, and It has unique ecological, cultural, and
geological significance. geological significance.

4. Have you ever wounder Have you ever wounder
why our country is why our country is
endowed with these kind endowed with these kind
of geologic features?of geologic features?

5. We will study thoroughly the We will study thoroughly the
framework that will enable us to framework that will enable us to
understand how and why several understand how and why several
features of the earth continuously features of the earth continuously
change. This is what we callchange. This is what we call
““PLATE TECTONICS”.PLATE TECTONICS”.

6. Plate TectonicsPlate Tectonics
The theory that the Earth’s outermost layer is The theory that the Earth’s outermost layer is
fragmented into a dozen or more large and fragmented into a dozen or more large and
small plates that move relative to one another small plates that move relative to one another
as they ride on top of hotter, more mobile as they ride on top of hotter, more mobile
material.material.

7. What Are Tectonic Plates?What Are Tectonic Plates?
•A plate is a large, rigid slab of
solid rock.
–Plates are formed from the
lithosphere: the crust and the
upper part of the mantle.
•The plates “float” on the slowly
flowing asthenosphere: the
lower part of the mantle.
•The plates include both the
land and ocean floor.
•The Mohoriovicic discontinuity
or Moho is the boundary
between the crust and the
mantle.

8. Earth’s PlatesEarth’s Plates

9. Plate BoundariesPlate Boundaries

10. Triangulation MethodTriangulation Method
A method used to locate the A method used to locate the
epicenter of an earthquake. epicenter of an earthquake.
It uses 3 recording stations.It uses 3 recording stations.

11. If we have at least 3 recording If we have at least 3 recording
stations that can tell how far away stations that can tell how far away
from them the earthquake occurred, from them the earthquake occurred,
the epicenter can be determined the epicenter can be determined
using the triangulation method. It using the triangulation method. It
uses distance information from 3 uses distance information from 3
seismic stations to locate the seismic stations to locate the
epicenter of an earthquake.epicenter of an earthquake.

12. The 3 circles will intersect The 3 circles will intersect
at one point that locates the at one point that locates the
earthquake.earthquake.

13. To compute the distance of the To compute the distance of the
epicenter from each of the stations epicenter from each of the stations
using the formula:using the formula:
d = Td/ 8 seconds x 100 kmd = Td/ 8 seconds x 100 km
Where: d = distanceWhere: d = distance
Td= time difference in the arrival Td= time difference in the arrival
time of P and S wave (seconds) time of P and S wave (seconds)

14. Different Types of Different Types of
BoundariesBoundaries

15. Different Types of Different Types of
BoundariesBoundaries
•Convergent boundaries come together
–Places where crust is destroyed as one plate
dives under another
•Divergent boundaries spread apart
–Places where new crust is generated as the
plates pull away from each other
–New crust is created from magma pushing
up from the mantle
•Transform boundaries slide against
each other
–Places where crust is neither produced nor
destroyed as the plates slide horizontally
past each other

20. Oceanic-Continental ConvergenceOceanic-Continental Convergence
•The oceanic plate subducts under the continental plate because it has lower
density.
 
•The oceanic Nazca Plate is being subducted under the continental part of the
South American Plate.
•The South American Plate is being lifted up, creating the Andes mountains.
•Strong, destructive earthquakes and rapid uplift of mountain ranges are
common in this region.
•These earthquakes are often accompanied by uplift of the land by as much as
a few meters.
•Mount Saint Helens is along the subduction zone of the Juan de Fuca plate
(an oceanic plate) and the North American plate (a continental plate).
Oceanic – Continental Convergence

21. What will happen to the Oceanic Crust as it continues to move downward? Why?
What do you call the molten material?
What is formed on top of Continental crust?
As the plates continue to grind past each other, what geologic event could take
place?

22. Oceanic-Oceanic ConvergenceOceanic-Oceanic Convergence
•When two oceanic plates converge, one
is usually subducted under the other.
•An older oceanic plate is colder,
therefore more dense and less buoyant,
and will subduct under a younger,
hotter, less dense, and more buoyant
oceanic plate.
•In the process, a trench is formed.
–The deepest trenches in the oceans
are along oceanic-oceanic
subduction zones (i.e., the Marianas
Trench in the Pacific, which is
deeper than Mt. Everest is high).
•Subduction in oceanic-oceanic plate
convergence can result in the formation
of volcanoes.
•Examples of oceanic-oceanic
convergence are the arcuate chains of
islands in the southwest Pacific, Japan,
and the Aleutian Islands.
Oceanic – Oceanic Convergence

23. What are the geologic process/events that will occur because of this plate
movement?
What geologic features might form at the surface of plate B?
If the edge of Plate B suddenly flicks upward, a large amount of water may be
displaced. What could be formed at the surface of the sea?

24. Tsunami is the Japanese term for “harbor wave,” is a series of ocean
waves with very long wavelengths caused by large-scale disturbances of
ocean.

25. Tsunami is the Japanese term for “harbor wave,” is a series of ocean
waves with very long wavelengths caused by large-scale disturbances of
ocean.

26. Continental-Continental Continental-Continental
ConvergenceConvergence
Continental – Continental Convergence
• When two continents meet head-on,
neither is subducted because the
continental rocks are relatively light and, like
two colliding icebergs, resist downward
motion.
• Instead, the crust tends to buckle and be
pushed upward or sideways.
The collision between the Indian and
Eurasian plates has pushed up the
Himalayas and the Tibetan Plateau.

27. Continental-Continental Continental-Continental
ConvergenceConvergence
•50 million years ago, the
Indian Plate collided into the
Eurasian Plate.
•After the collision, the slow
continuous convergence of the
two plates over millions of
years pushed up the Himalaya
and the Tibetan Plateau to
their present heights.
•The Himalaya form the highest
continental mountains in the
world.

28. DivergenceDivergence
• Divergent boundaries occur
along spreading centers where
plates are moving apart and new
crust is created by magma
pushing up from the mantle.
• The Mid-Atlantic Ridge is a
divergent boundary.
• Sea-floor spreading over the
past 100 to 200 million years has
caused the Atlantic Ocean to grow
from a tiny inlet of water between
the continents of Europe, Africa,
and the Americas into the ocean
that exists today.

29. DivergenceDivergence
•Iceland is splitting along the Mid-Atlantic Ridge between the North
American and Eurasian Plates, as North America moves westward
relative to Eurasia.
•In East Africa, spreading processes have already torn Saudi Arabia
away from the rest of the African continent, forming the Red Sea.
•The actively splitting African Plate and the Arabian Plate meet in
what geologists call a triple junction, where the Red Sea meets the
Gulf of Aden.

32. TransformTransform
• The zone between two plates that
slide
past one another is called a
transform-fault boundary, or
transform boundary.
• These large faults connect two
spreading centers or connect
trenches.
• Most transform faults are found on
the ocean floor.

33. TransformTransform
•The San Andreas Fault is
one of the few transform
faults exposed on land.
– It connects the East
Pacific Rise, a divergent
boundary to the south, with
the Juan de Fuca Ridge, a
divergent boundary to the
north.
– Most earthquakes in
California are caused by
the accumulation and
release of strain as the two
plates slide past each
other.

34. Consequences of Plate TectonicsConsequences of Plate Tectonics
•Earthquakes and volcanic activity are linked to plate
tectonic processes.
•The Ring of Fire is the most seismically and volcanically
active zone in the world.

35. Consequences of Plate Consequences of Plate
TectonicsTectonics
The San Andreas Fault – a
transform fault
Aerial view of the area around Thingvellir, Iceland,
showing a fissure zone (in shadow) that is an on-land
exposure of the Mid-Atlantic Ridge. Right of the fissure,
the North American Plate is pulling westward away from
the Eurasian Plate (left of fissure).

36. Consequences of Plate Consequences of Plate
TectonicsTectonics
The Aleutian Islands, an island arc
The 1980 eruption of Mount
Saint Helens

37. Consequences of Plate Consequences of Plate
TectonicsTectonics
The convergence of the Nazca and South American Plates
has deformed and pushed up limestone strata to form
towering peaks of the Andes, as seen here in the
Pachapaqui mining area in Peru.
Helicopter view (in February 1994) of the active
lava lake within the summit crater of 'Erta 'Ale
(Ethiopia), one of the active volcanoes in the
East African Rift Zone.

38. ReferencesReferences
•Understanding Plate Motions. USGS.
http://pubs.usgs.gov/publications/text/unde
rstanding.html
•Plate Movement. OptIPuter Outreach.
http://education.sdsc.edu/optiputer/teacher
s/platemovement.html
•Plate Tectonics. The Way the Earth
Works. LHS GEMS, 2002.

39. What Drives Plate What Drives Plate
Tectonics?Tectonics?
•The slow movement of hot,
softened mantle lies below
rigid plates.
•The hot, softened rock in the
mantle moves in a circular
manner in a convection flow
– the heated, molten rock
rises to the surface,
spreads, and begins to cool,
and then sinks back down to
be reheated and rises again.

40. ..\CONVERGENT PLATE BOUNDARIES.mp4
..\..\Downloads\Explanation of divergent plate boundaries and
shield volcano's.mp4
k
..\..\Downloads\Transform Fault Boundaries_ Plates Sliding
Against Each Other.mp4

41. Movement Movement
of the of the
Plates Over Plates Over
TimeTime
Permian
248 million years ago
Triassic
206 million years ago
Jurassic
206 million years ago
Cretaceous
65 million years ago
Present Day

42. Progression Progression
of Indian of Indian
Land MassLand Mass

43. Assessment
1. Predict what geological
features could result out of
this plate boundary

44. Assessment
2. In a hot spot, Volcano A is on top of the mantle plum, Volcano B is 10
km farther from A while Volcano C is the farthest. What can you infer about
the ages of the volcanoes?
a. Volcano A is older than Cc. Volcano B is the youngest
b. Volcano B is the oldestd. Volcano B is younger than C
3. Right in the middle of an island, you can find a rift valley. What type of
plate boundary exists on that island?
a.Convergent b. Divergent c. normal fault d. transform fault

45. 4. Plates A and B shows a divergent boundary. If plate C is adjacent to both
plates and does not show any relative motion, what type of plate boundary is
present between A and C?

46. Assessment
5. What geologic event is most likely to happen at the given type of plate
boundary in number 4?
a.Earthquakeb. mountain formationc. rift valleyd. volcanic eruption
6. You were ask to locate the epicenter of the earthquake. Which correct
sequence of events should you follow?
i.Determine the difference in the arrival of P and S waves recorded from each
seismological stations
ii.Use the triangulation method to locate the center
iii.Obtain the data from 3 different stations
iv.Determine the distance of the epicenter from the station.
a. i, iii, ii, ivb. iii, i, iv, iic. iii, iv, i, iid. iv, ii, i, iii

47. Assessment
7. What do you expect to find parallel to a trench?
a.Hot spot b. ocean ridgec. rift valleyd. volcanic arc
A B C
8. Divergent a. Moving away from
each other
d. Earthquakes
9. Convergent b. Moving towards each
other
e. mountains,
volcanoes, trenches,
and earthquakes
10. Transform Fault c. Sliding past each
other
f. Rift valleys, oceanic
ridges, and earthquakes

48. 1.An S-wave zone is formed as
seismic waves travels through
the Earth’s body. Which of the
following statements does this
S-wave shadow zone
indicate?
a.The inner core is liquid
b.The inner core is solid
c.The mantle is solid
d.The outer core is liquid

49. 2. Why are there are no P-waves and S-waves received in the P-
wave shadow zone?
a.p-waves are absorbed and s-wave are refracted by Earth’s outer
core
b.p-waves are refracted and s-wave are absorbed by Earth’s outer
core
c.Both p-waves and s-waves are refracted by Earth’s outer core.
d.Both p-waves and s-waves are absorbed by Earth’s outer core.
3. What makes up the lithosphere?
a.Continental crust
b.Crust and the upper mantle
c.Oceanic crust and continental crust
d.Upper mantle

50. 4. Miners dig into the Earth in search for precious rocks and minerals. In
which layer is the deepest explorations made by miners?
a.Crust c. mantle
b.Inner core d. outer core
5. How do you compare the densities of the Earth’s crust, mantle, and
core?
a.The mantle is less dense than the core but denser than the crust.
b.The mantle is less dense than both core and crust.
c.The mantle is denser than the core but less dense than the crust.
d.The mantle is denser than both the core and the crust.

51. 6. The movement of the lithospheric plates is facilitated by a soft, weak,
and plastic-like layer. Which of the following layers is described in the
statement?
a.Asthenosphere c. lithosphere
b.Atmosphere d. mantle
7. Alfred Wegener is a German scientist who hypothesized that the Earth
was once made up of a single large landmass called Pangea. Which of
the following theories did Wegener propose?
a.Continental drift theory
b.Continental shift theory
c.Plate tectonics
d.Seafloor spreading theory

52. 8. If you are a cartographer, what will give you an idea that the continents
were once joined?
a.Ocean depth b. position of south pole
b.Shape of the continents d. size of Atlantic ocean
9. Which observation was NOT instrumental in formulating the hypothesis of
seafloor spreading?
a.Depth of the ocean b. identifying location of glacial deposits
b.Magnetization of oceanic crustd. thickness of seafloor sediments
10. As a new seafloor is formed at the mid-ocean ridge, the old seafloor
farthest from the ridge is destroyed. Which of the stated processes
describes how the oceanic crust plunges into the earth and destroyed at the
mantle?
a.Convection b. construction
c. Diversion d. subduction

53. 1.1.What are the different layers What are the different layers
of the Earth?of the Earth?
2.2.Why is there a need to study Why is there a need to study
the Earth’s layers?the Earth’s layers?
3.3.What do the shape of the What do the shape of the
continents tells us about their continents tells us about their
past?past?

54. STUDYING THE EARTH’S
INTERIOR
..\..\Downloads\Structure Of The Earth _ The Dr. Binocs Show _
Educational Videos For Kids.mp4

55. Seismic WavesSeismic Waves
The energy that The energy that
radiates in all radiates in all
directions from the directions from the
focusfocus
Two types:Two types:
1.1.Surface waves Surface waves
2.2.Body wavesBody waves
..\..\Downloads\SEISMIC WAVES _ Easy Physics Animation.mp4

56. Surface WavesSurface Waves
Two typesTwo types
1.1.Love WavesLove Waves
2.2.Rayleigh Rayleigh
WavesWaves
-can only travel through the surface of the Earth. They arrive after the
main P and S waves and are confined to the outer layers of the
waves.

57. Love wavesLove waves
-is named after A.E.H. Love, a British mathematician who
worked out the mathematical model for this kind of wave in
911.
- It is faster that Rayleigh wave and it moves the ground in
a side-to-side horizontal motion, like a snake causing the
ground to twist. That is why Love waves cause the most
damage to structure during an earthquake.
..\..\Downloads\Propagation of Seismic Waves_ Love waves.mp4

58. Rayleigh wavesRayleigh waves
-Named after John William Strutt, Lord Rayleigh, who
mathematically predicted the existence of this kind of
wave in 1885.
-A Rayleigh wave rolls along the ground just like a wave
rolls across a lake or ocean. Since it rolls, it moves the
ground either up and down or side-to-side similar to the
direction of the wave’s movement.
-Most of the shaking felt from earthquake is due to
Rayleigh wave.
n..\..\Downloads\Propagation of Seismic Waves_ Rayleigh waves.mp4

59. Body WavesBody Waves
Two typesTwo types
1.1.P-waveP-wave
2.2.S-waveS-wave
-Can travel through the Earth’s layer.
-Used by scientists to study the Earth’s interior
-They have higher frequency that surface waves

60. P-wavesP-waves
-P-wave (primary wave) is a pulse energy that travels
quickly through the Earth and through liquids.
-Travels faster than S-wave
-After an earthquake, it reaches the detector first.
-Also called compressional waves since they travel by
particles vibrating parallel to the direction of the wave
travel.
-They force the ground to move back and forward as
they are compressed and expanded.
-They travel through solids, liquids, and gases.
..\..\Downloads\Propagation of Seismic Waves_ P-waves.mp4

61. S-wavesS-waves
-Secondary wave is a pulse of energy that travels slower
than a p-wave through Earth and solids.
-Moves as shear or transverse waves, force the ground
to sway from side to side, in rolling motion that shakes
the ground back and forth perpendicular to the direction
of the waves.
-The idea that s-wave cannot travel through any liquid
medium led seismologists to conclude that the outer
core is liquid.
..\..\Downloads\Propagation of Seismic Waves_ S-waves.mp4

62. ..\..\Downloads\videoplayback.mp4

64. The Composition of the Earth’s Interior

65. The Crust The Crust
The crust is the thinnest and
the outermost layer of the
Earth that extends from the
surface to about 32 kilometers
below.
-Divided into two regions:
continental and oceanic crust.
-Continental crust is made up
of silicon, oxygen, aluminum,
calcium, sodium, and
potassium.
-Oceanic crust is found under
the ocean floor and is made of
dense rocks such as basalt.