Lesson 2 Earth's Interior...........pptx

.......

1. THE EARTH’S INTERIOR Prepared by: Renlie Jane Pascua- Pedronan

2. Learning Competency The learners demonstrate an understanding of geologic processes that occur within the Earth.

3. Learning Competency The learners explain why the Earth’s interior is hot ( S11/12ES-IIb-c-23 ).

4. Learning Objectives Objectives: Describe the properties of the layers of the Earth. Tell the composition of the layers of the Earth.

5. Studying the Earth’s Interior Scientists tried to explore and study the interior of the Earth. Yet, until today, there are no mechanical probes or actual explorations done to totally discover the deepest region of the Earth.

6. How did they know? The Earth is made up of three layers: the crust, the mantle, and the core . The study of these layers is mostly done in the Earth’s crust since mechanical probes are impossible due to the tremendous heat and very high pressure underneath the Earth’s surface.

7. The Solid Earth geology - the study of the structure, history, and activity of the solid Earth, including its interactions with the atmosphere, hydrosphere, cryosphere, and biosphere solid Earth contains four major zones : the core (which is divided into inner and outer zones), the (upper and lower) mantle , the asthenosphere , and the lithosphere

8. Geology Forces that wear away mountains and every other feature on the Earth’s surface. Forces that shape the Earth’s surface by building up mountains and landmasses. Constructive Forces Destructive Forces

9. OUR HOME PLANET, EARTH Our Earth is about average among the planets in the Solar System, in many respects: largest and most massive of the four terrestrial planets, but smaller and less massive than the four giant, or Jovian, planets third in distance from the Sun among the four terrestrial planets has a moderately dense atmosphere ; 90 times less dense than that of Venus but 100 times denser than that of Mars

10. OUR HOME PLANET, EARTH Earth is also unique in many respects: the only planet with liquid water on its surface. the only one having a significant (21%) proportion of molecular oxygen to our best current knowledge, the only planet in the solar system having living organisms the only terrestrial planet having a moderately strong magnetic field the only terrestrial planet having a large satellite

11. OUR HOME PLANET, EARTH

12. The Solid Earth the outer zones is not uniform and fixed over the surface of the Earth, but shows much variability with position and time. The field of plate tectonics deals with this spatial and temporal variability. Geological phenomena such as earthquakes, volcanoes, and continental drift are accounted for by plate tectonics.

13. Earth's Interior

14. Exploring the Earth’s Interior with a Hard-Boiled Egg

15. Bring the following: (Individual) hardboiled egg/s bread knife used paper/newspaper to work on

16. Activity 1C: Hard Boiled Earth PROCEDURE: 1. Prepare the materials. (hardboiled egg, bread knife, used paper to work on) 2. Place used paper or newspaper on your working area. Cut the egg into halves using a knife or a cutter . 3. Draw the appearance of the cut hard-boiled egg.

17. Procedure: Using qualitative observation , describe the parts of the egg from the outermost to the innermost by completing the table. Write your answer on a piece of paper/ short bond paper. PARTS OF THE EGG DECSRIPTION EQUIVALENT TO THE EARTH’S LAYER DESCRIPTION                        

18. Guide Questions: 1. How many layers does a hard-boiled egg have? 2. Which is the largest part? The thinnest? 3. Compare the parts of the egg to the model of the earth. 4. Aside from the hard-boiled egg, what other things can you compare to the earth’s interior layers?

19. CRUST

20. What is the Earth's Crust? The Earth's crust is the solid, rocky outer layer, covering the entire planet. It is relatively thin compared to other layers. The Earth's crust is where all life forms exist, providing the environment for plants, animals, and humans.

21. The Crust thinnest and the outermost layer of the Earth that extends from the surface to about 32 kilometers below Continental Oceanic

22. Types of Crust: Continental and Oceanic 1 Continental Crust This type of crust is thicker and less dense, forming the continents and landmasses. It's predominantly made of granitic rocks.

23. Continental mainly made up of silicon, oxygen, aluminum, calcium, sodium, and potassium mostly 35-40 kilometers found under land masses made of less dense rocks such as granite

24. Types of Crust: Continental and Oceanic 2 Oceanic Crust This crust is thinner and denser, found beneath the oceans. It's composed mainly of basaltic rocks and is younger than continental crust.

25. Oceanic oceanic crust is around 7-10 kilometers thick which its average thickness is 8 kilometers . found under the ocean floor made of dense rocks such as basalt heavier than the continental crust.

26. Elements in the Crust

27. Moho Discontinuity While studying the speed of earthquake waves, Croatian geophysicist Andrija Mohorovičić discovers a boundary between Earth's crust and mantle , which becomes known as the Mohorovičić , or Moho, Discontinuity.

28. Subduction Zones 1 Oceanic-Continental Denser oceanic plate subducts beneath continental plate. 2 Oceanic-Oceanic Denser oceanic plate subducts under another oceanic plate. 3 Continental-Continental Two continental plates collide, resulting in mountain ranges.

29. Continental Rift Zones Continental Separation Continents split apart due to tectonic forces. Volcanic Activity Magma rises to the surface, creating volcanoes and associated features. Formation of New Ocean Over time, the rift valley can widen and fill with water, forming a new ocean basin.

30. Geological Processes Shaping the Crust 1 Volcanism Volcanic eruptions, a result of molten rock (magma) rising to the surface, can create new landforms, like islands and mountains. 2 Earthquakes Sudden movements along fault lines release energy in the form of seismic waves, causing the ground to shake. 3 Weathering and Erosion These processes break down rocks and transport them, shaping the Earth's surface over time. 4 Mountain Formation The collision of tectonic plates can create mountains, folds, and faults, shaping the landscape.

31. Geological Features of the Earth's Crust Canyons Deep, narrow gorges carved by rivers over millions of years. Mountains Elevated landforms created by tectonic forces or volcanic activity. Ocean Trenches Deepest parts of the ocean, formed at convergent plate boundaries where one plate subducts beneath another.

32. Significance and Importance of the Earth's Crust Home to Life The Earth's crust provides the environment for all living organisms, supporting diverse ecosystems. Natural Resources The Earth's crust contains valuable natural resources, including minerals, fuels, and water. Understanding Our Planet Studying the Earth's crust helps us understand geological processes and the history of our planet. Protection The Earth's crust provides protection from the harsh conditions of space, creating a safe environment for life.

33. The Earth's Mantle

34. The Mantle Beneath the crust is the mantle extends to about 2900 kilometers from the Earth’s surface about 80% of the Earth’s total volume about 68% of its total mass mainly made up of silicate rocks and contrary to common belief, is solid , since both S-waves and P-waves pass through it

35. The Mantle mostly made of the elements silicon, oxygen, iron and magnesium lower part of the mantle consists of more iron than the upper part l ower mantle is denser than the upper portion temperature and the pressure increase with depth high temperature and pressure in the mantle allows the solid rock to flow slowly

36. Upper Mantle This layer, extending from the crust down to around 410 km, is composed of peridotite, a dense, dark-colored rock rich in magnesium and iron. Lower Mantle The lower mantle, stretching from 410 km to the core, is hotter and denser, with the mineral composition shifting due to intense pressure. Composition and Structure of the Mantle

37. Heat Transfer and Convection Currents Heat Source The Earth's core generates immense heat, primarily through radioactive decay of elements. Mantle Flow This heat creates convection currents, where hot, less dense rock rises and cooler, denser rock sinks, creating a circular flow. Driving Force These currents are a fundamental force driving plate tectonics, shaping Earth's surface.

38. Mantle Plumes and Hotspot Volcanism 1 Upwelling Plumes Mantle plumes are narrow columns of abnormally hot rock that rise from deep within the mantle. 2 Volcanic Activity When these plumes reach the surface, they can create hotspots, regions of intense volcanic activity, often forming island chains like Hawaii. 3 Geochemical Signatures Volcanic eruptions from hotspots often produce unique geochemical signatures, helping scientists understand the composition of the deep mantle.

39. Plate Tectonics and the Role of the Mantle 1 Mantle Convection The mantle's convection currents provide the driving force for plate tectonics. 2 Plate Movement The plates, riding on the moving mantle, interact with each other, causing earthquakes, volcanic eruptions, and mountain formation. 3 Earth's Dynamics The interplay between the mantle and tectonic plates is responsible for the Earth's dynamic surface, shaping continents, oceans, and landscapes.

40. Mantle Mineralogy and Phase Changes Pressure Effects The immense pressure within the mantle causes minerals to transform into denser phases, changing their crystal structure. Phase Transitions These phase transitions play a crucial role in the physical and chemical properties of the mantle, affecting its flow and the behavior of seismic waves. Mineral Research Studying mantle minerals and their phase changes helps us understand the evolution of the Earth and its internal processes.

41. Implications for Earth's Evolution and Future Volcanic Activity The mantle influences volcanic eruptions, which release gases and minerals, impacting Earth's atmosphere and climate over time. Earthquakes The mantle's movement drives plate tectonics, causing earthquakes that shape landscapes and release energy within the Earth. Mountain Building The collision of tectonic plates, driven by mantle convection, results in the formation of mountain ranges, shaping Earth's topography.

42. The Earth's Core

43. What is the Earth's Core? Inner Core The solid, innermost part of the Earth, primarily composed of iron with a temperature of about 5,200°C (9,392°F). Outer Core A liquid layer of iron and nickel that surrounds the inner core, with temperatures ranging from 4,500°C to 5,500°C (8,132°F to 9,932°F).

44. The Core 2000-5000 o C core is subdivided into two layers : the inner the outer core.

45. Core Outer Core The outer core is a liquid layer composed primarily of iron and nickel. It is responsible for generating Earth's magnetic field. Inner Core The inner core is a solid sphere of iron and nickel, despite the extreme temperatures. The immense pressure at the core causes the iron to solidify.

46. Outer Core 2900 kilometers bel ow the Earth’s surface 2250 kilometers thick made up of iron and nickel temperature reaches up to 2000 o C at this very high temperature, iron and nickel melt

47. Outer Core Aside from seismic data analysis , the Earth’s magnetic field strengthens the idea that the Earth’s outer core is molten/liquid mainly made up of iron and nickel moving around the solid inner core , creating Earth’s magnetism

48. The Inner Core made up of solid iron and nickel and has a radius of 1300 kilometers about 5000 o C extreme temperature could have molten the iron and nickel but it is believed to have solidified as a result of pressure freezing , which is common to liquids subjected under tremendous pressure

49. The Inner Core Aside from the fact that the Earth has a magnetic field and that it must be iron or other materials which are magnetic in nature , the inner core must have a density that is about 14 times that of water. Average crustal rocks with densities 2.8 times that of water could not have the density calculated for the core . So iron , which is three times denser than crustal rocks , meets the required density.

50. Clues that the inner core and the outer core are made up of iron Iron and nickel are both dense and magnetic. overall density of the earth is much higher than the density of the rocks in the crust suggests that the inside must be made up of something denser than rocks

51. Clues that the inner core and the outer core are made up of iron Meteorite analysis have revealed that the most common type is chondrite . Chondrite contains iron, silicon, magnesium and oxygen ; some contains nickel . The whole earth and the meteorite roughly have the same density, thus the Earth’s mantle rock and a meteorite minus its iron, have the same density.

52. Structure of the Earth's Core 1 Inner Core The inner core is solid due to immense pressure, despite its high temperature. 2 Outer Core The outer core is liquid, allowing for the flow of molten iron, which generates Earth's magnetic field.

53. Composition of the Earth's Core Element Percentage Iron 88% Nickel 5.5% Sulfur 4.5% Silicon 1% Oxygen 0.5%

54. Importance of the Earth's Core 1 Magnetic Field The Earth's magnetic field protects us from harmful solar radiation, allowing life to thrive. 2 Plate Tectonics The Earth's core drives plate tectonics, which shapes continents and creates mountains, volcanoes, and earthquakes.

55. How the Earth's Core Generates Magnetic Field Convection Currents Heat from the Earth's core creates convection currents in the liquid outer core. Electric Currents The movement of molten iron generates electric currents, which in turn create a magnetic field.

56. Dynamics of the Earth's Core Seismic Waves Seismic waves travel through the Earth's core, providing scientists with valuable information about its structure and composition. Magnetic Reversals The Earth's magnetic field periodically reverses, with the north and south poles switching places.

57. Exploring the Earth's Core Drilling Scientists have drilled deep into the Earth's crust, but reaching the core remains a significant technological challenge. Seismology By studying seismic waves, scientists can infer the structure and composition of the Earth's core. Satellite Data Satellites provide valuable data about the Earth's magnetic field, which is generated by the core.

58. Did you know? The deepest mine in the world, the gold mine in South Africa, reaches a depth of 3.8km . But... You would have to travel more than 1,600 times that distance-over 6000km-to reach the earth’s center.

59. The Composition of the Earth’s Interior

60. DENSITY AND TEMPERATURE VARIATION IN DEPTH

61. Remember: The ability of the asthenosphere to flow slowly is termed as plasticity. crust a nd the uppermost part of the mantle form a relatively cool, outermost rigid shell called lithosphere ( Gk. lithos means “stone”) and is about 50 to 100 kilometers thick

62. Remember: Beneath the lithosphere lies the soft, weak layer known as the asthenosphere ( Gk. a sthenes means “weak”) made of hot molten material, about 300 – 800 o C upper 150 kilometers has a temperature enough to facilitate a small amount of melting, and make it capable to flow facilitates the movement of the lithospheric plates lithosphere , with the continents on top of it, is being carried by the flowing asthenosphere.

63. Seismic Waves S eismic waves from earthquakes are used to analyze the composition and internal structure of the Earth . What are seismic waves? Wheel of Names | Random name picker

64. Seismic waves Earthquake is a vibration of the Earth produced by the rapid release of energy. This energy radiates in all directions from the focus in the form of waves called seismic waves.

65. Earthquake: Seismic Wave Wave Direction Fault Epicenter Focus https:// ds.iris.edu/seismon/swaves/index.php

66. Types of Seismic Wave Surface waves Body Waves

67. Surface Waves can only travel through the surface of the Earth arrive after the main P and S waves They are slower-moving than body waves but are much larger and therefore more destructive. They travel only through solid media.

68. Types of Surface Waves

69. Types of Surface Waves

70. Rayleigh Waves named after John William Strutt , Lord Rayleigh, who mathematically predicted the existence of this kind of wave in 1885 wave rolls along the ground just like a wave rolls across a lake or an ocean up and down or side-to-side similar to the direction of the wave’s movement shaking felt from an earthquake

71. Rayleigh Waves

72. Love Waves named after A.E.H. Love , a British mathematician who worked out the mathematical model for this kind of wave in 1911 . faster than Rayleigh wave it moves the ground in a side-to-side horizontal motion, like that of a snake’s causing the ground to twist c ause the most damage to structures during an earthquake.

73. Love Waves

74. B ody waves can travel through the Earth’s inner layers they are used by scientists to study the Earth’s interior higher frequency than the surface waves

75. Body waves 2 types P-Waves (Primary waves) S-waves (Secondary waves)

76. P-waves (Primary) is a pulse energy that travels quickly through the Earth and through liquids travels faster than the S-wave it reaches a detector first

77. P-waves (Primary) compressional waves, travel by particles vibrating parallel to the direction the wave travel move backward and forward as they are compressed and expanded they travel through solids, liquids and gases

78. S-waves (Secondary/Shear) pulse energy that travels slower than a P-wave through Earth and solids Move as shear or transverse waves, and 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

79. S-waves (Secondary/Shear) cannot travel through any liquid medium led seismologists to conclude that the outer core is liquid

80. Seismic Waves movement

81. Seismic Waves and the Study of the Mantle Type Behavior Information P-waves Compressional, travel through solids and liquids Provide information about the overall structure and density of the mantle. S-waves Shear, travel only through solids Reveal the presence of solid rock, helping determine the depth and composition of different mantle layers.

82. Seismic Waves: Interior Part

83. Remember: P-waves are detected on the other side of the Earth opposite the focus . A shadow zone from 103° to 142° exists from P-waves Since P-waves are detected until 103°, disappear from 103° to 142°, then reappear again, something inside the Earth must be bending the P-waves

84. Remember: existence of a shadow zone , according to German seismologist Beno Gutenberg ( ɡu ː t ən bɛʁk ), could only be explained if the Earth contained a core composed of a material different from that of the mantle causing the bending of the P-waves To honor him, mantle–core boundary is called Gutenberg discontinuity

85. Remember: From the epicenter, S-waves are detected until 103° , from that point, S- waves are no longer detected S-waves do not travel all throughout the Earth’s body knowing the properties and characteristics of S-waves (that it cannot travel through liquids ), and with the idea that P-waves are bent to some degree, this portion must be made of liquid , thus the outer core

86. Remember: 1936, the innermost layer of the Earth was predicted by Inge Lehmann , a Danish seismologist discovered a new region of seismic reflection within the core Earth has a core within a core

87. Remember: the outer part of the core is liquid based from the production of an S wave shadow and the inner part must be solid with a different density than the rest of the surrounding material size of the inner core was accurately calculated through nuclear underground tests conducted in Nevada. e choes from seismic waves provided accurate data in determining its size

88. "Exploring Earth’s interior reveals a history written in stone, a record of transformations that continue to shape our future."