EARTH AND SPACE- science 10 -1st quarter

learning materials

1. EARTH AND SPACE First Quarter

2. Volcano and its Relation to Plate Tectonics

3. LAYERS OF THE EARTH

4. Four Distinct Layers of the Earth

5. Aside from the three layers of the earth, there are still other layers of the earth that is worth mentioning. There is a layer called the lithosphere which includes the crust and the upper mantle . This is the rigid layer of the earth and measures about 100 kilometers.

6. The other one is the asthenosphere found in the mantle layer. It is a soft, weak layer that facilitates a small amount of melting and makes it capable of flowing. This property of the asthenosphere facilitates the movement of the lithospheric plates.

7. LITHOSPHERE

8. It is the rigid outer layer of the earth. It has an average thickness of about 75km to 100km. It comprises a number of plates. The motion of the lithospheric plate is known as the tectonic plate . It moves very slowly but constantly. The Earth’s lithosphere consists of layers of the crust and the upper part of the mantle. LITHOSPHERE

9. The lithosphere (solid part of the Earth) is composed of three major layers, the crust (outermost layer), the mantle (the middle layer), and the core (the innermost layer).

10. The topmost part of the lithosphere consists of crust . This material is cool, rigid, and brittle. Two types of crust can be identified: oceanic crust and continental crust

11. OCEANIC CRUST CONTINENTAL CRUST The continental crust is composed mostly of granite that's why it is less dense as compared to oceanic crust. The oceanic crust consists primarily of volcanic lava rock called basalt making it denser as compared to continental crust. The oceanic crust is thin and measures between 5 to 10 kilometers thick. The continental crust is 20 to 70 kilometers thick and composed mainly of lighter granite. oceanic crust is formed by magma when a volcanic eruption occurs underwater Continental crusts are formed through a volcanic eruption. Both of these types of crust are less dense than the rock found in the underlying upper mantle layer.

12. OCEANIC CRUST CONTINENTAL CRUST Oceanic crust is younger than the continental crust as the oldest age for this type is around 200 million years old compared to the four-billion-year-old continental crust. The oceanic crust has a limited lifespan because when it encounters continental crust, it is pushed down due to the subduction process. The continental crust is the layer of igneous, sedimentary, and metamorphic rocks that form the landmasses and the areas of shallow seabed close to the shore called the continental shelves. This layer is called sial because its bulk composition is rich in aluminum and silicates. The oceanic crust is the uppermost of the oceanic portion of the tectonic plates. It is sometimes called sima because it is richer in magnesium and silicate minerals.

13. Basalt and Granite Rocks

14. Plate Tectonic Theory It was Alfred Wegener , an Austrian climatologist, who first noted the theory on the movement of the Earth’s land masses which is known today as the modern Plate Tectonic Theory (Oskin, 2017). This theory states that the Earth’s crust comprises several broken plates that continuously move away, past, or toward each other.

15. Convection Cell

16. Theories on the movement of the lithosphere: Continental Drift theory (Alfred Wegener) (Oskin, 2017) This theory states that the Earth was once composed of only one supercontinent called Pangaea . Through time, this supercontinent split into two sub-continents, Laurasia and Gondwanaland.

17. 2. Seafloor Spreading Theory - Proposed by Harry Hess of Princeton University - States that the seafloor continuously spreads, and the extra crust gets recycled into the mantle. 3. Plate Tectonics Theory - States that the crust is composed of plates that move either towards, away, or past each other. - The modern version of the Continental Drift Theory of Alfred Wegener

18. Seafloor spreading theory and plate tectonics theory

19. How fast are the tectonic plates moving Earth’s land masses move toward and away from each other at an average rate of about 1.5 centimeters (0.6 inches) a year. That’s about the rate at human toenails grow! 

20. MAJOR LITHOSPHERIC OR TECTONIC PLATES

21. Lithospheric Plates Lithospheric plates are regions of Earth's crust and upper mantle that are fractured into plates that move across a deeper plasticine mantle.

22. Lithospheric Plates Earth's crust is fractured into 13 major and approximately 20 total lithospheric plates. Each lithospheric plate is composed of a layer of oceanic crust or continental crust superficial to an outer layer of the mantle. Lithospheric plates move on top of the asthenosphere (the outer plastically deforming region of Earth's mantle).

23. Pacific Plate This is the largest tectonic plate covering more than 103 million square kilometers and is underneath the Pacific Ocean. African Plate This plate covers 61, 300, 000 km2 of the African continent, some parts of the Atlantic Ocean and the Mediterranean Sea.

24. Eurasian Plate This plate is covering most of the area in Europe and Russia of about 67, 800, 000 km2. South American Plate This plate covers some regions of the Atlantic Ocean and the entire South American continent of about 43, 600, 000 km2.

25. Indo-Australian Plate This contains a huge part of the Australian continent, Indian subcontinent, and the surrounding ocean of the Australian continents of about 58, 900, 000 km2. North American Plate This plate extends 75, 900, 000 km2 from the North Pole to Siberia. This plate covers North America, some portions of the Atlantic Ocean and the Arctic Ocean, Greenland and the Bering Sea.

26. Antarctic Plate This covers the continents in Antarctica and the Southern Ocean of about 60, 900, 000 km2.

27. MINOR TECTONIC PLATES

28. The Philippine Sea Plate or the Philippine Plate is a 5, 500, 000 km 2 tectonic plate comprising of oceanic lithosphere that lies beneath the Philippine Sea, in the eastern part of the Philippines. Between the Pacific and Eurasian plates The Nazca Plate is an oceanic tectonic plate located in the eastern part of the Pacific Ocean. The biggest plate in between the South American and Pacific plates.

29. The Caribbean Plate is an oceanic tectonic plate underlying in Central America and the Caribbean Sea. It measures about 15. 600, 000 km2. The Arabian Plate is a 5, 000, 000 km2 tectonic plate in the eastern and northern hemispheres and one of the continental plates that have been moving northward in recent geological history colliding with the Eurasian Plate.

30. The Scotia Plate is a 1, 600, 000 km2 tectonic plate on the edge of the South Atlantic and the Southern Ocean. A small plate underneath the South American plate The Cocos Plate is a 2, 900, 000 km2 young oceanic plate beneath the Pacific Ocean. shares borders with the Pacific, Nazca and North American and Caribbean plates

31. The Juan de Fuca Plate is a 250, 000 km2 tectonic plate generated from the Juan de Fuca Ridge that is subducting under the northerly portion of the western side of the North American Plate. The  Indian Plate  (or  India Plate ) is a  minor tectonic plate  straddling the  equator  in the  Eastern Hemisphere . Originally a part of the ancient continent of  Gondwana , the Indian Plate broke away from the other fragments of Gondwana  100  million years ago and began moving north .

32. Activity #2: Identify the lithospheric plates of the Earth