(The Earth,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Science grade 10

1. GOOD MORNING Presented By: Sir Ken

2. ATTENDANCE

3. RECAP

4. CHEKING OF ASSIGNMENTS

5. CHEKING OF ASSIGNMENTS

6. REVIEW

7. Objectives: Describe the possible causes of plate movement Recognize the process of convection

8. Lesson 2 The Earth’s Mechanism

9. The Earth’s History Geology - Deals with the study of different processes, events, and history of the earth. EX: Landslides, Earthquakes, Floods, and Volcanic Eruptions. Stratigraphic column, to describe the vertical rocks units in a particular area that shows a sequence of sedimentary rocks. ( Limestone, chalk, clay, sandstone, coal and so on.

10. Pangea or Pangea, a supercontinent which according to the New World Encyclopedia, is thought to have existed during the Paleozoic and Mesozoic Eras,

11. Precambrian - This is the eon in the geologic time scale when life started. Paleozoic -  Is also known as the Age of the Dinosaurs. The Paleozoic Era is literally the era of “old life. Mesozoic - Was the "Age of Reptiles. Cenozoic - means 'recent life. ' During this era, plants and animals look most like those on Earth today.

12. Convection Current- Refers to transfer of heat by the mass movements and it is the driving force behind the movement of tectonics ( Example: boiling water) Asthenosphere - is the upper layer of the earth mantle lying beneath the lithosphere where in convection is though to occur.

13. Theory of Plate Tectonics - The Crust is broken up into giant slabs - ( Tectonic comes from Greek word Tektonikos meaning to build.) - This theory resemble a jigsaw puzzle. - Significant cause of many geological features on the surface of the Earth.

14. The Continental Drift Theory - Alfred Wegener, A German meteorologist proposed the Theory of Continental Drift - The Earth was made up of a single supercontinent through most of geologic time that eventually separated and drifted apart, forming into the seven continents.

15. Wegener first thought of this idea by noticing that the different large landmasses of the Earth almost fit together like Jigsaw Puzzle

16. Aside from these observations, Wegener Also, believed that the similarity of fossils in different continents, as well the

17. Seafloor Spreading Theory By ( Harry H. Hess) - As magma cools, it is pushed away from the flanks of the ridges. The spreading creates a successively younger ocean floor, and the flow of the material is thought to bring about migration, or drifting apart; of the continents. 3 results of seafloor spreading Oceanic trenches - are steep depressions in the deepest parts of the ocean [where old ocean crust from one tectonic plate is pushed beneath another plate, raising mountains, causing earthquakes, and forming volcanoes on the seafloor and on land. Oceanic ridges - Any of several continuous submarine mountain chains rising from the ocean floor Rift Valley - is a lowland region that forms where Earth's tectonic plates move apart, or rift

18. Work Activity: Answer page: 19 Let Check