G 7 geo ch-2 inside our earth full chapter week-2

class-7 geo ch-2 ncert

1. { 13 TH TO 18 TH JULY 2020} GRADE-7 GEOGRAPHY CHAPTER-2: INSIDE OUR EARTH

2. INTERIOR OF THE EARTH TYPES OF ROCKS ROCK CYCLE MINERALS

3. CHAPTER-2 INSIDE OUR EARTH CLASS -1 LEARNING OBJECTIVE FOR THIS CLASS Interior of the earth CRUST CORE MANTLE DATE: .07.2020

4. ABOUT THE EARTH The Earth, our homeland is a dynamic planet . It is constantly undergoing changes inside and outside.

5. INTERIOR OF THE EARTH Just like an onion, the Earth is made up of several concentric layers with one inside another. E A R TH ONI O N

6. INTERIOR OF THE EARTH C R U S T LITHOSPHERE MANTLE CORE-MANTLE B O U N D A R Y OUTER CORE INNER CORE

7. CRUST The uppermost layer over the earth’s surface is called the CRUST . It is the thinnest of all the layers .

8. DID YOU KNOW? The Crust forms only 0.5 per cent of the volume of the earth, 16 per cent consists of the mantle and 83 per cent makes the core. CRUST

9. THE CRUST

10. Continental Crust and Oceanic Crust Crust is about 35 km. on the continental masses and only 5 km.on the ocean floors. The oceanic crust mainly consists of silica andmagnesium; it is therefore called sima ( si -silica and ma- magnesium). The main mineral constituents of thecontinental mass are silica and alumina . It is thus called sial (si-silica and al-alumina). CONTINENTAL CRUST C ON T INENT O C E AN O C E A N IC CRUST

11. Oceanic and Continental Crust Oceanic Crust is thin but very dense .

12. Activity: Earth's Laye rs How are the earth’s layers similar to an egg? Shell= ? Egg white= ? Yolk= ?

13. MANTLE Just beneath the crust is the MANTLE which extends up to a depth of 2900 km below the crust. MA N T L E C R U S T

14. THE MANTLE MANTLE

15. THE CORE

16. INTERESTING FACTS The deepest mine in the world, is in South Africa. It is about 4 km. deep. In search for oil, engineers have dug a hole about 6 km.deep. To reach to the centre of the earth (which is not possible!) you will have to dig a hole 6000 km. deep on the ocean floor.

17. Quiz time The thinnest layer of the earth is  ………. What is the core of the earth made up of? What is the innermost layer of the earth? What are the three layers of the earth? What is crust? What is the uppermost layer of the earth called ?

18. RECAP: HAVE FUN ...

19. CHAPTER-2 INSIDE OUR EARTH CLASS -2 LEARNING OBJECTIVE FOR THIS CLASS ROCKS TYPES OF ROCKS DATE: .07.2020

20. ROCKS AND MINERALS The earth’s crust is made up of various types of rocks. Any natural mass of mineral matter that makes up the earth’s crust is called a rock. Rocks can be of different colour , size and texture.

21. TYPES OF ROCKS There are 3 major types of rocks- IGNEOUS ROCKS 1. 2. 3 . SEDIMENTARY ROCKS METAMORPHIC ROCKS

22. WORD ORIGIN IGNEOUS: Latin word Ignis meaning fire . SEDIMENTARY: Latin word sedimentum meaning settle down. METAMORPHIC: Greek word metamorphose meaning change of form.

23. IGNEOUS ROCKS Igneous: Latin word Ignis meaning fire. When the molten magma cools, it becomes solid. Rocks thus formed are called igneous rocks. They are also called primary rocks.

24. TYPES OF IGNEOUS ROCKS

25. Extrusive Igneous Rocks

26. Intrusive Igneous Rocks GRANITE IS AN EXAMPLE OF INTRUSIVE IGNEOUS ROCK

27. SEDIMENTS AND SEDIMENTARY ROCKS

28. IMPORTANT FACT SEDIMENTARY ROCK TURNED INTO A METAMORPHIC ROCK

29. The hard rocks are used for making roads, houses and buildings. Stones are used in many games. For example, seven stones ( pitthoo ), hopscotch ( stapu /kit kit), five stones ( gitti ). Rocks are used in making monuments. Eg. - Red fort, Taj mahal, etc. USES OF ROCKS The Red Fort is made OF RED SANDSTONE The Taj Mahal is made of white marble

30. Quiz time Rocks are made up of minerals. True or False The rock which is made up of molten magma is------- Name three types of rocks. What are the uses of rocks?

31. RECAP: HAVE FUN ...

32. CHAPTER-2 INSIDE OUR EARTH CLASS -3 LEARNING OBJECTIVE FOR THIS CLASS Rock cycle Minerals DATE: .07.2020

33. ROCK CYCLE DEFINITION- This process of transformation of the rock from one to another runder certain conditions in a cyclic manner is known as the ROCK CYCLE.

34. PROCESS OF ROCK CYCLE When the molten magma cools; it solidifies to become igneous rock. These igneous rocks are broken down into small particles that are transported and deposited to form sedimentary rocks. When the igneous and sedimentary rocks are subjected to heat and pressure they change into metamorphic rocks. The metamorphic rocks which are still under great heat and pressure melt down to form molten magma. This molten magma again can cool down and solidify into igneous rocks

35. RECAP: HAVE FUN ...

36. MINERALS AND THERE USES : Rocks are made up of different Minerals. Minerals are naturally occurring substances which have certain physical properties and definite chemical composition. Minerals are very important to humankind. Some are used as fuels. For example, coal, natural gas and petroleum. They are also used in industries – iron, aluminum, gold, uranium, etc., in medicine, in fertilizers, etc .

37. FOR FUN ( i ) What are the minerals most commonly used in the following objects? (ii) Identify some more objects made up of different minerals Objects Minerals most commonly used in them Karhai Ornaments Lamp Hammer Bell Pan/Tava

38. Quiz time

39. Quiz time 1. List the minerals that are used as fuels? 2. Not all rocks complete the entire rock cycle. a. True False 3. ------------ is made up of one or more minerals. a. mineral b. sandstone c. shale d. rock