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Class-VII Sub-Geography Chapter-4(Landforms) (A) Choose the correct option. 1. The differ from the hills terms of: Elevation 2. The ‘Plate tectonic’ is related with the formation of: Fold mountains. 3. Block mountains are formed by: Faulting. 4. Aravalli, Pareshnath, Rajmahal hills are examples of: Residual 5. Rocky, Alps, Himalayas are examples of : Fold mountains 6. Example of a lava is: Columbia plateau. 7. An example of block is: Vosges. 8. Block mountains are formed by : Faulting. 9. Fold mountains are formed by: Movements of plates. 10. In Germany a rift is called: Graben. 11. The usual height of a mountain is: More than 1000 metre. 12. The crust consists of several solid blocks are called: Plates. 13. The elevation of a from the sea level is: less than 200 meter. 14. The plain formed by the depositions of wind borne sand is called: Loess plain. 15. Nilgiri, Ajodhya hills are examples of: Relict mountain. 16. Barren islands of is an example of: Volcanic mountain. 17. The name of the highest volcano in the World is: Mouna Loa in Hawaii. 18. The Chhotanagpur are examples of: Dissected Plateaus. (B) Fill in the blanks. 1. The range is a line of mountain. 2. The Himalayas and the Alps are examples of fold types of mountains. 3. The Pamir Plateau is called the ‘roof of the World’. 4. Lava plateau is formed due to volcanic eruption. 5. One example of intermontane Plateau is Tibetan plateau. 6. Most of the are formed by . 7. The plains areas are most productive for farming. 8. Plains are low level lands. 9. Plains are densely populated. 10. Agriculture is limited in mountain. 11. Tourists go to mountain for scenic beauty. 12. Horst is an uplifted Block mountain. (C) Write true or false. 1. Hills have rounded and mountains have sharp peaks.----True. 2. Aravalli is a young fold mountain.----False. 3. Block mountain has been formed by volcanic eruption.----False. 4. Black Forest of Germany is a graben.---False. 5. Mauna Loa of Hawaii is a fold mountain.-----False. 6. Deccan plateau has been formed by the volcanic eruption. ----True. 7. The valley between two block mountain is called a rift valley.----True. 8. The Mississippi Delta takes the shape of the foot of a bird. -----True. 9. The Nile forms the largest delta in the Worlds.----False. 10. The Malnad plateau are important example of dissected plateau.----False. 11. The Barren islands in the Andaman and Nicobar island of India are examples of volcanic mountaion.----True. 12. In India the Narmada and the Tapti river flew through two rift valley and the Satpuras in between them is a block mountain. ----True. (D) Short types question.(2/3 marks each) 1. What is Peak? Ans) The sharp and pointed top of a mountain is known as a peak. Ex: Mount Everest is the peak of Himalayas. 2. What is range? Ans) When a several mountains stretch over a long distance in a line or chain, they are collectively known as Mountain chain or Range. Ex: The Siwaliks, the Himachal Range. 3. What is a Knot? Ans) A highland from which many mountain ranges radiate or spread out in all directions is called a mountain knot. Example: Pamir Knot. 4. What is horst? Ans) When the land between to parallel fault uplifted then that uplifted land is known as the Horst in German terms. 5. What is Graben? Ans) When two roughly parallel fault occur, the crust between that parallel faults may sink forming narrow steep sided valleys. This is known as Graben in German terms. 6. What is Rift Valley? Ans) When two roughly parallel fault occur the crust between that parallel faults may sink forming narrows steep sided valley which is known as rift valley. Ex: The Great Rift valley(Africa)

The Valley of River Rhine.

The Narmada Valley.

7. Write down the characteristics of the Folded mountains. Ans) The main characteristics of the folded mountain are: a. Fold mountains consist of great masses of folded sedimentary rocks. b. Various types of folds are present in fold mountains. c. Fossils are very common as they originated from sedimentary rocks. d. Most of the peaks conical in shape. 8. What is volcanic mountain? Write down 4 characteristics. Ans) The mountains which are formed in the form of tall conical or domed shaped by the accumulation of lava, as dust and liquid mud on the mouth of the volcano are known as Volcanic Mountains. Ex: Fujiyama, The Barren etc. The characteristic are : a. Most of the volcanic mountains are conical or domed shaped. b. They are formed by the magneous rocks. c. They are steep sided. d. Athe height of the volcanic mountains may vary. 9. What is ? Ans) Inselbergs are outstanding rounded steep sided residual hills. They are mainly formed of granite and gneiss and are remnants of original plateau which has been eroded away by wind action. They have steep slope and rounded top and are found in Kaalahari. 10. What do you mean by Intermontane plateau? Ans) during mountain building movement when fold mountains rise up due to the horizontal pressure on the layers of rocks, the lands in between the mountains also lift up and this lift up land or plateau is known as the Intermontane Plateau. Ex: The Tibetan Plateau. 11. Why Pamir is called the ‘roof of the world’? Ans) The plateaus are of different heights. Some plateaus are very high. Among all the plateaus the height of the Pamir plateau is highest. For this reason Pamir is known as the ‘roof of the World’. 12. What is mountain? Classify different types of mountains. Ans) A mountain is that a landblock whose height is at least 900 meters above the sea level and its slope is very steep. Mountain is classified into four types: a) Folded mountain : Himalayas, Andes. b) Block mountain: Vosges, Satpura. c) Volcanic mountain: Fujiyama, The Barren. d) Residual mountain: The Aravallis. 13. Classify plateaus. And write its importance. Ans) Plateaus are classified into four types: a) Intermontane plateau: Tibetan plateau, Anatolian plateau. b) Volcanic or Lava plateau: Maharastra plateau, The Columbian plateau. c) Dissected plateau d) Continental or Tectonic plateau: The Deccan plateau, The Canadian plateau. Importance of plateau: i. Plateau is a very good sources of minerals like Iron, Copper, Bauxite, Coal etc. ii. The surface of plateau is undulating. As a result those are flown through the plateau region are suitable for navigation and hydro-electricity power generation.

14. What is plains? Write down the importance of plains.

Ans) The Plain is that lowland which has a low relief and eye leveled surface. It’s height is generally 160 meters. The importance of plains are as follows:

i. Plains are flat and fertile areas which are ideally suited for agriculture. ii. Plains are flat areas and provide ideal locations for the construction of railways and roads. iii. Most of world’s urbanization has taken place in the plains. 15. What is Loess plains? Ans) The plain which is formed by the depositional work of wind is known as Loess plain. Ex: West Rajasthan. (E) Write the answer in brief. 1. Describe the formation of folded mountain with suitable sketch. Ans) The mountains which are formed by folding of sedimentary rocks strata of the earth’s crust due to the forces of compression are known as Fold Mountains. Ex: Himalayas. Formation: The formation of Fold Mountain are described depending on the Plate Tectonic Theory…. a) Generally fold mountains are formed due to the forces of compression. When two plates or rigid masses move to each other convergently, then a horizontal pressure originated and acted on the deposited sedimentation. This process is known as Lithogenesis. b) When the pressure exceeds the capacity of tolerance then the sedimentary beds started to bend upward gradually. And the bed created a series of upland and lowand which are known as anticline and syncline. This 2nd stage is known as Orogenesis. c) Finally when the pressure acts very hardly then the bending of the beds very prominent and a series of anticline and syncline are formed which represent itself as a Fold Mountain. This last stage is known as Gliptogenesis.

2. Describe the formation of Block mountain with a suitable sketch. Ans) when a landmass is formed by the upliftment of land between the two parallel faults is known as Block Mountain. Similarly when the land is subsided between the two parallel is known as Rift Valley. Ex: Vosges. Formation: The formation of Block Mountain are described step by step.  Firstly on a plain land two parallel faults are created due to the endogenetic force.  After that when the tension force acts very deeply then middle part between two parallels uplifted and a flat landed mountain is created. That land is normally Block Mountain.  On the other hand, when the middle portion between the fault subsided instead of upliftment , two sided parts are stand like a mountain. In that case the subsided land is known as Rift Valley and two uplifted land are known as Block Mountain.