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Which of the following statements are correct with reference to the sand dunes?
Barchans are parabolic dunes with the points or wings directed towards the wind direction.
  • Seifs are one-winged barchans which form when there is a shift in wind conditions.
  • Longitudinal dunes form when the supply of sand is poor and wind direction is constant.
    Select the correct answer using the code given below.
    • a)
      1 and 2 only
    • b)
      2 and 3 only
    • c)
      1 and 3 only
    • d)
      1,2 and 3
    Correct answer is option 'B'. Can you explain this answer?
    Verified Answer
    Which of the following statements are correct with reference to the s...
    Dry hot deserts are good places for sand dune formation. Obstacles to initiate dune formation are equally important. There can be a great variety of dune forms.o Crescent-shaped dunes called barchans with the points or wings directed away from wind direction i.e., downwind, form where the wind direction is constant and moderate and where the original surface over which sand is moving is almost uniform. Hence, statement 1 is not correct, o Parabolic dunes form when sandy surfaces are partially covered with vegetation. That means parabolic dunes are reversed barchans with wind direction being the same, o Seif is similar to barchan with a small difference. Seif has only one wing or point. This happens when there is shift in wind conditions. The lone wings of seifs can grow very long and high. Hence, statement 2 is correct.
    o Longitudinal dunes form when the supply of sand is poor and wind direction is constant. They appear as long ridges of considerable length but low in height. Hence, statement 3 is correct, o Transverse dunes are aligned perpendicular to the wind direction. These dunes form when the wind direction is constant and the source of sand is an elongated feature at right angles to the wind direction. They may be very long and low in height.
    o When sand is plenty, quite often, the regular shaped dunes coalesce and lose their individual characteristics.
    o Most of the dunes in the deserts shift and a few of them will get stabilised especially near human habitations.
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    Most Upvoted Answer
    Which of the following statements are correct with reference to the s...
    Explanation:

    Barchans:
    - Barchans are crescent-shaped sand dunes with the points or wings directed towards the wind direction.
    - They are commonly found in areas with moderate sand supply and a constant wind direction.
    - The wind blows sand particles up the gently sloping windward side of the dune and deposits them on the steeper lee side, forming the characteristic crescent shape.

    Seifs:
    - Seifs are one-winged barchans that form when there is a shift in wind conditions.
    - In areas where the wind direction changes frequently, the barchans may lose one wing and transform into seifs.
    - Seifs are elongated dunes with a single curved crest and a steep windward face.

    Longitudinal Dunes:
    - Longitudinal dunes form when the supply of sand is poor and the wind direction is constant.
    - They are parallel ridges of sand that form perpendicular to the wind direction.
    - These dunes are typically long, straight, and have a low height compared to other types of dunes.

    Correct Statements:
    - Statement 2 is correct: Seifs are one-winged barchans that form when there is a shift in wind conditions.
    - Statement 3 is correct: Longitudinal dunes form when the supply of sand is poor and the wind direction is constant.

    Incorrect Statements:
    - Statement 1 is incorrect: Barchans have the points or wings directed towards the wind direction, not away from it. The windward side of a barchan is gentle, while the leeward side is steeper.

    Therefore, the correct answer is option B) 2 and 3 only.
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    Which of the following statements are correct with reference to the sand dunes? Barchans are parabolic dunes with the points or wings directed towards the wind direction. Seifs are one-winged barchans which form when there is a shift in wind conditions. Longitudinal dunes form when the supply of sand is poor and wind direction is constant. Select the correct answer using the code given below.a)1 and 2 onlyb)2 and 3 onlyc)1 and 3 onlyd)1,2 and 3Correct answer is option 'B'. Can you explain this answer?
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    Which of the following statements are correct with reference to the sand dunes? Barchans are parabolic dunes with the points or wings directed towards the wind direction. Seifs are one-winged barchans which form when there is a shift in wind conditions. Longitudinal dunes form when the supply of sand is poor and wind direction is constant. Select the correct answer using the code given below.a)1 and 2 onlyb)2 and 3 onlyc)1 and 3 onlyd)1,2 and 3Correct answer is option 'B'. Can you explain this answer? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Which of the following statements are correct with reference to the sand dunes? Barchans are parabolic dunes with the points or wings directed towards the wind direction. Seifs are one-winged barchans which form when there is a shift in wind conditions. Longitudinal dunes form when the supply of sand is poor and wind direction is constant. Select the correct answer using the code given below.a)1 and 2 onlyb)2 and 3 onlyc)1 and 3 onlyd)1,2 and 3Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Which of the following statements are correct with reference to the sand dunes? Barchans are parabolic dunes with the points or wings directed towards the wind direction. Seifs are one-winged barchans which form when there is a shift in wind conditions. Longitudinal dunes form when the supply of sand is poor and wind direction is constant. Select the correct answer using the code given below.a)1 and 2 onlyb)2 and 3 onlyc)1 and 3 onlyd)1,2 and 3Correct answer is option 'B'. Can you explain this answer?.
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