1. What is the other name for upright fold?
a) Symmetrical fold
b) Asymmetrical fold
c) Overturned fold
d) Isoclinal fold
Explanation: Symmetrical folds are also called normal folds or upright folds. In such a fold, the axial plane is essentially vertical.
2. Fold in which the limbs lie exactly one over another?
a) Isoclinal
b) Symmetrical
c) Recumbent
d) Asymmetrical
Explanation: In recumbent folds, one limb comes to lie exactly under the other limb so that a drill hole dug at the surface in the upper limb passes through the lower limb also.
3. Which of the following is also an overturned fold?
a) Isoclinal fold
b) Symmetrical fold
c) Asymmetrical fold
d) Recumbent fold
Explanation: Recumbent folds are described as extreme types of overturned folds in which the axial plane acquires an almost horizontal attitude.
4. Fold with flattened top is ___________
a) Square fold
b) Plateau fold
c) Box fold
d) Conjugate fold
Explanation: Box fold may be described as a special type of fold with exceptionally flattened top and steep inclined limbs almost forming three sides of a rectangle.
5. The type of fold in which fold angle is between 10° to 90°?
a) Tight fold
b) Loose fold
c) Gentle fold
d) Acute fold
Explanation: When it comes to fold angle as the basis of classification, the fold with a fold angle between 10° and 90° is called tight fold.
6. Which of the following is not a type of fold based on behaviour with depth?
a) Concentric fold
b) Similar fold
c) Supratenuous fold
d) Asymmetrical fold
Explanation: The first three options are the types based on behaviour with depth where asymmetric fold is based on position of axial plane.
7. Isogans converge inwards in class 1 folds.
a) True
b) False
Explanation: In class 1 folds, isogans converge inwards whereas in class 3, these converge upwards.
8. Where can folds be observed in the southern part of India?
a) Vindhyan region only
b) Satpura region only
c) Vindhyan and Satpura ranges
d) Cannot be observed in southern India
Explanation: Among the peninsular mountains, only the Vindhyan and the Satpuran ranges show folding in a prominent manner.
9. Where is the Liddar Valley Anticline situated?
a) Kashmir Himalayas
b) Uttarakhand Himalayas
c) Sikkim Himalayas
d) Himachal Pradesh Himalayas
Explanation: The Liddar Valley Anticline in Kashmir Himalayas is often represented as a classic example in that almost complete sequence of Palaeozoic Era is fully developed in this anticline.
10. How many types of folds are there with plunge as a basis?
a) 4
b) 3
c) 2
d) 5
Explanation: Only two main types are recognized as the types of folds on the basis plunge.