Question

How many types of folds are there?
A. 2
B. 4
C. 3
D. 7

Answer 1

Hint: Different types of folds form on different types of rocks. How dense a folded form depends on the type of rock and the force of compression. For the same pressure, a dense fold could be formed for the sedimentary rock and a lesser dense fold could be formed for igneous rock.

Complete step-by-step answerThe folds are formed as the Earth’s crust experiences compression. These two forces converge and form the folds. A fold consists of three basic types, which are anticline, syncline, and monocline. The upper part of the fold is called an anticline and the lower part is known as a syncline. The line joining these both i.e., the anticline and the syncline is called limb. The vertical plane which cuts the fold is known as the axial plane and the point where the axial plane coincides with the anticline at the top of the limb is considered as the axis of the fold or fold axis. A monocline is a simple bend in the rock so that it no longer remains horizontal. If the angle between the axial plane and the limb on both sides is similar, then it is known as a Symmetric fold. If it is not similar, then it is known as the Asymmetric fold. When both the limbs are symmetric and parallel to each other, then it is known as the Isoclinal fold. If the limbs of the Isoclinal fold are nearly horizontal, then it is known as the Recumbent fold. An overturned fold is such a type in which both the limbs dip in the same direction.

Thus, option (C) is correct.

Note: There are only three basic types of folds which are considered i.e., anticline, syncline, and monocline. Symmetric folds, Asymmetric folds, Isoclinal folds, and Recumbent folds are other types of folds in which anticline, syncline, and monocline could be divided into each of them.