Question

Folds are the structural features resulting from

• A. ductile deformation of earth crust.
• B. brittle deformation of earth crust.
• C. high impact tectonic stresses of earth crust.
• D. fracturing of earth crust.

Hint:

In geology: ductile = bending (folds), brittle = breaking (faults/fractures).

Answer 1

The Correct Option is A

Folds are wave-like bends formed in rock layers when they undergo slow and continuous compressive forces within the Earth's crust. Under high temperature and pressure conditions found deep below the surface, rocks behave plastically or ductilely, causing them to bend without breaking.
Brittle deformation leads to fractures, joints, or faults, which correspond to options (B) and (D). These processes break rocks instead of bending them. Option (C) refers to strong tectonic stresses, which generally cause fracturing rather than smooth bending.
Therefore, folds are produced specifically by ductile deformation—the plastic bending of rock layers under compressive stress.