GEOLOGY

Detailed explanation-1: -When rocks deform in a ductile manner, instead of fracturing to form faults or joints, they may bend or fold, and the resulting structures are called folds. Folds result from compressional stresses or shear stresses acting over considerable time.

Detailed explanation-2: -Ductile deformation indicates shape change of a material through bending or flowing during which chemical bonds may become broken but subsequently reformed into new bonds.

Detailed explanation-3: -Figure 10.9: Folds are a result of ductile deformation of rocks in response to external forces.

Detailed explanation-4: -In Shear folding, small fractures cleave and the rocks in the layers are displaced along the fractures to produce the fold. This is a brittle deformation mechanism. At high enough temperatures, the rocks will flow, producing folds by ductile deformation.

Detailed explanation-5: -Ductile deformation occurs when enough stress is applied to a material that the changes in its shape are permanent, and the material is no longer able to revert to its original shape. For example, if you bend a metal bar too far, it can be permanently bent out of shape.