Question

Buckle folds result from

• A. layer parallel shortening
• B. layer perpendicular slip
• C. layer parallel shearing
• D. layer perpendicular shortening

Answer 1

The Correct Option is A

Buckle folds are a structural feature commonly studied in geology. They are formed when layers of rock undergo compressive stress. Let's explore the correct answer and the reasoning behind it:

Concept Explanation

• Buckle Folding: This is a type of geological fold resulting from the deformation of rock layers due to compressive forces. Buckle folds typically occur due to shortening within the plane of the layers.

Analysis of Options

1. Layer Parallel Shortening: This is the process by which rock layers are compressed and pushed closer together, parallel to their original orientation. This type of stress is the primary cause of buckle folds, as it leads to the layers bending or buckling to accommodate the strain.
2. Layer Perpendicular Slip: This involves displacement or movement occurring perpendicular to the layers, which would not typically result in buckle folds but rather faulting or other types of deformation.
3. Layer Parallel Shearing: This refers to a shear stress applied parallel to the layers, causing layers to slide past each other without necessarily bending or buckling.
4. Layer Perpendicular Shortening: Shortening in this manner could result in different deformation styles, like flattening, but not specifically buckle folding.

Conclusion

Based on the explanation above, the correct answer is layer parallel shortening because buckle folds arise from compressive forces that shorten rock layers along their planes, causing them to buckle to relieve stress. The other options involve different directions or mechanisms of stress that do not result in buckle folds.