Pieghe meccanismi di piegamento interferenza Meccanismi di piegamento

Pieghe (meccanismi di piegamento, interferenza)

Meccanismi di piegamento Buckling Bending

Bending

Buckling

Piegamenti sovrapposti In many areas, particularly within the internal parts of mountain belts, folds can be developed more than once. Consequently outcrops and regions can show patterns that indicate fold interference, generated by a later set of folds refolding another.

+ = Type 1 refolding. The fold form on the right represents the overprinting, or second fold.

+ = Type 2 refolding. The fold form on the right represents the overprinting, or second fold.

+ = Type 3 refolding. The fold form on the right represents the overprinting, or second fold.

A "type 1" fold interference pattern, characterised by domes and basins. Looking down on the outcrop surface, this pattern derives from two upright fold sets, one trending L-R across the screen and the other up and down. Classic outcrop from Loch Monar, Scotland.

A "type 2" fold interference pattern which generates rather strange "winged" or "butterfly" outcrop patterns. Looking down on the outcrop, this pattern results from a recumbent first phase of folding (with hinges trending up and down the screen) followed by upright folds trending L-R. Loch Monar, Scotland. A "type 3" fold interference pattern which generates tongue-shapes. These shapes original from near-recumbent axial surfaces being refolded by upright folds, but with hinge lines nearly parallel.