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Folds. By: Michelle Castaneda 1 st Period Geology. What is a fold?. Folds are flat lying sedimentary and volcanic rocks, often bent into a series of wavelike undulations. Most folds are the result of compressional stresses that result in the shortening and thickening of the crust.
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Folds By: Michelle Castaneda 1st Period Geology
What is a fold? Folds are flat lying sedimentary and volcanic rocks, often bent into a series of wavelike undulations. Most folds are the result of compressional stresses that result in the shortening and thickening of the crust. Limbs are the two sides of the fold. Hinge is the line drawn along the points of maximum curvature of each layer. The hinge is often inclined at an angle known as the plunge. Axial plane is an imaginary surface that divides a fold as symmetrical as possible
Folds are described as: • Some folds plunge because the axis of the fold penetrates into the ground.
Ridges and valleys result because of differential weathering and erosion. In the real world folds are generally intimately coupled with faults. Example of this close association are broad, regional features called monoclines. Monoclines are large, steplike folds in otherwise horizontal sedimentary strata.