Rock deformation Folds A fold consist of two limbs which are divided by an imaginary surface called axial plane. The line formed by the intersection of the axial plane and the surface o a rock laver is the fold axis Anticline is a fold with the convex side upward (therefore oldest layers in the middle Syncline is a fold with the concave side upward (therefore youngest layers in the middle) Usually anticlines and synclines alternate in the field. Folds A plunging fold can create interesting map patterns Anticline .Beds are bowed upward . Older beds in core of fold Can be"symmetrical"or asymmetrical4 Rock Deformation Folds A fold consist of two limbs which are divided by an imaginary surface called axial plane. The line formed by the intersection of the axial plane and the surface of a rock layer is the fold axis. Anticline is a fold with the convex side upward (therefore oldest layers in the middle) Syncline is a fold with the concave side upward (therefore youngest layers in the middle) Usually anticlines and synclines alternate in the field. Folds Anticline ïBeds are bowed upward ïOlder beds in core of fold ïCan be ìsymmetricalî or ìasymmetricalî A plunging fold can create ìinterestingî map patterns