geology 3120 - describing folds
DESCRIPTION
Geology 3120 - Describing Folds. Outline. Terms For Describing Folds Parasitic Folds Vergence. Initial Layer Cake. Direction of Closing. inflection point. inflection point - change in curvature (i.e., concave to convex). Convexity and Age of Beds. - PowerPoint PPT PresentationTRANSCRIPT
Direction of ClosingDirection of Closing
inflection point - change in curvature (i.e., concave to convex)
inflection point
Convexity and Age of Beds Convexity and Age of Beds
• Anticline - a fold that is convex in the direction of youngest bedsAnticline - a fold that is convex in the direction of youngest beds
• Syncline - a fold that is convex in the direction of oldest bedsSyncline - a fold that is convex in the direction of oldest beds
Interlimb AngleInterlimb Angle
Five Categories:Five Categories:
Gentle Gentle
OpenOpen
CloseClose
TightTight
IsoclinalIsoclinal
Cylindrical or Non-Cylindrical Cylindrical or Non-Cylindrical
FoldsFolds
non-cylindrical foldnon-cylindrical fold
Parasitic FoldsParasitic Folds
Parasitic foldsParasitic folds
always vergealways verge
towards anticlinestowards anticlines
and away from and away from
synclinessynclines
Parasitic FoldsParasitic Folds
Parasitic folds verge towards anticlines and away from synclinesParasitic folds verge towards anticlines and away from synclines
Parasitic folds verge towards anticlines and away from synclinesParasitic folds verge towards anticlines and away from synclines
ReferencesReferences
Most figures from:Most figures from:
http://earth.leeds.ac.uk/folds/describing/folddesc.htm