A buckled, bent, or contorted rock. Folds result from complex processes including fracture, sliding, shearing, and flowage. Delcaillau et al. (2006) Geomorph. 76, 3–4 report on recent fold growth in India. An arch-like upfold is an anticline, a downfold is a syncline. A complex anticline is an anticlinorium (see J. Conley1973 on the Blue Ridge anticlinorium) and a complex syncline is a synclinorium (see Röhlich (2007) Bull. Geosci. 82, 2 on the Prague synclinorium). In an overturned fold the upper limb of the syncline and the lower limb of the anticline dip in the same direction. In recumbent folds the beds in the lower limb of the anticline and the upper limb of the syncline are upside down. G. Bennison and K. Moseley (2003) have excellent block diagrams of various fold types.
Subjects: Earth Sciences and Geography.