block diagram of a monoclineThe Grandview-Phantom Monocline in the Grand Canyon, ArizonaMonocline at Colorado National MonumentMonocline formed at tip of small thrust fault, Brims Ness, Caithness, Scotland
Amonocline (or, rarely, a monoform) is a step-like fold in rock strata consisting of a zone of steeper dip within an otherwise horizontal or gently dipping sequence.
Monoclines may be formed in several different ways (see diagram)
By differential compaction over an underlying structure, particularly a large fault at the edge of a basin due to the greater compactibility of the basin fill, the amplitude of the fold will die out gradually upwards.[1]
By mild reactivation of an earlier extensional fault during a phase of inversion causing folding in the overlying sequence.[2]
As a form of fault propagation fold during upward propagation of an extensional fault in basement into an overlying cover sequence.[3]
As a form of fault propagation fold during upward propagation of a reverse fault in basement into an overlying cover sequence.[4]
^"61. Beaumaris Cliffs 3 - Monocline". Sites of Geological and Geomorphological Significance. Agriculture Victoria. 8 June 2017. Retrieved 1 March 2018.
^Nowell, D.A.G. (1997). "Structures affecting the coast around Lulworth Cove, Dorset and syn-sedimentary Wealden faulting". Proceedings of the Geologists' Association. 108 (4): 257–268. Bibcode:1997PrGA..108..257N. doi:10.1016/S0016-7878(97)80011-9.
^Kluska, B.; Rospondek, M.J.; Marynowski, L.; Schaeffer, P. (2013). "The Werra cyclotheme (Upper Permian, Fore-Sudetic Monocline, Poland): Insights into fluctuations of the sedimentary environment from organic geochemical studies". Applied Geochemistry. 29: 73–91. Bibcode:2013ApGC...29...73K. doi:10.1016/j.apgeochem.2012.09.010.
