KINK-BANDS, EXTENSIONAL OR NORMAL
The difference between the normal and reverse kink bands is shown in
figure accompanying this text. If the compressive stress acts parallel to
the layering, conjugate kink-bands or box folds are produced but if it
acts at an angle to the layering, a single set of kink-bands are developed
more or less at the exclusion of the other. Patterson and Weiss (1966)
produced conjugate and single kink-bands experimentally and one of their
significant conclusions has been that under large shortening, kink-bands
are converted into chevron folds. Dewey (1966) made significant
contribution towards our understanding of the nature and origin of
kink-bards and Arvid Johnson and his coworkers have presented through a
series of papers (see 1976 numbers of Tectonophysics) the origin of
kink-bands by extensive theoretical treatment of the problem of their
origin and geometry.
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