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(left) The seismic section above shows a narrowing upward fold limb, or growth triangle, where bed dips within the fold limb generally do not shallow upward, consistent with folding by kink-band migration. Dipmeter data in the wells corroborates the reflector dips. (upper right) In this section, a fanning and upward shallowing of limb dips within growth strata are consistent with folding by progressive limb rotation. The core of the anticline is filled with salt, which presumably thickened during deformation, leading to progressive rotation of the overlying fold limbs. (lower right) The growth structure in this section contains both a growth triangle and a fanning of limb dips, suggesting folding by a combination of kink-band migration and limb rotation mechanisms. Kinematic theories that employ hybrid folding mechanisms include shear fault-bend folds (Suppe et al., 2004; see section 1A-4 of AAPG Studies in Geology #53: Seismic Interpretation of Contractional Fault-Related Folds, An AAPG Seismic Atlas, edited by John H. Shaw, Christopher D. Connors and John Suppe, 2005.), certain classes of detachment folds (Dahlstrom, 1990; Hardy and Poblet, 1994; see section 1B-3 of AAPG Studies in Geology #53: Seismic Interpretation of Contractional Fault-Related Folds, An AAPG Seismic Atlas, edited by John H. Shaw, Christopher D. Connors and John Suppe, 2005.), and trishear fault-propagation folds (Erslev, 1991; Hardy and Ford, 1997; Allmendinger, 1998; see section 1B-2 of AAPG Studies in Geology #53: Seismic Interpretation of Contractional Fault-Related Folds, An AAPG Seismic Atlas, edited by John H. Shaw, Christopher D. Connors and John Suppe, 2005.). From AAPG Studies in Geology #53: Seismic Interpretation of Contractional Fault-Related Folds, An AAPG Seismic Atlas, edited by John H. Shaw, Christopher D. Connors and John Suppe, 2005. Pages 1-59.