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The regional-scale salients and recesses in the Appalachian orogen are well accepted as being a product of tectonic inheritance. Smaller map-view curves are present in the slate belt of the Taconic allochthon, which lies between the New York recess and Quebec salient, and we investigate the possibility that these curves are also related to the geometry of the preexisting Iapetan rift margin. The orientation of the slaty cleavage (S2) and mineral/stretching lineation (L2) and the geometry of syntectonic fibers were used to identify along-strike differences in the nature of the main stage of deformation (D2) in the slate belt. Where the axial traces of F2 folds lie parallel to the overall trend of the Taconic allochthon, the strata are characterized by an approximately downdip L2, plane strain, monoclinic strain symmetry, and top-to-west-northwest noncoaxial flow. The strata also underwent noncoaxial flow where the axial traces of F2 folds are oblique to the overall trend of the Taconic allochthon. However, L2 rakes moderately from the south on S2, and syntectonic fibers record evidence for flattening strain, triclinic strain symmetry, top-to-northwest shear in the XZ plane, and sinistral shear in the XY plane. We infer that the deformation zone in which D2 structures formed changed orientation along strike such that the region of obliquely oriented F2 folds underwent transpression, and we suggest that the transpressional deformation was a result of reactivation of a northwest-striking Iapetan transform fault as an oblique ramp during the Taconic orogeny.

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