Reconstruction of linear folding structures with the use of volume balancing

The structure of linear fold zones is considered as a set of objects of several hierarchic levels with specific kinematic models of their formation. The prefolded structure was reconstructed, and recent depths of the sedimentary cover base were predicted on the basis of these notions with the use of the Northwestern Caucasus folding as an example. Fold domains were used as the main objects. The basic parameters of their geometry (dips of axial surfaces, dips of fold system levels, shortening values) measured in natural structures were identified with the deformation ellipsoid. Three kinematic operations: rotation, simple horizontal shearing, and extension, which made it possible to reconstruct the horizontal layering and the position of the profile line segment for each domain. Eleven profiles were reconstructed by the consecutive joining of the prefolded states of the domains. The fold shortenings were obtained for these profiles and their 42 parts. The developed quasi-three-dimensional model of the natural structure demonstrates specific features important for the verification of geodynamic models.