Abstract - Normal faults have irregular geometries on a range of scales arising from different processes including refraction
and segmentation. A fault with constant dip and displacement on a large-scale will have irregular geometries
on smaller scales, the presence of which will generate fault-related folds and down-fault variations in throw. A quantitative
model is presented which illustrates the deformation arising from movement on irregular fault surfaces, with fault-bend
folding generating geometries reminiscent of normal and reverse drag. Calculations based on the model highlight how fault throws are partitioned between continuous
(i.e. folding) and discontinuous (i.e. discrete offset) strain along fault bends for the full range of possible fault dip changes. These calculations illustrate
the potential significance of strain partitioning on measured fault throw and the potential errors that will arise if account is not taken of the
continuous strains accommodated by folding and bed rotations. We show that fault throw can be subject to errors of up to ca. 50% for realistic down-dip fault
bend geometries (up to ca. 40), on otherwise sub-planar faults with constant displacement. This effect will provide irregular variations in
throw and bed geometries that must be accounted for in associated kinematic interpretations.
Solid Earth, 11, 935-945, doi: https://doi.org/10.5194/se-11-935-2020, 2020.