Abstract -
Extensive opencast lignite mining in the Ptolemais Basin, NW Greece has exposed a plethora of outcrops within a
normal fault system offsetting a sequence of interbedded lignites and marls of Pliocene age. The entire length of a
630 m long fault over a vertical interval of 80 m has been mapped in detail from 48 mine faces. The mapped fault
comprises 5 fault segments large enough to be mapped in 3D, smaller fault segments exposed on individual mine
faces and associated continuous deformation in the form of bed rotations and normal drag. These fault components
combined to provide a regular aggregate throw distribution over the mapped fault. The boundaries
between adjacent fault segments have a variety of geometries and they may be fully unconnected or they may
link along strike or down dip within the fault zone. The fault geometry and throw distribution is analysed using
two approaches, a discrete mapping of the large fault segments and a continuous approach based on measures of
fault thickness and throw partitioning at individual outcrops. This combination of approaches demonstrates that
fault thickness and the proportion of fault throw on the individual fault segments observed on any cross-section
through the fault are related almost entirely to fault segmentation in 3D.
Journal of Structural Geology, 136, 104009. doi: https://doi.org/10.1016/j.jsg.2020.104009