Scaling properties of normal fault populations in the western Corinth Graben, Greece: implications for fault growth in large strain settings

A variety of one-dimensional and two-dimensional map techniques of fractal analysis have been employed to investigate the scaling properties of the dominant WNW-trending normal fault population of the western Corinth graben in central Greece. To assess possible constraints on fault geometry during fault growth, the data have been compiled separately from the northern and southern domains of the graben, which have experienced differing amounts of finite strain. Based on power-law distributions of the fault throw, the applied extension is estimated at 30% and 22% for the northern and southern domains, respectively. However, the fault spacing and fault length populations in both domains obey similar power-law relationships. These conclusions are also supported by maximum throw vs. trace-length data, which demonstrate that the faults in the northern domain have systematically higher values for the slip-to-length ratios than those in the southern domain. It is proposed that the Corinth graben has reached ‘fracture saturation’ that is, the fault spacing stops evolving and displacement increases rather than faults lengthening to accommodate the increasing extension. This growth process, consistent with throw distributions along individual faults, may be explained either in terms of a stress feedback mechanism, or by the mechanical interaction between the WNW-trending normal faults with a set of NNE-trending transverse faults.