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In the Honalilar area (Denizli Basin, Turkey), the occurrence of banded Ca-carbonate veins and travertine deposits, represented by a dismantled fissure ridge-type depositional system, are the evidence of a middle-late Pleistocene exhumed, shallow, hydrothermal system. Their occurrence offers the best opportunity to: (i) reconstruct the fluid paths from the underground to the palaeo-surface, and (ii) analyse the role of fault zones in controlling the permeability and fluids circulation. Permeability developed in overstepping regional scale normal faults, with a slight left-lateral oblique-slip component. At the surface, faults favored the localization and development of a fissure ridge-type travertine deposit. At depth, the root of the hydrothermal system consists of W-E oriented fractures filled of up to 6.5 m thick Ca-carbonate veins, developed in a high dilatation zone. It corresponds to the step-over determined by the oblique-slip kinematics of the NW-striking main faults. The high dilatation step-over zone contrasted the progressive sealing induced by the concomitant Ca-carbonate deposition within the fractures, thus favoring permeability maintenance and fluids circulation for at least 200 ka. This evidence adds key inputs for predicting permeable volumes during geothermal exploration in areas affected by extensional tectonics. The main NW-oriented faults remained active even after the hydrothermal fluid flow, causing the dismantlement and progressive exhumation of the upper part of the hydrothermal system. © 2020 Elsevier Ltd

The aim of this study is to improve our understanding on the mechanical interaction and linkage process between normal fault segments. Faults grow by the process of radial propagation and the linkage of segments, as strain increases, evolving to large fault systems. For this purpose we conducted a combined field and photogeological study on two major segmented fault zones in Central Greece, the Atalanti and Arkitsa fault zones. This approach includes effects of fault size and spatial distribution, scaling laws and footwall-hanginwall topography. Throw distribution and the geometry of the segmented fault arrays were analyzed in order to investigate the complexity of fault zones, the fault linkage process and the geometric characteristics of the relay zones formed between individual segments. The correlation of fault throw with fault length (D-L) and the ratios of overlap-separation (OL-S), separation-fault segment length (S-L) and relay displacement vs. separation (Dr-S) were examined in order to give an insight for fault segment interaction and linkage .