DOI: 10.5281/zenodo.16728922
title: NOAFAULTS  KMZ layer Version 7.0

description: The NOAFAULTs database of active faults of Greece was first published in 2013 at BGSG (versions 1.0 & 1.1; http://dx.doi.org/10.12681/bgsg.11079). Version 2.1 (see map below) was published in 2018 http://doi.org/10.5281/zenodo.3483136); Version 3.0 was published in 2020 http://doi.org/10.5281/zenodo.4304613; Version 4.0 was published in 2022 https://zenodo.org/record/6326260 ; Version 5.0 was published in 2023 https://doi.org/10.5281/zenodo.8075517 ; Version 6.0 was published in 2024 https://zenodo.org/records/13168947 . NOAFAULTs was created towards compiling a digital database of fault traces, geometry and additional attributes (kinematics, slip rate, associated seismicity etc.) primarily to support seismicity monitoring at the National Observatory of Athens (NOA). It has been constructed from published fault maps in peer-reviewed journals since 1972 while the number of the scientific papers that have contributed with fault data in version 7.0 is 158. The standard commercial software ARCGIS has been used to design and populate the database. The fault layer was produced at NOA by on-screen digitization of fault traces at the original map-scale (as drawn by the reference paper it was taken from) and is available through our web portal application https://arcg.is/04Haer supported by ESRI.

In this version, in order to streamline the process, avoid inconsistencies during data input, and ensure a homogeneous database, we decided to automatically calculate certain fields from the attribute table. Specifically, the Strike and Dip-Direction fields were derived programmatically. First, the digitization of the faults was carried out to align with the dip-direction of each. With this method of digitization, the user also could apply a symbol to each fault that correctly corresponds to its dip-direction, enhancing the accuracy and interpretability of the fault representation. Then, by calculating the line bearing of the fault and applying a ±180° function to the result, the Strike was determined. Subsequently, using the calculated strike and appropriate functions, the Dip-Direction of each fault was generated. If the dip angle was not provided by the scientific source, we assigned standard values: 60° for Normal faults, 30° for Reverse faults, and 90° for Strike-Slip faults. Consequently, the Rake field was assigned values of -90° for Normal, 90° for Reverse, and 0° or 180° for Strike-Slip faults, depending on relative sense of motion.

Four new thematic layers were added to V7.0: the Sampling Sites layer, which includes locations from paleoseismological trenches and 36CL sampling sites; the NOA Surface Rupture Database layer, which contains documented surface ruptures from field mapping ; and the Cyprus Faults layer, provided by the Cyprus Geological Survey Department (GSD[1]) , incorporated after initial evaluation and selection of specific features. Furthermore, the Focal Mechanisms layer from the NOA Gisola Catalogue (2012–2025) was updated to include data up to 3 June 2025, while the Strong Earthquakes in Greece since 1964 layer was updated with events up to 2 June 2025. In addition, one more station was added to the RING GNSS Network (INGV) layer, enhancing the coverage and detail of the database Moreover, the Rupture Plane of the 2020 Samos Earthquake (M7.0) was added.



In this version a total number of 3441 active faults are included. 91.8% of the active faults are normal faults, 5.4% are strike-slip faults and only 2.8% represent the reverse faults. 390 new fault traces were added in South Gulf of Evia, NW Crete, Karpathos Island, North Peloponnese, Amorgos basin (fault codes range from GR3436 to GR3825). Also, reliable data on slip rates is available for 164 faults. Limited data on instrumental and historical seismicity are linked to 173 and 121 active faults, respectively. In addition, a) surface-rupturing geological data and b) data on the proximity of epicentres of strong seismic events to the traces of active faults allows the identification of 109 rupturing faults (seismic faults) that included in this version of the database. The NOAFAULTs database shows that nearly 51% of its active faults imply high seismic risk level in the broader area of Greece. These active faults can generate surface faulting or strong ground motions that can cause serious damage to buildings and infrastructures and therefore represent a significant hazard, particularly in the densely populated and industrialized areas of Greece.




[1] https://www.moa.gov.cy/moa/gsd/gsd.nsf/All/870AEC05A4324A31C22585F9003EC70B?OpenDocument



 

Since 2022 NOAFAULTs has contributed to the EFSM20 database (https://www.seismofaults.eu/efsm20).
description: The following contributors are gratefully acknowledged: Ms Varvara Tsironi PhD, Mr Georgios Goutsos BSc, Mr Nikolaos Madonis BSc, Ms Eirini Efstathiou MSc, Ms Christina Tsimi MSc, Mr Sotiris Valkaniotis PhD, Ms Elisavet Kollia MSc, Ms Nikoletta Andritsou BSc, Mr George Evangelou BSc, Mr Michael Delagas MSc, Ms Athanassia Oikonomou BSc, Ms Fotini Kounavi MSc, Ms Vasiliki Kanavou BSc, Ms Emmanuella Konstantakopoulou MSc, Mr Vassilios Georgakopoulos BSc, and Mr Panagiotis Savvaidis BSc.