THE Mw 6.8 OCTOBER 26, 2018 ZAKYNTHOS (IONIAN SEA, GREECE) EARTHQUAKE

Issue No.10 November 2018 THE Mw 6.8 OCTOBER 26, 2018 ZAKYNTHOS (IONIAN SEA, GREECE) EARTHQUAKE Dr. Efthymis Lekkas Professor of Dynamic, Tectonic & Applied Geology & Natural Disaster Management President of the Earthquake Planning and Protection Organization Director of the Post Graduate Program Environmental, Disaster, and Crises Management Strategies PhD c. Spyridon Mavroulis Geologist MSc Prevention & Management of Natural Disasters

Issue No. 10, November 2018 2 About Non-periodic publication of the Post-graduate Studies Program Environmental Disasters & Crises Management Strategies" of the National & Kapodistrian University of Athens, issued after significant events for the immediate information of the scientific community and the general public. The publication includes also scientific data from various research teams from universities, organizations and research institutes. Publishers: Dr. Efthymis Lekkas Dr. Nikolaos Voulgaris Dr. Stylianos Lozios Technical Editing: PhD c. Spyridon Mavroulis Communication: PhD c. Spyridon Mavroulis (smavroulis@geol.uoa.gr) MSc Alexia Grambas (agram@geol.uoa.gr) MSc Katerina-Nafsika Katsetsiadou (knavsika@geol.uoa.gr) Copyrights All copyrights of scientific data belong to their respective owners, while the copyrights of this publication belong to the publishers. Cited as Lekkas, E., Mavroulis, S. (2018). The Mw 6.8 October 26, 2018 Zakynthos (Ionian Sea, Greece) Earthquake. Newsletter of Environmental, Disaster and Crisis Management Strategies, 10. Scientific Mission Of the National and Kapodistrian University of Athens, Faculty of Geology and Geoenvironment, Department of Dynamic Tectonic Applied Geology Contributors Dr. Efthymis Lekkas, PhD c. Spyridon Mavroulis The scientific team visited the earthquake affected area shortly after the earthquake in order to conduct a geological reconnaissance of the affected area which is mainly affected by the earthquake and to assess the effects on the natural environment and buildings. This study was funded by the Environmental, Disaster and Crises Management Strategies Post graduate Program of the Department of Geology and Geoenvironment of the National and Kapodistrian University of Athens. https://edcm.edu.gr

Issue No. 10, November 2018 3 MAIN TECTONIC ELEMENTS IN THE EASTERN MEDITERRANEAN REGION THE HELLENIC ARC AND TRENCH SYSTEM From Papanikolaou et al. (2004), the TRANSMED Atlas

MAIN TECTONIC ELEMENTS IN THE EASTERN MEDITERRANEAN REGION THE HELLENIC ARC AND TRENCH SYSTEM Issue No. 10, November 2018 4

THE HELLENIC ARC AND TRENCH SYSTEM Issue No. 10, November 2018 5

Issue No. 10, November 2018 6 GEOTECTONIC MAP OF GREECE GEOTECTONIC UNITS AND TECTONOSTRATIGRAPHIC TERRANES From Papanikolaou (2015), Geology of Greece

Issue No. 10, November 2018 7 OFFSHORE ZAKYNTHOS BASIN IN EASTERN ZAKYNTHOS OFFSHORE AREA Outline structural map of continental shelf around Cephalonia and Zakynthos Islands Seismic section SW-NE across offshore Zakynthos Basin, northern part of Hydra Bank and offshore Cephalonia Basin and Simple structural interpretations of seismic sections from Zakynthos and Cephalonia Channels From Brooks and Ferentinos (1984), Journal of the Geological Society, London

Issue No. 10, November 2018 8 OFFSHORE ZAKYNTHOS BASIN IN EASTERN ZAKYNTHOS OFFSHORE AREA Outline structural map of continental shelf around Cephalonia and Zakynthos Islands Seismic section WNW-ESE across offshore Zakynthos Basin, northern part of Hydra Bank and offshore Cephalonia Basin and Simple structural interpretations of seismic sections from Zakynthos and Cephalonia Channels From Brooks and Ferentinos (1984), Journal of the Geological Society, London

Issue No. 10, November 2018 9 OFFSHORE ZAKYNTHOS BASIN IN EASTERN ZAKYNTHOS OFFSHORE AREA Outline structural map of continental shelf around Cephalonia and Zakynthos Islands Seismic section across deeper part of Zakynthos basin between Zante harbour and Killini From Brooks and Ferentinos (1984), Journal of the Geological Society, London

Issue No. 10, November 2018 10 OFFSHORE ZAKYNTHOS CHANNEL AND BASIN (a) Single channel, air-gun, geophysical record across the Zakinthos and Kephalonia Basins (location and line interpretation shown in b and c, respectively), highlighting the development of peripheral sinks and synsedimentary unconformitites adjacent to the diapirs (D). Section and scale after Brooks and Ferentinos (1984). From Underhill (1988), Journal of the Geological Society, London

Issue No. 10, November 2018 11 ACTIVE SUBMARINE VALLEY/CANYON SYSTEM: ZAKYNTHOS VALLEY/CANYON Detailed bathymetry (in m) of the Zakynthos valley/canyon system, based upon survey data and U.S. Navy Hydrographic Chart No. NAR-8, 3407 and U.K. Admiralty Charts. Arrows show longitudinal axis of the valley/canyon system and its tributaries. From Ferentinos et al. (1985), Marine Geology

Issue No. 10, November 2018 12 SEISMIC PROFILES AND SETTING OF SOUTHERN ZAKYNTHOS OFFSHORE AREA From Kokkalas et al. (2013) Tectonophysics The interpreted seismic profile Z-141 through the Ionian (Ion) and Pre-Apulian (P-A) zones in Zakynthos offshore area showing the different lithoseismic sequences, the structural features and the details of data acquisition and processing sequence of the seismic line. IT: Ionian Thrust, ZSF: Zakynthos-Strofades Fault, ZSB: Zakynthos-Strophades Basin.

Issue No. 10, November 2018 13 SEISMIC PROFILES AND SETTING OF SOUTHERN ZAKYNTHOS OFFSHORE AREA From Kokkalas et al. (2013) Tectonophysics The interpreted seismic profile Z-141 through the Ionian (Ion) and Pre-Apulian (P-A) zones in Zakynthos offshore area showing the different lithoseismic sequences, the structural features and the details of data acquisition and processing sequence of the seismic line. IT: Ionian Thrust, ZSF: Zakynthos-Strofades Fault, ZSB: Zakynthos-Strophades Basin.

Issue No. 10, November 2018 14 GENERAL MORPHOLOGY OF THE PELOPONNESE CONTINENTAL MARGIN General morphology of the Peloponnese continental margin from Zakynthos to the northern Matapan trough and the Mediterranean Ridge inner basins (From Wardell et al. 2014, Bollettino di Geofisica Teorica ed Applicata)

Issue No. 10, November 2018 15 TOPOGRAPHY-BATHYMETRY OF THE SOUTHWESTERN HELLENIC ARC Morphology from the Island of Zakynthos to the area of Pylos), based on swath bathymetric data collected by the R/V Explora (DTM at 50 m). Note the very narrow continental shelf, the wide plateau-like middle slope (bypassed by several active channels related to canyons and gullies), the westward bordering Strophades deep basin, the Zakynthos - Strophades massive Ridge and the deep bordering continental slope. In insert, track lines of the R/V Explora swath survey in 2007. From Camera et al. (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 16 TOPOGRAPHY-BATHYMETRY OF THE SOUTHWESTERN HELLENIC ARC A - The upper slope west of Cape Katakolo showing many small canyons, gullies and sedimentary scars. B - The area just west of Kyparissiakos Gulf, with a very narrow shelf, many gullies and slope-bypassing channels; its northern shelf area is subjected to syn-sedimentary faulting leading to important destabilizations and submarine slides. C - The acoustic basement ridge just south of the Zakynthos Island which appears shaped by many probable fault scarps. D - The massive acoustic basement rise from which the small Strophades Islands are emerging. In insert, locations of the four illustrated areas on a general morphologic map. From Camera et al. (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 17 BATHYMETRIC AND STRUCTURAL MAP OF THE PELOPONNESE CONTINENTAL MARGIN Simplified bathymetry showing the seismic lines used in Wardell et al. (2014) Bollettino di Geofisica Teorica ed Applicata Structural sketch map of the Peloponnese continental margin From Wardell et al. 2014, Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 18 VP VELOCITY MODELS FOR THE PELOPONNESE CONTINENTAL MARGIN (Right) Vp velocity model of Line P1_2006 with tectonic interpretation. LaFZ: Lapithas fault zone, KFZ: Kyparissia fault zone, FI-FZ: Filiatra fault zone. (Middle) Final velocity model of Line P1-2007 south of Zakynthos. Crust thickens to the ENE to approximate 20 km below the Alpine units. Alpine nappes glide over the pre-apulia limestone over the Triassic evaporites. (Left) Final velocity model along the Line P2-2007, south of P1-2007, between the islands of Zakynthos and Strophades. Triassic evaporites separate the Alpine from the pre-apulia limestones and sediments. From Makris and Papoulia (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 19 SEISMICITY OF THE SOUTHWESTERN HELLENIC ARC Depth distribution of recorded seismicity along profiles AB and CD. Moho depth is constrained by active seismic observations. Potential active faults from various sources (Mariolakos et al., 1985; IGME, 1989; Papanikolaou et al., 2007) are drawn along the profiles. From Papoulia et al. (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 20 TOPOGRAPHY-BATHYMETR AND OFFSHORE TECTONIC STRUCTURES 3D presentation of the topography-bathymetry (top), basement geometry (middle) and crustal thickness (bottom) in the south western Hellenic Arc From Papoulia et al. (2014), Bollettino di Geofisica Teorica ed Applicata Simplified tectonic map offshore western Peloponnese derived from active seismic observations From Makris and Papoulia (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 21 SUBSURFACE AND STRATIGRAPHY OF WESTERN GREECE AND OFFSHORE NORTHERN ZAKYNTHOS ION-7 General interpretation of seismic line ION-7 between 0km and 178.7km Seismic line ION-7, 86.3km to 131.3km: Part north of Zakynthos Island Seismic line ION-7 From Kokinou et al. (2006), Marine Geophysical Researches) ION-7

Issue No. 10, November 2018 22 SUBSURFACE AND STRATIGRAPHY OF WESTERN GREECE AND THE IONIAN SEA Block diagrams of Western Greece and the Ionian Sea based on digitized contours of surface and subsurface relief. The W-E cross-section corresponds to seismic line ION-7, and illustrates the subsurface structures and stratigraphy. From Kokinou et al. (2005), Journal of Petroleum Geology

Issue No. 10, November 2018 23 GEOLOGICAL MAP OF ZAKYNTHOS ISLAND From Lekkas (1993)

Issue No. 10, November 2018 24 GEOTECTONIC UNITS AND TECTONIC STRUCTURE OF ZAKYNTHOS ISLAND From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 25 TECTONIC STRUCTURE OF ZAKYNTHOS ISLAND Faults in Zakynthos Island Classification of faults based on their throw From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 26 DRAINAGE SYSTEM AND INCISION ZONES IN ZAKYNTHOS ISLAND Drainage system Incision zones From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 27 MORPHOLOGICAL DISCONTINUITIES AND PLANATION SURFACES IN ZAKYNTHOS ISLAND Morphological discontinuities Planation surfaces due to deposition and erosion From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 28 ACTIVE FAULTS IN ZAKYNTHOS ISLAND AND PERIOD OF ACTIVATION From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 29 MAIN ACTIVE FAULT ZONES AND NEOTECTONIC FAULT BLOCKS IN ZAKYNTHOS ISLAND From Lekkas (1993), Neotectonic Map of Zakynthos Island

Issue No. 10, November 2018 30 NEOTECTONIC MAP OF ZAKYNTHOS ISLAND From Lekkas (1993)

Issue No. 10, November 2018 31

Issue No. 10, November 2018 32 GEOLOGY OF ZAKYNTHOS ISLAND From Institute of Geology and Mineral Explorations (1983)

Issue No. 10, November 2018 33 IONIAN GEOTECTONIC UNIT Lithostratigraphic column of Ionian geotectonic unit From Karakitsios and Rigakis (2007), Journal of Petroleum Geology Triassic to Quaternary stratigraphic column for the Ionian unit From Kokinou et al., 2005, Journal of Petroleum Geology

Issue No. 10, November 2018 34 PAXOI GEOTECTONIC UNIT Lithostratigraphic column of Paxoi geotectonic unit From Karakitsios and Rigakis (2007), Journal of Petroleum Geology

Issue No. 10, November 2018 35 AREAS PRONE TO NATURAL DISASTERS IN ZAKYNTHOS ISLAND Lekkas (1994) Lekkas (1993) Areas prone to tsunamis, landslides and rockfalls, liquefaction phenomena, soil flows and forest fires From Lekkas (1993), Neotectonic Map of Zakynthos Island Lekkas (1994), Bulletin of the Geological Society of Greece

Issue No. 10, November 2018 36 FAULT BLOCKS IN ZΑKYNTHOS ISLAND From Lekkas (1993), Neotectonic Map of Zakynthos Island

FAULT BLOCKS IN ZΑKYNTHOS ISLAND Issue No. 10, November 2018 37

Issue No. 10, November 2018 38 1893 EARTHQUAKE (Χ) 1893 EARTHQUAKE (IΧ)

Issue No. 10, November 2018 39 SEISMICITY AND SEISMIC SOURCES IN ZAKYNTHOS GREATER AREA 19.90 20.30 20.70 21.10 21.50 21.90 38.80 38.80 A1 38.40 38.40 20.30 20.50 20.70 20.90 21.10 21.30 38.50 38.50 1668 1862 38.00 38.00 38.30 1767 VII 1759 VIII 1867 IX 1658 X 38.30 37.60 L1 37.60 A3 L3 37.20 37.20 A2 L2 36.80 19.90 20.30 20.70 21.10 21.50 36.80 21.90 Depth (km) 0-15 Magnitude M = 7.3 16-30 M = 4.0 > 31 38.10 37.90 37.70 X X 1766 IX 1729 VIII 1752 VIII 1714 VIII 1554 VIII 1636 1742 From Voulgaris (2002) X IX 1592 IX 1791 1840 1893 1664 1873 1820 ΖΑΚΥΝΘΟΣ IX 1696 1509 1633 1622 M = 7.2 IX VIII X IX 1710 1676 1707 M = 6.1 37.50 37.50 20.30 20.50 VIII VII 20.70 VIII 20.90 21.10 21.30 XIX IX VIII 1514 VIII 38.10 37.90 37.70

Issue No. 10, November 2018 40 SEISMICITY AND SEISMIC SOURCES IN ZAKYNTHOS GREATER AREA New seismogenic zonation of Ionian islands, Kyparissiakos gulf and western Peloponnese and major tectonic lineaments associated to seismogenic faultsand earthquakes with Mw 6.0 From SEAHELLARC Working Group (2014), Bollettino di Geofisica Teorica ed Applicata

Issue No. 10, November 2018 41 From Voulgaris (2002) PEAK GROUND-MOTION PARAMETERS FOR ZAKYNTHOS ISLAND 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 37.90 37.80 37.70 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 300 290 280 270 260 250 240 Acceleration (cm/sec/sec) 37.90 37.80 37.70 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 28 26 24 22 20 18 16 Velocity (cm/sec) 37.90 37.80 37.70 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 13 12 11 10 9 8 7 Displacement (cm) 230 14 6 37.60 37.60 220 210 37.60 37.60 12 10 37.60 37.60 5 4 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGA (cm/sec 2 ) map for exceeded probability of 10% in 50 years 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGV (cm/sec) map for exceeded probability of 10% in 50 years 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGD (cm) map for exceeded probability of 10% in 50 years 20.60 20.70 20.80 20.90 21.00 21.10 38.00 38.00 37.90 37.80 37.70 37.60 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 37.60 440 430 420 410 400 390 380 370 360 350 340 330 320 310 300 Acceleration (cm/sec/sec) 37.90 37.80 37.70 37.60 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 37.60 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 Velocity (cm/sec) 37.90 37.80 37.70 37.60 ΖΑΚΥΝΘΟΣ 37.90 37.80 37.70 37.60 16 15 14 13 12 11 10 9 8 7 6 5 Displacement (cm) 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGA (cm/sec 2 ) map for exceeded probability of 10% in 100 years 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGV (cm/sec) map for exceeded probability of 10% in 100 years 37.50 37.50 20.60 20.70 20.80 20.90 21.00 21.10 PGD (cm) map for exceeded probability of 10% in 100 years

Issue No. 10, November 2018 42 HORIZONTAL AND VERTICAL DEFORMATION OF ZAKYNTHOS ISLAND FOR THE PERIOD FROM AUGUST 2005 TO JULY 2006 Large-magnitude earthquakes that occurred offshore to the south in October 2005 and April 2006 most likely contributed to the observed deformation as deduced from DGPS measurements for an encompassing period (August 2005 to July 2006). The largest amount of horizontal deformation occurred in the south, where its western part moved in a W NW direction, while the eastern part moved towards the NE, with magnitudes ranging from 15 to 26 mm. The southern part of the island uplifted a maximum of 65 mm whereas the north subsided from 12 to 28 mm. From Lagios et al. (2007) Tectonophysics

Issue No. 10, November 2018 43 HORIZONTAL AND VERTICAL DISPLACEMENT OF ZAKYNTHOS ISLAND FOR THE PERIOD FROM 2006-2012 Horizontal and Vertical displacement (mm) of the Zakynthos Island GPS network observed for the period (a) 2006-2012 and (b) 2006-2012 (ITRF2008)

Issue No. 10, November 2018 44 SEISMIC ZONES IN IONIAN ISLANDS Zakynthos falls in the third seismic zone of Greece which is characterized by a ground acceleration coefficient of 0.36g corresponding to the greatest seismic strength demand according to the Greek code for Seismic Resistant Structures From Earthquake Planning and Protection Organization (2003) From Mavroulis et al. (2017), 16 th WCEE

Issue No. 10, November 2018 45 HISTORICAL SEISMICITY OF IONIAN ISLANDS Significant historical and instrumentally recorded earthquakes and epicenters that affected the geodynamic evolution of the Ionian Islands From Lekkas et al. (2018), Geotechnical and Geological Engineering

THE OCTOBER 26, 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 46

Issue No. 10, November 2018 47 RECORDED TIME-HISTORIES OF ACCELERATION, VELOCITY AND DISPLACEMENT Zakynthos City Keri http://www.itsak.gr/uploads/news/earthquake_reports/eq_zakynthos_20181026_m6.8.pdf

MOMENT TENSOR SOLUTION OF THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 48

COULOMB STRESS CHANGE AND VETRICAL DISPLACEMENT OF THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 49

GROUND DEFORMATION OF THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 50

Issue No. 10, November 2018 51 COSEISMIC GROUND DEFORMATION OF THE 2018 ZAKYNTHOS EARTHQUAKE Type: co-seismic Master: 2018-10-20 04:39:26 Slave: 2018-10-26 04:40:08 Orbit Number: 80 Mode: DESCENDING

Issue No. 10, November 2018 52 COSEISMIC GROUND DEFORMATION OF THE 2018 ZAKYNTHOS EARTHQUAKE Type: co-seismic Master: 2018-10-20 16:31:29 Slave: 2018-10-26 16:30:56 Orbit Number: 175 Mode: ASCENDING

Issue No. 10, November 2018 53 PRE-SEISMIC AND POST-SEISMIC GROUND DEFORMATION OF THE 2018 ZAKYNTHOS EARTHQUAKE Type: pre-seismic Master: 2018-10-25 16:39:55 Slave: 2018-10-19 16:39:13 Orbit Number: 73 Mode: ASCENDING Type: co-seismic Master: 2018-10-25 16:39:55 Slave: 2018-10-31 16:39:13 Orbit Number: 73 Mode: ASCENDING

INTERFEROGRAM FOR THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 54

SLOPE FAILURES INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 55

Issue No. 10, November 2018 56 SLOPE FAILURES INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE

Issue No. 10, November 2018 57 SLOPE FAILURES INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE

SLOPE FAILURES INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE Issue No. 10, November 2018 58

Issue No. 10, November 2018 59 TSUNAMI INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE https://reliefweb.int/sites/reliefweb.int/files/resources/20181112_greece_tsunami.pdf

Issue No. 10, November 2018 60 VARIATIONS IN SEA LEVEL OBSERVED AT THE SEA OF KATAKOLO (WESTERN PELOPONNESE) INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE http://www.ioc-sealevelmonitoring.org/station.php?code=kata&period=0.5&endtime=2018-10-26t09:00

Issue No. 10, November 2018 61 TSUNAMI INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE Map with earthquake epicenter (red star), arrival times on coasts and alert levels (red, yellow and green colored triangles). Variations in sea level observed at the sea of Le Castella, in the province of Crotone (station managed by INGV, ISPRA and JRC). The long variations due to the tide and those with the highest frequency are noticed in the early hours of October 26 th. https://ingvterremoti.wordpress.com/author/concettanostro/

Issue No. 10, November 2018 62 TSUNAMI INDUCED BY THE 2018 ZAKYNTHOS EARTHQUAKE 0 min 10 min 20 min 30 min 40 min 50 min 60 min 70 min https://ingvterremoti.wordpress.com/author/concettanostro/

Issue No. 10, November 2018 63 Dr. Efthymis Lekkas Professor of Dynamic, Tectonic & Applied Geology & Natural Disaster Management President of the Earthquake Planning and Protection Organization THE Mw 6.8 OCTOBER 26, 2018 ZAKYNTHOS (IONIAN SEA, GREECE) EARTHQUAKE Director of the Post Graduate Program Environmental, Disaster, and Crises Management Strategies PhD c. Spyridon Mavroulis Geologist MSc Prevention & Management of Natural Disasters Zakynthos, 2018