# GIS-Based Rockfall Susceptibility Zoning in Greece

## Abstract

**:**

## 1. Introduction

## 2. Rockfall Inventory

## 3. Evaluation of the Rockfall Inventory

#### 3.1. Geological Framework and Rockfalls in Greece

^{3}with an exception of Eptachori rockslide. The blocks size is less than 1 m

^{3}in 22 sites and between 1 and 5 m

^{3}in eight sites, as presented in Figure 2b.

#### 3.1.1. Temporal–Spatial Frequency of Rockfalls

^{3}the return period is 2.8 years, while for events with volume greater than 10 m

^{3}, the return period is 16 years. The frequency of rockfalls is shown in Figure 3. It is noted that the number of rockfalls has increased in the 2000–2010 and 2010–2020 decades, which may be attributed to reasons related with climate change (more extreme weather events) or increase of knowledge of rockfall outbreaks through improvement of communication systems.

#### 3.1.2. Triggering Mechanisms

#### 3.1.3. Coseismic Rockfalls in Greece

_{w}) of the earthquake, and the distance of the rockfall site from the earthquake epicenter are reported.

_{w}= 5.7 and 6.7, while the maximum distance from the epicenter to a reported rockfall was 36.8 km.

#### 3.1.4. Impact of Rockfalls in Greece

_{w}6.4 earthquake in Lefkada in 2015, resulting in one casualty (Saroglou et al., 2018 [30]).

## 4. Rockfall Susceptibility

#### 4.1. Introduction

#### 4.2. Susceptibility Factors

#### 4.2.1. Slope Gradient

#### 4.2.2. Lithology

#### 4.2.3. Rainfall Intensity

#### 4.2.4. Earthquake Intensity

#### 4.2.5. Presence of Faults

#### 4.3. Susceptibility Map

## 5. Discussion

## 6. Conclusions

_{w}= 5.7 and 6.7, while the distance from the epicenter to a reported rockfall was between 3 and 37 km.

## Acknowledgments

## Conflicts of Interest

## References

- Mason, P.J.; Rosenbaum, M.S. Geohazard mapping for predicting landslides: An example from the Langhe Hills in Piemonte, NW Italy. Q. J. Eng. Geol. Hydrogeol.
**2002**, 35, 317–326. [Google Scholar] [CrossRef] - Mancini, F.; Ce-ppi, C.; Ritrovato, G. GIS and statistical analysis for landslide susceptibility mapping in the Daunia area, Italy. Nat. Hazard Earth Syst. Sci.
**2010**, 10, 1851–1864. [Google Scholar] [CrossRef] [Green Version] - Calvello, M.; Cascini, L.; Mastroianni, S. Landslide zoning over large areas from a sample inventory by means of scale-dependent terrain units. Geomorphology
**2013**, 182, 33–48. [Google Scholar] [CrossRef] - Carrara, A.; Cardinalli, M.; Detti, R.; Guzzetti, F.; Pasqui, V.; Reichenbach, P. GIS Techniques and statistical models in evaluating landslide hazards. Earth Surf. Process Landf.
**1991**, 16, 427–445. [Google Scholar] [CrossRef] - Barredo, J.J.; Benavides, A.; Hervas, J.; Van Western, C.J. Comparing heurisitc landslide hazard assessment techniques using GIS in the Trijana basin, Gran Canaria Island, Spain. Int. J. Appl. Earth Obs. Geoinf.
**2000**, 2, 9–23. [Google Scholar] [CrossRef] - Fernandez, T.; Irigaray, C.; Hamdouni, R.E.; Chacon, J. Methodology for landslide susceptibility mapping by means of a GIS, application to the Contraviesa Area (Granada, Spain). Nat. Hazards
**2003**, 30, 297–308. [Google Scholar] [CrossRef] - Kolat, C.; Doyuran, V.; Ayday, C.; Suzen, M.L. Preparation of a geotechnical microzonation model using GIS Systems based on Multicriteria decision Analysis. Eng. Geol.
**2006**, 87, 241–255. [Google Scholar] [CrossRef] - Yilmaz, I.; Yildirim, M. Structural and geomorphological aspects of the Kat landslides (Tokat-Turkey) and susceptibility mapping by means of GIS. Environ. Geol.
**2006**, 50, 461–472. [Google Scholar] [CrossRef] - Nandi, A.; Shakoor, A. A GIS-based landslide susceptibility evaluation using bivariate and multivariate statistical analyses. Eng. Geol.
**2009**, 110, 11–20. [Google Scholar] [CrossRef] - Paulin, G.L.; Bursik, M.; Hubp, J.L.; Mejia, L.M.P.; Quesada, F.A. A GIS method for landslide inventory and susceptibility mapping in the Rio El Estado watershed, Pico de Orizaba volcano, Mexico. Nat. Hazards
**2014**, 71, 229–241. [Google Scholar] [CrossRef] - Brabb, E.E. Innovative approaches to landslide hazard mapping. In Proceedings of the 4th International Symposium on Landslides, Toronto, ON, Canada, 16–21 September 1984; Volume 1, pp. 307–324. [Google Scholar]
- Guzzetti, F.; Reichenbach, P.; Ardizzone, F.; Cardinali, M.; Galli, M. Estimating the quality of landslide susceptibility models. Geomorphology
**2006**, 81, 166–184. [Google Scholar] [CrossRef] - Ferrari, F.; Giacomini, A.; Thoeni, K. Qualitative rockfall hazard assessment: A comprehensive review of current practices. Rock Mech. Rock Eng.
**2016**, 49, 2865–2922. [Google Scholar] [CrossRef] - Fell, R.; Corominas, J.; Bonnard, C.; Cascini, L.; Leroi, E.; Savage, W.Z. Guidelines for landslide susceptibility, hazard and risk-zoning for land use planning. Eng. Geol.
**2008**, 102, 85–98. [Google Scholar] [CrossRef] - Chau, K.T.; Wong, R.H.C.; Liu, J.; Lee, C.F. Rockfall hazard analysis for Hong Kong based on rockfall inventory. Rock Mech. Rock Eng.
**2003**, 36, 383–408. [Google Scholar] [CrossRef] - Chau, K.T.; Tang, Y.F.; Wong, R.H.C. GIS based rockfall hazard map for Hong Kong. Int. J. Rock Mech. Min. Sci.
**2004**, 41, 846–851. [Google Scholar] [CrossRef] - Čarman, M.; Kumelj, S.; Komac, M.; Ribicic, M. Rockfall susceptibility map of Slovenia. In Proceedings of the Interdisciplinary Rockfall Workshop, Innsbruck, Austria, 16–19 May 2011. [Google Scholar]
- Trigila, A.; Frattini, P.; Casagli, N.; Catani, F.; Crosta, G.; Esposito, C.; Iadanza, C.; Lagomarsino, D.; Mugnozza, G.S.; Segoni, S.; et al. Landslide susceptibility mapping at national scale: The Italian case study. In Landslide Science and Practice; Springer: Berlin/Heidelberg, Germany, 2013; pp. 287–295. [Google Scholar]
- Günther, A.; Reichenbach, P.; Malet, J.P.; Van Den Eeckhaut, M.; Hervás, J.; Dashwood, C.; Guzzetti, F. Tier-based approaches for landslide susceptibility assessment in Europe. Landslides
**2013**, 10, 529–546. [Google Scholar] [CrossRef] - Koukis, G.; Sabatakakis, N.; Nikolaou, N.; Loupasakis, C. Landslide Hazard Zonation in Greece; Sassa, K., Fukuoka, H., Wang, F., Wang, C., Eds.; Springer: Berlin/Heidelberg, Germany, 2005; pp. 291–296. [Google Scholar]
- Sabatakakis, N.; Koukis, G.; Vassiliades, E.; Lainas, S. Landslide susceptibility zonation in Greece. Nat. Hazards
**2013**, 65, 523–543. [Google Scholar] [CrossRef] - Antoniou, A.A.; Lekkas, E. Rockfall susceptibility map for Athinios port, Santorini island, Greece. Geomorphology
**2010**, 118, 152–166. [Google Scholar] [CrossRef] - Papazachos, B.C.; Papazachou, C. The Earthquakes of Greece; Editions ZITI: Thessaloniki, Greece, 1997; 304p. [Google Scholar]
- Pavlides, S.; Caputo, R. Tectonophysics Magnitude versus fault’s surface parameters: Quantitative relationships from the Aegean Region. Tectonophysics
**2004**, 380, 159–188. [Google Scholar] [CrossRef] - Ambraseys, N.N.; Jackson, J.A. Seismicity and associated strain of central Greece between 1890 and 1988. Geophys. J. Int.
**1990**, 101, 663–708. [Google Scholar] [CrossRef] [Green Version] - Saroglou, H. Rockfall hazard in Greece. Bull. Geol. Soc. Greece
**2013**, 47, 1429–1438. [Google Scholar] [CrossRef] - Papathanassiou, G.; Valkaniotis, S.; Ganas, A.; Pavlides, S. GIS-based statistical analysis of the spatial distribution of earthquake–induced landslides in the island of Lefkada, Ionian Islands, Greece. Landslides
**2013**, 10, 771–783. [Google Scholar] [CrossRef] - Zygouri, V.; Koukouvelas, I.K. Evolution of rock falls in the Northern part of the Peloponnese, Greece. IOP Conf. Ser. Earth Environ.
**2015**, 26, 012043. [Google Scholar] [CrossRef] [Green Version] - Saroglou, H.; Asteriou, P.; Tsiambaos, G.; Manousakis, J.; Zekkos, D. Study of co-seismic rockfalls during Lefkada and Cephallonia Earthquakes, Greece. In Proceedings of the 3rd North American Symposium on Landslides, Roanoke, VA, USA, 4–8 June 2017; pp. 521–528. [Google Scholar]
- Saroglou, H.; Asteriou, P.; Zekkos, D.; Tsiambaos, G.; Clark, M.; Manousakis, J. UAV-based mapping, back analysis and trajectory modeling of a coseismic rockfall. Nat. Hazards Earth Syst. Sci.
**2018**, 18, 321–333. [Google Scholar] [CrossRef] - Koukis, G.; Ziourkas, C. Slope instability phenomena in Greece: A statistical analysis. Bull. Int. Assoc. Eng. Geol.
**1991**, 43, 47–60. [Google Scholar] [CrossRef] - Sartori, M.; Baillifard, F.; Jaboyedoff, M.; Rouiller, J.-D. Kinematics of the 1991 Randa rockslides (Valais, Switzerland). Nat. Hazards Earth Syst. Sci.
**2003**, 3, 423–433. [Google Scholar] [CrossRef] [Green Version] - Marquínez, J.; Menéndezduarte, R.; Farias, P.; Jiménez Sánchez, M. Predictive GIS-based model of rockfall activity in mountain Cliffs. Nat. Hazards
**2003**, 30, 341–360. [Google Scholar] [CrossRef] - Dorren, L.; Seijmonsbergen, A. Comparison of three GIS-based models for predicting rockfall runout zones at a regional scale. Geomorphology
**2003**, 56, 49–64. [Google Scholar] [CrossRef] - Nikolaou, N.; Pogiatzi, E.; Spanos, N. Report on Landslides in Greece on 2010; I.G.M.E. (Instituto Geologico y Minero de Espana): Madrid, Spain, 2011; p. 8. [Google Scholar]
- Gorum, T.; Fan, X.; van Westen, C.J.; Huang, R.Q.; Xu, Q.; Tang, C.; Wang, G. Distribution pattern of earthquake-induced landslides triggered by the 12 May 2008 Wenchuan earthquake. Geomorphology
**2011**, 133, 152–167. [Google Scholar] [CrossRef] - Wasowski, J.; Del Gaudio, V. Evaluating seismically induced mass movement hazard in Caramanico Terme (Italy). Eng. Geol.
**2000**, 58, 291–311. [Google Scholar] [CrossRef] - Rodriguez-Peces, M.J.; Garcia-Mayordomo, J.; Azanon, J.; Jabaloy, A. Regional Hazard Assessment of Earthquake-Triggered Slope Instabilities considering Site Effects and Seismic Scenarios in Lorca Basin (Spain). Environ. Eng. Geosci.
**2011**, 17, 183–196. [Google Scholar] [CrossRef] - Marzorati, S.; Luzi, L.; De Amicis, M. Rock falls induced by earthquakes: A statistical approach. Soil Dyn. Earthq. Eng.
**2002**, 22, 565–577. [Google Scholar] [CrossRef] - Keefer, D.K. Landslides caused by earthquakes. Bull. Geol. Soc. Am.
**1984**, 95, 406–421. [Google Scholar] [CrossRef] - Rodriguez, C.E.; Bommer, J.J.; Chandler, R.J. Earthquake induced landslides: 1980–1997. Soil Dyn. Earthq. Eng.
**1999**, 18, 325–346. [Google Scholar] [CrossRef] - Papadopoulos, G.A.; Plessa, A. Magnitude–distance relations for earthquake–induced landslides in Greece. Eng. Geol.
**2000**, 58, 377–386. [Google Scholar] [CrossRef] - Chousianitis, K.; Del Gaudio, V.; Sabatakakis, N.; Kavoura, K.; Drakatos, G.; Bathrellos, G.D.; Skilodimou, H.D. Assessment of Earthquake-Induced Landslide Hazard in Greece: From Arias Intensity to Spatial Distribution of Slope Resistance Demand. Bull. Seismol. Soc. Am.
**2016**, 106, 174–188. [Google Scholar] [CrossRef] - Marinos, P.; Kavvadas, M.; Tsiambaos, G.; Saroglou, H. Rock slope stabilization in Mythimna castle, Lesvos island, Greece. In Proceedings of the 1st European Conference on Landslides, Prague, Czech Republic, 24–26 June 2002; pp. 635–639. [Google Scholar]
- Koukouvelas, I.; Litoseliti, A.; Nikolakopoulos, K.; Zygouri, V. Earthquake triggered rock falls and their role in the development of a rock slope: The case of Skolis Mountain, Greece. Eng. Geol.
**2015**, 191, 71–85. [Google Scholar] [CrossRef] - Saroglou, H.; Berger, F.; Bourrier, F.; Asteriou, P.; Tsiambaos, G.; Tsagkas, D. Effect of forest presence on rockfall trajectory. An example from Greece. In Proceedings of the 12th International Congress of IAEG, Torino, Italy, 13–19 September 2015. [Google Scholar]
- Christaras, B.; Vouvalidis, K. Rockfalls in the archaeological site of Delphi, Greece. In Proceedings of the IAEG 2010 International Congress, Auckland, New Zealand, 5–10 September 2010. [Google Scholar]
- Marinos, P.; Tsiambaos, G. Earthquake triggering rock falls affecting historic monuments and a traditional settlement in Skyros Island, Greece. In Proceedings of the International Symposium: Landslide Risk Mitigation and Protection of Cultural and Natural Heritage, Kyoto, Japan, 21–25 January 2002; pp. 343–346. [Google Scholar]
- Saroglou, H.; Marinos, V.; Marinos, P.; Tsiambaos, G. Rockfall hazard and risk assessment: An example from a high promontory at the historical site of Monemvasia, Greece. Nat. Hazards Earth Syst. Sci.
**2012**, 12, 1823–1836. [Google Scholar] [CrossRef] - Gupta, R.P.; Saha, A.K.; Arora, M.K.; Kumar, A. Landslide Hazard Zonation in part of the Bhagirathi Valley, Garhwal Mimalyas, using integrated remote sensing—GIS. Himal. Geol.
**1999**, 20, 71–85. [Google Scholar] - Meisina, C.; Piccio, A.; Tocchio, A. Some aspects of the landslide susceptibility in the Sorba Valley (western Alps, Italy). In Proceedings of the International Conference on Landslides—Causes, Impacts and Countermeasures, Davos, Switzerland, 17–21 June 2001; Kuhne, M., Einstein, H.H., Krauter, E., Klapperich, H., Pottler, R., Eds.; VGE: Essen, Germany, 2001; pp. 547–556. [Google Scholar]
- Baillifard, F.; Jaboyedoff, M.; Sartori, M. Rockfall hazard mapping along a mountainous road in Switzerland using a GIS-based parameter rating approach. Nat. Hazards Earth Syst. Sci.
**2003**, 3, 431–438. [Google Scholar] [CrossRef] - Coe, J.A.; Harp, E.L. Influence of tectonic folding on rockfall susceptibility, American Fork Canyon, Utah, USA. Nat. Hazards Earth Syst. Sci.
**2007**, 7, 1–14. [Google Scholar] [CrossRef] [Green Version] - Fityus, S.G.; Giacomini, A.; Buzzi, O. The significance of geology for the morphology of potentially unstable rocks. Eng. Geol.
**2013**, 162, 43–52. [Google Scholar] [CrossRef] - Krautblatter, M.; Moser, M. A nonlinear model coupling rockfall and rainfall intensity based on a four year measurement in a high Alpine rock wall (Reintal, German Alps). Nat. Hazards Earth Syst. Sci.
**2009**, 9, 1425–1432. [Google Scholar] [CrossRef] - Harp, E.L.; Jibson, R.W. Anomalous concentrations of seismically triggered rock falls in Pacoima Canyon: Are they caused by highly susceptible slopes or local amplification of seismic shaking. Bull. Seismol. Soc. Am.
**2002**, 92, 180–189. [Google Scholar] [CrossRef] - EPPO. Greek Seismic Code; Earthquake Planning and Protection Organization: Athens, Greece, 2003. [Google Scholar]
- Kim, Y.-S.; Peacock, D.C.; Sanderson, D.J. Fault damage zones. J. Struct. Geol.
**2004**, 26, 503–517. [Google Scholar] [CrossRef] - Shipton, Z.K.; Cowie, P.A. A conceptual model for the origin of fault damage zone structures in high-porosity sandstone. J. Struct. Geol.
**2003**, 25, 333–344. [Google Scholar] [CrossRef] - Brideau, M.A.; Stead, D.; Kinakin, D.; Fecova, K. Influence of tectonic structures on the Hope Slide, British Columbia, Canada. Eng. Geol.
**2005**, 80, 242–259. [Google Scholar] [CrossRef] - Rondoyanni, T.; Lykoudi, E.; Triantafyllou, A.; Papadimitriou, M.; Foteinos, I. Active faults affecting linear engineering projects: Examples from Greece. Geotech. Geol. Eng.
**2013**, 31, 1151–1170. [Google Scholar] [CrossRef]

**Figure 5.**Impact of main rockfall events: (

**a**) on local road network in Lefkada during 2003 earthquake (site 3) (

**b**) on National Highway in Tempi valley in 2009 (site 11), (

**c**) in Alyki village in 2019 (site 43), (

**d**) in Monemvasia archaeological site (site 19).

Id | Location | Type | Date | Trigger | Rock Type | Fault Scarp | Block (m^{3}) | Impact |
---|---|---|---|---|---|---|---|---|

1 | Santomeri, Achaia | D | 8/6/2008 | E (6.5) | L | Y | 4 | DH |

2 | Leonidio, Tiros | R | 6/1/2008 | E | L | Y | <1 | RC |

3 | Drimonas, Lefkada | D/R | 14/8/2003 | E (6.4) | L | Y | <1 | DR |

4 | Lefkada, Ag.Nikitas | D/R | 14/8/2003 19/11/2015 | E (6.4) Ε (6.5) | L | Y | 13.7 2 | PDR HLL |

5 | Skyros Island | A | 26/7/2001 | E (5.8) | L | Y | 1–2 | DC |

6 | Ladas, Eleochori, Poliani, Kalamata | D | 13/9/1986 | E (6.2) | L | <1 | PDH | |

7 | Heraklion (Pitsidia, Akoumia) | D | 14/5/1959 | E (6.3) | L | Y | <1 | DH |

8 | Geraneia Mt. | 24/2/1981 | E (6.3) | L | Y | |||

9 | Itea, Monastiraki | R | 18/1/2010 | E (5.1) | L | Y | <1 | DR |

10 | Konitsa, Ioaninna | D/A | 8/1998 | E | LA | 2 | DH | |

11 | Tempi Valley | R | 17/12/2009 2004,1977 ^{1} | ND | M | 0.5–5, 50 | HLL, RC | |

12 | Kourtaliotis gorge | R | 4/3/2012 | R | L | Y | 1 | DR |

13 | Pramanta -Ioannina | R | 9/3/2004 | ND | L | Y | <1 | DR |

14 | Acronafplia | A | 1/2010 | ND | L | 0.5 | V | |

15 | Tithorea, Parnassos | D | 19/12/2010 1999, 1957 | ND | L | 10 | DH | |

16 | Oksilithos, Kymi | R | 13/8/2008 | ND | MS | 1.5 | HI | |

17 | Eptachori, Kastoria | D | 1935, 51, 68, 70,87, 93, 94 | R | M | Y | 336 ^{2} | DH |

18 | Delfi ancient site | A | 2003, 09 ^{1} | R | L | 8 | V | |

19 | Monemvasia | A | 2003, 2010 ^{1} | R | L | Y | 2 | DH, V |

20 | Anc. Olympia | R | 22/1/2013 | R | L | 0.5 | DR | |

21 | Klokova Mt. | R | 16/11/2012 | ND | L | 1–2 | DR | |

22 | Therma Ikaria | D | 10/1978 | ND | M | Y | 1 | PDH |

23 | Ag. Fotia, Crete | R | - | ND | S | <1 | DR | |

24 | Taxiarches, Lesvos | D | 1963, 3/11/09 | ND | M | Y | 1 | DH |

25 | Mythimna, Lesvos | A | 2001 | R | A | 0.3 | ND | |

26 | Kakia Scala | R | 20/11/2000 | R | L | Y | 0.5 | HLL |

27 | Argos Castle | A | 1987 | ND | L | D | ||

28 | Kefalari, Argos | D | 20/4/2012 | ND | L | Y | 0.1 | HLL |

29 | Stypsi, Lesvos | D | 1963, 1977 | R | A | 0.5-3.0 | DH | |

30 | Orliagas, Ziakas | D/R | ND | L | Y | 1 | ND | |

31 | Carpathos, Akropoli | D | - | ND | L | - | ||

32 | Vageni Distomo | D/R | ND | C | Y | 40 | PDR | |

33 | Kalymnos | D | 12/2002 | R | L | 4 | PDH | |

34 | Molaoi, Lakonia | D | 2/2003 | R | CA | 1–2 | PDH | |

35 | Chora, Ios | D | - | ND | S | 1 | PDH | |

36 | Vouliagmeni, Attica | D | 1/1982 | ND | L | Y | 1–2 | |

37 | Kamena Vourla | D | 27/8/2012 | ND | L | 1 | DH | |

38 | Nea Pefki, Trikala | R | 20/10/2010 | R | S | <1 | DR | |

39 | Topolia, Chania | R | 23/2/2012 | R | L | Y | 0.5 | FB |

40 | Santorini | D | 2011 | R | P | 0.5 | HLL | |

41 | Myrtos, Cephallonia Island | O | 17/1/2014 | E (6.1) | L | Y | 50 | DR |

42 | Lesvos, Plomari | D | 24/11/2018 | R | SG | 10 | DH | |

43 | Alyki, Voiotia | D | 27/1/2019 | R | L | 70 | DH |

^{1}More rockfall events exist, which are not presented here,

^{2}the largest rock block, 15 smaller rocks have fallen in this site, Type: R = Roadway, D = Domestic, A: Archeological, O = other (touristic area, coast), Trigger: R = rainfall, E = Earthquake, ND = Not defined, Rock type: L = limestone, M = marble, CA = Calcitic agglomerate, LA = Limestone agglomerate, C = conglomerates, S = sandstone, M = marls, MS = marls/sandstones, SG = Schist/gneiss, A = Andesite, P = Pyroclastics, Fault Scarp: Y = yes, Impact: HLL = Human loss, HI = Human injury, V = Potential impact on visitors, damage to archaeological site, DH = Damage to houses, PDH = Potential house damage, RC = Roadway closure, DR=Damage on roadway, PDR = Potential roadway damage, FB = fall on moving bus, DC = Damage on cars, ND = No damage.

No. | Location | Date | Magnitude (Mw) | Rockfall Site | Distance (km) |
---|---|---|---|---|---|

1 | Gerania, Korinthos | 13/9/1986 | 6.7 | Alkyonides | 27 |

2 | Kalamata | 8/1998 | 6 | Kalamata-Sparti road | 6.5 |

3 | Konitsa | 14/8/2003 | 5.7 | Eptachori | 36.8 |

4 | Skyros | 24/2/1981 | 6.5 | Skyros castle | 20.5 |

5 | Lefkada | 26/7/2001 | 6.3 | Ag. Nikitas | 7 |

6 | Achaia | 8/6/2008 | 6.4 | Santomeri | 5.9 |

7 | Cephallonia | 26/01/2014 | 5.9 | Myrtos | 16.4 |

8 | Lefkada | 11/2015 | 6.4 | Ag. Petros | 2.8 |

Geological Formation | Rockfall Susceptibility | Class |
---|---|---|

Postalpine (Marls, claystones, etc.) | Low | 3 |

Gypsum | Low | 3 |

Schists | Low | 3 |

Molasse deposits | Moderate | 2 |

Flysch | Moderate | 2 |

Igneous rocks (granites etc.) | Moderate | 2 |

Marble–Schist (alternations) | Moderate | 2 |

Dolomites | High | 1 |

Limestone | High | 1 |

Volcanic sedimentary rocks | High | 1 |

Gneiss–Marbles | High | 1 |

Rainfall Intensity (Height of Rainfall per Year) | Rockfall Susceptibility | Class |
---|---|---|

<600 mm | Low | 3 |

600 mm < R < 1200 mm | Moderate | 2 |

>1200 mm | High | 1 |

Earthquake Intensity | Rockfall Susceptibility | Class |
---|---|---|

<0.12 g | Low | 3 |

0.12 g < a < 0.24 g | Moderate | 2 |

>0.24 g | High | 1 |

**Table 6.**Rating matrix for the calculation of Rockfall Susceptibility Index (RSI). Category of low susceptibility in grey, moderate in green, and high in red.

RSI | Earthquake (class 1) | Earthquake (class 2) | Earthquake (class 3) |
---|---|---|---|

Lithology + Rainfall classes (sum = 2) | 3 | 4 | 5 |

Lithology + Rainfall classes (sum = 3) | 4 | 5 | 6 |

Lithology + Rainfall classes (sum = 4) | 5 | 6 | 7 |

Lithology + Rainfall classes (sum = 5) | 6 | 7 | 8 |

Lithology + Rainfall classes (sum = 6) | 7 | 8 | 9 |

© 2019 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Saroglou, C.
GIS-Based Rockfall Susceptibility Zoning in Greece. *Geosciences* **2019**, *9*, 163.
https://doi.org/10.3390/geosciences9040163

**AMA Style**

Saroglou C.
GIS-Based Rockfall Susceptibility Zoning in Greece. *Geosciences*. 2019; 9(4):163.
https://doi.org/10.3390/geosciences9040163

**Chicago/Turabian Style**

Saroglou, Charalampos.
2019. "GIS-Based Rockfall Susceptibility Zoning in Greece" *Geosciences* 9, no. 4: 163.
https://doi.org/10.3390/geosciences9040163