1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea) and their relation to tsunamis Y. Altinok, B. Alpar, N. Özer, C. Gazioglu To cite this version: Y. Altinok, B. Alpar, N. Özer, C. Gazioglu. 1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea) and their relation to tsunamis. Natural Hazards and Earth System Sciences, Copernicus Publ. / European Geosciences Union, 2005, 5 (5), pp.717-725. hal-00299270 HAL Id: hal-00299270 https://hal.archives-ouvertes.fr/hal-00299270 Submitted on 23 Sep 2005 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Natural Hazards and Earth System Sciences, 5, 717–725, 2005 SRef-ID: 1684-9981/nhess/2005-5-717 Natural Hazards European Geosciences Union and Earth © 2005 Author(s). This work is licensed System Sciences under a Creative Commons License. 1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea) and their relation to tsunamis Y. Altinok1, B. Alpar2, N. Ozer¨ 1, and C. Gazioglu2 1Istanbul University, Engineering Faculty, Department of Geophysics, 34850 Avcilar, Istanbul, Turkey 2Istanbul University, Institute of Marine Sciences and Management, 34116 Vefa, Istanbul, Turkey Received: 24 March 2005 – Revised: 2 August 2005 – Accepted: 8 September 2005 – Published: 23 September 2005 Part of Special Issue “Tsunami hazard from slope instability” Abstract. The most earthquake-prone areas in the eastern gion is situated at the first-degree hazard zone in the Official central Aegean Sea are the Izmir Bay, the Karaburun penin- Earthquake Hazard Regionalization map of Turkey (1996) sula and the island of Chios. The level of seismic activ- and is currently accelerating its seismic activity. Papazachos ity and tsunami potential are influenced by the presence of et al. (2004) demonstrated the possibility of a very severe normal faults around the region. There have been about 20 event in the near future with magnitudes reaching up to M moderate-size earthquakes from 496 BC to 1949 AD. Among 6.5–6.7. Using a combination of instrumental, historical, and these earthquakes, the ones on the dates 20 March 1389, geodetic data, Koravos et al. (2003) proposed the maximum 13 November 1856, 19/22 January 1866, 3 April 1881 and earthquake magnitude at 7.2±0.1 for Karaburun Peninsula 23 July 1949 produced tsunamis. The Chios-Cesme earth- and at 7.6±0.2 for the western part of the island of Chios. quake (1881, Mw 6.5) took place in the South of the Cesme Being famous for its historical heritage, this region is lo- strait while the Chios-Karaburun earthquake (1949, Mw 6.7) cated in the western part of the Gediz and Menderes graben occurred in the North. The tsunamis caused by the earth- systems and contains several morphologically prominent ac- quakes affected the coasts of Chios Island and Cesme. These tive normal faults with an approximate East-West strike. waves are thought to be associated with the earthquakes and Moreover, the NE-SW and NW-SE trending faults, with their co-seismic underwater failures possibly occurred along the changing kinematic characteristics from north to south, take coasts of the Chios Island and Karaburun Peninsula or on major roles on the tectonic regime of the region (Yilmaz, the complex subaqueous morphology between these lands. 1997). Some sea waves or oscillations observed following the after- Throughout history, earthquakes have been the most dam- shocks are believed to be related to other natural phenomena; aging natural disasters that have affected the area. There e.g. the seiches occurred mainly in open-narrow bays as trig- have been at least 15 disastrous earthquakes with magni- gered by the earthquakes. tudes greater than 6.0 reported in the literature. In the last two centuries, the event of Chios-Cesme on 3 April 1881 and the 23 July 1949 Chios-Karaburun event caused much damage. They caused many landslides along the coastal area 1 Introduction of Chios Island and the Karaburun Peninsula. Landsliding The coastal areas of the Aegean Sea have experienced is commonly triggered by any earthquake with a magnitude tsunamis many times in history. The generation mechanisms greater than 5; e.g. the 16 December 1977 Izmir earthquake and their characteristics have not been well described. Ac- (Mb=5.3; Eyidogan et al., 1991) triggered a landslide that cording to the historical information, or the distribution of caused the collapse of 750 houses (Wormsworth, 2003). The fault zones, volcanoes, and other probable tsunamigenic sea Chios-Cesme on 3 April 1881 and the 23 July 1949 Chios- bottom formations, there are numerous source areas which Karaburun earthquakes caused some sea waves which af- may be considered responsible for these tsunamis. Between fected the coasts of Chios Island and Cesme town, an impor- the North Anatolian fault zone in the North, and the Hel- tant tourism resort in the Karaburun Peninsula. The infor- lenic Arc in the South, one of the important source ar- mative sources for these tsunamis, however, are rather scarce eas of tsunamis in the Aegean region is the Chios (Sakiz)- and most of the documents are in ancient (Greek and Ot- Karaburun region (central Aegean Sea) (Fig. 1). This re- toman) languages. The scope of this study is to gather all possible informative Correspondence to: Y. Altinok data, to control or strengthen available information with new ([email protected]) evidences or facts gathered from several sources. Therefore 718 Y. Altinok et al.: Chios-Cesme Strait 1881 and 1949 earthquakes Figure 1. Map of the study region (see inset for location) showing bathymetry and place Fig.names 1.mentionedMap in of text. the Bathymetric study regiondata were (seeobtained inset by digitis foring location) 20-m contours show- of ing1:300,000 bathymetry scale British and Admiralty place and names1:75,000 scale mentioned Turkish governmental in text. charts. Bathymetric Figure 2. The principal (KF: Karaburun, UF: Urla) and other minor faults observed from both data were obtained by digitising 20-m contours of 1:300 000 scale Fig.satellite 2. imagesThe and principal site investigations (KF: Karaburun, extend NS in general. UF: Urla) On the and basis other of neotectonic minor British Admiralty and 1:75 000 scale Turkish governmental charts. faultsstudies observedand seismic activity from information, both satellite EW or imagesiented subaqueous and site faults investigations (CCF: Chios-Cesme ex- tendfault, CKF: NS inChios-Karaburun general. On fault) the should basis also of be neotectonic considered for possible studies source and locations seismic of activityChios-Cesme information, (3 April 1881) and EW Chios- orientedKaraburun subaqueous (23 July 1949) earthquakes. faults (CCF: Chios- we have analysed many historical records in the Ottoman Cesme fault, CKF: Chios-Karaburun fault) should also be consid- journals, which were recently opened to the public, as well ered for possible source locations of Chios-Cesme (3 April 1881) as international, modern Turkish and Ottoman journals, press and Chios-Karaburun (23 July 1949) earthquakes. reports and other relevant studies. Written documents helped us update available isoseismal maps to get an understanding of the origin of the events. Together with bathymetric data, troughs on land (Izmir and Menderes grabens) continue west geological settings, the (historical and instrumental) seismic into the Aegean basin (Mascle and Martin, 1990). activity of the region and satellite images, these maps were The Chios-Karaburun region, which is one of the most used to interpret the general features of these two typical seismically active parts of the Aegean Region, is situated events. 17 in western Turkey in the Izmir-Ankara Zone, to the South18 of the Sakarya Domain and to the North of the Menderes Massif. The region presents a complex geographical pro- 2 Geological frame file and is surrounded by an uneven sea and bays (Fig. 2). The north-south oriented Bozdag range (with its 1212 m high The Aegean Region is one of the most rapidly moving and Akdag peak) forms the backbone of the Karaburun Peninsula 2 seismically active parts of the Alphine-Himalayan Mountain (415 km ). Beyond localized plane areas (Mordogan, Yenil- Belt. The Aegean Plate is bound in the North by the west- iman, Badembuk¨ u¨ and Denizgiren), the mountains or steep ern extension of the North Anatolian Fault. The southern slopes fall directly into the sea in many places. The coastal boundary of the Aegean plate passes through the Hellenic line along the Izmir Bay and the northern and eastern shores Trench and the Pliny/Strabo complex, in the south of Crete of the Karaburun Peninsula are marked by many bays and and Rhodes (McKenzie, 1978). The main deformation in the coves. The Peninsula is also surrounded by a number of un- region arises from the N-S extension of the Aegean plate inhabited islands. To the West, there are a large number of which is due to subduction of the oceanic lithosphere un- Greek islands scattered in the Aegean Sea. Chios is one is- der the Aegean plate in the Hellenic Arc and the westward land in the Northeast Aegean archipelago. motion of the Anatolian plate. On the basis of GPS mea- The Chios-Karaburun region shows a very complex and surements, global kinematic models, the analysis of oceanic rapidly changing tectonic pattern due to the relative motions spreading, fault systems, and earthquake slip vectors; the of surrounding tectonic plates.