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IUCN Atlas of the Mediterranean Seamounts

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IUCN Atlas of the Mediterranean Seamounts ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES 226 5. Seamounts and Seamount-like Structures of the Eastern Mediterranean Bayram Öztürk Istanbul Univesity, Faculty of Fisheries Ordu Caddesi 200, Laleli, Istanbul and Turkish Marine Research Foundation Marzia Rovere Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy and Maurizio Würtz DISTAV, Università di Genova Corso Europa 26, 16132 Genova, Italy Acknowledgements: The Authors are indebted to Dr. Nur Eda Topçu for her valuable help. 227 ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES Table 5: Seamounts and Seamount-Like Structures of the East Mediterranean. Seamout name Lat. ° Long. ° Peak depth (m) Base depth (m) Page Alkyoni Bank 38.22130 25.56280 60-70 410-420 230 Anamur-Kormakiti Ridge ND ND ND ND 231 Anaxagoras Seamount 35.67566 30.51171 920-930 1510-1520 233 Anaximander-Finike Seamount 35.50840 29.78160 1110-1120 2000-2010 234 Anaximenes Seamount 35.43070 30.16420 690-700 1500-1510 235 Aphroditi Bank 39.70040 24.53820 150-160 290-300 236 Balıkçı Bank 37.91021 25.99832 40-50 330-340 237 Bilim Bank 36.36251 34.44887 40-50 250-260 238 Brouker and Stokes Banks 38.87820 25.39500 70-80 200-210 239 Danaos-2007 Seamount 34.66586 25.54216 450-460 780-790 240 Eratosthenes Seamount 33.74444 32.73362 780-790 1920-1930 241 Florence Rise 34.82090 31.69151 1560-1570 2100-2110 243 Glavki Bank 39.61340 24.45670 110-120 320-330 236 Gűzelyurt Seamount 35.67092 32.76268 1410-1420 ND 231 Hecataeus Rise 34.44201 34.34533 1090-1100 1510-1520 244 Hecataeus Knoll 34.44025 33.61840 190-200 690-700 244 Ira and Navtilos Banks 38.67146 24.24609 40-50 260-270 245 Karpas Ridge 35.88444 34.88554 50-60 360-370 246 Kaş Bank 35.58756 29.33301 91 ND 247 Kolumbo Volcano 36.52070 25.47170 10-20 280-290 248 Larnaka Ridge 35.27495 35.09294 840-850 ND 249 Latakia Ridge 35.13782 35.54911 890-900 ND 250 Literi Bank 38.81486 24.85928 70-80 210-220 251 Mansel and Johnston Banks 39.29600 25.38780 30-40 190-200 252 West Mediterranean Ridge 33.77267 22.70907 1150-1160 2190-2200 253 East Mediterranean Ridge 34.95354 27.46288 350-360 1240-1250 253 Ptolemy Seamount 34.62513 24.56142 1050-1060 1820-1830 255 Sinaya Bank 38.86362 25.78698 70-80 210-220 256 Turgut Reis Bank 35.02200 35.01300 1110-1120 1350-1360 257 Venus Bank 40.23870 25.02910 150-160 350-360 258 Yunus Bank 37.14237 26.25719 100-110 300-310 259 228 EASTERN MEDITERRANEAN East Mediterranean Seamounts and Banks: general map. Venus 40 Aphroditi Glavki Mansel-Johnston Brouker-Stokes Literi Sinaya Ira-Navtilos Alkyoni Balikçi 38 Yunus Kolumbo Bilim Karpas 36 Anaxagoras Anamur-Kornakiti Anaximander-Finike Larnaka Anaximenes Florence Turgut Reis Latakia East Mediterranean rdg Danaos-2007 (Nameless) Ptolemy Hecataeus knoll Hecataeus rise 34 West Mediterranean rdg Eratosthenes 32 24 26 28 30 32 34 36 180 km The Eastern Mediterranean comprises the Cretan Sea, the Aegean The Messinian Salinity Crisis led to the deposition of 1.5 km of Sea and the Levantine Sea. The Eastern Mediterranean Sea formed evaporites in the Levantine Basin, which overall contains up to 10 during the tectonic break-up of the Pangea Supercontinent starting km of sediment. During the Pliocene, accretionary activity along the about 270 Ma to 180 Ma, that led to continental crust stretching and external front, due the ongoing convergence of Africa towards the thinning, with the formation of several grabens, where very thick Aegean Arc, led to the formation of the Mediterranean Ridge (Finetti, sedimentary sequences deposited (Biju-Duval and Montadert, 1976), with active mud diapirism. Huge piles of sediments containing 1977). When Africa and Europe started to converge, the region evaporites, strike-slip movements and compression, volcanism, salt experienced strike-slip faulting and inversion of those previously tectonics and gravitational processes are all concurrent causes for formed grabens. When 18-14 Ma subduction started in the Aegean the formation of seamounts in this sea region. region, the Hellenic Arc formed and extension began in its back-arc region, due to slab tearing (Jolivet et al., 1994). The external non- volcanic arc now consists of a raised topographic feature running the full length of the Hellenic arc, forming the uplifted islands of Crete and Rhodes. The inner southern volcanic arc consists of a series of dormant or active volcanoes, including the Kolumbo Seamount. 229 ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES STRUCTURE: Alkyoni Bank Location: 38.22130°N – 25.56280°E Peak depth (m): 60-70 Base depth (m): 410-420 DESCRIPTION: Geology No specific geological or geographical information is available on this structure, which is depicted in this map: http://highsea.cz/map/GM06.JPG Life on and around the Seamount Some coralligenous species have been detected such as the sponge Spongia of- ficinalis, and the crustaceans Palinurus elephas and Homarus vulgaris. Besides, Scillarus arctus was also reported during the summer 2007 cruises in the Aegean Sea. This bank offers a suitable habitat for lobsters due to the occurrence of patchy and fragmented rocky substrates (Ozturk, 2007). No information about the Alkyoni Bank pelagic communities has been found in the scientific literature. 18 km 230 EASTERN MEDITERRANEAN STRUCTURE: Anamur Kormakiti Ridge and Güzelyurt Seamount Anamur Kormakiti Ridge (ANM) Location: ND Peak depth (m): ND Base depth (m): ND Güzelyurt Seamount (GZL)* Location: 35.67092°N – 32.76268°E Peak depth (m): 1410-1420 Base depth (m): ND * Source: http://www.geomapapp.org/database/GEBCO/GEBCO_gazetteer.htm DESCRIPTION: Geology The Anamur-Kormakiti Ridge is a prominent N-S oriented structural high with a thick cover of Plio-Quaternary sediment: it is probably a fault lineament, which bounds the Cilicia-Adana Basin, to the east, and the Antalya Basin, to the west (Robertson, 1998b). The Anamur–Kormakiti Ridge is characterized by an imbri- GZL cate fold-thrust system. The older structures appear to be truncated by a promi- nent E-W trending normal fault system, which at least locally affects the Plio- Quaternary sequences along much of the Turkish slope of the Cilicia Basin. West of Anamur–Kormakiti Ridge, the thick Plio-Quaternary sediments, on the strongly dissected slope, have been affected by N–S trending normal faults and display a block and graben morphology (Ozel et al., 2007). ANM Life on and around the Seamount Large unexploited commercial sponge communities (mainly Spongia officinalis) have been discovered during two summer surveys (2007 and 2008) conducted in these sites. Scillarus arctus and Scillarus latus were also reported. A lot of pur- seiner fishing nets have been found in these areas as a ghost fishing. The area of the Güzelyurt Seamount is represented by the submarine channel between Turkey and Cyprus, it is located on migratory routes of large and small pelagic fish in the Levantine Basin (Öztürk, 2009a). Besides, it is a spawning ground of bullet tuna (Auxis rochei) and Atlantic skipjack (Euthynnus allettera- tus). Along the Turkish coasts, nestling beaches of the endangered loggerhead turtle (Caretta caretta) and green turtle (Chelonia mydas) are present (Gücü and Öztürk, 2010). Bluefin tuna spawning area has been demonstrated to be located 9 km between Turkey and Cyprus islands (Karakulak et al., 2004). This area was pro- posed as High Seas MPA (Öztürk, 2009a) and remains within the determined EBSAs (UNEP-MAP-RAC/SPA, 2010). 231 ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES STRUCTURE: Anaximander Mountains Complex (Anaxagoras, Anaximander, Anaximenes Seamounts) The Anaximander Mountains Complex (Anaxagoras, Anaximander or Finike and This area was suggested as a High Seas MPA Anaximenes Seamounts) is located between the Hellenic and Cyprus arcs and (Öztürk, 2009a) and later as a potential SPAMI was formed in large part due to the ongoing convergence of the African and (Öztürk et al., 2012b). Turkish government has de- Anatolian plates. A protracted interval of contraction in the Miocene created a clared as Special Protected Area on 16th August series of broadly east-west trending and predominantly south-verging structures 2013 (official gazetteer number 28737: http://www. across the entire eastern Mediterranean, among them there are the Anaximander resmigazete.gov.tr/eskiler/2013/08/20130816-3. Mountains. The absence of the Messinian evaporites in the Anaximander htm). OCEANA cited the area among the EBSAs in Mountains and in the adjacent deep basins, Rhodes Basin (more than 4000 the Mediterranean due to the above cited character- m-deep) and Finike Basin (3000 m-deep), indicates that the southward thrust- istics as well as the presence of large migratory fish ing of the Anaximander Mountains occurred in post-Messinian time (Dimitrov and cetaceans (OCEANA, 2014). and Woodside, 2003; Zitter, 2004). During the mid-Tortonian, the last phase of thrusting coincided with the onset of a different kinematic regime related to the westward rotation of the Anatolian plate. This Late Miocene change marked the start of differential subsidence that resulted in the formation of the Anaximander Mountains, which are thus characterized by strong contractional/transpressional deformation (ten Veen et al., 2004). During the Plio–Quaternary, the Anaximander Seamount and the Anaximenes Seamount developed as the result of uplift and rotation of a thrust fan. At this time, the Anaximenes Seamount experienced a progressive counterclockwise rotation, while the Anaxagoras Seamount and the Florence Rise experienced a clockwise rotation creating the present-day arrowhead-shaped morphology of the Anaximander Mountains. An arcuate fault separates the Anaximenes and Anaxagoras Seamounts from the Anaximander Seamount (Aksu et al., 2009).
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