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3. Seamounts and Seamount-Like Structures of the Tyrrhenian

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3. Seamounts and Seamount-Like Structures of the Tyrrhenian Sea Marzia Rovere Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy Marzia Bo, Jessica Alessi, Chiara Paoli, Natasha Villani, Paolo Vassallo DISTAV, Università di Genova Corso Europa 26, 16132 Genova, Italy Cristina Fiori “MENKAB: il respiro del mare” Association Via Quarda Superiore, 20/6 17100 Savona, Italy and DISTAV, Università di Genova Corso Europa 26, 16132 Genova, Italy Nicolò Roccatagliata, “MENKAB: il respiro del mare” Association Via Quarda Superiore, 20/6 17100 Savona, Italy 111 ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES Table 3: Seamounts and Seamount-Like Structures of the Tyrrhenian Sea. Seamount name Lat. ° Long. ° Peak depth (m) Base depth (m) Page Aceste - Tiberio Seamount 38.41736 11.51683 120-130 790-800 115 Albano Seamount 41.35898 12.05938 250-260 580-590 116 Albatros - Cicerone Seamount 40.39669 13.18365 1390-1400 2300-2310 117 Alcione Seamount 39.27159 15.29632 920-930 1750-1760 118 Anchise Seamount 38.69209 12.82098 510-520 1140-1150 119 Augusto Seamount 39.12990 12.49610 1950-1960 2240-2250 120 Baronie - K Seamount 40.60155 10.23650 160-170 1310-1320 121 Casoni Seamount 38.73095 15.19070 1040-1050 1120-1130 123 Cassinis Seamount 40.76766 11.71696 1090-1100 1680-1690 124 Catullo Seamount 39.35610 12.91848 2880-2890 3190-3200 125 Cialdi Seamount 41.84720 10.59555 300-310 1210-1220 126 Cornacya Seamount 39.11126 10.23771 1240-1250 1530-1540 127 Cornaglia Seamount 39.70234 10.65460 1030-1040 2520-2530 128 D’Ancona Ridge 39.93411 12.12106 2710-2720 3320-3330 129 De Marchi Seamount 40.22975 12.26260 2360-2370 3390-3400 130 Diamante Seamount 39.65667 15.30437 400-410 700-710 131 Drepano Seamount 38.61323 12.22538 460-470 710-720 132 Enarete Seamount 38.64233 14.00036 320-330 1650-1660 133 Enea Seamount 39.44368 11.74133 2850-2860 3220-3230 134 Enotrio Seamount 39.50153 15.34239 290-300 740-750 135 Eolo Seamount 38.56311 14.15862 640-650 1360-1370 136 Etruschi Seamount 41.66705 10.36715 310-320 990-1000 137 Farfalle Seamount 40.43822 12.47504 2450-2460 3140-3150 138 Finale structure High 38.30456 14.15919 800-810 1280-1290 139 Flavio Gioia Seamount 40.04247 13.04610 2100-2110 2900-2910 140 Giulio Cesare - Caesar Seamount 38.61729 11.44669 1150-1160 1610-1620 141 Garibaldi - Glauco Seamount 39.10907 13.78836 1770-1780 2370-2380 142 Glabro Seamount 39.51302 15.16295 850-860 1190-1200 143 Gortani Ridge 40.27171 12.46722 3110-3120 3460-3470 144 Ichnusa Seamount 38.75063 9.58249 190-200 960-970 145 Issel Seamount 39.68378 13.66253 1910-1920 2650-2660 146 Lametino 1 Seamount 39.05503 15.39613 950-960 1810-1820 147 Lametino 2 Seamount 39.00910 15.32143 1370-1380 2140-2150 147 Lucrezio Seamount 38.97996 13.25028 2680-2690 3310-3320 148 Major Seamount 39.69708 11.28346 2060-2070 2790-2800 149 Magnaghi - V.Emanuele Seamount 39.90917 11.77930 1530-1540 3140-3150 150 Marsili - Plinio Seamount 39.28405 14.39681 570-580 3170-3180 151 Marussi Seamount 40.60884 10.56331 1040-1050 1520-1530 152 Monte della Rondine 40.22161 11.67480 1950-1960 2370-2380 153 112 TYRRHENIAN SEA Seamount name Lat. Long. Peak depth (m) Base depth (m) Page Orazio Seamount 39.33150 13.41620 3000-3010 3330-3340 154 Ovidio Seamount 39.55649 15.46812 240-250 370-380 155 Palinuro-Strabo Seamount 39.48455 14.82892 70-80 1570-1580 156 Pompeo Seamount 38.59667 11.80853 1040-1050 1300-1310 158 Poseidon Seamount 39.72609 13.83795 1640-1650 2140-2150 159 Prometeo Seamount 38.62567 13.46877 1830-1840 2140-2150 160 Quirra Seamount 39.31691 10.32088 890-900 1590-1600 161 Sallustio Seamount 39.75541 10.91509 2410-2420 2730-2740 162 San Vito Ridge 38.32516 12.85033 580-590 720-730 163 Sardinia Seamount 40.02648 10.13769 1190-1200 1460-1470 164 Scuso Seamount 38.26734 12.55012 87 290-300 165 Secchi - Adriano Seamount 40.44694 11.70386 1220-1230 2420-2430 166 Sele Seamount 40.29675 14.20890 240-250 720-730 167 Selli Line Seamount 40.23431 11.76898 1980-1990 2370-2380 168 Sirene Seamount 40.25926 13.92116 660-670 1050-1060 169 Sisifo Seamount 38.78828 13.85064 1080-1090 2010-2020 170 Solunto Structural High 38.41578 13.74908 700-710 1320-1330 171 Tacito Seamount 40.18627 13.56702 1150-1160 1520-1530 172 Tiberino Seamount 41.66814 11.54940 290-300 770-780 173 Tibullo Seamount 39.76375 12.83646 3070-3080 3540-3550 174 Tito Livio Seamount 39.35462 10.91430 2270-2280 2660-2670 175 Traiano Seamount 38.98816 12.22970 1920-1930 2290-2300 176 Vavilov Seamount 39.85498 12.61264 820-830 3150-3160 177 Vercelli Seamount 41.10792 10.90581 60-70 1000-1010 178 Vespasiano Seamount 38.79367 12.76689 1530-1540 1850-1860 180 Virgilio Seamount 39.30674 12.51836 2650-2660 3040-3050 181 113 ATLAS OF THE MEDITERRANEAN SEAMOUNTS AND SEAMOUNT–LIKE STRUCTURES Seamounts and Seamount-Like Structures of the Tyrrhenian Sea: general map. 42 Cialdi Tiberino Etruschi Albano Vercelli Cassinis Baronie/K Secchi/Adriano Marussi Farfalla Albatros/Cicerone Selli Gortani Sirene Monte della Rondine De Marchi Sele Flavio Gioia Tacito V.Emanuele/Magnaghi 40 Sardinia Vavilov Sallustio D'Ancona Poseidone Major Diamante Cornaglia Tibullo Issel Glabro Ovidio Palinuro/Strabo Tito Livio Catullo Orazio Quirra Enea Virgilio Enotrio Marsili/Plinio Alcione Augusto Lametino 1 Lucrezio Cornacya Traiano Garibaldi/Glauco Vespasiano Lametino 2 Ichnusa Sisifo Enarete G.Cesare/Caesar Drepano Anchise Casoni Prometeo Pompeo Eolo San Vito Aceste/Tiberio Solunto Scuso Finale 38 8 10 12 14 16 170 km The Tyrrhenian Sea is a complex sea area, not only due to the rift- former continental faulted blocks of the conjugate margins, the west- ing stage occurring within the slow convergence between Africa and ern Sardinian and the eastern Latium-Campanian in the north, and Europe, but also because all happened in a very restricted area and the Sicilian and Calabrian margins in the south. The opening of the very limited time frame, that is the main reason why it hosts such Tyrrhenian Sea was probably caused by a slab roll-back of the old a large number of seamounts, compared to the other sea regions. and dense Ionian oceanic crust subducting towards the NW under The opening started about 10 Ma in its NW corner (Vavilov Basin), NE Sicily and the Calabrian Arc (Malinverno and Ryan, 1986). The the Calabrian and Peloritan massifs began to separate from the Sar- deep magmas generated an overlying volcanism that formed the dinia block to create the Tyrrhenian basin. Soon after the rifting and Aeolian Arc and other seamounts located in the southern Tyrrhenian oceanization migrated to the SE towards the Marsili Basin, where Sea. The rock composition thus reflects the position of the structures ocean crust is believed to have been emplaced between 2 Ma and within the geodynamic context, the time when they were formed and a few hundreds of thousands years ago (Sartori, 2005b). Most of roughly ranges from intraplate (oceanic and MORB-like tholeiitic, the seamounts are therefore the result of Plio-Quaternary volcanism, Na-alkaline) to arc-type magmatism (arc-tholeiitic, calc-alkaline, po- associated with continental stretching and mantle upwelling or are tassic) to very old cristalline basement (Kastens et al., 1988). 114 TYRRHENIAN SEA STRUCTURE: Aceste - Tiberio Seamount Location: 38.41736°N – 11.51683°E Peak depth (m): 120-130 Base depth (m): 790-800 18 km DESCRIPTION: Life on and around the Seamount Geology The rich benthonic communities of the Aceste Seamount have been recently re- vealed by a ROV survey (Aguilar et al., 2013). Numerous vulnerable rocky bottom The Aceste Seamount is a 60-km-long ridge made ecosystems have been observed, such as cold water coral reefs (Desmophyllum of magmas of the Oceanic Island Basalt-type (Serri dianthus, Stenocyathus vermiformis, Caryophyllia spp., Pourtalosmilia anthophyl- et al., 2001). Aceste was emplaced ~ 5 Ma and then lites, Javania caileti, Anomocora fecunda, Dendrophyllia spp.) and coral gardens magmatism progressed to the E together with the (Paramuricea spp., Eunicella spp., Viminella flagellum, Callogorgia verticillata, E-SE migration of the Ionian subduction zone. The Acanthogorgia spp., Placogorgia coronata, Swiftia pallida, Muriceides lepida, northern flank of the Seamount is affected by an Villogorgia bebrycoides, Bebryce mollis, Nicella granifera). Also rich soft bot- amphitheatre-like depression possibly reflecting a tom assemblages have been recorded made of gorgonians and pennatulaceans sector collapse. Accordingly, the positive magnetic (Isidella elongata, Pennatula spp., Pteroeides spinulosum, Virgularia mirabilis, anomaly, registered over the Aceste Seamount, may Veretillum cynomorium, Kophobelemnon stelliferum, Funiculina quadrangula- be related to the seamount plumbing system denu- ris) together with crinoids beds (Leptometra phalangium) and brachiopod beds dated by the collapse of the northern flank (De Ritis (Gryphus vitreus) on detritic bottoms. A previous ROV survey conducted on the et al., 2010). The Aceste Seamount corresponds with Aceste Seamount reported also the occasional presence of large antipatharian the Tiberio Seamount in Finetti and Del Ben (1986). corals and frequent patches of the yellow scleractinian Dendrophyllia cornigera (Freiwald et al., 2011). The same survey reported also plenty trawled coral colo- nies and lost fishing gear. The Aceste Seamount is an area of high importance for elasmobranchs. In fact, various protected elasmobranches have been reported around the Aceste Seamount (Oxynotus centrina, Centrophorus granulosus, Leucoraja circularis, Cetorhinus maximus, Squalus acanthias, Carcharodon carcharias and Squalus blainvillei) (Aguilar et al., 2013; Baino et al., 2010).
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    Gas seeps and gas hydrates in the Amazon deep-sea fan Joao Marcelo Ketzer, Adolpho Augustin, Luiz Frederico Rodrigues, Rafael Oliveira, Daniel Praeg, Maria Alejandra Gomez Pivel, Antonio Tadeu dos Reis, Cleverson Silva, Bruno Leonel To cite this version: Joao Marcelo Ketzer, Adolpho Augustin, Luiz Frederico Rodrigues, Rafael Oliveira, Daniel Praeg, et al.. Gas seeps and gas hydrates in the Amazon deep-sea fan. Geo-Marine Letters, Springer Verlag, 2018, 38 (5), pp.429-438. 10.1007/s00367-018-0546-6. hal-02196115 HAL Id: hal-02196115 https://hal.archives-ouvertes.fr/hal-02196115 Submitted on 9 Oct 2020 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. Geo-Marine Letters (2018) 38:429–438 https://doi.org/10.1007/s00367-018-0546-6 ORIGINAL Gas seeps and gas hydrates in the Amazon deep-sea fan Joao Marcelo Ketzer1,2 & Adolpho Augustin1 & Luiz Frederico Rodrigues1 & Rafael Oliveira1 & Daniel Praeg1,3 & 4 Maria Alejandra Gomez Pivel & Antonio Tadeu dos Reis5 & Cleverson Silva6 & Bruno Leonel7 Received: 10 January 2018 /Accepted: 2 August 2018 /Published online: 17 August 2018 # The Author(s) 2018 Abstract Deep-sea fans have been proposed to act as carbon sinks, rapid deposition driving shallow methanogenesis to favor net storage within the gas hydrate stability zone (GHSZ).
  • 54. Mesozoic–Tertiary Tectonic Evolution of the Easternmost Mediterranean Area: Integration of Marine and Land Evidence1

    54. Mesozoic–Tertiary Tectonic Evolution of the Easternmost Mediterranean Area: Integration of Marine and Land Evidence1

    Robertson, A.H.F., Emeis, K.-C., Richter, C., and Camerlenghi, A. (Eds.), 1998 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 160 54. MESOZOIC–TERTIARY TECTONIC EVOLUTION OF THE EASTERNMOST MEDITERRANEAN AREA: INTEGRATION OF MARINE AND LAND EVIDENCE1 Alastair H.F. Robertson2 ABSTRACT This paper presents a synthesis of Holocene to Late Paleozoic marine and land evidence from the easternmost Mediterra- nean area, in the light of recent ODP Leg 160 drilling results from the Eratosthenes Seamount. The synthesis is founded on three key conclusions derived from marine- and land-based study over the last decade. First, the North African and Levant coastal and offshore areas represent a Mesozoic rifted continental margin of Triassic age, with the Levantine Basin being under- lain by oceanic crust. Second, Mesozoic ophiolites and related continental margin units in southern Turkey and Cyprus repre- sent tectonically emplaced remnants of a southerly Neotethyan oceanic basin and are not far-travelled units derived from a single Neotethys far to the north. Third, the present boundary of the African and Eurasian plates runs approximately east-west across the easternmost Mediterranean and is located between Cyprus and the Eratosthenes Seamount. The marine and land geology of the easternmost Mediterranean is discussed utilizing four north-south segments, followed by presentation of a plate tectonic reconstruction for the Late Permian to Holocene time. INTRODUCTION ocean (Figs. 2, 3; Le Pichon, 1982). The easternmost Mediterranean is defined as that part of the Eastern Mediterranean Sea located east ° The objective here is to integrate marine- and land-based geolog- of the Aegean (east of 28 E longitude).