Consulta: subjectFacets:"Sea of Marmara"
Registros recuperados: 18
Data/hora: 08/06/2024 10:26:06

Cold seeps along the main Marmara Fault in the Sea of Marmara (Turkey)
Provedor de dados: 5
Autores: Zitter, T; Henry, P; Aloisi, G; Delaygue, G; Cagatay, M; De Lepinay, B; Al Samir, M; Fornacciari, F; Tesmer, M; Pekdeger, A; Wallmann, K; Lericolais, Gilles.
The main Marmara Fault exhibits numerous sites of fluid venting, observed during previous cruises and in particular with R.O.V. VICTOR during the MARMARASCARPS cruise (2002). Long CALYPSO cores were recovered near active vents and at reference sites during the MARMARA-VT cruise (2004), together with echosounder sub-bottom profiles (frequency of 3.5kHz). We compiled R.O.V. video observations from MARMARASCARPS cruise and show that all known seeps occur in relationship with strike-slip faults, providing pathways for fluid migration. Among the main active sites, a distinction is made between gas seeps and water seeps. At gas seeps, bubble emissions at the seafloor or disturbed echofacies on sounder profiles demonstrate the presence of free methane gas at a...
Tipo: Text
Palavras-chave: High permeability pathways; Fault scarp; Seafloor observations; Cold seeps; Sea of Marmara.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4065.pdf

Nonseismic Signals in the Ocean: Indicators of Deep Sea and Seafloor Processes on Ocean‐Bottom Seismometer Data
Provedor de dados: 5
Autores: Batsi, Evangelia; Tsang‐hin‐sun, Eve; Klingelhoefer, Frauke; Bayrakci, Gaye; Chang, Emmy T.y.; Lin, Jing‐yi; Dellong, David; Monteil, Clément; Géli, Louis.
Ocean bottom seismometers (OBS) commonly record short duration events (SDEs), that could be described by all of these characteristics: (i) duration &lt; 1 s, (ii) one single‐wave train with no identified P‐ nor S‐wave arrivals and (iii) a dominant frequency usually between 4 Hz and 30 Hz. In many areas, SDEs have been associated with gas or fluid‐related processes near cold seeps or hydrothermal vents, although fish bumps, instrumental or current‐generated noise have been proposed as possible sources. In order to address some remaining issues, this study presents results from in situ and laboratory experiments combined with observations from 2 contrasting areas, the Sea of Marmara (Turkey) and the Chilean subduction zone. The in situ experiment was...
Tipo: Text
Palavras-chave: Marine seismology; Gas and fluid migration; Sea of Marmara; Chilean subduction.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00507/61895/65983.pdf

Distribution, morphology and triggers of submarine mass wasting in the Sea of Marmara
Provedor de dados: 5
Autores: Zitter, T. A. C.; Grall, Celine; Henry, Pierre; Ozeren, M.s.; Cagatay, M. Namik; Sengor, A.m.c.; Gasperini, Luca; Mercier De Lepinay, Marion; Geli, L.
An overview is given of mass wasting features along the slopes of the Sea of Marmara, Turkey, based on new data and previously published information. The Sea of Marmara is characterized by active tectonics along the North Anatolian Fault and by eustatic sea level changes controlling the connections both to the Mediterranean and Black Sea (i.e. lacustrine and marine conditions during sea-level low and high stands, respectively). High resolution bathymetric data, subsurface echo-sounder and seismic reflection profiling, seafloor visual observations, as well as stratigraphic analysis of sediment cores have been used to identify, map and date submarine slope failures and mass wasting deposits. Gravity mass movements are widespread on the steep slopes of the...
Tipo: Text
Palavras-chave: Sea of Marmara; Mass wasting; Seafloor morphology; Sea-level; Normal faulting.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00112/22351/20029.pdf

Free gas and gas hydrates from the Sea of Marmara, Turkey Chemical and structural characterization
Provedor de dados: 5
Autores: Bourry, Christophe; Chazallon, Bertrand; Charlou, Jean-luc; Donval, Jean-pierre; Ruffine, Livio; Henry, Pierre; Geli, Louis; Cagatay, M. Namik; Inan, Sedat; Moreau, Myriam.
Gas hydrates and gas bubbles were collected during the MARNAUT cruise (May-June 2007) in the Sea of Marmara along the North Anatolian Fault system, Turkey. Gas hydrates were sampled in the western part of the Sea of Marmara (on the Western High), and three gas-bubble samples were recovered on the Western High, the Central High (center part of the Sea of Marmara) and in the Cinarcik Basin (eastern part of the Sea of Marmara). Methane is the major component of hydrates (66.1%), but heavier gases such as C-2, C-3, and i-C-4 are also present in relatively high concentration. The methane contained within gas hydrate is clearly thermogenic as evidenced by a low C-1/C-2 + C-3 ratio of 3.3, and carbon and hydrogen isotopic data (delta C-13(CH4) of -44.1 parts per...
Tipo: Text
Palavras-chave: Isotopes; Thermogenic gas; Gas bubbles; Gas hydrate; Sea of Marmara.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6844.pdf

Pore water geochemistry at two seismogenic areas in the Sea of Marmara
Provedor de dados: 5
Autores: Ruffine, Livio; Germain, Yoan; Polonia, Alina; De Prunele, Alexis; Croguennec, Claire; Donval, Jean-pierre; Pitel-roudaut, Mathilde; Ponzevera, Emmanuel; Caprais, Jean-claude; Brandily, Christophe; Grall, Celine; Bollinger, Claire; Geli, Louis; Gasperini, Luca.
Within the Sea of Marmara, the highly active North Anatolian Fault (NAF) is responsible for major earthquakes (Mw&gt;=7), and acts as a pathway for fluid migration from deep sources to the seafloor. This work reports on pore water geochemistry from three sediment cores collected in the Gulfs of Izmit and Gemlik, along the Northern and the Middle strands of the NAF, respectively. The resulting data set shows that anaerobic oxidation of methane (AOM) is the major process responsible for sulfate depletion in the shallow sediment. In the Gulf of Gemlik, depth concentration profiles of both sulfate and alkalinity exhibit a kink-type profile. The Sulfate Methane Transition Zone (SMTZ) is located at moderate depth in the area. In the Gulf of Izmit, the low...
Tipo: Text
Palavras-chave: Anaerobic oxidation of methane; North Anatolian Fault; Pore water geochemistry; Sea of Marmara; Seismic activity.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00272/38339/36570.pdf

Improved detection and Coulomb stress computations for gas-related, shallow seismicity, in the Western Sea of Marmara
Provedor de dados: 5
Autores: Tary, Jean-baptiste; Géli, Louis; Lomax, Anthony; Batsi, Evangelia; Riboulot, Vincent; Henry, Pierre.
The Sea of Marmara (SoM) is a marine portion of the North Anatolian Fault (NAF) and a portion of this fault that did not break during its 20th century earthquake sequence. The NAF in the SoM is characterized by both significant seismic activity and widespread fluid manifestations. These fluids have both shallow and deep origins in different parts of the SoM and are often associated with the trace of the NAF which seems to act as a conduit. On July 25th, 2011, a 5 strike-slip earthquake occurred at a depth of about 11.5 km, triggering clusters of seismicity mostly located at depths shallower than 5 km, from less than a few minutes up to more than 6 days after the mainshock. To investigate the triggering of these clusters we first employ a match filter...
Tipo: Text
Palavras-chave: Shallow seismicity; Triggering; Stress transfer; North Anatolian Fault; Sea of Marmara.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00484/59522/62605.pdf

Geological and biological diversity of seeps in the Sea of Marmara
Provedor de dados: 5
Autores: Ondreas, Helene; Olu, Karine; Dupre, Stephanie; Scalabrin, Carla; Alix, Anne-sophie; Garrocq, Clément; Ruffine, Livio.
The Sea of Marmara hosts part of the North Anatolian Fault as an active submarine strike-slip fault. This area has suffered numerous earthquakes and presents a major seismic risk. Although the Sea of Marmara has been studied for many years, the link between geological morphostructures, the nature of fluids and biological communities is still rarely described. During the Marsite cruise (November 2014), dives with Remotely Operated Vehicle (ROV) VICTOR 6000 focused on detailed seafloor explorations of four different areas: the Central and Western highs and the Tekirdağ and Çinarcik basins. Based on 130 h of in situ videos, high-resolution seafloor mapping of seeps was conducted, emphasizing their significant geological and biological diversity from one...
Tipo: Text
Palavras-chave: Sea of Marmara; Cold seeps; Fluids; Seismogenic faults; Chemosynthetic fauna; Methane.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00624/73623/73040.pdf

Pore fluid chemistry of the North Anatolian Fault Zone in the Sea of Marmara: A diversity of sources and processes
Provedor de dados: 5
Autores: Tryon, M. D.; Henry, P.; Cagatay, M. N.; Zitter, T. A. C.; Geli, Louis; Gasperini, L.; Burnard, P.; Bourlange, S.; Grall, Celine.
As part of the 2007 Marnaut cruise in the Sea of Marmara, an investigation of the pore fluid chemistry of sites along the Main Marmara Fault zone was conducted. The goal was to define the spatial relationship between active faults and fluid outlets and to determine the sources and evolution of the fluids. Sites included basin bounding transtensional faults and strike-slip faults cutting through the topographic highs. The basin pore fluids are dominated by simple mixing of bottom water with a brackish, low-density Pleistocene Lake Marmara end-member that is advecting buoyantly and/or diffusing from a relatively shallow depth. This mix is overprinted by shallow redox reactions and carbonate precipitation. The ridge sites are more complex with evidence for...
Tipo: Text
Palavras-chave: Pore fluid; Fluid seeps; Marine hydrogeology; Methane seeps; Sea of Marmara; North Anatolian Fault.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00017/12809/9759.pdf

Gas occurrence and shallow conduit systems in the Western Sea of Marmara: a review and new acoustic evidence
Provedor de dados: 5
Autores: Saritas, Hakan; Cifci, Gunay; Geli, Louis; Thomas, Yannick; Marsset, Bruno; Henry, Pierre; Grall, Celine; Rochat, Alexis.
Based on 3D and 2D high-resolution multichannel seismic reflection data in the Western High-Sea of Marmara, this study reviews shallow gas occurrence and related structures and classifies gas conduit systems within the upper, few hundred meter-thick sediment layers below the seafloor. Acoustic anomalies including high amplitude-reverse polarity reflections (bright spots), low amplitude transparent zones, chaotic or discontinuous reflections, pull-down effects, and plumes in the water column are interpreted in terms of natural gas occurrence and fluid flow structures (e.g., mud volcanoes, pockmarks). The gas occurrence is thought to be mostly of thermogenic origin. Mud volcanoes are one of the primary gas conduits forming craters on the seabed due to...
Tipo: Text
Palavras-chave: Shallow gas; Gas conduit systems; Mud volcano; Pockmark; 2D-3D seismic; Western High; Sea of Marmara.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00456/56737/58689.pdf

Seafloor authigenic carbonate crusts along the submerged part of the North Anatolian Fault in the Sea of Marmara: Mineralogy, geochemistry, textures and genesis
Provedor de dados: 5
Autores: Cagatay, M. Namik; Yildiz, Guliz; Bayon, Germain; Ruffine, Livio; Henry, Pierre.
Extensive seafloor authigenic carbonate crusts occur as pavements, mounds and chimneys along the North Anatolian Fault System (NAFS) in the Sea of Marmara. They are often covered or surrounded by patches of black Fe-sulphide-rich sediments, and associated with hydrocarbon-rich gas and brackish-water emissions in the 1250 m-deep deep basins and with deep saline formation waters and hydrocarbons emissions from mud volcanoes and anticlines on the 350 to 650 m-deep compressional highs. The authigenic carbonate crusts are commonly porous with sinter-like, botryoidal and sugary- granular textures, and constructed from cementation of framework elements consisting mainly of bivalve shells and shell fragments, serpulid tubes, fibrous microbial organic matter and...
Tipo: Text
Palavras-chave: Authigenic carbonates; Mineral and isotopic compositions; Textures and structures; U-Th ages; North Anatolian Fault; Sea of Marmara.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00399/51047/51819.pdf

Paleo-environmental controls on cold seep carbonate authigenesis in the Sea of Marmara
Provedor de dados: 5
Autores: Cremiere, Antoine; Bayon, Germain; Ponzevera, Emmanuel; Pierre, Catherine.
The factors controlling fluid emission dynamics at ocean margins are poorly understood. In particular, there are significant uncertainties on how fluid seepage at cold seeps may have responded to abrupt environmental changes in the geological past. This study reports on a detailed geochemical investigation of seafloor carbonate crusts sampled at cold seeps along the submerged part of the North Anatolian Fault system in the Sea of Marmara - an inland sea, which has experienced major paleo-environmental changes over the last deglaciation period. We also analyzed a series of authigenic carbonate concretions recovered from two sediment cores at the Western-High ridge, an active fluid venting area. The ages of seafloor carbonate crusts derived from isochron...
Tipo: Text
Palavras-chave: U-Th dating; Authigenic carbonates; Sea of Marmara; Cold seeps; Sapropel event; Carbon and oxygen isotopes.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00161/27249/25488.pdf

Tectonic and sedimentary controls on widespread gas emissions in the Sea of Marmara: Results from systematic, shipborne multibeam echo sounder water column imaging
Provedor de dados: 5
Autores: Dupre, Stephanie; Scalabrin, Carla; Grall, Celine; Augustin, Jean-marie; Henry, Pierre; Sengor, A. M. Celal; Goeruer, Naci; Cagatay, M. Namik; Geli, Louis.
Understanding of the evolution of fluid-fault interactions during earthquake cycles is a challenge that acoustic gas emission studies can contribute. A survey of the Sea of Marmara using a shipborne, multibeam echo sounder, with water column records, provided an accurate spatial distribution of offshore seeps. Gas emissions are spatially controlled by a combination of factors, including fault and fracture networks in connection to the Main Marmara Fault system and inherited faults, the nature and thickness of sediments (e.g., occurrence of impermeable or gas-bearing sediments and landslides), and the connectivity between the seafloor and gas sources, particularly in relation to the Eocene Thrace Basin. The relationship between seepage and fault activity is...
Tipo: Text
Palavras-chave: Fluid emissions; Gas; Water column acoustics; Multibeam echo sounder; Sea of Marmara; Tectonics.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00268/37972/36049.pdf

Interpretation of Late‐Pleistocene/Holocene transition in the Sea of Marmara from geochemistry of bulk carbonates
Provedor de dados: 5
Autores: Liu, Yujia; Lu, Hailong; Yin, Xijie; Ruffine, Livio; Çağatay, M. Namik; Yang, Hailin; Chen, Chunqing; He, Dong; Zhu, Zhenli; Yalamaz, Burak.
Isotopic, mineralogical and elemental analyses have been conducted for the geochemical characteristics of the bulk carbonates in the sediment cores from the Western High and Çınarcık Basin in the Sea of Marmara to investigate the authigenic, biogenic and detrital components and their possible use in paleoceanographic studies. The Western High is a relatively shallow (‐500 to ‐800 m) compressional area characterized by relatively low sedimentation rates (30‐40 cm/kyr) whereas the Çnarcık Basin is a deep (~1250 m) transtentional area represented by high sedimentation rates (&gt;1 m/kyr). Both 87Sr/86Sr and δ18O of bulk carbonates from the Western High exhibit significant variations, increasing steeply from 87Sr/86Sr of 0.708437 to 0.708916 and δ18O of ‐3.2‰...
Tipo: Text
Palavras-chave: Bulk carbonates; Carbon and oxygen isotopes; Strontium isotopes; Transgression; Anaerobic biodegradation; Sea of Marmara.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00514/62518/66821.pdf

MARSITECruise Report. 2014 1st ‐ 13th November ‐ Leg 2
Provedor de dados: 5
Autores: Ruffine, Livio; Geli, Louis.
Summary of Marsitecruise The scientific cruise MARSITECRUISE of R/V Pourquoi pas? Took place from 28 October to 17 November 2014. Part of the operations were carried out within the frame of the MARSITE programme supported by the European Union, which aims at better understanding the behaviour of the North Anatolian fault in the Marmara sea in view of improving the assessment of the seismic hazard weighing on the Istanbul region. Coordinated by the Observatory of the University of Kandilli (KOERI, based in Istanbul), MARSITE groups 23 partners and includes different components: land, spatial and marine. The marine operations of the programme were coordinated by Ifremer and conducted using Italian (R/V Urania) and French (R/V Pourquoi pas?) naval means....
Tipo: Text
Palavras-chave: Sea of Marmara; Geochemistry; Seismicity.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00453/56480/58177.pdf

Sulfate-dependent anaerobic oxidation of methane at a highly dynamic bubbling site in the Eastern Sea of Marmara (Çinarcik Basin)
Provedor de dados: 5
Autores: Teichert, B. M. A.; Chevalier, N.; Gussone, N.; Bayon, Germain; Ponzevera, Emmanuel; Ruffine, Livio; Strauss, H.
During the MARSITECruise expedition in November 2014 on board the RV Pourquoi Pas?, multidisciplinary sampling was carried out with the ROV Victor 6000 in order to investigate biogeochemical processes taking place at cold seep environments in the Sea of Marmara. Pore water, bottom water, sediment and authigenic carbonate samples were collected from two short push cores (MRS-DV5-PC04 − 8 cm, MRS-DV5-PC01 − 12.5 cm) at an active methane bubbling site in the southeastern part of the Çinarcik Basin. Sulfate sulfur and oxygen isotope data as well as sulfide isotope data indicate that sulfate-dependent anaerobic oxidation of methane is the dominant process in the sediments. This is confirmed by archaeal lipids diagnostic for anaerobic methane oxidizers detected...
Tipo: Text
Palavras-chave: Sea of Marmara; Cinarcik Basin; Methane; Sulfate reduction; Anaerobic oxidation of methane; Authigenic carbonate; Lipid biomarker.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00413/52480/53267.pdf

Living (stained) deep-sea foraminifera from the Sea of Marmara: a preliminary study
Provedor de dados: 5
Autores: Fontanier, Christophe; Dissard, D.; Ruffine, Livio; Mamo, B.; Ponzevera, Emmanuel; Pelleter, Ewan; Baudin, F.; Roubi, Angelique; Cheron, Sandrine; Boissier, Audrey; Gayet, Nicolas; Bermell-fleury, S.; Pitel, M.; Guyader, Vivien; Lesongeur, Francoise; Savignac, F.
In this preliminary study, we investigate living (stained) foraminifera from the Sea of Marmara. We focus on the faunal composition and geochemical signatures (trace elements, carbon and oxygen stable isotopes) in foraminiferal tests at two deep-sea sites (329 and ~1240 m depth respectively). Documented by ROV observations and sampling, both study areas are heterogeneous (including bacterial mats and carbonate concretions), proximal to cold seeps and consist of dysoxic bottom water (O2&lt;20 µmol/L). The prevailing dysoxia at both study areas restricts foraminiferal diversity to very low values (S&lt;9, H’&lt;0.97). Stress-tolerant species Bolivina vadescens and Globobulimina affinis dominate living faunas at both sites. The highest foraminiferal standing...
Tipo: Text
Palavras-chave: Living (stained) benthic foraminifera; Sea of Marmara; Extreme ecosystems; Trace elements; Stable isotopes.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00416/52774/53646.pdf

Active fault segments along the North Anatolian Fault system in the Sea of Marmara: implication for seismic hazard
Provedor de dados: 5
Autores: Gasperini, Luca; Stucchi, Massimiliano; Cedro, Vincenzo; Meghraoui, Mustapha; Ucarkus, Gulsen; Polonia, Alina.
A new analysis of high-resolution multibeam and seismic reflection data, collected during several oceanographic expeditions starting from 1999, allowed us to compile an updated morphotectonic map of the North Anatolian Fault below the Sea of Marmara. We reconstructed kinematics and geometries of individual fault segments, active at the time scale of 10 ka, an interval which includes several earthquake cycles, taking as stratigraphic marker the base of the latest marine transgression. Given the high deformation rates relative to sediment supply, most active tectonic structures have a morphological expression at the seafloor, even in presence of composite fault geometries and/or overprinting due to mass-wasting or turbidite deposits. In the frame of the...
Tipo: Text
Palavras-chave: North Anatolian fault; Sea of Marmara; Earthquakes; Active fault segments; Marine geophysics; Seismic hazard.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00684/79575/82244.pdf

Multiple gas reservoirs are responsible for the gas emissions along the Marmara fault network
Provedor de dados: 5
Autores: Ruffine, Livio; Donval, Jean-pierre; Croguennec, Claire; Burnard, Pete; Lu, Hailong; Germain, Yoan; Legoix, Ludovic N.; Bignon, Laurent; Cagatay, M. Namik; Marty, Bernard; Madre, David; Pitel-roudaut, Mathilde; Henry, Pierre; Geli, Louis.
On continental margins, upward migration of fluids from various sources and various subsurface accumulations, through the sedimentary column to the seafloor, leads to the development of cold seeps where chemical compounds are discharged into the water column. MarsiteCruise was undertaken in November 2014 to investigate the dynamics of cold seeps characterized by vigorous gas emissions in the Sea of Marmara (SoM). A previous paper published by Bourry et al. (2009) presented the gas geochemistry of three seeps sampled along three different segments in the SoM. Their findings showed that the seeps were sourced by three different reservoirs. In this paper, seventeen seeps were investigated to determine the gas sources, unravel reservoir contributions, and...
Tipo: Text
Palavras-chave: Abiotic CO2-source; Gas bubbles; Molecular and isotopic compositions; Primary and secondary methanogenesis; Sea of Marmara; Seeps; Thermogenic gases.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00411/52203/52926.pdf