@article {Hensen01042015,
	title = {{Strike-slip faults mediate the rise of crustal-derived fluids and mud volcanism in the deep sea}},
	journal = {Geology},
	volume = {43},
	number = {4},
	year = {2015},
	pages = {339{\textendash}342},
	abstract = {We report on newly discovered mud volcanoes located at \~{}4500 m water depth \~{}90 km west of the deformation front of the accretionary wedge of the Gulf of Cadiz, and thus outside of their typical geotectonic environment. Seismic data suggest that fluid flow is mediated by a >400-km-long strike-slip fault marking the transcurrent plate boundary between Africa and Eurasia. Geochemical data (Cl, B, Sr, 87Sr/86Sr, $δ$18O, $δ$D) reveal that fluids originate in oceanic crust older than 140 Ma. On their rise to the surface, these fluids receive strong geochemical signals from recrystallization of Upper Jurassic carbonates and clay-mineral dehydration in younger terrigeneous units. At present, reports of mud volcanoes in similar deep-sea settings are rare, but given that the large area of transform-type plate boundaries has been barely investigated, such pathways of fluid discharge may provide an important, yet unappreciated link between the deeply buried oceanic crust and the deep ocean.},
	doi = {10.1130/G36359.1},
	url = {http://geology.gsapubs.org/content/43/4/339.abstract},
	author = {Hensen, Christian and Scholz, Florian and Nuzzo, Marianne and Valadares, Vasco and Gr{\'a}cia, Eul{\`a}lia and Terrinha, Pedro and Liebetrau, Volker and Kaul, Norbert and Silva, Sonia and Mart{\'\i}nez-Loriente, Sara and Bartolom{\'e}, Rafael and Pi{\~n}ero, Elena and Magalh{\~a}es, Vitor H and Schmidt, Mark and Weise, Stephan M and Cunha, Marina and Hilario, Ana and Perea, Hector and Rovelli, Lorenzo and Lackschewitz, Klas}
}
@article {Larrasoana2007,
	title = {{Diagenetic formation of greigite and pyrrhotite in gas hydrate marine sedimentary systems}},
	journal = {Earth and Planetary Science Letters},
	volume = {261},
	number = {3-4},
	year = {2007},
	pages = {350{\textendash}366},
	abstract = {Mineral magnetic results and electron microscope observations from gas hydrate-bearing marine sediments cored at southern Hydrate Ridge during Ocean Drilling Program Leg 204 (Sites 1244 to 1252, Cascadia Margin, offshore Oregon) demonstrate that authigenic greigite and pyrrhotite formed as a byproduct of microbially-mediated diagenetic reactions in the sulphate, the anaerobic oxidation of methane (AOM), and the methanic/gas hydrate zones. Geochemical conditions favourable for formation and preservation of greigite and pyrrhotite appear to be a limited source of sulphide, whether it derives from microbially-driven sulphate reduction in the sulphate zone, in the AOM zone or in deep sediments undergoing AOM, so that pyritization reactions are not driven to completion. Our results indicate that rock magnetic identification of greigite and pyrrhotite should be useful for detecting ancient gas hydrate systems in the marine sedimentary record, because it can enable rapid screening of ancient sediments for potential horizons where methane and disseminated gas hydrates might have occurred. Formation of authigenic greigite and pyrrhotite at different depths within the gas hydrate stability zone also implies that the magnetization of the host sediments will have been acquired at variable times, which is likely to compromise paleomagnetic results from greigite- and pyrrhotite-bearing marine sediments. {\textcopyright} 2007 Elsevier B.V. All rights reserved.},
	keywords = {anaerobic oxidation of methane, diagenesis, gas hydrate, greigite, iron sulphide, marine sediments, methane, mineral magnetism, pyrrhotite, siderite, sulphate reduction},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2007.06.032},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-34548475090\&partnerID=tZOtx3y1},
	author = {Larrasoa{\~n}a, Juan C. and Roberts, Andrew P. and Musgrave, Robert J. and Gr{\'a}cia, Eul{\`a}lia and Pi{\~n}ero, Elena and Vega, Marta and Mart{\'\i}nez-Ruiz, Francisca}
}
@article {Pinero2007,
	title = {{Gas hydrate disturbance fabrics of southern Hydrate Ridge sediments (ODP Leg 204): Relationship with texture and physical properties}},
	journal = {Geo-Marine Letters},
	volume = {27},
	number = {2-4},
	year = {2007},
	pages = {279{\textendash}288},
	abstract = {Soupy and mousse-like fabrics are disturbance sedimentary features that result from the dissociation of gas hydrate, a process that releases water. During the core retrieval process, soupy and mousse-like fabrics are produced in the gas hydrate-bearing sediments due to changes in pressure and temperature conditions. Therefore, the identification of soupy and mousse-like fabrics can be used as a proxy for the presence of gas hydrate in addition to other evidence, such as pore water freshening or anomalously cool temperature. We present here grain-size results, mineralogical composition and magnetic susceptibility data of soupy and mousse-like samples from the southern Hydrate Ridge (Cascadia accretionary complex) acquired during Leg 204 of the Ocean Drilling Program. In order to study the relationship between sedimentary texture and the presence of gas hydrates, we have compared these results with the main textural and compositional data available from the same area. Most of the disturbed analyzed samples from the summit and the western flank of southern Hydrate Ridge show a mean grain size coarser than the average mean grain size of the hemipelagic samples from the same area. The depositional features of the sediments are not recognised due to disturbance. However, their granulometric statistical parameters and distribution curves, and magnetic susceptibility logs indicate that they correspond to a turbidite facies. These results suggest that gas hydrates in the southern Hydrate Ridge could form preferentially in coarser grain-size layers that could act as conduits feeding gas from below the BSR. Two samples from the uppermost metres near the seafloor at the summit of the southern Hydrate Ridge show a finer mean grain-size value than the average of hemipelagic samples. They were located where the highest amount of gas hydrates was detected, suggesting that in this area the availability of methane gas was high enough to generate gas hydrates, even within low-permeability layers. The mineralogical composition of the soupy and mousse-like sediments does not show any specific characteristic with respect to the other samples from the southern Hydrate Ridge. {\textcopyright} Springer-Verlag 2007.},
	issn = {0276-0460},
	doi = {10.1007/s00367-007-0077-z},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-34250188050\&partnerID=tZOtx3y1},
	author = {Pi{\~n}ero, Elena and Gr{\'a}cia, Eul{\`a}lia and Mart{\'\i}nez-Ruiz, Francisca and Larrasoa{\~n}a, Juan Cruz and Vizcaino, Alexis and Ercilla, Gemma}
}
