@article {Larson2015,
	title = {{Stealth export of hydrogen and methane from a low temperature serpentinization system}},
	journal = {Deep-Sea Research Part II: Topical Studies in Oceanography},
	volume = {121},
	year = {2015},
	pages = {233{\textendash}245},
	abstract = {Chemical input to the deep sea from hydrothermal systems is a globally distributed phenomenon. Hydrothermal discharge is one of the primary mechanisms by which the Earth{\textquoteright}s interior processes manifest themselves at the Earth{\textquoteright}s surface, and it provides a source of energy for autotrophic processes by microbes that are too deep to capitalize on sunlight. Much is known about the water-column signature of this discharge from high-temperature mid-ocean Ridge (MOR) environments and their neighboring low-temperature counterparts. Hydrothermal discharge farther away from the ridge, however, has garnered less attention, owing in part to the difficulty in finding this style of venting, which eludes methods of detection that work well for high-temperature {\textquoteleft}black smoker{\textquoteright}-type venting. Here we present a case study of the plume from one such {\textquoteleft}invisible{\textquoteright} off-axis environment, The Lost City, with an emphasis on the dissolved volatile content of the hydrothermal plume. Serpentinization and abiotic organic synthesis generate significant concentrations of H2 and CH4 in vent fluid, but these species are unevenly transported to the overlying plume, which itself appears to be a composite of two different sources. A concentrated vent cluster on the talus slope channels fluid through at least eight chimneys, producing a water-column plume with the highest observed concentrations of CH4 in the field. In contrast, a saddle in the topography leading up to a carbonate cap hosts broadly distributed, nearly invisible venting apparent only in its water-column signals of redox potential and dissolved gas content, including the highest observed plume H2. After normalizing H2 and CH4 to the 3He background-corrected anomaly (3He$Δ$) to account for mixing and relative amount of mantle input, it appears that, while a minimum of 60{\%} of CH4 is transported out of the system, greater than 90{\%} of the H2 is consumed in the subsurface prior to venting. The exception to this pattern occurs in the plume originating from the area dubbed Chaff Beach, in which somewhat more than 10{\%} of the original H2 remains, indicating that this otherwise unremarkable plume, and others like it, may represent a significant source of H2 to the deep sea.},
	keywords = {AUV ABE (Autonomous Benthic Explorer), HOV Alvin (Human Occupied Vehicle)},
	doi = {10.1016/j.dsr2.2015.05.007},
	author = {Larson, B I and Lang, S Q and Lilley, M D and Olson, E J and Lupton, J E and Nakamura, K and Buck, N J}
}
@article {German2010,
	title = {{Diverse styles of submarine venting on the ultraslow spreading Mid-Cayman Rise}},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {107},
	number = {32},
	year = {2010},
	month = {aug},
	pages = {14020{\textendash}14025},
	abstract = {Thirty years after the first discovery of high-temperature submarine venting, the vast majority of the global mid-ocean ridge remains unexplored for hydrothermal activity. Of particular interest are the world{\textquoteright}s ultraslow spreading ridges that were the last to be demonstrated to host high-temperature venting but may host systems particularly relevant to prebiotic chemistry and the origins of life. Here we report evidence for previously unknown, diverse, and very deep hydrothermal vents along the similar to 110 km long, ultraslow spreading Mid-Cayman Rise (MCR). Our data indicate that the MCR hosts at least three discrete hydrothermal sites, each representing a different type of water-rock interaction, including both mafic and ultramafic systems and, at similar to 5,000 m, the deepest known hydrothermal vent. Although submarine hydrothermal circulation, in which seawater percolates through and reacts with host lithologies, occurs on all mid-ocean ridges, the diversity of vent types identified here and their relative geographic isolation make the MCR unique in the oceans. These new sites offer prospects for an expanded range of vent-fluid compositions, varieties of abiotic organic chemical synthesis and extremophile microorganisms, and unparalleled faunal biodiversity-all in close proximity.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0027-8424},
	doi = {10.1073/pnas.1009205107},
	author = {German, C R and Bowen, A and Coleman, M L and Honig, D L and Huber, J A and Jakuba, M V and Kinsey, J C and Kurz, M D and Leroy, S and McDermott, J M and de Lepinay, B M and Nakamura, K and Seewald, J S and Smith, J L and Sylva, S P and Van Dover, C L and Whitcomb, L L and Yoerger, D R}
}
