@article {Lin2016,
	title = {{Linkages between mineralogy, fluid chemistry, and microbial communities within hydrothermal chimneys from the Endeavour Segment, Juan de Fuca Ridge}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {17},
	year = {2016},
	pages = {300{\textendash}323},
	abstract = {Rock and fluid samples were collected from three hydrothermal chimneys at the Endeavour Segment, Juan de Fuca Ridge to evaluate linkages among mineralogy, fluid chemistry, and microbial community composition within the chimneys. M{\"o}ssbauer, midinfrared thermal emission, and visible-near infrared spectroscopies were utilized for the first time to characterize vent mineralogy, in addition to thin-section petrography, X-ray diffraction, and elemental analyses. A 282{\textdegree}C venting chimney from the Bastille edifice was composed primarily of sulfide minerals such as chalcopyrite, marcasite, and sphalerite. In contrast, samples from a 300{\textdegree}C venting chimney from the Dante edifice and a 321{\textdegree}C venting chimney from the Hot Harold edifice contained a high abundance of the sulfate mineral anhydrite. Geochemical modeling of mixed vent fluids suggested the oxic-anoxic transition zone was above 100{\textdegree}C at all three vents, and that the thermodynamic energy available for autotrophic microbial redox reactions favored aerobic sulfide and methane oxidation. As predicted, microbes within the Dante and Hot Harold chimneys were most closely related to mesophilic and thermophilic aerobes of the Betaproteobacteria and Gammaproteobacteria and sulfide-oxidizing autotrophic Epsilonproteobacteria. However, most of the microbes within the Bastille chimney were most closely related to mesophilic and thermophilic anaerobes of the Deltaproteobacteria, especially sulfate reducers, and anaerobic hyperthermophilic archaea. The predominance of anaerobes in the Bastille chimney indicated that other environmental factors promote anoxic conditions. Possibilities include the maturity or fluid flow characteristics of the chimney, abiotic Fe2+ and S2- oxidation in the vent fluids, or O2 depletion by aerobic respiration on the chimney outer wall.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	doi = {10.1002/2015GC006091},
	author = {Lin, T J and Ver Eecke, H C and Breves, E A and Dyar, M D and Jamieson, J W and Hannington, M D and Dahle, H and Bishop, J L and Lane, M D and Butterfield, D A and Kelley, D S and Lilley, M D and Baross, J A and Holden, J F}
}
@article {ISI:000345545100011,
	title = {{The Anatomy of a Buried Submarine Hydrothermal System, Clark Volcano, Kermadec Arc, New Zealand}},
	journal = {ECONOMIC GEOLOGY},
	volume = {109},
	number = {8},
	year = {2014},
	month = {dec},
	pages = {2261{\textendash}2292},
	type = {Article},
	abstract = {Clark volcano of the Kermadec arc, northeast of New Zealand, is a large stratovolcano comprised of two coalescing volcanic cones; an apparently younger, more coherent, twin-peaked edifice to the northwest and a relatively older, more degraded and tectonized cone to the southeast. High-resolution water column surveys show an active hydrothermal system at the summit of the NW cone largely along a ridge spur connecting the two peaks, with activity also noted at the head of scarps related to sector collapse. Clark is the only known cone volcano along the Kermadec arc to host sulfide mineralization. Volcano-scale gravity and magnetic surveys over Clark show that it is highly magnetized, and that a strong gravity gradient exists between the two edifices. Modeling suggests that a crustal-scale fault lies between these two edifices, with thinner crust beneath the NW cone. Locations of regional earthquake epicenters show a southwest-northeast trend bisecting the two Clark cones, striking northeastward into Tangaroa volcano. Detailed mapping of magnetics above the NW cone summit shows a highly magnetized ring structure 350 m below the summit that is not apparent in the bathymetry; we believe this structure represents the top of a caldera. Oblate zones of low (weak) magnetization caused by hydrothermal fluid upflow, here termed burn holes, form a pattern in the regional magnetization resembling Swiss cheese. Presumably older burn holes occupy the inner margin of the ring structure and show no signs of hydrothermal activity, while younger burn holes are coincident with active venting on the summit. A combination of mineralogy, geochemistry, and seafloor mapping of the NW cone shows that hydrothermal activity today is largely manifest by widespread diffuse venting, with temperatures ranging between 56 degrees and 106 degrees C. Numerous, small ({\textless}= 30 cm high) chimneys populate the summit area, with one site host to the similar to 7-m-tall {\textquoteleft}{\textquoteleft}Twin Towers{\{}{\textquoteright}{\textquoteright}{\}} chimneys with maximum vent fluid temperatures of 221 degrees C (pH 4.9), consistent with delta S-34(anhydrite-pyrite) values indicating formation temperatures of similar to 228 degrees to 249 degrees C. Mineralization is dominated by pyrite-marcasite-barite-anhydrite. Radiometric dating using the Ra-228/Ra-226 and Ra-226/Ba methods shows active chimneys to be {\textless}20 with most {\textless}2 years old. However, the chimneys at Clark show evidence for mixing with, and remobilizing of, barite as old as 19,000 years. This is consistent with Nd and Sr isotope compositions of Clark chimney and sulfate crust samples that indicate mixing of similar to 40{\%} seawater with a vent fluid derived from low K lavas. Similarly, REE data show the hydrothermal fluids have interacted with a plagioclase-rich source rock. A holistic approach to the study of the Clark hydrothermal system has revealed a two-stage process whereby a caldera-forming volcanic event preceded a later cone-building event. This ensured a protracted (at least 20 ka yrs) history of hydrothermal activity and associated mineral deposition. If we assume at least 200-m-high walls for the postulated (buried) caldera, then hydrothermal fluids would have exited the seafloor 20 ka years ago at least 550 m deeper than they do today, with fluid discharge temperatures potentially much hotter (similar to 350 degrees C). Subsequent to caldera infilling, relatively porous volcaniclastic and other units making up the cone acted as largescale filters, enabling ascending hydrothermal fluids to boil and mix with seawater subseafloor, effectively removing the metals (including remobilized Cu) in solution before they reached the seafloor. This has implications for estimates for the metal inventory of seafloor hydrothermal systems pertaining to arc hydrothermal systems.},
	keywords = {AUV ABE (Autonomous Benthic Explorer), AUV Sentry (Autonomous Underwater Vehicle)},
	issn = {0361-0128},
	author = {de Ronde, C E J and Walker, S L and Ditchburn, R G and Tontini, F Caratori and Hannington, M D and Merle, S G and Timm, C and Handler, M R and Wysoczanski, R J and Dekov, V M and Kamenov, G D and Baker, E T and Embley, R W and Lupton, J E and Stoffers, P}
}
@article {Jamieson2014,
	title = {{Hydrothermal sulfide accumulation along the Endeavour Segment, Juan de Fuca Ridge}},
	journal = {Earth and Planetary Science Letters},
	volume = {395},
	year = {2014},
	month = {jan},
	pages = {136{\textendash}148},
	abstract = {Hydrothermal sulfide deposits that form on the seafloor are often located by the detection of hydrothermal plumes in the water column, followed by exploration with deep-towed cameras, side-scan sonar imaging, and finally by visual surveys using remotely-operated vehicle or occupied submersible. Hydrothermal plume detection, however, is ineffective for finding hydrothermally-inactive sulfide deposits, which may represent a significant amount of the total sulfide accumulation on the seafloor, even in hydrothermally active settings. Here, we present results from recent high-resolution, autonomous underwater vehicle-based mapping of the hydrothermally-active Endeavour Segment of the Juan de Fuca Ridge, in the Northeast Pacific Ocean. Analysis of the ridge bathymetry resulted in the location of 581 individual sulfide deposits along 24 km of ridge length. Hydrothermal deposits were distinguished from volcanic and tectonic features based on the characteristics of their surface morphology, such as shape and slope angles. Volume calculations for each deposit results in a total volume of 372,500 m3 of hydrothermal sulfide{\textendash}sulfate{\textendash}silica material, for an equivalent mass of \~{}1.2 Mt of hydrothermal material on the seafloor within the ridge{\textquoteright}s axial valley, assuming a density of 3.1 g/cm3. Much of this total volume is from previously undocumented inactive deposits outside the main active vent fields. Based on minimum ages of sulfide deposition, the deposits accumulated at a maximum rate of \~{}400 t/yr, with a depositional efficiency (proportion of hydrothermal material that accumulates on the seafloor to the total amount hydrothermally mobilized and transported to the seafloor) of \~{}5{\%}. The calculated sulfide tonnage represents a four-fold increase over previous sulfide estimates for the Endeavour Segment that were based largely on accumulations from within the active fields. These results suggest that recent global seafloor sulfide resource estimates, which were based mostly on the sizes and distribution of hydrothermally-active deposits, may be similarly underestimating the amount of sulfide along the global submarine neovolcanic zones.},
	keywords = {AUV ABE (Autonomous Benthic Explorer), HOV Alvin (Human Occupied Vehicle), ROV Jason (Remotely Operated Vehicle)},
	issn = {0012-821X},
	doi = {10.1016/j.epsl.2014.03.035},
	url = {http://www.sciencedirect.com/science/article/pii/S0012821X14001873},
	author = {Jamieson, J W and Clague, D A and Hannington, M D}
}
@article {Jamieson2013,
	title = {{Sulfide geochronology along the Endeavour Segment of the Juan de Fuca Ridge}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {14},
	number = {7},
	year = {2013},
	pages = {2084{\textendash}2099},
	abstract = {Forty-nine hydrothermal sulfide-sulfate rock samples from the Endeavour Segment of the Juan de Fuca Ridge, northeastern Pacific Ocean, were dated by measuring the decay of 226Ra (half-life of 1600 years) in hydrothermal barite to provide a history of hydrothermal venting at the site over the past 6000 years. This dating method is effective for samples ranging in age from \~{}200 to 20,000 years old and effectively bridges an age gap between shorter- and longer-lived U-series dating techniques for hydrothermal deposits. Results show that hydrothermal venting at the active High Rise, Sasquatch, and Main Endeavour fields began at least 850, 1450, and 2300 years ago, respectively. Barite ages of other inactive deposits on the axial valley floor are between \~{}1200 and \~{}2200 years old, indicating past widespread hydrothermal venting outside of the currently active vent fields. Samples from the half-graben on the eastern slope of the axial valley range in age from \~{}1700 to \~{}2925 years, and a single sample from outside the axial valley, near the westernmost valley fault scarp is \~{}5850 {\textpm} 205 years old. The spatial relationship between hydrothermal venting and normal faulting suggests a temporal relationship, with progressive younging of sulfide deposits from the edges of the axial valley toward the center of the rift. These relationships are consistent with the inward migration of normal faulting toward the center of the valley over time and a minimum age of onset of hydrothermal activity in this region of 5850 years.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	doi = {10.1002/ggge.20133},
	author = {Jamieson, J W and Hannington, M D and Clague, D A and Kelley, D S and Delaney, J R and Holden, J F and Tivey, M K and Kimpe, L E}
}
@article {Kristall2006,
	title = {{Growth history of a diffusely venting sulfide structure from the Juan de Fuca Ridge: A petrological and geochemical study}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {7},
	year = {2006},
	pages = {Q07001},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {1525-2027},
	doi = {10.1029/2005GC001166},
	url = {http://dx.doi.org/10.1029/2005GC001166},
	author = {Kristall, B and Kelley, D S and Hannington, M D and Delaney, J R}
}
@article {Rona1996,
	title = {{Heat flow and mineralogy of TAG relict high-temperature hydrothermal zones: Mid-Atlantic Ridge 26 degrees N, 45 degrees W}},
	journal = {Geophysical Research Letters},
	volume = {23},
	number = {23},
	year = {1996},
	pages = {3507{\textendash}3510},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0094-8276},
	doi = {10.1029/96GL03257},
	url = {http://dx.doi.org/10.1029/96GL03257},
	author = {Rona, P A and Petersen, S and Becker, K and Von Herzen, R P and Hannington, M D and Herzig, P M and Naka, J and Lalou, C and Thompson, G}
}
@article {Tivey1995,
	title = {{Deducing patterns of fluid flow and mixing within the TAG hydrothermal mound using mineralogical and geochemical data}},
	journal = {Journal of Geophysical Research},
	volume = {100},
	number = {B7},
	year = {1995},
	pages = {12,512{\textendash}527,555},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0148-0227},
	doi = {10.1029/94GL02081},
	url = {http://dx.doi.org/10.1029/94GL02081},
	author = {Tivey, M K and Humphris, S E and Thompson, G and Hannington, M D and Rona, P A}
}
@article {Rona1994,
	title = {{Alvin zone of the TAG hydrothermal field, Mid-Atlantic Ridge 26 N, 45 W}},
	journal = {EOS, Transactions, American Geophysical Union},
	volume = {75},
	number = {44 (Fall Meet. Suppl.)},
	year = {1994},
	pages = {706},
	issn = {0096-3941},
	author = {Rona, P A and Petersen, S and Hannington, M D and Herzig, P M and Tivey, M A and Kleinrock, M and Humphris, S E and Thompson, G and Lalou, C}
}
@article {Rona1993,
	title = {{Active and relict sea-floor hydorthermal mineralization at the TAG hydrothermal field, Mid-Atlantic Ridge}},
	journal = {Economic Geology},
	volume = {88},
	number = {8},
	year = {1993},
	pages = {1989{\textendash}2017},
	issn = {0361-0128},
	doi = {10.2113/gsecongeo.88.8.1989},
	url = {http://dx.doi.org/10.2113/gsecongeo.88.8.1989},
	author = {Rona, P A and Hannington, M D and Raman, C V and Thompson, G and Tivey, M K and Humphris, S E and Lalou, C and Petersen, S}
}
