@article {Prouty2016,
	title = {{Insights into methane dynamics from analysis of authigenic carbonates and chemosynthetic mussels at newly-discovered Atlantic Margin seeps}},
	journal = {Earth and Planetary Science Letters},
	volume = {449},
	year = {2016},
	pages = {332{\textendash}344},
	abstract = {The recent discovery of active methane venting along the US northern and mid-Atlantic margin represents a new source of global methane not previously accounted for in carbon budgets from this region. However, uncertainty remains as to the origin and history of methane seepage along this tectonically inactive passive margin. Here we present the first isotopic analyses of authigenic carbonates and methanotrophic deep-sea mussels, Bathymodiolus sp., and the first direct constraints on the timing of past methane emission, based on samples collected at the upper slope Baltimore Canyon (\~{}385 m water depth) and deepwater Norfolk (\~{}1600 m) seep fields within the area of newly-discovered venting. The authigenic carbonates at both sites were dominated by aragonite, with an average View the MathML source$δ$C13 signature of -47{\textperthousand}-47{\textperthousand}, a value consistent with microbially driven anaerobic oxidation of methane-rich fluids occurring at or near the sediment{\textendash}water interface. Authigenic carbonate U and Sr isotope data further support the inference of carbonate precipitation from seawater-derived fluids rather than from formation fluids from deep aquifers. Carbonate stable and radiocarbon (View the MathML source$δ$C13 and View the MathML source$Δ$C13) isotope values from living Bathymodiolus sp. specimens are lighter than those of seawater dissolved inorganic carbon, highlighting the influence of fossil carbon from methane on carbonate precipitation. U{\textendash}Th dates on authigenic carbonates suggest seepage at Baltimore Canyon between 14.7{\textpm}0.6 ka14.7{\textpm}0.6 ka to 15.7{\textpm}1.6 ka15.7{\textpm}1.6 ka, and at the Norfolk seep field between 1.0{\textpm}0.7 ka1.0{\textpm}0.7 ka to 3.3{\textpm}1.3 ka3.3{\textpm}1.3 ka, providing constraint on the longevity of methane efflux at these sites. The age of the brecciated authigenic carbonates and the occurrence of pockmarks at the Baltimore Canyon upper slope could suggest a link between sediment delivery during Pleistocene sea-level lowstand, accumulation of pore fluid overpressure from sediment compaction, and release of overpressure through subsequent venting. Calculations show that the Baltimore Canyon site probably has not been within the gas hydrate stability zone (GHSZ) in the past 20 ka, meaning that in-situ release of methane from dissociating gas hydrate cannot be sustaining the seep. We cannot rule out updip migration of methane from dissociation of gas hydrate that occurs farther down the slope as a source of the venting at Baltimore Canyon, but consider that the history of rapid sediment accumulation and overpressure may play a more important role in methane emissions at this site.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	doi = {10.1016/j.epsl.2016.05.023},
	author = {Prouty, N G and Sahy, D and Ruppel, C D and Roark, E B and Condon, D and Brooke, S and Ross, S W and Demopoulos, A W J}
}
@article {Brothers2013,
	title = {{Evidence for extensive methane venting on the southeastern U.S. Atlantic margin}},
	journal = {Geology},
	volume = {41},
	number = {7},
	year = {2013},
	month = {jul},
	pages = {807{\textendash}810},
	abstract = {We present the first evidence for widespread seabed methane venting along the southeastern United States Atlantic margin beyond the well-known Blake Ridge diapir seep. Recent ship- and autonomous underwater vehicle (AUV)-collected data resolve multiple water-column anomalies ({\textgreater}1000 m height) and extensive new chemosynthetic seep communities at the Blake Ridge and Cape Fear diapirs. These results indicate that multiple, highly localized fluid conduits punctuate the areally extensive Blake Ridge gas hydrate province, and enable the delivery of significant amounts of methane to the water column. Thus, there appears to be an abundance of seabed fluid flux not previously ascribed to the Atlantic margin of the United States.},
	keywords = {AUV Sentry (Autonomous Underwater Vehicle)},
	issn = {0091-7613},
	doi = {10.1130/G34217.1},
	author = {Brothers, L L and Van Dover, C L and German, C R and Kaiser, C L and Yoerger, D R and Ruppel, C D and Lobecker, E and Skarke, A D and Wagner, J K S}
}
@article {Heyl2007,
	title = {{Characteristics of vesicomyid clams and their environment at the Blake Ridge cold seep, South Carolina, USA}},
	journal = {Marine Ecology Progress Series},
	volume = {339},
	year = {2007},
	pages = {169{\textendash}184},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0171-8630},
	doi = {10.3354/meps339169},
	url = {http://dx.doi.org/10.3354/meps339169},
	author = {Heyl, T P and Gilhooly, W P and Chambers, R M and Gilchrist, G W and Macko, S A and Ruppel, C D and Van Dover, C L}
}
@article {Hornbach2007,
	title = {{Three-dimensional structure of fluid conduits sustaining an active deep marine cold seep}},
	journal = {Geophysical Research Letters},
	volume = {34},
	number = {5},
	year = {2007},
	pages = {L05601},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0094-8276},
	doi = {10.1029/2006gl028859},
	url = {http://dx.doi.org/10.1029/2006gl028859},
	author = {Hornbach, M J and Ruppel, C D and Van Dover, C L}
}
