@article {Prouty2016a,
	title = {{Growth rates and ages of deep-sea corals impacted by the Deepwater Horizon oil spill}},
	journal = {Deep Sea Research Part II: Topical Studies in Oceanography},
	volume = {129},
	year = {2016},
	pages = {196{\textendash}212},
	abstract = {The impact of the April 2010 Deepwater Horizon (DWH) spill on deep-sea coral communities in the Gulf of Mexico (GoM) is still under investigation, as is the potential for these communities to recover. Impacts from the spill include observation of corals covered with flocculent material, with bare skeleton, excessive mucous production, sloughing tissue, and subsequent colonization of damaged areas by hydrozoans. Information on growth rates and life spans of deep-sea corals is important for understanding the vulnerability of these ecosystems to both natural and anthropogenic perturbations, as well as the likely duration of any observed adverse impacts. We report radiocarbon ages and radial and linear growth rates based on octocorals (Paramuricea spp. and Chrysogorgia sp.) collected in 2010 and 2011 from areas of the DWH impact. The oldest coral radiocarbon ages were measured on specimens collected 11 km to the SW of the oil spill from the Mississippi Canyon (MC) 344 site: 599 and 55 cal yr BP, suggesting continuous life spans of over 600 years for Paramuricea biscaya, the dominant coral species in the region. Calculated radial growth rates, between 0.34 $μ$m yr-1 and 14.20 $μ$m yr-1, are consistent with previously reported proteinaceous corals from the GoM. Anomalously low radiocarbon ($Δ$14C) values for soft tissue from some corals indicate that these corals were feeding on particulate organic carbon derived from an admixture of modern surface carbon and a low 14C carbon source. Results from this work indicate fossil carbon could contribute 5{\textendash}10{\%} to the coral soft tissue $Δ$14C signal within the area of the spill impact. The influence of a low 14C carbon source (e.g., petro-carbon) on the particulate organic carbon pool was observed at all sites within 30 km of the spill site, with the exception of MC118, which may have been outside of the dominant northeast{\textendash}southwest zone of impact. The quantitatively assessed extreme longevity and slow growth rates documented here highlight the vulnerability of these long-lived deep sea coral species to disturbance.},
	keywords = {HOV Alvin (Human Occupied Vehicle), ROV Jason (Remotely Operated Vehicle)},
	doi = {10.1016/j.dsr2.2014.10.021},
	author = {Prouty, N G and Fisher, C R and Demopoulos, A W J and Druffel, E R M}
}
@article {Prouty2016,
	title = {{Insights into methane dynamics from analysis of authigenic carbonates and chemosynthetic mussels at newly-discovered Atlantic Margin seeps}},
	journal = {Earth and Planetary Science Letters},
	volume = {449},
	year = {2016},
	pages = {332{\textendash}344},
	abstract = {The recent discovery of active methane venting along the US northern and mid-Atlantic margin represents a new source of global methane not previously accounted for in carbon budgets from this region. However, uncertainty remains as to the origin and history of methane seepage along this tectonically inactive passive margin. Here we present the first isotopic analyses of authigenic carbonates and methanotrophic deep-sea mussels, Bathymodiolus sp., and the first direct constraints on the timing of past methane emission, based on samples collected at the upper slope Baltimore Canyon (\~{}385 m water depth) and deepwater Norfolk (\~{}1600 m) seep fields within the area of newly-discovered venting. The authigenic carbonates at both sites were dominated by aragonite, with an average View the MathML source$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}
}
