@article {schwing_organic_2023,
	title = {Organic carbon and planktic foraminifera radiocarbon derived Holocene sediment accumulation rates in the northern slopes of the Gulf of Mexico},
	journal = {Deep Sea Research Part I: Oceanographic Research Papers},
	volume = {193},
	year = {2023},
	month = {03/2023},
	pages = {103959},
	abstract = {In the context of climate regulation and anthropogenic waste detoxification (e.g. oil spills), estimates of deep ocean sedimentation and carbon sequestration are of the utmost importance. Radiocarbon (14C) is a common radioisotope that can be used to establish millennial scale sediment accumulation rates. The objectives of this study were to: 1) establish ages for co-occurring total organic carbon (TOC) and planktic foraminifera (carbonate) in the northeastern Gulf of Mexico (GoM), 2) use these ages to estimate accumulation rates independently, 3) identify any evidence of redistribution, and 4) examine any offset between TOC and carbonate 14C ages as a tool to potentially identify selective TOC transport. Sediment samples were collected in May 2018 from the RV Point Sur using an Ocean Instruments MC-800 multi corer. Radiocarbon measurements of both planktic foraminifera and TOC subsamples were made at the National Ocean Science Accelerator Mass Spectrometry Facility (NOSAMS). Radiocarbon ages, calibrated using the OxCal 4.4, ranged from recent to 6407 BP. Linear (LAR: 4{\textendash}24~cm/kyr) and mass accumulation rates (MAR: 1.5{\textendash}11.5~g/cm2/kyr) were generally consistent with those reported by other recent studies in the GoM. At two sites, C14 ages decreased from the surface to the second sampling increment which was consistent with sediment redistribution. The TOC-carbonate offsets, which are indicative of lateral advection and organic matter aging, were lower than those found in the majority of other regions, which was consistent with less lateral transport or a more oligotrophic setting. The magnitude in radiocarbon age offsets with depth could potentially be used as a relative aging or transport assessment tool in areas with little resuspension.},
	keywords = {accumulation rates, Foraminifera, Gulf of Mexico, radiocarbon, Radiogeochemistry},
	issn = {0967-0637},
	doi = {10.1016/j.dsr.2022.103959},
	url = {https://www.sciencedirect.com/science/article/pii/S0967063722002722},
	author = {Schwing, Patrick and Chanton, Jeffrey and Bosman, Samantha and Brooks, Gregg and Larson, Rebekka A. and Romero, Isabel and Diercks, Arne}
}
@article {2480,
	title = {Using Natural Abundance Radiocarbon To Trace the Flux of Petrocarbon to the Seafloor Following the Deepwater Horizon Oil Spill},
	journal = {Environmental Science \& Technology},
	volume = {49},
	year = {2015},
	month = {Aug-01-2016},
	pages = {847 - 854},
	abstract = {In 2010, the Deepwater Horizon accident released 4.6{\textendash}6.0 {\texttimes} 1011 grams or 4.1 to 4.6 million barrels of fossil petroleum derived carbon (petrocarbon) as oil into the Gulf of Mexico. Natural abundance radiocarbon measurements on surface sediment organic matter in a 2.4 {\texttimes} 1010 m2 deep-water region surrounding the spill site indicate the deposition of a fossil-carbon containing layer that included 1.6 to 2.6 {\texttimes} 1010 grams of oil-derived carbon. This quantity represents between 0.5 to 9.1\% of the released petrocarbon, with a best estimate of 3.0{\textendash}4.9\%. These values may be lower limit estimates of the fraction of the oil that was deposited on the seafloor because they focus on a limited mostly deep-water area of the Gulf, include a conservative estimate of thickness of the depositional layer, and use an average background or prespill radiocarbon value for sedimentary organic carbon that produces a conservative value. A similar approach using hopane tracer estimated that 4{\textendash}31\% of 2 million barrels of oil that stayed in the deep sea settled on the bottom. Converting that to a percentage of the total oil that entered into the environment (to which we normalized our estimate) converts this range to 1.8 to 14.4\%. Although extrapolated over a larger area, our independent estimate produced similar values.},
	issn = {0013-936X},
	doi = {10.1021/es5046524},
	url = {http://pubs.acs.org/doi/abs/10.1021/es5046524http://pubs.acs.org/doi/pdf/10.1021/es5046524},
	author = {Chanton, Jeffrey and Zhao, Tingting and Rosenheim, Brad E. and Joye, Samantha and Bosman, Samantha and Brunner, Charlotte and Yeager, Kevin M. and Diercks, Arne R. and Hollander, David}
}
@article {68,
	title = {Using Natural Abundance Radiocarbon To Trace the Flux of Petrocarbon to the Seafloor Following the Deepwater Horizon Oil Spill},
	journal = {Environmental science \& technology},
	year = {2014},
	abstract = {In 2010, the Deepwater Horizon accident released 4.6?6.0 ? 1011 grams or 4.1 to 4.6 million barrels of fossil petroleum derived carbon (petrocarbon) as oil into the Gulf of Mexico. Natural abundance radiocarbon measurements on surface sediment organic matter in a 2.4 ? 1010 m2 deep-water region surrounding the spill site indicate the deposition of a fossil-carbon containing layer that included 1.6 to 2.6 ? 1010 grams of oil-derived carbon. This quantity represents between 0.5 to 9.1\% of the released petrocarbon, with a best estimate of 3.0?4.9\%. These values may be lower limit estimates of the fraction of the oil that was deposited on the seafloor because they focus on a limited mostly deep-water area of the Gulf, include a conservative estimate of thickness of the depositional layer, and use an average background or prespill radiocarbon value for sedimentary organic carbon that produces a conservative value. A similar approach using hopane tracer estimated that 4?31\% of 2 million barrels of oil that stayed in the deep sea settled on the bottom. Converting that to a percentage of the total oil that entered into the environment (to which we normalized our estimate) converts this range to 1.8 to 14.4\%. Although extrapolated over a larger area, our independent estimate produced similar values.; In 2010, the Deepwater Horizon accident released 4.6?6.0 ? 1011 grams or 4.1 to 4.6 million barrels of fossil petroleum derived carbon (petrocarbon) as oil into the Gulf of Mexico. Natural abundance radiocarbon measurements on surface sediment organic matter in a 2.4 ? 1010 m2 deep-water region surrounding the spill site indicate the deposition of a fossil-carbon containing layer that included 1.6 to 2.6 ? 1010 grams of oil-derived carbon. This quantity represents between 0.5 to 9.1\% of the released petrocarbon, with a best estimate of 3.0?4.9\%. These values may be lower limit estimates of the fraction of the oil that was deposited on the seafloor because they focus on a limited mostly deep-water area of the Gulf, include a conservative estimate of thickness of the depositional layer, and use an average background or prespill radiocarbon value for sedimentary organic carbon that produces a conservative value. A similar approach using hopane tracer estimated that 4?31\% of 2 million barrels of oil that stayed in the deep sea settled on the bottom. Converting that to a percentage of the total oil that entered into the environment (to which we normalized our estimate) converts this range to 1.8 to 14.4\%. Although extrapolated over a larger area, our independent estimate produced similar values.},
	issn = {0013-936X},
	doi = {10.1021/es5046524},
	url = {http://dx.doi.org/10.1021/es5046524},
	author = {Chanton, Jeffrey and Zhao, Tingting and Rosenheim, Brad E. and Joye, Samantha and Bosman, Samantha and Brunner, Charlotte and Yeager, Kevin M. and Diercks, Arne R. and Hollander, David}
}
@article {2488,
	title = {Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers},
	journal = {Nature Geoscience},
	volume = {5},
	year = {2012},
	month = {Aug-05-2013},
	pages = {419 - 426},
	abstract = {Methane, a potent greenhouse gas, accumulates in subsurface hydrocarbon reservoirs, such as coal beds and natural gas deposits. In the Arctic, permafrost and glaciers form a {\textquoteleft}cryosphere cap{\textquoteright} that traps gas leaking from these reservoirs, restricting flow to the atmosphere. With a carbon store of over 1,200 Pg, the Arctic geologic methane reservoir is large when compared with the global atmospheric methane pool of around 5 Pg. As such, the Earth{\textquoteright}s climate is sensitive to the escape of even a small fraction of this methane. Here, we document the release of 14C-depleted methane to the atmosphere from abundant gas seeps concentrated along boundaries of permafrost thaw and receding glaciers in Alaska and Greenland, using aerial and ground surface survey data and in situ measurements of methane isotopes and flux. We mapped over 150,000 seeps, which we identified as bubble-induced open holes in lake ice. These seeps were characterized by anomalously high methane fluxes, and in Alaska by ancient radiocarbon ages and stable isotope values that matched those of coal bed and thermogenic methane accumulations. Younger seeps in Greenland were associated with zones of ice-sheet retreat since the Little Ice Age. Our findings imply that in a warming climate, disintegration of permafrost, glaciers and parts of the polar ice sheets could facilitate the transient expulsion of 14C-depleted methane trapped by the cryosphere cap.},
	keywords = {Biogeochemistry, Cryospheric science},
	issn = {1752-0894},
	doi = {10.1038/ngeo1480},
	url = {http://www.nature.com/doifinder/10.1038/ngeo1480},
	author = {Walter Anthony, Katey M. and Anthony, Peter and Grosse, Guido and Chanton, Jeffrey}
}
