Mapping Isotopic and Dissolved Organic Matter Baselines in Waters and Sediments of the Gulf of Mexico
Document Type
Book Chapter
Publication Date
2020
Keywords
Organic carbon, Sediment organic matter Radiocarbon, Dissolved organic matter, Gulf baselines, FTICR-MS, High-resolution mass spectrometry, Ramped pyrolysis
Digital Object Identifier (DOI)
https://doi.org//10.1007/978-3-030-12963-7_10
Abstract
The Deepwater Horizon oil spill released petroleum hydrocarbons that were depleted in δ13C and Δ14C at depth into the Gulf of Mexico. Stable-carbon and radiocarbon isotopic values and high-resolution mass spectrometry were used to follow the distributions of this petroleum and to track its transformation into petrocarbon, a term used to describe crude oil or transformed crude oil following biodegradation, weathering, oxygenation, or loss of lighter components. The term petrocarbon includes oil- or methane-derived carbon assimilated or incorporated into microbial biomass or into the food web as well as degraded and undegraded petroleum constituents. Here we report (1) the increase in the relative abundance of oxygen-containing carbon compounds making up the dissolved organic matter (DOM) with increasing depth through the water column, indicating the biodegradation of DOM as it was transported to depth in the water column, (2) the finding of 14C depletion in DOM indicating petrocarbon inputs, and (3) the decrease and subsequent increase of 14C in the isotopic composition of sinking particles indicating the capture of petrocarbon in sediment traps. In addition, we discuss the 14C depletion of this material once it is sedimented to the seafloor and the implications for oil spill budgets of seafloor petrocarbon deposition.
Was this content written or created while at USF?
Yes
Citation / Publisher Attribution
Mapping Isotopic and Dissolved Organic Matter Baselines in Waters and Sediments of the Gulf of Mexico, in S. A. Murawski, C. H. Ainsworth, S. Gilbert, D. J. Hollander, C. B. Paris, M. Schlüter & D. L. Wetzel (Eds.), Scenarios and Responses to Future Deep Oil Spills: Fighting the Next War, Springer, p. 160-181
Scholar Commons Citation
Chanton, Jeff P.; Jaggi, Aprami; Radović, Jagoš R.; Rosenheim, Brad; Walker, Brett D.; Rogers, Kelsey L.; Bosman, Samantha H.; and Oldenburg, Thomas B. P., "Mapping Isotopic and Dissolved Organic Matter Baselines in Waters and Sediments of the Gulf of Mexico" (2020). C-IMAGE Publications. 155.
https://digitalcommons.usf.edu/cimage_pubs/155
Comments
Data used in this book chapter are available for download.
Radiocarbon measurements on surface sediment organic matter following the Deepwater Horizon Oil Spill, 2010-2012
Isotopic composition of particulates from sediment trap, northern Gulf of Mexico, August 25, 2010 - March 18, 2016
Dissolved inorganic nutrients, pigments, and dissolved oxygen concentrations collected during R/V Pelican cruise July 7-10 2014, northern Gulf of Mexico near DeSoto Canyon, PE15-01
Mass-to-charge ratio (m/z) and monoisotopic intensity from the water samples collected during R/V Justo Sierra and Weatherbird II cruises, JS-0815 and WB-0815, in the Gulf of Mexico from 2015-08-03 to 2015-08-18