Molecular and isotopic signatures of oil-driven bacterial sulfate reduction at seeps in the southern Gulf of Mexico

Krake, Nicola; Birgel, Daniel; Smrzka, Daniel; Zwicker, Jennifer; Huang, Huiwen; Dong, Feng; Bohrmann, Gerhard; Peckmann, Jörn

doi:10.1016/j.chemgeo.2022.120797

Cited by 11 publications

(1 citation statement)

References 154 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A pyrite based proxy offers insights into the evolution of fluid composition at seeps, which is critical because fluid composition governs microbial and metazoan ecology (Orcutt et al, 2010). The significance of distinguishing oilfrom methane-dominated seep systems has gained traction in recent years in the search for end member system identification (Smrzka et al, 2016;Akam et al, 2021;Krake et al, 2022), and reliable proxies are continuously being explored and refined.…”

Section: Introductionmentioning

confidence: 99%

Pyrite-based trace element fingerprints for methane and oil seepage

Smrzka,

Lin,

Monien

et al. 2024

Geochem. Persp. Let.

View full text Add to dashboard Cite

Pyrite forms at marine hydrocarbon seeps as the result of the microbial oxidation of methane, organic matter, and crude oil coupled to sulphate reduction. Redox sensitive and nutrient trace elements in pyrite may hold valuable information on present and past seepage events, the evolution of fluid composition, as well as the presence of heavy hydrocarbon compounds from crude oil. This study uses the trace element compositions of pyrite that formed at methane seeps and crude oil-dominated seeps to constrain element mobilities during the sulphate reduction processes, and examine the degree to which specific trace elements are captured by pyrite. Pyrite forming at oil seeps shows high Mn/Fe ratios and high Mo content compared to pyrite from methane seeps. These patterns suggest either more intense or persistent sulphidic conditions, or an intensified manganese (oxy)hydroxide shuttle process at oil seeps. Copper and Zn are enriched in oil seepagederived pyrite while Ni and V enrichment is less pronounced, suggesting either a selective uptake of specific elements by pyrite, or varying trace element compositions of organic compounds oxidised via microbial reduction.

show abstract

Section: Introductionmentioning

confidence: 99%

Pyrite-based trace element fingerprints for methane and oil seepage

Smrzka,

Lin,

Monien

et al. 2024

Geochem. Persp. Let.

View full text Add to dashboard Cite

show abstract

Biomarker Indicators of Cold Seeps

Guan

Lei

et al. 2023

South China Sea Seeps

View full text Add to dashboard Cite

Lipid biomarkers of seep carbonates and sediments retrieved from the Dongsha area, Shenhu, Site F and Haima in the South China Sea (SCS) over the last two decades were studied. Biomarker inventories, microbial consortia, seepage dynamics, and biogeochemical processes of anaerobic oxidation of methane (AOM), aerobic oxidation of methane (AeOM), and oxidation of non-methane hydrocarbons, were reconstructed. Authigenic carbonates contained varying contents of 13C-depleted archaeal and bacterial biomarkers, reflecting their formation as a result of AOM under varying conditions. Except for the typical isoprenoids found in various cold seeps worldwide, 3,7,11,15-tetramethyl hexadecan-1,3-diol and two novel sn2-/sn3-O-hydroxyphytanyl glycerol monoethers with notable 13C-depletion were observed in authigenic carbonates obtained from Haima, which are most likely hydrolysis products of archaea-specific diethers. Furthermore, molecular fossils, compound-specific δ13C values, and mineralogies, were used to trace dominant microbial consortia, seepage activities, and environmental conditions in the cold seep ecosystems of the SCS. In this chapter, the archaeal and bacterial lipid biomarker geochemistry of methane seeps is systematically introduced. AOM, AeOM, oxidation of non-methane hydrocarbons, oil degradation, and the diagenetic fate of glycerol ethers, are further summarized.

show abstract

Molecular fossils in reefal carbonates and sponges of the deep fore reef of Mayotte and Mohéli, Comoro Islands, western Indian Ocean

Maak,

Birgel,

Reitner

et al. 2023

Facies

View full text Add to dashboard Cite

Microbial carbonates are common components of Quaternary tropical coral reefs. Previous studies revealed that sulfate-reducing bacteria trigger microbial carbonate precipitation in supposedly cryptic reef environments. Here, using petrography, lipid biomarker analysis, and stable isotope data, we aim to understand the formation mechanism of microbial carbonate enclosed in deep fore reef limestones from Mayotte and Mohéli, Comoro Islands, which differ from other reefal microbial carbonates in that they contain less microbial carbonate and are dominated by numerous sponges. To discern sponge-derived lipids from lipids enclosed in microbial carbonate, lipid biomarker inventories of diverse sponges from the Mayotte and Mohéli reef systems were examined. Abundant peloidal, laminated, and clotted textures point to a microbial origin of the authigenic carbonates, which is supported by ample amounts of mono-O-alkyl glycerol monoethers (MAGEs) and terminally branched fatty acids; both groups of compounds are attributed to sulfate-reducing bacteria. Sponges revealed a greater variety of alkyl chains in MAGEs, including new, previously unknown, mid-chain monomethyl- and dimethyl-branched MAGEs, suggesting a diverse community of sulfate reducers different from the sulfate-reducers favoring microbialite formation. Aside from biomarkers specific for sulfate-reducing bacteria, lipids attributed to demosponges (i.e., demospongic acids) are also present in some of the sponges and the reefal carbonates. Fatty acids attributed to demosponges show a higher diversity and a higher proportion in microbial carbonate compared to sponge tissue. Such pattern reflects significant taphonomic bias associated with the preservation of demospongic acids, with preservation apparently favored by carbonate authigenesis.

show abstract

Molecular and isotopic signatures of oil-driven bacterial sulfate reduction at seeps in the southern Gulf of Mexico

Cited by 11 publications

References 154 publications

Pyrite-based trace element fingerprints for methane and oil seepage

Pyrite-based trace element fingerprints for methane and oil seepage

Biomarker Indicators of Cold Seeps

Molecular fossils in reefal carbonates and sponges of the deep fore reef of Mayotte and Mohéli, Comoro Islands, western Indian Ocean

Contact Info

Product

Resources

About