کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5161525 1502277 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Predominance of archaea-derived hydrocarbons in an Early Triassic microbialite
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Predominance of archaea-derived hydrocarbons in an Early Triassic microbialite
چکیده انگلیسی
We investigated the distribution of lipids in Lower Triassic sedimentary rocks (252-247 myr) from South China, including a shallow water microbialite in the uppermost section of the outcrop. Archaeal derived hydrocarbons were the major constituents of the microbialite from the latest Early Triassic. Among these, we detected (i) abundant C40 acyclic and monocyclic biphytanes (possibly derived from glycerol dialkyl glycerol tetraether lipids) and their degradation products, C30-39 pseudohomologues and (ii) a C25 head-to-tail linked (regular) isoprenoid hydrocarbon [possibly derived from dialkyl glycerol diether lipids (DGDs)] and its degradation products, C21-24 pseudohomologues and abundant pristane and phytane. Through combination of compound-specific stable carbon isotope analysis of isoprenoid hydrocarbons, which had average δ13C values of −35‰ to −30‰, and their molecular distribution, it was not possible to unambiguously define the archaeal source for the biphytanes in the microbialite. The δ13C values for pristane and phytane were similar to those for head-to-tail linked C21-25 isoprenoids; potential source organisms for these compounds were halophilic archaea. Except for methane seep microbialites, no other ancient or recent phototrophic microbialites have been reported to contain predominantly archaeal isoprenoid hydrocarbons. Our findings suggest the presence of a new type of microbialite.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Organic Geochemistry - Volume 85, August 2015, Pages 66-75
نویسندگان
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