Thirty-five different samples from three different sulfur cycles were examined in this stratigraphically oriented study of the Shell 22x-l well (U.S.G.S. C177 core) in the Piceance Basin, Colorado. Carbon isotopic compositions of constituents of Green River bitumens indicate mixing of three main components: products of primary photoautotrophs and their immediate consumers (delta approximately -30% vs PDB), products of methanotrophic bacteria (delta approximately -85%), and products of unknown bacteria (delta approximately -40%). For individual compounds synthesized by primary producers, delta-values ranged from -28 to -32%. 13C contents of individual primary products (beta-carotane, steranes, acyclic isoprenoids, tricyclic triterpenoids) were not closely correlated, suggesting diverse origins for these materials. 13C contents of numerous hopanoids were inversely related to sulfur abundance, indicating that they derived both from methanotrophs and from other bacteria, with abundances of methanotrophs depressed when sulfur was plentiful in the paleoenvironment. gamma-Cerane coeluted with 3 beta(CH3),17 alpha(H),21 beta(H)-hopane, but delta-values could be determined after deconvolution. gamma-Cerane (delta approximately -25%) probably derives from a eukaryotic heterotroph grazing on primary materials, the latter compound (delta approximately -90%) must derive from methanotrophic organisms. 13C contents of n-alkanes in bitumen differed markedly from those of paraffins generated pyrolytically. Isotopic and quantitative relationships suggest that alkanes released by pyrolysis derived from a resistant biopolymer of eukaryotic origin and that this was a dominant constituent of total organic carbon.

中文翻译：

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绿河油页岩同位素生物地球化学研究

在这项针对位于科罗拉多州 Piceance 盆地的 Shell 22x-l 井（USGS C177 岩心）的地层定向研究中，检查了来自三个不同硫循环的 35 个不同样品。Green River 沥青成分的碳同位素组成表明三种主要成分的混合：初级光合自养生物及其直接消费者的产物（delta 大约 -30% vs PDB）、甲烷营养细菌的产品（delta 大约 -85%）和未知的产品细菌（增量约为 -40%）。对于初级生产者合成的单个化合物，δ 值范围从 -28% 到 -32%。单个初级产品（β-胡萝卜素、甾烷、无环类异戊二烯、三环三萜）的 13C 含量没有密切相关，表明这些材料的来源不同。许多hopanoids的13C含量与硫丰度呈负相关，表明它们来自甲烷氧化菌和其他细菌，当古环境中硫含量丰富时，甲烷氧化菌的丰度降低。γ-Cerane 与 3 beta(CH3),17 alpha(H),21 beta(H)-hopane 共流出，但可以在解卷积后确定 delta 值。γ-Cerane (delta 大约 -25%) 可能来自以主要材料为食的真核异养生物，后者化合物 (delta 大约 -90%) 必须来自甲烷营养生物。沥青中正构烷烃的 13C 含量与热解产生的石蜡明显不同。