Fatty acids were extracted from fluid inclusions, and analyzed for distribution and individual 613C values to determine if there exists sulfate-reducing bacteria (SRB) and what substrates SRB depleted during U miner...Fatty acids were extracted from fluid inclusions, and analyzed for distribution and individual 613C values to determine if there exists sulfate-reducing bacteria (SRB) and what substrates SRB depleted during U mineralization in the Dongsheng deposit. The 10-methylhexadecanoic acid (10Mel6:0) has been detected from most of the samples using GC-MS based on relative retention time and co-injection of standard 10Me16:0 compound. Samples with higher 10Me16: 0 concentrations, show higher U contents. The presence of 10Mel6:0 along with iso-ω7-cis-heptadecenoic acid (i17:1ω7c) and ω7-cisoctadecenoic acid (18:1ω7c) in the fluid inclusions may indicate the occurrence of SRB during the U mineralization. Saturated fatty-acids and unsaturated fatty-acids detected in this study have individual δ^13C values from-30.3‰ to-28.5‰ and-30.5‰ to-27.9‰, respectively. These values are close to those of n-alkanes of the associated oils and the bulk oils, but significantly distinct from methane, thus the oils are concluded to have been used as substrate for the microorganisms to survive on. This proposal is supported by oil biodegradation and ore-stage calcite cement with δ^13C values from-1.4‰ to-17.2‰.展开更多
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KZCX2-YW-JC102)the National Basic Research Program of China(No.2011CB808800)the China National Funds for Distinguished Young Scientists(No.41125009)
文摘Fatty acids were extracted from fluid inclusions, and analyzed for distribution and individual 613C values to determine if there exists sulfate-reducing bacteria (SRB) and what substrates SRB depleted during U mineralization in the Dongsheng deposit. The 10-methylhexadecanoic acid (10Mel6:0) has been detected from most of the samples using GC-MS based on relative retention time and co-injection of standard 10Me16:0 compound. Samples with higher 10Me16: 0 concentrations, show higher U contents. The presence of 10Mel6:0 along with iso-ω7-cis-heptadecenoic acid (i17:1ω7c) and ω7-cisoctadecenoic acid (18:1ω7c) in the fluid inclusions may indicate the occurrence of SRB during the U mineralization. Saturated fatty-acids and unsaturated fatty-acids detected in this study have individual δ^13C values from-30.3‰ to-28.5‰ and-30.5‰ to-27.9‰, respectively. These values are close to those of n-alkanes of the associated oils and the bulk oils, but significantly distinct from methane, thus the oils are concluded to have been used as substrate for the microorganisms to survive on. This proposal is supported by oil biodegradation and ore-stage calcite cement with δ^13C values from-1.4‰ to-17.2‰.