Organic lipids with different occurrence modes in a sedimentary core in a subtropicalfreshwater lake, Gucheng Lake, were sequentially extracted, separated and analyzed. Thedown-core variations of OEP index of alkanes,...Organic lipids with different occurrence modes in a sedimentary core in a subtropicalfreshwater lake, Gucheng Lake, were sequentially extracted, separated and analyzed. Thedown-core variations of OEP index of alkanes, C<sub>18:2</sub>/C<sub>18:0</sub> ratios of fatty acids, ratios of boundfatty acids to free fatty acids, thermo-maturity indices of hopanoid hydrocarbons and relativeconcentrations of sedimentary minerals revealed an evident increasing in allochthonous inputfrom rock detritus below 12.28 m in the sedimentary profile. The distribution pattern of tightly-bound β-hydroxy fatty acids indicated a difference in bacterial communities above and below theboundary, as well as the gammacerane index may assign a significant change in lake watersalinity. The evidence, in general, suggested that a significant paleoenvironmental change hadtaken place in ca. 9.6 kaBP on the regional basis.展开更多
METAL minerals precipitate generally from ore-forming fluid. It is suggested that organic mat-ter in ore-forming fluid is one of the best media which show the role of organic matter in oregenesis. Because mineralizing...METAL minerals precipitate generally from ore-forming fluid. It is suggested that organic mat-ter in ore-forming fluid is one of the best media which show the role of organic matter in oregenesis. Because mineralizing temperatures of many ore deposits exceeded the stable rangesof liquid hydrocarbons, only light hydrocarbons were preserved well in inclusions. Thus,展开更多
THE previous simulating experiments show that many algae can greatly accumulate goldfrom solution under some conditions. Some other experiments further indicate that organ-ic matter and crude oil can also play an impo...THE previous simulating experiments show that many algae can greatly accumulate goldfrom solution under some conditions. Some other experiments further indicate that organ-ic matter and crude oil can also play an important role in gold geochemistry processes such asleaching, migration, reduction and precipitation. However, these biometallogeneses are展开更多
MOST previous studies of organic geochemistry in an ore deposit focus on the bitumen and kero-gen associated with ores and host rocks, not on that of fluid inclusions. However, organicmatter only in ore-forming fluids...MOST previous studies of organic geochemistry in an ore deposit focus on the bitumen and kero-gen associated with ores and host rocks, not on that of fluid inclusions. However, organicmatter only in ore-forming fluids is directly involved in metallogenesis. In this note, a series ofbiomarkers in hydrocarbon inclusions were identified through gas chromatography-mass spec-trometry (GC-MS). Comparison and contrast on extractable organic matter (EOM) was madeamong inclusions, ores and host rocks. Metallogenesis related to EOM was also discussed.展开更多
m-QUARTERPHENYL, also nominated as 5′-phenyl-1, 1′: 3′1″-terphenyl, is one of the four-ringpolycyclic aromatic hydrocarbons （PAHs） with its four rings meta-linked together with C—Cbonds. Its molecular formula i...m-QUARTERPHENYL, also nominated as 5′-phenyl-1, 1′: 3′1″-terphenyl, is one of the four-ringpolycyclic aromatic hydrocarbons （PAHs） with its four rings meta-linked together with C—Cbonds. Its molecular formula is C<sub>18</sub>H<sub>24</sub> and its molecular weight 306. m-Quarterphenyl and other kinds of quarterphenyls as well as terphenyls have been de-tected in aerosols by Beemaert by use of GC-MS. Tong, and Karasek and Tong ana-展开更多
文摘Organic lipids with different occurrence modes in a sedimentary core in a subtropicalfreshwater lake, Gucheng Lake, were sequentially extracted, separated and analyzed. Thedown-core variations of OEP index of alkanes, C<sub>18:2</sub>/C<sub>18:0</sub> ratios of fatty acids, ratios of boundfatty acids to free fatty acids, thermo-maturity indices of hopanoid hydrocarbons and relativeconcentrations of sedimentary minerals revealed an evident increasing in allochthonous inputfrom rock detritus below 12.28 m in the sedimentary profile. The distribution pattern of tightly-bound β-hydroxy fatty acids indicated a difference in bacterial communities above and below theboundary, as well as the gammacerane index may assign a significant change in lake watersalinity. The evidence, in general, suggested that a significant paleoenvironmental change hadtaken place in ca. 9.6 kaBP on the regional basis.
文摘METAL minerals precipitate generally from ore-forming fluid. It is suggested that organic mat-ter in ore-forming fluid is one of the best media which show the role of organic matter in oregenesis. Because mineralizing temperatures of many ore deposits exceeded the stable rangesof liquid hydrocarbons, only light hydrocarbons were preserved well in inclusions. Thus,
文摘THE previous simulating experiments show that many algae can greatly accumulate goldfrom solution under some conditions. Some other experiments further indicate that organ-ic matter and crude oil can also play an important role in gold geochemistry processes such asleaching, migration, reduction and precipitation. However, these biometallogeneses are
文摘MOST previous studies of organic geochemistry in an ore deposit focus on the bitumen and kero-gen associated with ores and host rocks, not on that of fluid inclusions. However, organicmatter only in ore-forming fluids is directly involved in metallogenesis. In this note, a series ofbiomarkers in hydrocarbon inclusions were identified through gas chromatography-mass spec-trometry (GC-MS). Comparison and contrast on extractable organic matter (EOM) was madeamong inclusions, ores and host rocks. Metallogenesis related to EOM was also discussed.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 49375249).
文摘m-QUARTERPHENYL, also nominated as 5′-phenyl-1, 1′: 3′1″-terphenyl, is one of the four-ringpolycyclic aromatic hydrocarbons （PAHs） with its four rings meta-linked together with C—Cbonds. Its molecular formula is C<sub>18</sub>H<sub>24</sub> and its molecular weight 306. m-Quarterphenyl and other kinds of quarterphenyls as well as terphenyls have been de-tected in aerosols by Beemaert by use of GC-MS. Tong, and Karasek and Tong ana-
