1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recogni...1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recognition of"bioherms,"algal layers,and mats covering hundreds of square km of lake area,these features have not been the展开更多
以青藏高原极端盐湖为研究对象,采用16S r RNA基因(V3~V4区)高通量测序方法分析盐湖细菌的群落结构差异和超盐环境因子的制约相关性.结果显示,超盐环境样本中细菌的群落结构组成相对稳定,进化趋同,且复杂度和多样性指数显著低于非超盐环...以青藏高原极端盐湖为研究对象,采用16S r RNA基因(V3~V4区)高通量测序方法分析盐湖细菌的群落结构差异和超盐环境因子的制约相关性.结果显示,超盐环境样本中细菌的群落结构组成相对稳定,进化趋同,且复杂度和多样性指数显著低于非超盐环境.青藏高原超盐环境中细菌的优势类群是厚壁菌门Firmicutes(74.04%~81.04%)、次为变形菌门Proteobacteria(15.51%~20.06%)、拟杆菌门Bacteroidetes(2.68%~4.84%)和放线菌门Actinobacteria(0.71%~2.45%).比较分析其它类型超盐环境,青藏高原超盐环境具有高丰度的特色属群芽孢杆菌属Bacillus(50.63%~58.35%)、乳球杆菌属Lactococcus(9.28%~11.81%)和海洋芽孢杆菌属Oceanobacillus(8.41%~10.52%).基于典范对应CCA分析,表明优势属群(Bacillus、Lactococcus、Pseudomonas、Oceanobacillus、Stenotrophomonas、Psychrobacter、Myroides、Brochothrix和Arthrobacter)和超盐样本的聚集,与环境因子(总盐度、Cl^-、K^+、Mg^(2+)和CO_3^(2-)浓度)呈明显的正相关.展开更多
The distribution,the relative composition,and their variation of methylated chromans(MTTC) with maturation of organic matter in the source rocks from Mingjia 1 well,Jianghan hypersaline basin,have been analyzed and st...The distribution,the relative composition,and their variation of methylated chromans(MTTC) with maturation of organic matter in the source rocks from Mingjia 1 well,Jianghan hypersaline basin,have been analyzed and studied. There is a close relationship between the distribution of methylatd chromans and paleosalinity of depositional environment. In the Eq1-Eq3 source rocks deposited under hypersaline environment with lower Pr/Ph ratio,higher gammacerane index and abundant organic sulfur-containing compounds,methyl MTTC and dimethyl MTTC are main components,but in the Eq4 source rocks deposited non-hypersaline environment with relatively higher Pr/Ph ratio,lower gammacerane index and organic sulfur-containing compounds,trimethyl MTTC is a major compound in methylate chromans. Obviously,the distributions and the compositions of methylated chromans in the source rocks are in harmony with biomarker indicators indicating the paleaosalinity and redox of depositional environment. The relationship between the ratio of 5,8-dimethyl MTTC to 7,8-dimethyl MTTC(dimethyl MTTC ratio) and the maturity of organic matter in the source rocks from Mingjia 1 well has been discussed. The results show that dimethyl MTTC ratio increased with the burial depth and the maturation of organic matter in the source rocks,especially in immature level. It is noteworthy that this ratio is very susceptible to small variation in the maturity of organic matter in the source rocks when vitrinite reflectance Ro is less than 0.65%. It may imply that this ratio is a good and susceptible aromatic maturity indicator for the relative maturity of organic matter in immature source rocks.展开更多
Crude oils from different basins in China, Anstralia and New Zealand were analyzed to character-ize aromatic hydrocarbons produced in different environments by means of GC/MS.The distributions of some conunon compound...Crude oils from different basins in China, Anstralia and New Zealand were analyzed to character-ize aromatic hydrocarbons produced in different environments by means of GC/MS.The distributions of some conunon compounds such as naphthalene, phenanthrene, chrysene, pyrene, fluoranthene,fluorene, dibenzothiophene and dibenzofuran were found to be related to sedimentary environments.Especially the relative contents of fluorenes, dibenzofurans and dibenzothiophenes can be used to di-vide the oils into three types: (1) saline or marine carbonate environment; (2) fresh -brackish water lake; (3 ) swamp and coal-bearing sequence.Aromahc biomarkers (e.g. retene, nor-abietene, derivatives of lupeol and β-amyrin) represent higher plant inputs with respect to the precursors of crude oils. High contents of sulphur-containing compounds like benzothiophene and dibenzothiophene series indicate a reducing sulphur-abundant diagenehc condition. The benzohopane series (C32-C35) was identified both in hypersaline and coal-bearing basins, and it is postulated to be the result of strong bacteria achvity. In all the sam-ples, a complete series of alkyl benzenes was analyzed. The similarity of its carbon-number distribu-tion with that of n-alkanes probably suggests their genetic relationship.The distribution of the methylphenanthrene series reflects the evolution degree of crude oils, MPI holding a positive correlation with C29 -sterane 20S/(20S+ 20R).展开更多
Some 11 novel series of biological markers, aryl isoprenoids, have been found in Sunniland sedimentary organic matter (both oil and its source rock) of the South Florida Basin (USA). All of them have the same homologo...Some 11 novel series of biological markers, aryl isoprenoids, have been found in Sunniland sedimentary organic matter (both oil and its source rock) of the South Florida Basin (USA). All of them have the same homologous key ions m/z 91+14n (n=0—10). In this paper, only one of these homologous series, 2, 3, 6-trimethylphenylisoprenoids, will be discussed organic-geochemically. Two new maturity indicators, ΣHⅠ/ΣHⅡ and ΣHB/ΣHA, have been put forward, and it is suggested that these novel biomarker compounds can be used as indicators of organic facies and maturity of sedimentary organic matter.展开更多
文摘1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recognition of"bioherms,"algal layers,and mats covering hundreds of square km of lake area,these features have not been the
文摘以青藏高原极端盐湖为研究对象,采用16S r RNA基因(V3~V4区)高通量测序方法分析盐湖细菌的群落结构差异和超盐环境因子的制约相关性.结果显示,超盐环境样本中细菌的群落结构组成相对稳定,进化趋同,且复杂度和多样性指数显著低于非超盐环境.青藏高原超盐环境中细菌的优势类群是厚壁菌门Firmicutes(74.04%~81.04%)、次为变形菌门Proteobacteria(15.51%~20.06%)、拟杆菌门Bacteroidetes(2.68%~4.84%)和放线菌门Actinobacteria(0.71%~2.45%).比较分析其它类型超盐环境,青藏高原超盐环境具有高丰度的特色属群芽孢杆菌属Bacillus(50.63%~58.35%)、乳球杆菌属Lactococcus(9.28%~11.81%)和海洋芽孢杆菌属Oceanobacillus(8.41%~10.52%).基于典范对应CCA分析,表明优势属群(Bacillus、Lactococcus、Pseudomonas、Oceanobacillus、Stenotrophomonas、Psychrobacter、Myroides、Brochothrix和Arthrobacter)和超盐样本的聚集,与环境因子(总盐度、Cl^-、K^+、Mg^(2+)和CO_3^(2-)浓度)呈明显的正相关.
基金Supported by Key Technologies R & D Programme (Grant No. 2004BA616A02-04-02-01)
文摘The distribution,the relative composition,and their variation of methylated chromans(MTTC) with maturation of organic matter in the source rocks from Mingjia 1 well,Jianghan hypersaline basin,have been analyzed and studied. There is a close relationship between the distribution of methylatd chromans and paleosalinity of depositional environment. In the Eq1-Eq3 source rocks deposited under hypersaline environment with lower Pr/Ph ratio,higher gammacerane index and abundant organic sulfur-containing compounds,methyl MTTC and dimethyl MTTC are main components,but in the Eq4 source rocks deposited non-hypersaline environment with relatively higher Pr/Ph ratio,lower gammacerane index and organic sulfur-containing compounds,trimethyl MTTC is a major compound in methylate chromans. Obviously,the distributions and the compositions of methylated chromans in the source rocks are in harmony with biomarker indicators indicating the paleaosalinity and redox of depositional environment. The relationship between the ratio of 5,8-dimethyl MTTC to 7,8-dimethyl MTTC(dimethyl MTTC ratio) and the maturity of organic matter in the source rocks from Mingjia 1 well has been discussed. The results show that dimethyl MTTC ratio increased with the burial depth and the maturation of organic matter in the source rocks,especially in immature level. It is noteworthy that this ratio is very susceptible to small variation in the maturity of organic matter in the source rocks when vitrinite reflectance Ro is less than 0.65%. It may imply that this ratio is a good and susceptible aromatic maturity indicator for the relative maturity of organic matter in immature source rocks.
文摘Crude oils from different basins in China, Anstralia and New Zealand were analyzed to character-ize aromatic hydrocarbons produced in different environments by means of GC/MS.The distributions of some conunon compounds such as naphthalene, phenanthrene, chrysene, pyrene, fluoranthene,fluorene, dibenzothiophene and dibenzofuran were found to be related to sedimentary environments.Especially the relative contents of fluorenes, dibenzofurans and dibenzothiophenes can be used to di-vide the oils into three types: (1) saline or marine carbonate environment; (2) fresh -brackish water lake; (3 ) swamp and coal-bearing sequence.Aromahc biomarkers (e.g. retene, nor-abietene, derivatives of lupeol and β-amyrin) represent higher plant inputs with respect to the precursors of crude oils. High contents of sulphur-containing compounds like benzothiophene and dibenzothiophene series indicate a reducing sulphur-abundant diagenehc condition. The benzohopane series (C32-C35) was identified both in hypersaline and coal-bearing basins, and it is postulated to be the result of strong bacteria achvity. In all the sam-ples, a complete series of alkyl benzenes was analyzed. The similarity of its carbon-number distribu-tion with that of n-alkanes probably suggests their genetic relationship.The distribution of the methylphenanthrene series reflects the evolution degree of crude oils, MPI holding a positive correlation with C29 -sterane 20S/(20S+ 20R).
文摘Some 11 novel series of biological markers, aryl isoprenoids, have been found in Sunniland sedimentary organic matter (both oil and its source rock) of the South Florida Basin (USA). All of them have the same homologous key ions m/z 91+14n (n=0—10). In this paper, only one of these homologous series, 2, 3, 6-trimethylphenylisoprenoids, will be discussed organic-geochemically. Two new maturity indicators, ΣHⅠ/ΣHⅡ and ΣHB/ΣHA, have been put forward, and it is suggested that these novel biomarker compounds can be used as indicators of organic facies and maturity of sedimentary organic matter.
