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31.
应用含氮化合物探讨新疆轮南油田油气运移   总被引:26,自引:2,他引:26  
新疆轮南地区原油中含有丰富的吡咯类含氮化合物,不同层系或相同层系原油中吡咯类化合物总体分布型式相似,但绝对丰富与相对颁布差异明显,显示显著的油气运移分馏效应。分析结果表明,奥陶系原油与三叠系、侏罗系原油具不同成藏期次与油气运移方向,奥陶系、石炭系原油运移方向为自西而东,主要注入点在轮南、桑塔木断垒带的西南侧;三叠系、株罗系原油主要通过断层运移、聚集成藏,在后期构造演化过程中发生侧向分配调整。吡咯类  相似文献   
32.
A large number of disinfectants and insecticides were used on a large scale after the Wenchuan 5.12 Violent Earthquake. The disinfectants and insecticides, including HCH (hexachlorocyclohexane) and DDT (dichlorodiphenyltrichoroethane) as representative OCPs, could lead to serious environmental problems. In order to disclose the residues of HCH and DDT in soils following the Wenchuan 5.12 Violent Earthquake, surface soils in Dujiangyan City and Beichuan County were sampled in 2009. The samples were analyzed by GC/MS after pre- treatment by ultrasonic solvent extraction. It has been found that the concentra-tions of γ-HCH, β-HCH and 4,4’-DDT in soils of Beichuan County were 94–102.4, 14.1–36.1 and 2.9–4.3 times high their concentrations in those of the Wolong Nature Reserve, and the concentrations in soils of Dujiangyan City were 52.4–61.6, 8.8 –45.3 and 5.4–6.2 times high their concentrations in soils of the Wolong Nature Reserve, respectively. According to the isomers of HCHs and metabolites of DDTs, it could be concluded that these areas may have additional inputs of lindane and 4,4’-DDT.  相似文献   
33.
Devonian cutinitic liptobiolith is a special cuticle-rich coal formed during the early stage of land plant evolution. In China, this special coal has previously only been reported in the Yangtze area, with the Luquan Devonian cutinitic liptobiolith of Yunnan Province being the most well-known. Recently, this type of coal was first discovered in the Bulonggoer Sag, to the northwest of the Junggar Basin, NW Xinjiang. Its geological age is regarded as the Givetian period of the late Middle Devonian,which is equivalent to the age of the Luquan Devonian coal. The cutinitic liptobiolith from NW Xinjiang has a distinct sheet-like texture resembling a stack of paper or leaf sheets in appearance, and so it is commonly called "paper coal" or "leaf coal". Ribbonlike cutinite(thick-walled type) is the most abundant maceral in the coal(>60% and up to 80%, on a mineral-free basis), followed by ribbon-like collotelinite. The NW Xinjiang and Luquan cutinitic liptobioliths share similar maceral compositions;while their coal-forming plants and depositional conditions are distinct. The NW Xinjiang cutinitic liptobiolith was deposited in a regional fluvial or flood plain condition, with lycopsids as the dominant coal-forming plants. In contrast, the Luquan cutinitic liptobiolith formed in a coastal-lagoon environment, with primitive ferns as the predominant coal-forming plants, followed by lycopsids. The saturated fractions of the NW Xinjiang and Luquan liptobioliths are mainly composed of tetracyclic diterpanes. However, the tetracyclic diterpane compositions in the NW Xinjiang cutinitic liptobiolith are distinct from those in the Luquan Devonian coal:The former is dominated by atisanes and the latter is mainly composed of phyllocladanes. Different coal-forming plants may have contributed to the distinct tetracyclic diterpane compositions.  相似文献   
34.
苏北黄桥地区东吴运动热事件的有机地球化学证据   总被引:4,自引:0,他引:4  
王铁冠  包建平 《地质学报》1998,72(4):358-366
地质事件是地球上短期内突发的非生物变化或事变,岩浆活动可导致地史中的热事件。本文首次采用多项有机地球化学的分析测试技术,通过对下扬子盆地黄桥地区一口石油探井的系统研究,借助于烃源岩的光学(镜质组反射率Ro、孢粉颜色指数SCI)、热学(热解峰温tmax)和化学(氢指数IH、降解潜率D以及H/C和O/C原子比)等特征的异常变化,确认发生在早二叠世末期的东吴运动热事件的存在,岩浆浅成-超浅成侵入或喷发活  相似文献   
35.
Some Ordovician and Triassic oils in Block 9 are characterized by light oils,which have distinctly differentiated from heavy oils in other blocks in the Tahe Oilfield,Tarim Basin.Based on the whole oil gas chroma- tograms,this paper estimates the effect of oil migration and fractionation and the amount of depletion(Q)in terms of the n-alkanes depletion model.The results showed that the amount of depletion in the Ordovician reservoir is highest in the east of this block,e.g.the depletion is 97% in Well T904.The amount of Q gets lower to the west,e.g.the depletion is 53.4%in Well T115 and there is no sign of depletion in Well S69.It is suggested that the direction of gas washing is from the east to the west.The compositions and isotopic characteristics of associated gas in Ordovician oils indicated that the gas might be derived from Cambrian source rocks of the Caohu Depression which lies to the east of Block 9.In contrast,no obvious depletion of n-alkanes in Triassic oils was found,suggesting that the migration pathway of natural gas has been limited to the Ordovician karst fracture system formed in the Early Hercynian Orogeny.Different depletions of the Ordovician and Triassic oils can reveal fault activities in this region.  相似文献   
36.
Biomarkers, or the so-called molecular fossils, are used tentatively in the Eogene lacustrine stratigraphy study in the Jiyang Sub-basin. Notwithstanding the fact that unidentified microfossils or amorphism and acritarchae are widely distributed in lacustrine source rocks, molecular fossils are useful to identify the sources. It is helpful to reconstruct the palaeo-enviroment, palaeo-ecosystem and compartmentalize the stratigraphic sequence by using molecular fossils with which the existence and types of microbes including bacteria, archaea and certain algae can be identified.  相似文献   
37.
How to quantitatively evaluate the maturity of crude oils is still an open question. Mango discovered a remarkable compositional invariance of four isoheptane ratios in crude oils, and proposed a steady-state catalytic model for the origin of light hydrocarbons. According to this model, 2,4/2,3 dimethylpentane ratio is a pure temperature parameter. Bement, Mango et al. established the functional equation between the two parameters--light hydrocarbon temperature and burial temperature and applied it to the calculation of hydrocarbon-generating temperature, which provided a new choice for the study of oil maturity. In this paper, the Mango's parameters for hydrocarbons from the Tazhong area were calculated, the average K1 value is 1.06, which is in good consistency with the Mango's proposal that the K1 value is relatively stable. Calculated with the functional formula of hydrocarbon-generating temperature, the hydrocarbon-generating temperatures are with the range of 120-129℃, and the converted vitrinite reflectance (Ro) varies from 0.88% to 0.90%. This is well consistent with the maturity characteristics of neohopanes. The results have verified the reliability of this method.  相似文献   
38.
洪泽凹陷低熟原油的饱和烃化合物组合   总被引:5,自引:0,他引:5  
通过对洪泽凹陷低熟原油中饱和烃化合物组合研究表明,它们能够较为有效和准确定低熟原油的生烃母质和沉积环境。在洪泽凹陷原油中,存在着着典型半咸水-咸水环境的生物标志物组合,如Pr/Ph〈1,丰富的伽玛蜡烷,相对较高含量的C294-甲基甾烷,C26甾烷,甲藻甾烷等。  相似文献   
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