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1.
Being the heaviest fraction of crude oils, asphaltenes are liable to aggregate, and other molecules in the oils can be steadily adsorbed onto, and even occluded inside the macromolecular structures of the asphaltenes. These occluded compounds inside the asphaltenes can survive over geological time in oil reservoirs owing to effective protection by the macromolecular structures of the asphaltenes. The asphaltenes of a crude oil (ZG31) from the central Tarim Basin, NW China, were hierarchically degraded by increasing the amount of H2O2/CH3COOH to release the occluded compounds. Besides the common components, series of even numbered n-alk-1-enes and 3-ethylalkanes were detected among the occluded compounds. Comparison of the biomarker distributions and the compound-specific C isotopic results between the compounds from the maltenes and those from the occluded fraction, the ZG31 reservoir was suggested to have been charged multiple times, with different charges being derived from different strata of source rocks.  相似文献   
2.
沙丘粒度特征不仅能反映沙丘沙物质的来源与动力,也可以体现地形对风沙流运移的改变。对西藏朋曲流域不同地貌部位流动沙丘表层沉积物的粒度特征进行分析。结果表明:(1)朋曲流域流动沙丘表层沉积物粒度组分以中沙(46.51%)和细沙(40.52%)为主,粗沙(5.87%)与极细沙(5.87%)次之,黏土(0.37%)与粉沙(0.85%)含量最低。流动沙丘表层沉积物平均粒径1.41—2.32 Φ,分选系数0.45—0.79 Φ,偏度0.01—0.24,峰度0.98—1.80。(2)从河漫滩到河流阶地到山坡,流动沙丘粒度逐渐变小,频率分布曲线逐渐变高变窄,粒径越来越集中,沿主导风向自西南向东北概率累积曲线斜率逐渐增大,分选性逐渐变好。(3)河漫滩至河流高级阶地流动沙丘表层沉积物随海拔升高粒径变小,坡麓至坡顶随海拔升高粒径变大,分选却变好,表明山坡上沙丘与阶地上沙丘的沙物质来自于不同河段的河床或河漫滩。  相似文献   
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4.
It is a special petroleum geological phenomenon that Silurian oilsands are extensively distributed in the central and northeast Tarim basin. Some geochemical studies of the oilsands have been carried out, but there is still great controversy over the hydrocarbon-regenerating potential of oilsands and the possibility of Silurian oilsands as hydrocarbon source rocks. In this study, the kinetics of asphaltenes pyrolysis was directly used to simulate the potential of Silurian oilsands for regenerating hydrocarbons. According to the experimental results, combined with other related organic geochemical analysis, it is considered that Silurian oilsands in the Tarim basin have a high hydrocarbon-regenerating potential and are latent hydrocarbon source rocks.  相似文献   
5.
本文通过对南海东北部STD235沉积柱状样品稀土元素(REE)分布模式及特征参数的分析,结合主量元素分析结果,探讨了STD235柱状样沉积物REE指示的物质来源及其纵向变化与环境之间的关系。研究结果表明:20 ka以来STD235站位的沉积物具有基本相同的物质来源,以陆源物质输入为主。通过与周边河流沉积物的对比分析发现,STD235柱状样沉积物REE上地壳标准化的配分模式及其特征参数分布与台湾东南部河流沉积物具有密切的亲缘关系,表明该站位陆源物质主要来源于台湾东南部河流输入,进一步的分析表明台西南河流沉积物对该站位也有所贡献,沉积物的搬运过程主要受到了北太平洋深海流及黑潮的影响。沉积物中REE和主量元素的纵向变化指示20 ka以来南海东北部下陆坡的沉积物源区在冰期时风化作用较弱,间冰期则相对增强。该变化与沉积物源区的气候环境变化有关,指示了20 ka以来台湾地区气候由相对冷干向暖湿转变,由此推测20 ka以来台湾岛和华南地区应该受相同环境因素的制约,东亚季风系统是控制该区域环境变化的主因。此外,在约16~13 ka BP的末次冰消期期间,STD235柱状样沉积物中的各项指标都发生了显著的变化,并都指示了风化作用的逐渐增强,代表了该阶段沉积物源区逐渐向暖湿的气候环境转变。  相似文献   
6.
The crude oils typically from the CambrianLower Ordovician source rocks of Tarim Basin, NW"China, such as TD2 and TZ62S, are13C-enriched with the stable carbon isotopic ratios(VPDB) approaching-28 %.In this paper, the main research viewpoints on this issue are summarized, and combined with results from organic and inorganic carbon isotope stratum curves of the outcrop at the Ya’erdang Mountain in Tarim Basin. In addition, more alternative interpretations are discussed. On one hand, the inverse fractionation features of stable carbon and hydrogen isotopes of these crude oils may imply their protogenous nature. On the other hand, the anisotropy of source rocks and contribution from older stratum source rocks need verifying as well. For the sake of the final resolution of this issue, some further study topics are recommended.  相似文献   
7.
为研究埋地管道在地震激励时管-土相互作用的动力响应问题,研发双向层状剪切连续体模型土箱,建立管G土相互作用有限元分析模型,对横向非一致地震激励下埋地管道地震响应进行数值模拟分析,并与试验结果进行对比.结果表明:数值模拟和振动台试验结果中的管道应变峰值均呈现出沿管道中间大两端小的现象,管道中间应变峰值最小达到两端的1.6倍左右;管道加速度、 土体加速度峰值均随着加载等级的提高而增大,涨幅愈加明显,多峰频率由0~10Hz逐渐向10~ 20Hz频域扩散,管道运动更为自由;土体位移随着加载等级的提高呈现逐级增大的现象,在加载等级增加到0.4g 时位移曲线斜率减小,土体非线性表现明显.数值模拟和振动台试验对比分析的结论表明数值模拟分析的合理性和试验结果的可靠性,为研究横向非一致激励对埋地管道地震响应的影响提供了依据.  相似文献   
8.
The direction of oil charges within a field in the Niger Delta, Nigeria was determined by the sum of differences ranking method of carbazole concentrations after ascertaining other possible geological constraints on their compositional variations. The principle is that the smaller the sum, the closer the well to the source kitchen. The approach makes use of carbazoles’ interaction with the matrix, which leads to a reduction in their concentration with increasing distance from the source kitchen, allowing prediction of the charging direction. A wide range of compositional variations was observed for C1 (806.72–2152.90 μg/g) and C2 (767–2469.72 μg/g) carbazoles within the field. Based on these results, we inferred a filling pathway orientation from west to east. This suggests that the source kitchen—the most promising region for oil exploration—is located in the western part of the oil field.  相似文献   
9.
王泽文 《矿物岩石》1991,11(4):66-73
西藏铬铁矿分布于两个基性超基性岩带上,受板块结合带控制。赋存铬铁矿的岩体无根、与围岩呈断层接触、是板块构造侵位的残体。铬铁矿及赋矿岩石在上地幔形成。成岩成矿机制为地幔岩的局熔改造作用,故属地幔成因。  相似文献   
10.
A series of mass mortalities of the cultured blood clam, Tegillarca granosa, occurred in the Yueqing Bay of China from 2005 to 2009. An obligate intracellular prokaryote, designated as rickettsia-like organism (RLO), was frequently found in the moribund or dead blood clam sample during ultrastructural examination. These organisms were usually round, ellipsoid or occasionally dumbbell-shaped, ranged from approximately 0.28 to 0.71 μm in size and had a trilaminar cell wall. Two reproductive modes of organisms, transverse binary fission and budding, were observed. The organisms were able to form eosinophilic inclusions. Most inclusions were found within epithelial and connective tissues of the mantle, gills and digestive tube. The biological and morphological characteristics indicate that these organisms may belong to the family Rickettsiaceae. RLOs exhibited significant pathogenicity. Cytopathological examinations revealed extensive necrosis and destruction in the infected cell. The degree of tissue destruction was positively related to the number of RLO inclusions in the tissues, and the cytopathological effects were positively related to the number of intracellular RLO. RLOs and their inclusions were discovered throughout different disease areas and in different time periods. The infection intensity of the RLOs was positively correlated with the mortality rate of clams. Therefore, RLO infection might be associated with mass mortalities of cultured blood clams in the Yueqing Bay.  相似文献   
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