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1.
Molecular biomarkers are the important maturity parameters for sedimentary organic matter.They have also been widely used for determining the maturity of organic matter in ore deposits. However,during the study of organic matter in the Kupferschiefer from the Lubin mine, it had been found that the biomarkers were influenced by sulfide formation. In order to probe into the degree of influence on biomarkers, seven samples collected from a Kupferschiefer section from the Lubin mine were analyzed by various geochemical methods. The results indicated that in the samples with higher copper contents, the values of biomarkers are lower than in the samples with lower copper contents. In highly mineralized samples, hydrogen donation for thermochemical sulfate reduction (TSR) occurred in alkylated phenanthrenes and naphthalenes, leading to the decrease of 12 biomarker parameters during the Kupferschiefer mineralization.  相似文献   

2.
Natural gas exploration in Nanpu sag, Bohai Bay Basin, has achieved breakthroughs in recent years, and a number of natural gas and condensate wells with high yield have been found in several structures in the beach area. Daily gas production of single wells is up to 170,000 m3, and high-yield wells are mainly distributed in?the Nanpu No. 1 structural belt.?Studies have shown that these natural gases are mainly hydrocarbon gases, with methane content about 80% to 90% and ethane 6%-9%, so they are mainly wet gas; and non-hydrocarbons are at a low level.?Carbon isotopes of methane range from -42‰ to -36‰, and ethane from -28‰ to -26‰. Calculated maturity based on the relationship between δ13C and Ro of natural gas, the gases are equivalent to those generated from organic matter when Ro is 1.0%-1.7% (mainly 1.25%-1.32%). The natural gas is oil-type gas generated from the source rocks at mature to high mature stage, associated with condensate, so carbon isotopes of the gases are heavier. Natural gas in the Nanpu No.1 structural belt is mainly associated gas with condensate. The analysis of the origin and source of natural gas and condensate, combined with the monomer hydrocarbon carbon isotopes and biomarker, indicated that the main source rocks in the Nanpu No.1 structural belt were Es3 (the lower member of the Shahejie Formation), followed by Es1 (the upper member of the Shahejie Formation).?The high-mature hydrocarbons from source rocks in the deep sag mainly migrated through deep inherited faults into shallow traps and accumulated to form oil and gas pools. Therefore, there is a great potential for exploring gas in deep layers.  相似文献   

3.
The typical characteristics of shale gas and the enrichment differences show that some shale gases are insufficiently explained by the existing continuous enrichment mode. These shale gases include the Wufeng–Longmaxi shale gas in the Jiaoshiba and Youyang Blocks, the Lewis shale gas in the San Juan Basin. Further analysis reveals three static subsystems (hydrocarbon source rock, gas reservoirs and seal formations) and four dynamic subsystems (tectonic evolution, sedimentary sequence, diagenetic evolution and hydrocarbon-generation history) in shale- gas enrichment systems. Tectonic evolution drives the dynamic operation of the whole shale-gas enrichment system. The shale-gas enrichment modes controlled by tectonic evolution are classifiable into three groups and six subgroups. Group I modes are characterized by tectonically controlled hydrocarbon source rock, and include continuous in-situ biogenic shale gas (I1) and continuous in-situ thermogenic shale gas (I2). Group II modes are characterized by tectonically controlled gas reservoirs, and include anticline-controlled reservoir enrichment (II1) and fracture-controlled reservoir enrichment (II2). Group III modes possess tectonically controlled seal formations, and include faulted leakage enrichment (III1) and eroded residual enrichment (III2). In terms of quantity and exploitation potential, I1 and I2 are the best shale-gas enrichment modes, followed by II1 and II2. The least effective modes are III1 and III2. The categorization provides a different perspective for deep shale-gas exploration.  相似文献   

4.
Forty-six crude oil samples were selected from the Ordovician in the northwestern part of the Tahe oilfield for detailed molecular geochemical and isotopic analysis, including group compositions, carbonhydrogen isotopes and gas chroma-tograms of saturated hydrocarbons, as well as the characteristics of terpane, sterane and other biomarkers, indicating that crude oils are of the same origin from different districts in the Tahe oilfield and were derived from the same source kitchen (or oil source formation), i.e., mainly stemming from marine hydrocarbons. Detailed studies of oil physical properties of 25-honpane revealed that such oils have heavy or thick oil qualities due to biodegradation. Comprehensive assessment in terms of five maturity parameters shows that the oils from the Ordovician with Ro values varying from 0.80% to 1.59% are widely distributed in the northwest of the Tahe oilfield.  相似文献   

5.
A scientific exploration well(CK1) was drilled to expand the oil/gas production in the western Sichuan depression, SW, China. Seventy-three core samples and four natural gas samples from the Middle–Late Triassic strata were analyzed to determine the paleo-depositional setting and the abundance of organic matter(OM) and to evaluate the hydrocarbon-generation process and potential. This information was then used to identify the origin of the natural gas. The OM is characterized by medium n-alkanes(n C_(15)–n C_(19)), low pristane/phytane and terrigenous aquatic ratios(TAR), a carbon preference index(CPI) of ～1, regular steranes with C_(29) C_(27) C_(28), gammacerane/C_(30) hopane ratios of 0.15–0.32, and δD_(org) of-132‰ to-58‰, suggesting a marine algal/phytoplankton source with terrestrial input deposited in a reducing–transitional saline/marine sedimentary environment. Based on the TOC, HI index, and chloroform bitumen "A" the algalrich dolomites of the Leikoupo Formation are fair–good source rocks; the grey limestones of the Maantang Formation are fair source rocks; and the shales of the Xiaotangzi Formation are moderately good source rocks. In addition, maceral and carbon isotopes indicate that the kerogen of the Leikoupo and Maantang formations is type Ⅱ and that of the Xiaotangzi Formation is type Ⅱ–Ⅲ. The maturity parameters and the hopane and sterane isomerization suggest that the OM was advanced mature and produced wet–dry gases. One-dimensional modeling of the thermal-burial history suggests that hydrocarbon-generation occurred at 220–60 Ma. The gas components and C–H–He–Ar–Ne isotopes indicate that the oilassociated gases were generated in the Leikoupo and Maantang formations, and then, they mixed with gases from the Xiaotangzi Formation, which were probably contributed by the underlying Permian marine source rocks. Therefore, the deeply-buried Middle–Late Triassic marine source rocks in the western Sichuan depression and in similar basins have a great significant hydrocarbon potential.  相似文献   

6.
The Yinggehai Basin is a strongly overpressured Cenozoic basin developed in the northern continental shelf of the South China Sea. The flow of overpressured fluids in this basin has given rise to strong effects on petroleum accumulation. (1) The overpressured fluid flow has enhanced the maturation of shallow-buried source rocks, which has caused the source rocks that would have remained immature under the conduction background to be mature for hydrocarbon generation. As a result, the overpressured fluid flow has increased the volume and interval of mature source rocks. (2) The overpressured fluid flow has strong extraction effects on the immature or low-mature source rocks in the shallow parts. This has increased, to some extent, the expulsion efficiency of the source rocks. More importantly, the extraction effects have strongly limited the effectiveness of biomarker parameters from oil and condensate in reflecting the source and maturity of the oil and gas. (3) The flow has caused the sandstones in the  相似文献   

7.
Located in Iranian sector of the Persian Gulf, Foroozan Oilfield has been producing hydrocarbons via seven different reservoirs since the 1970s. However, understanding fluid interactions and horizontal continuity within each reservoir has proved complicated in this field. This study aims to determine the degree of intra-reservoir compartmentalization using gas geochemistry, light hydrocarbon components, and petroleum bulk properties, comparing the results with those obtained from reservoir engineering indicators. For this purpose, a total of 11 samples of oil and associated gas taken from different producing wells in from the Yammama Reservoir were selected. Clear distinctions, in terms of gas isotopic signature and composition, between the wells located in northern and southern parts of the reservoir (i.e. lighter δ13C1, lower methane concentration, and negative sulfur isotope in the southern part) and light hydrocarbon ratios (e.g. nC7/toluene, 2,6-dmC7/1,1,3-tmcyC5 and m-xylene/4-mC8) in different oil samples indicated two separate compartments. Gradual variations in a number of petroleum bulk properties (API gravity, V/Ni ratios and asphaltene concentration) provided additional evidence on the reservoir-filling direction, signifying that a horizontal equilibrium between reservoir fluids across the Yammama Reservoir is yet to be achieved. Finally, differences in water-oil contacts and reservoir types further confirmed the compartmentalization of the reservoir into two separate compartments.  相似文献   

8.
Coal-bearing source rocks of the Pinghu Formation in the Xihu Depression comprise an important material basis of oil and gas resources in the East China Sea Basin.Based on drilling core observation results combined with the analysis and test results of macerals,trace/rare earth elements,and rock pyrolysis,the geochemical characteristics and sedimentary control of coal-bearing source rocks formation are discussed in a high-frequency sequence framework.The results indicate that the macerals composition of the coal-bearing source rocks of the Eocene Pinghu Formation in the Xihu Depression is dominated by vitrinite,with low-medium abundance of exinite and almost no inertinite.The coals and carbonaceous mudstones display higher amounts of total organic carbon(TOC)(14.90%-65.10%),S1+S2(39.24-136.52 mg/g),and IH(191-310 HC/g TOC)respectively,as compared to the mudstones.Organic matter is plotted in typeⅢkerogens and partially in typeⅡ;it is mainly in the low maturity stage.The trace elements results imply that the samples were deposited in a weakly reducing to weakly oxidizing environment and were occasionally affected by seawater.The coal-bearing source rocks were deposited in a relatively oxygen-containing environment.The coal-bearing source rocks development is jointly controlled by the coal accumulation environment,the water conditions affected by ocean currents in offshore basins in China,oxidation-reduction cycles of aqueous media and paleoclimate evolution in a high-frequency sequence framework.  相似文献   

9.
There are known to be enormous Cenozoic coal-type oil and gas resources located in the basins of the South China Sea,among which the Paleogene coal-measure source rock are one of the main source rock.In order to more effectively analyze the distribution laws of coal-measure source rock in marginal sea basins and guide coal-type oil and gas explorations,the Oligocene coal-measure source rock in the Qiongdongnan Basin were selected as examples in order to systematically analyze the types,development characteristics,control factors,and distribution prediction methods of coalmeasure source rock in marginal sea basins.The Qiongdongnan Basin is located in the northern region of the South China Sea.Previous explorations of the area have determined that the Oligocene coal-measure source rock in the Qiongdongnan Basin have typical"binary structures",which include coal seams and terrigenous marine mudstone.Among those,the terrigenous marine mudstone has been found to greatly expand the scope of the coal-measure source rock.In addition,the coal seams which have been exposed by drilling have been observed to have the characteristics of thin single layer thickness,many layers,and poor stability.Meanwhile,the terrigenous marine mudstone has the characteristics of large thickness and wide distribution.The development of coal-measure source rock is known to be controlled by many factors,such as paleoclimate and paleobotany condition,paleo-structure and topography,paleo-geography,rise and fall of base level,and so on.In accordance with the comprehensive analyses of various control factors of coal-measure source rock,and the changes in water body energy in sedimentary environments,a genetic model of the"energy belt"for the development and distribution of coal-measure source rock was proposed.Also,the development and distribution characteristics of coalmeasure source rock in different types of energy belts were clarified.Then,based on the development and distribution characteristics of coal-measure source rock and their controlling factors,prediction methods of the distribution ranges of coal-measure source rock were proposed from both qualitative and(semi-)quantitative aspects.That is to say,a method for(semi-)quantitative predictions of the distribution ranges of coal-bearing intervals based on model wave impedance inversion and neural network wave impedance inversion,along with a method for(semi-)quantitative predictions of the distribution ranges of terrigenous marine mudstone based on topographical slopes,were introduced in this study.  相似文献   

10.
<正>Condensates and light oils are generally characterized by high maturity,low concentration of sterane and terpane biomarkers and low content of non-hydrocarbon fraction.As a result,some commonly-used sterane,terpane and carbazole migration parameters in conventional oil reservoirs may have a certain limitation in condensate and light oil reservoirs for their poor signal-noise ratios in the gas chromatography-mass spectrometry(GC-MS).Naphthalene,phenanthrene and their methylated substituents,however,are present in significant concentrations in condensates and light oils.Taking the Fushan depression(in the Beibuwan Basin,Northern South China Sea) as an example, this paper attempts for the first time to use polycyclic aromatic hydrocarbon(PAH)-related parameters to trace migration directions and filling pathways for condensate and light oil reservoirs.The result shows that TMNr(i.e.1,3,7-TMN/(1,3,7-TMN + 1,2,5-TMN),TMN:trimethylnaphthalene)),MPI-1 (i.e.1.5×(2-MP + 3-MP)/(P + 1-MP + 9-MP),P:phenanthrene MP:methylphenanthrene),MN/DMN (Σmethylnaphthalene/Σdimethylnaphthalene,%) and MN/TMN(Σmethylnaphthalene/Σtrimethylnaphthalene, %) can be used to trace the filling pathways of condensate and light oil reservoirs.These parameters,together with geological consideration and other bulk oil properties(e.g.the gas to oil ratio and density),suggest that the condensates and light oils in the Huachang oil and gas field are mainly sourced from the Bailian sag that is located to the northeast of the Huachang uplift in the Fushan depression.  相似文献   

11.
在分析和总结前人对红藻石和蓝藻石研究成果基础上,结合岩石薄片显微镜下观察实例,发现在以往碳酸盐岩颗粒分类中没有红藻石和蓝藻石的合适位置。鉴于红藻石重要的成因意义和造礁作用,有必要明确红藻石的概念和归属。珊瑚藻本身极易钙化,经生物矿化作用最终保存下来的珊瑚藻屑一直放在生物碎屑中,而红藻石是由非固着的珊瑚藻构成的钙质独立结核,因此也可以被划分到生物碎屑中。蓝藻石作为蓝细菌钙化作用的产物,同时鉴于蓝藻石的广泛存在,把钙化蓝细菌形成的核形石命名为蓝藻石,这一重要概念从提出到现在一直被使用。然而蓝绿藻概念已变更为蓝细菌,蓝藻石的形成与藻类无关,显然将其称作蓝菌石更加确切。因此,应将红藻石和蓝藻石分别归为生物碎屑和核形石当中,并用新的术语蓝菌石替代蓝藻石。其意义在于使红藻石和蓝藻石的概念及归属更为规范,并为碳酸盐岩颗粒的深入研究提供有益线索。  相似文献   

12.
宋兵  蔡健 《岩土力学》2011,32(8):2313-2318
研究桩与岩石的侧摩阻力组成及影响因素,有助于准确地把握桩与岩石的侧摩阻力取值原则。在对桩与岩层的摩擦黏着机制分析的基础上,指出界面力与岩层抗剪力的区别,并提出岩层的极限侧摩阻力由界面强度及岩石强度两者较弱一方决定的观点。进行了中风化岩中4组混凝土短桩的抗压及抗拔极限摩阻力对比试验,获得了相应的极限侧摩阻力值以及抗拔与抗压极限侧摩阻力值的比值。抗拔时由于上部岩层对桩侧岩层的约束作用较弱,会使侧摩阻力相对抗压时有较大降低。通过有限元计算及其与试验值的比较分析,研究短桩与岩层的界面强度条件,发现岩层和混凝土灌注桩间的侧摩阻力中界面黏着力占很大比例。  相似文献   

13.
宝玉石产地来源的研究是近几年地质学、宝石学和考古学界的热门话题之一。一方面，不同产地来源的宝玉石可能具有不同的品质特征及经济价值，其研究有助于珠宝首饰价值的判断，为各国海关执法提供技术支持；另一方面，古代宝玉石产地的确定对了解古代宝玉石的开采与古代科技的发展水平及不同区域的文化交流均具有重要意义。在总结前人研究成果的基础上，结合现代微区测试技术的最新研究成果，从微量元素、包裹体以及同位素分析等方面探讨总结了微区测试技术在确定宝玉石产地来源研究中的应用。当前的研究结果显示，不同的技术方法对确定宝玉石的产地来源均有一定的意义，但宝玉石产地来源的最终确定往往需要依赖更大范围和更深入地对宝石矿床的地球化学进行多技术手段的交叉分析。显然，确定各种不同类型宝玉石产地来源的标型特征及建立相关重要宝石产地的地球化学数据库，是最终解决宝玉石产地来源鉴定问题的关键。  相似文献   

14.
RS和GIS技术集成及其应用   总被引：13，自引：3，他引：10  
本文简要地介绍了ＲＳ（遥感图像处理系统）和ＧＩＳ（地理信息系统）技术及其集成的基本概念和方法。讨论了ＲＳ和ＧＩＳ技术及其集成的内在涵义、相互关系,认为ＲＳ是ＧＩＳ重要的外部信息源,是其数据更新的重要手段,尤其对于全球性的 地理动力学分析,更必须有ＲＳ所提供的覆盖全球的动态数据与ＧＩＳ的结合。反之,ＧＩＳ则可以提供ＲＳ所需要的一些辅助数据,以提高ＲＳ图像的信息量和分辨率,同时,ＧＩＳ可以将实地调查所  相似文献   

15.
In June 2014, the "Statistics System for the Damage and Loss of Large-scale Natural Disasters" (SSDLLND) was issued by the Ministry of Civil Affairs and the Office of National Disaster Reduction Committee, which marked that the statistics and assessment of China's catastrophic natural disaster damage and losses formally entered a new stage of institutionalization. On the basis of analyzing the five major international disaster damage and loss assessment systems, including HAZUS-MH, ECLAC, DaLA, EMA-DLA and PDNA, the differences between the “SSDLLND” of China and five major international systems were compared from the statistics and assessment contents and indicators. Combined with the statistics and assessment practices of China’s large-scale disaster damage and losses and the characteristics of international systems in recent years, the future development of the SSDLLND were proposed in three aspects: Enriching and improving the framework of damage and loss statistics content, stepwise improvement of disaster impact assessment methods (such as the ecological capital loss assessment, tourism industry loss assessment due to the disasters, etc.), and improving indicators and parameters of loss statistics. The study has an important practical significance for improving the statistics and assessment system of the damage and loss of major natural disasters and better serving the post-disaster recovery and reconstruction decision-making.  相似文献   

16.
This paper considers an ellipse, produced by the intersection of a triaxial ellipsoid and a plane (both arbitrarily oriented), and derives explicit expressions for its axis ratio and orientation. The relationship between central and noncentral sections, and the problem of intersection probability, are discussed. The resulting equations have obvious applications in structural geology and optical mineralogy, and in stereological modeling of grain-size and grain-shape distributions.  相似文献   

17.
In the history, the Yellow River nurtured Chinese civilization. It is respected as the ＂ancestor of the four large rivers in China＂ and praised as ＂the mother river of China＂. At the same time, the Yellow River is regarded as ＂the misery of China＂ and considered as the most complex river hard to control in the world. Today, the Yellow River is also one large river greatly influenced by human activities in the world. The safety of the Yellow River, particularly flood control, is always the most important issue for governing and developing the country. Great achievements have been made after many years of efforts for controlling the Yellow River. However, since the nineties of 20 century, some new problems occurred, such as sharp reduction of flux to sea, dry rivercourse, worsen environment, etc. Rapidly shrinking riverbed and two-level perched stream are disadvantageous to flood safety especially. The new concepts and new practices are urgently needed to control the river. Therefore, the Yellow River Conservancy Committee of Ministry of Water Resources had continuously carded out flow and sediment diversion each year from 2002 to 2005. To timely probe into the new issues produced after flow and sediment diversion, and in order to deepen the understanding of rules for the Yellow River＇s water and sediment and provide reference and experience to the researchers for other large rivers, five hydrologic and hydraulic characteristics of the Yellow River, such as lack of water, much of sediment, different resources of water and sediment, inconsistency between water and sediment and frequency of sink switching and route changing, are described. Flow and sediment diversion of the Yellow River is also reviewed. Under flow and sediment diversion,  相似文献   

18.
贵州省地矿局建局63年以来,钻探工程作为地质找矿的重要技术手段,发展至今已形成门类齐全、设备精良、技术精湛的专业体系。本文在总述贵州省地矿局地质找矿辉煌成就的基础上,从小口径岩心钻探、大口径深井钻探、地下水机井钻探、浅层地温能钻探等几个重点方面详细回顾了钻探工程的发展历程,对未来发展趋势进行了展望,同时提出了相关的建议,以供今后的工作参考。  相似文献   

19.
对不同温度(90~200℃)和压力(20~120 MPa)条件下的富甲烷天然气在碳酸氢钠溶液中的溶解度值进行了实验测定,阐述了甲烷溶解度随温度、压力及矿化度的变化特征。综合前人的实验结果,将天然气的溶解度与温度的关系划分为3个阶段:①缓慢递减阶段(0~80℃);②快速递增阶段(>80~150℃);③缓慢递增阶段(>150℃)。在温压的共同作用下,溶解度随埋藏深度的增加,也具有不同的阶段变化特征;且当地层水温度、压力足够高时,甲烷的溶解能力趋近于某一极限值。利用甲烷溶解度回归方程有助于对不同地区水溶气析离脱气界限的估算。我国主要存在包括侧向阶段脱气、断裂-底辟脱气、盖层渗滤脱气和构造抬升脱气4种与构造和渗滤作用有关的水溶气析离成藏模式。  相似文献   

20.
王小平  夏雄 《岩土力学》2011,32(11):3283-3287
岩土类材料具有显著的率相关性,其应力-应变关系全过程一般表现为硬化-软化特征,研究如何描述这两类特征具有重要的意义。基于岩土类材料的物理变形机制分析,考虑到其结构性特征,采用弹黏塑性本构模型,引入反映材料结构变化的可变结构黏滞系数及其演化方程,并将其嵌入到弹黏塑性本构模型中去,建立能够反映材料结构变化的弹黏塑性本构模型。利用玄武岩常规三轴常应变率试验结果对所建立的模型进行试验验证,结果表明:所建立的弹黏塑本构模型能够完整、合理地描述岩土类材料应力-应变关系全过程以及材料本构关系的率相关性,同时还能够反映材料的峰值强度、残余强度特征。  相似文献   

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