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51.
轮南地区油气相态分布非常复杂,奥陶系油气藏平面上具有西油东气的特点。西部轮古西油田、塔河油田和轮南1井区油族成熟度略低且有生物降解痕迹,主要以重油形式分布;东部地区油族成熟度略高,主要以轻质油、凝析油形式存在;中间地段桑塔木断垒带、中部平台区和轮南断垒带发生混合作用形成了中一高蜡油。各地区油气在垂向上变化很大,东部地区奥陶系和石炭系为凝析油气,三叠系又为正常油分布区;西部地区奥陶系为稠油,三叠系为正常油。轮南地区奥陶系在纵向上可能受控于岩溶和储层的发育程度,横向上受控于断裂作用。轮南地区油气成藏时间较早,不同物性的原油都是古油藏多期供油的结果。 相似文献
52.
Non-Linear Theory and Power-Law Models for Information Integration and Mineral Resources Quantitative Assessments 总被引:7,自引:0,他引:7
Qiuming Cheng 《Mathematical Geosciences》2008,40(5):503-532
Singular physical or chemical processes may result in anomalous amounts of energy release or mass accumulation that, generally,
are confined to narrow intervals in space or time. Singularity is a property of different types of non-linear natural processes
including cloud formation, rainfall, hurricanes, flooding, landslides, earthquakes, wildfires, and mineralization. The end
products of these non-linear processes can be modeled as fractals or multifractals. Hydrothermal processes in the Earth’s
crust can result in ore deposits characterized by high concentrations of metals with fractal or multifractal properties. Here
we show that the non-linear properties of the end products of singular mineralization processes can be applied for prediction
of undiscovered mineral deposits and for quantitative mineral resource assessment, whether for mineral exploration or for
regional, national and global planning for mineral resource utilization. In addition to the general theory and framework for
the non-linear mineral resources assessment, this paper focuses on several power-law models proposed for characterizing non-linear
properties of mineralization and for geoinformation extraction and integration. The theories, methods, and computer system
discussed in this paper were validated using a case study dealing with hydrothermal Au mineral potential in southern Nova
Scotia, Canada. 相似文献
53.
The tbough one year cormsion potential and polarisation resistanoc for 3 kinds of stals in seabottomedment of Liaodong Bay were measured with the “MD” method.The measurements wiIl have some thoretical and pndital talues. The thooretical valoc lies in thatthe reoorded changing process of the practital corrosion case can be basis for indoor discussion andeectrochemical on the corrosion practical value lies in that the obtained datu canbe basis for designing and controlling elatrochemical protation syttems. In fact, it is very difficult tomeasure in situ the cornosion parnders of steeIs in sea sediment. 相似文献
54.
In this paper analytical expressions are derived for the temporal variations ofJ
2 andJ
22 due to the tides of the solid Earth, taking into account only the deformation of the mantle, and employing a procedure already used by the authors in their Hamiltonian theory of the Earth's rotation, which obtain the necessary parameters in a direct way by integration of those provided by a selected model of Earth interior.Numerical tables giving the periodic variation of coefficients are given, as well as a new prediction for UT1. For J
2 and J
22 the amplitudes reach such a magnitude that both two variations should not be ignored in studies involving the analysis of highly precise satellite tracking data. Moreover, the possibility of improving our knowledge of the value of those harmonic coefficients in only a more exact digit appears as to be strongly dependent on the limitations in the theoretical modeling of the variations of the inertia tensor due to solid tides. 相似文献
55.
南海盆地及周缘地区新生代玄武岩对揭示南海盆地的演化历史至关重要,然而这些玄武岩的成因还存在争议。本文研究了位于南海北部陆缘的海南岛临高县多文组玄武岩岩石地球化学和矿物地球化学特征,并探讨其成因和构造背景。多文组玄武岩主要由橄榄石、单斜辉石、斜长石、斜方辉石、铬尖晶石和铁钛氧化物等组成。橄榄石Fo值变化于55. 5~71. 1之间,Ni的含量较低, Fe/Mn比值较高。铬尖晶石Cr#值为74. 1~82. 7,Mg#值为45. 5~63. 8, Ti的含量较高。斜方辉石Mg#值为63. 9~79. 6,单斜辉石为66. 0~80. 6。单斜辉石稀土配分曲线富集MREE,亏损LREE和HREE,呈拱形分布。斜长石以中- 拉长石为主(Ab36. 56~52. 78), 富集LREE、Ba、Sr和Eu。铁钛氧化物的TiO2含量为50. 19%~51. 46%。多文组玄武岩原始岩浆的主量和微量元素组成与夏威夷、峨眉山、塔里木等玄武岩组成一致,地幔源区包含了辉石岩的成分,而且其地幔潜在温度(>1400℃)和氧逸度(ΔNNO)要高于大洋中脊玄武岩(N- MORB),表明多文组玄武岩的形成与海南地幔柱活动有关。由于海南地幔柱形成时代明显晚于南海盆地的扩张时代,认为南海地幔柱是南海盆地伸展的被动响应。 相似文献
56.
We consider the problem of finding the generalized potential function V = U
i(q
1, q
2,..., q
n)q
i + U(q
1, q
2,...;q
n) compatible with prescribed dynamical trajectories of a holonomic system. We obtain conditions necessary for the existence of solutions to the problem: these can be cast into a system of n – 1 first order nonlinear partial differential equations in the unknown functions U
1, U
2,...;, U
n, U. In particular we study dynamical systems with two degrees of freedom. Using adapted coordinates on the configuration manifold M
2 we obtain, for potential function U(q
1, q
2), a classic first kind of Abel ordinary differential equation. Moreover, we show that, in special cases of dynamical interest, such an equation can be solved by quadrature. In particular we establish, for ordinary potential functions, a classical formula obtained in different way by Joukowsky for a particle moving on a surface.Work performed with the support of the Gruppo Nazionale di Fisica Matematica (G.N.F.M.) of the Italian National Research Council. 相似文献
57.
The petroleum generation potential and effective oil window of humic coals related to coal composition and age 总被引:1,自引:0,他引:1
A worldwide data set of more than 500 humic coals from the major coal-forming geological periods has been used to analyse the evolution in the remaining (Hydrogen Index, HI) and total (Quality Index, QI) generation potentials with increasing thermal maturity and the ‘effective oil window’ (‘oil expulsion window’). All samples describe HI and QI bands that are broad at low maturities and that gradually narrow with increasing maturity. The oil generation potential is completely exhausted at a vitrinite reflectance of 2.0–2.2%Ro or Tmax of 500–510 °C. The initial large variation in the generation potential is related to the original depositional conditions, particularly the degree of marine influence and the formation of hydrogen-enriched vitrinite, as suggested by increased sulphur and hydrogen contents. During initial thermal maturation the HI increases to a maximum value, HImax. Similarly, QI increases to a maximum value, QImax. This increase in HI and QI is related to the formation of an additional generation potential in the coal structure. The decline in QI with further maturation is indicating onset of initial oil expulsion, which precedes efficient expulsion. Liquid petroleum generation from humic coals is thus a complex, three-phase process: (i) onset of petroleum generation, (ii) petroleum build-up in the coal, and (iii) initial oil expulsion followed by efficient oil expulsion (corresponding to the effective oil window). Efficient oil expulsion is indicated by a decline in the Bitumen Index (BI) when plotted against vitrinite reflectance or Tmax. This means that in humic coals the vitrinite reflectance or Tmax values at which onset of petroleum generation occurs cannot be used to establish the start of the effective oil window. The start of the effective oil window occurs within the vitrinite reflectance range 0.85–1.05%Ro or Tmax range 440–455 °C and the oil window extends to 1.5–2.0%Ro or 470–510 °C. For general use, an effective oil window is proposed to occur from 0.85 to 1.7%Ro or from 440 to 490 °C. Specific ranges for HImax and the effective oil window can be defined for Cenozoic, Jurassic, Permian, and Carboniferous coals. Cenozoic coals reach the highest HImax values (220–370 mg HC/g TOC), and for the most oil-prone Cenozoic coals the effective oil window may possibly range from 0.65 to 2.0%Ro or 430 to 510 °C. In contrast, the most oil-prone Jurassic, Permian and Carboniferous coals reach the expulsion threshold at a vitrinite reflectance of 0.85–0.9%Ro or Tmax of 440–445 °C. 相似文献
58.
位场自动反演技术的研究现状及意义 总被引:4,自引:0,他引:4
本文首先叙述了重、磁异常自动反演技术的特点。与传统的定性分析重、磁场分布特征的方法不同,重、磁异常自动反演方法通过反演得到地下场源分布,即地下密度或磁性的分布特征。由于密度体或磁性体与地质体的关系更为直接,因此这种新一代重、磁解释成果及图件将成为人们从新的角度来认识地质构造的基础材料。文中不但阐述了该方法的研究现状,同时也说明了存在的问题。 相似文献
59.
G. Günay 《Environmental Geology》2006,51(2):229-240
The Sakarya River is one of the largest rivers in Turkey and is fed mainly from Sakaryabaşı springs. The Sakaryabaşı springs are located in the Central Anatolia and issue from confined/semi-confined karst having a thermal component and therefore, having quite different hydrogeological characteristics as compared to the Taurus Karst region, a typical example of the Mediterranean type of karst. The karstic carbonate rocks that form the groundwater reservoir are overlain by a thick semi-pervious overburden of mainly clastics of Neogene age. Tectonics is the major factor controlling the occurrence of the karst springs in the area where topography is rather flat. This study aimed at explaining the occurrence and movement of the karst groundwater within the system by use of hydrogeological, chemical, and isotopic tools. Isotopic composition of the waters revealed that all waters in the region are of meteoric origin and the thermal component is due to deep circulation. The catchment area of the hydrogeological system extends to the south and groundwater movement is towards the outlets, which are in a depression along a major fault. The movement of the groundwater, based on analysis of remotely sensed images, is controlled mainly by structural elements. 相似文献
60.
Joo Carvalho Joo Cabral Rui Gonalves Luís Torres Luís Mendes-Victor 《Tectonophysics》2006,418(3-4):277-297
The study region is located in the Lower Tagus Valley, central Portugal, and includes a large portion of the densely populated area of Lisbon. It is characterized by a moderate seismicity with a diffuse pattern, with historical earthquakes causing many casualties, serious damage and economic losses. Occurrence of earthquakes in the area indicates the presence of seismogenic structures at depth that are deficiently known due to a thick Cenozoic sedimentary cover. The hidden character of many of the faults in the Lower Tagus Valley requires the use of indirect methodologies for their study. This paper focuses on the application of high-resolution seismic reflection method for the detection of near-surface faulting on two major tectonic structures that are hidden under the recent alluvial cover of the Tagus Valley, and that have been recognized on deep oil-industry seismic reflection profiles and/or inferred from the surface geology. These are a WNW–ESE-trending fault zone located within the Lower Tagus Cenozoic basin, across the Tagus River estuary (Porto Alto fault), and a NNE–SSW-trending reverse fault zone that borders the Cenozoic Basin at the W (Vila Franca de Xira–Lisbon fault). Vertical electrical soundings were also acquired over the seismic profiles and the refraction interpretation of the reflection data was carried out. According to the interpretation of the collected data, a complex fault pattern disrupts the near surface (first 400 m) at Porto Alto, affecting the Upper Neogene and (at least for one fault) the Quaternary, with a normal offset component. The consistency with the previous oil-industry profiles interpretation supports the location and geometry of this fault zone. Concerning the second structure, two major faults were detected north of Vila Franca de Xira, supporting the extension of the Vila Franca de Xira–Lisbon fault zone northwards. One of these faults presents a reverse geometry apparently displacing Holocene alluvium. Vertical offsets of the Holocene sediments detected in the studied geophysical data of Porto Alto and Vila Franca de Xira–Lisbon faults imply minimum slip rates of 0.15–0.30 mm/year, three times larger than previously inferred for active faults in the Lower Tagus Valley and maximum estimates of average return periods of 2000–5000 years for M 6.5–7 co-seismic ruptures. 相似文献