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81.
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   
82.
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   
83.
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   
84.
毛景文  宋世伟  刘敏  孟健寅 《地质学报》2022,96(11):3675-3697
本文介绍了全球稀土资源供需历史、现状和对未来的展望。从矿床成因视角切入,将稀土矿床分为内生和外生两大类型,其中内生稀土矿床包括碳酸岩型、碱性岩型、碱性岩型- 碳酸岩型、氧化铁铜金型、热液脉型,外生稀土矿床包括风化壳离子吸附型、沉积岩型、沉积矿产(煤矿、铝土矿和沉积磷矿)伴生型、砂矿和现代海洋底部含稀土的锰结核、结壳和软泥型。归纳总结了主要类型矿床的基本特点和时空分布;认为内生稀土矿床产出于四类构造环境,包括裂谷环境、碰撞后伸展环境、大陆碰撞环境和后俯冲伸展环境;从构造演化入手,探讨了在外生与内生地质过程中稀土元素的迁移和富集规律,建立了涵盖主要矿床类型的构造- 成矿模型。  相似文献   
85.
付伟  赵芹  罗鹏  李佩强  陆济璞  周辉  易泽邦  许成 《地质学报》2022,96(11):3901-3923
传统认为中国南方的离子吸附型稀土矿床可划分为以“足洞式”为代表的重稀土型和以“河岭式”(或“花山式”)为代表的轻稀土型两种矿化类型。然而,近年来发现的许多矿床(如清溪、寨背和馒头山等)的赋矿风化壳中出现了轻稀土矿与重稀土矿并存现象,表现出特殊的“上轻下重”双层矿体结构。这指示了除重稀土型和轻稀土型之外,还存在着轻重稀土共生型的过渡类型。本研究通过对三种不同成矿类型的若干典型矿床系统对比,指出成矿类型的多样性与母岩性质密切相关,尤其是母岩的稀土元素地球化学和稀土载体矿物属性是制约成矿类型变化的关键因素。统计数据表明,从重稀土型→轻重稀土共生型→轻稀土型,成矿母岩的全岩稀土总量变化不大(ΣREY: 200×10-6~450×10-6→200×10-6~500×10-6→200×10-6~800×10-6),但轻重稀土配分值出现较显著的区间性差异(ΣLREE/ΣHREY: 02~1→1~5→2~10)。与之同时,母岩中能为离子相稀土提供物源且具有重稀土配分属性的稀土副矿物类型和数量明显减少,这与全岩稀土元素地球化学特征中重稀土分量占比的降低趋势也互相匹配。该结果指示,以往认为重稀土配分母岩形成重稀土矿床、轻稀土配分母岩形成轻稀土矿床的传统观点需要外延,即一部分具有低度轻稀土配分属性(1<ΣLREE/ΣHREY<5)且含有丰富易风化稀土副矿物的母岩还可能形成轻重稀土共生型矿床,该认识可为今后离子吸附型稀土矿床勘查工作提供新的找矿依据。  相似文献   
86.
矿物标型六性及其在胶东金矿中的应用   总被引:2,自引:0,他引:2  
目前矿物标型研究和应用已进入一个新的阶段。作者从哲学的高度,把国内外矿物标型特征的分散研究加以集中概括和总结,提出了“矿物标型六性”的普遍规律,即普遍性、特殊性、变化性、相应性、继承性和分带性,对矿物标型特征研究具重要的指导意义。这些规律在胶东金矿中得到广泛应用,并已取得良好效果。  相似文献   
87.
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   
88.
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   
89.
The Taojiang Mn ore deposit was exploited in the early 1960s, and waste rocks were developed since then. Because the Mn ores were hosted within the metal-enriched black shales (Peng et al., 2004), the continuous mining has led to the exposure of an immense quality of black shales, which might cause serious impacts on environments. The present study deals with this environmental issue with samples from the waste rocks, and from the surrounding soils and surface water. The mineralogy of the waste rock was studied using EMPA, then a large number of elements in all waste rock, soil, and water samples were analyzed at a wide range of concentrations with high accuracy using an Elan6000 ICP-MS machine at Guangzhou Institute of Geochemistry, Chinese Academy of Sciences. The waste rock is composed mostly of black shales, with minor Mn carbonates. Both black shales and Mn carbonates of the waste rock contain many sulfide minerals, mainly pyrite, with minor galena, sphalerite, chalcopyrite, and others. The waste rocks are enriched in many metals including Sc, V, Cr, Co, Ni, Fe, Mn, Cu, Zn, Pb, Th, U, Mo, Sb, Sn, Tl, and others, and the metals are mostly hosted within the sulfides. Weathering of waste rocks might cause emission of the following metals: V, Cd, Ni, Th, U, Mo, Sb, Tl, Sc, Cr, Cu, Zn, Sn, and minor Co, and Pb. The surrounding soils are highly enriched in Cr, Co, Cu, Zn, Mn, Mo, Cd, Tl, and Pb, with the enrichment factors of 2.67.3.8, 7.26, 7.27, 8.2, 5.7, 13, and 5.4, respectively. The element ratios (Rb/Cs, Fe/Mn, Nb/Zr, Hf/Zr, and Ba/Sr) and REE distribution patterns of the soils are similar to those of the waste rocks and bedrocks.  相似文献   
90.
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   
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