共查询到20条相似文献，搜索用时 140 毫秒
1.
现在提出了利用不同的参数来定量评价放射性异常的远景。这些参数有:测到的γ放射性的极大值,晕的含矿性和放射性异常的延拓。在所有的情况下,评价的可靠性取决于在代表性层面上进行的普查工作的可靠性。确定代表性层位埋深的一个因素是疏松沉积层的厚度。在山区森林的分水岭和山坡地区,疏松层的厚度一般为0.5至5.0米。由于所研究的各种山区森林的地形占有的面积为总面积的30—70%,所以评价疏松沉积物的厚度对用放射性测量γ 相似文献
2.
本文的目的是提供介绍减少降雨派生的渗漏和流入的努力有效评估方法及目前的一些修复项目的结果。方法的解释是为那些准备和考虑对于修复结果的流量数据进行评估的人作为一个引物。方法的讨论范围从基本的线综述到风暴数据的评估及控件的使用。成为修复计划或是考虑实际工程的应用及他们的并发症。结果来源于被呈现的降雨派生的渗漏和流入的峰值的缩减范围从14％到61％及降雨派生的渗漏和流入的体积缩减范围从42％到70％的7个修复项目和阶段。 相似文献
3.
红外吸收光谱是各种化合物的最重要的特征。根据化合物的红外吸收光谱,研究各种物质的结构和成分,已是重要的现代方法之一。随着仪器的不断改进和样品制备技术的日益完善,红外光谱在矿物学研究的应用上日趋广泛。不同的矿物有着不同的红外吸收光谱。单个矿物红外光谱的唯一性是鉴定矿物的主要依据。在光谱的红外区域被矿物吸收的射线的波长与晶体中分子或原子间的振动有关。 相似文献
4.
含不同半径孔洞的颗粒体模型的力学行为数值模拟 总被引：3，自引：0，他引：3
本文通过编程建立了非连续介质(颗粒体材料)模型,采用FLAC软件模拟了静水压力条件下不同半径的巷道围岩中的剪切应变增量、最小主应力及最大主应力的分布规律。研究表明,随着孔洞半径的增大,呈圆环形的剪切应变增量与最小主应力的高值区的圈数、呈辐射状的最大主应力的高值区的延伸范围及剪切应变增量的最大值都呈先慢后快的增长趋势。模型中最大的拉应力接近于在模型四周所施加的压应力,而最大的压应力约为所施加的压应力的5～10倍。模型内部的剪切应变增量、最小主应力及最大主应力的分布是高度不均匀的。具有较高的差应力的位置与具有较高的剪切应变增量的位置具有很好的一致性。 相似文献
5.
在热催化高温燃烧TOC分析中，我们所面临的最棘手的问题是如何避免气体流速的波动对检测结果的影响。而影响气体的流速有下列因素：①由于高温燃烧，短时间所产生的气体的快速蒸发；②由于样品基体的不同，所产生的流速的变化；③由于管路上堵塞所引起的流速的变化；④催化剂形状的变化，所引起的流速的变化。 相似文献
6.
试论矿田断裂地球化学 总被引：4，自引：0，他引：4
构造地球化学这株刚萌芽的幼苗正以其强大的生命力引起国内外地质工作者的重视.构造地质学是研究地壳运动规律的科学;地球化学则是研究组成地壳的化学元素——原子运动规律的科学.十分明显,这种宏观的岩块、地块的运动与组成它们的基本单位——原子的微观世界的运动之间必然存在着密切的内在联系.我们可以看到,世上的超基性岩都沿深断裂带分布;火山岩都出现在地壳的某些活动区;与岩浆活动有关的内生金属矿产大多和地壳一定的构造带息息相关,如智利、赞比亚和乌拉尔的铜矿带和我国南岭的稀有-有色金属矿带部是引人注目的例子.即使在一个矿床的形成过程中,不同的构造阶段亦常有不同的元素富集,而且这种构造-岩浆-矿液的发展演化往往具有十分明显的规律性.这些现象并非偶然的巧 相似文献
7.
新世纪地球科学视野中的新技术和新方法(代序) 总被引：4，自引：0，他引：4
从科学发展战略的角度 ,讨论了新技术、新方法在地球科学中的应用。新世纪的地球科学在新技术、新方法的应用方面呈现出鲜明的时代特色 ,即观测范围的扩大与观测能力的增强 ,多学科观测的海量数据的积累与地球观测系统的整合 ,不断增强的挑战非线性复杂地球系统中的预测问题的能力。特别是 ,作为地球观测系统的整合的“数字地球”和作为地球过程的模拟工具的高效并行计算 ,将在地球系统科学的发展中发挥重要作用。从方法论的角度 ,文中特别指出 ,只有掌握新技术、新方法的人对新技术、新方法有正确的理解 ,并具有创新性的思维 ,新技术、新方法才能发挥其应有的效能。 相似文献
8.
9.
信息价值论初探：关于矿产资源价值的理论思考 总被引：2，自引：2，他引：0
信息价值论认为,凝结着人类劳动知识信息的自然资源、矿产资源是价值的有,人类的生产和消费活动既不能创造物质,也不能消灭物质,只是生产和消费信息的有序性,产品的价值是由产品信息的有序性决定的。而不是由投入的活劳动和物化劳动量决定的。产品的价格是由买卖双方共同认定的信息的有序性来决定。市场中价格背离价值的现象是因买卖双方占有信息的不对称所造成的。生产要素价值的本质是收入分配,以土地为代表的自然资源资本之 相似文献
10.
用于评价污染降解速率的内部示踪法与和降解无关的衰减效应有区别的，该方法是通过使用一种似抗体的内部示踪剂来使降解的污染浓度达到正常化。内部示踪剂与降解的污染物之间保持的衰减应归因于降解效应，并且通过一阶延时方程来评价降解速率的半衰期。平移一迁移方程的解析解被用于评价水流和运移状态。这一状态可能会导致对污染降解速率常数的不正确估价。水流运移特征导致的对降解速率的高估是非常值得重视的，因为常用于解释自然衰减作用的内部示踪法可以达到补救的目的。解析解也通常用于评价与某一示范站使用内部示踪剂相关的误差的量级，并且解释使用不同的延时速率常数的示踪剂的不同的降解速率的评价。 相似文献
11.
We examine the formation of the Michigan Basin in terms of elastic flexure of the lithosphere. The shape of the flexure accurately determines the flexural rigidity of the lithosphere and the lateral extent of the load responsible for the flexure. The amplitude of differential subsidence then gives the magnitude of the load. Gravity anomalies in the southern peninsula of Michigan further restrain the dimensions of the load. We propose a model for the formation of the Michigan Basin involving mantle diapirs. We suggest that the first stage in its evolution was diapiric penetration of the lithosphere by hot asthenospheric mantle rock to the vicinity of the Moho. The heating of the lower crust by these hot rocks caused the transformation of lower crust, meta-stable gabbroic rocks to eclogite. Initially the lighter mantle rocks nearly balanced the heavier eclogite. As the mantle rocks cooled by conduction, the basin subsided under the load of the eclogite. The thermal contraction mechanism is supported by evidence that the flexural rigidity of the lithosphere increases with time. This is the effect of thickening of the elastic lithosphere as cooling progresses. 相似文献
12.
《International Geology Review》2012,54(5):578-587
The Tuak and Sudak anticlinoria located upon the eastern periclinal closure of the Crimean meganticlinorium are complicated by a folding of the higher order. According to their size and morphological structures, the folds are subdivided into several types. The small linear disharmonic folds in the Upper Triassic, Lower- and Middle Jurassic deposits within the cores of the above anticlinoria are followed by an elongated brachy-folding within the Upper Jurassic deposits upon the saddle of the Sudak-Yanyshar anticlinorium. The distribution of individual folding types corresponds to the history of fold formation. It depends on the tectonic movement environments, the physical properties of the rocks and other causes. The study of conditions controlling the formation and development of structural forms is conducted on the basis of a structural-facies method. The increase of sedimentation thicknesses and the replacement of coarse terrigenous materials by finer sediments towards the axial parts of the synclines, are evidence of the fact that the folding development was contemporaneous with sedimentation during a prolonged period. Folding, however, proceeded at irregular times. The linear folding within the Tavridian shales upon the saddle of the Tuak anticlinal zone developed under conditions of active positive movements during pre-Bajocian stage of folding. In addition to linear folds, elongated brachysynclines appeared within the areno-argillaceous deposits upon the saddle of the Sudak-Yanyshar anticlinal zone during pre-Oxfordian time. A further growth and isolation of individual folds took place in an environment of considerable tectonic movement intensification during the Oxfordian and Kimmeridgian stages. The most energetic folding movements took place during the pre-Tithonian phase of folding. A sharp uplift of the eastern part of the Sudak- Yanyshar anticlinorium saddle called forth the appearance of crescentic, elongated folds. Within the Meganom downwarping folds developed during the Jurassic under conditions of continuous plunging. The development of the principal structural units is connected with manifestations of deep-seated tectonic processes. The folding located upon the Sudak-Yanyshar anticlinorium saddle is classified as forced folds. The prolonged growth of the folds was accompanied by a forcing up of argillaceous materials into the anticline saddles. The plastic shift of Middle Jurassic clays from under the subsiding synclines toward the continuously eroding anticline saddles, i. e. towards areas of free material outflow, took place under conditions of continuous intensification of the tectonic movement and a continuous increase of load upon the subsiding areas. The supply of plastic material into the anticline saddles began during the Oxfordian stage and continued up to the present. This process proceeds in an environment of further expansion of the Sudak-Yanyshar anticlinorium. In connection, however, with a general weakening of the tectonic movements and an increase of the argillaceous material metamorphization the forcing up of the latter gradually subsides.—Auth.English summ. 相似文献
13.
青藏高原北缘晚新生代的差异性隆起特征 总被引：8，自引：0，他引：8
在青藏高原的研究中,一个涉及高原隆升过程和机理的重要科学问题就是高原差异性隆升问题。文中初步研究了晚新生代以来青藏高原北缘的这种差异性隆升特征。研究表明,高原北缘山系隆升变化的差异性是很明显的。自23.7 Ma以来西昆仑山、阿尔金山和祁连山平均剥蚀率分别有4次阶梯式、谷—峰—谷—峰—谷式和二次阶梯式的变化形式。在3.6 Ma BP以前,青藏高原北缘山系的差异性隆升总体上呈现出东高西低的地貌特征;在3.6～1.7 Ma青藏运动发生期间,高原北缘山系的差异性隆升特征是西强东弱;在0.6 Ma以来,高原北缘山系的隆升差异性呈现出西强—中弱—东次强的特征。自1.7 Ma以来青藏高原北缘西昆仑山褶皱带平均缩短应变为38％,阿尔金山褶皱带平均缩短应变为8％,祁连山褶皱带平均缩短应变为15％。这和它们的高度在此期间的差异特征极为相似。 相似文献
14.
Two-time and two-point (two-particle) correlations are calculated for several parameters of the stellar motions, the densities, and the phase densities of model open clusters, in the vicinities of the cluster stars. The correlation times and correlation radii are determined in spaces of the parameters considered. The distributions of the two-point correlations for the distances between stars in the coordinate and velocity spaces of the stars are calculated. The local maxima of these distributions are used to determine the parameters of density waves, the potential, and the phase density in the model clusters. Analysis of the fine structure of regions of concentration in the two-point correlations in space of mutual distances between stars suggests the formation of polarization clouds near a number of such distances between stars. The distributions of the phase-density correlations are calculated, and the dynamics of these distributions analyzed. The dispersions of these distributions depend strongly on the presence of broad ??wings?? in the distributions (i.e., of strong correlations in the system). These dispersions are considered as a measure of the degree of correlation of phase-density fluctuations in model clusters. A growth in the correlations with time is observed for 50% of the cluster models considered. Flows of the phase-density correlations are investigated. A dominant correlation flow from the region of strong to the region of weak correlations is identified, leading to a flow of kinetic energy toward the cluster center. The rate at which this flow heats the model cluster core is estimated. Signs of weak turbulence are detected in the stellar motions in the model cluster cores with the highest degree of non-stationary in the regular field. 相似文献
15.
作为具有大跨度、超浅埋等特点的千年古地下洞室群,龙游石窟吸引着众多前来研究的岩石力学家和工程地质学家。近些年来,龙游石窟的3号洞顶板多处出现了开裂和离层。安装在3-1号岩柱周围起支撑洞室作用钢柱上的应变片数值也发生了变化。据分析,这些现象出现的一个重要原因是3-2号岩柱强度降低引起洞室围岩受力条件的改变。利用FLAC3D数值软件,借鉴强度折减法,对3-2号岩柱强度降低引起上述变化的情况进行了模拟。数值模拟的结果可以较好地解释上述现象。在此基础上,进一步对3号洞顶板和其他岩柱的应力变化等进行了数值分析。结果表明:①3-2号岩柱的强度已有所下降,并有继续降低的趋势;②随着3-2号岩柱强度的降低,顶板的裂缝将不断增长、增多。其结果可为3-2号岩柱强度降低过程中洞室围岩力学行为的科学分析、预测及石窟的保护等提供依据。 相似文献
16.
《Russian Geology and Geophysics》2014,55(12):1429-1440
We present new data on the structure of deep horizons of the sedimentary cover of the South Kara syneclise, based on an integrated interpretation of data from modern seismic prospecting and data on the geologic structure of the adjacent folded areas. A network of seismic base profiles reprocessed with up-to-date programs is used to determine the structure of the wave fields of the pre-Jurassic sediments of the South Kara syneclise. The interpretation of the wave fields with the use of the network of seismic base profiles shows that the wave fields of the Pai-Khoi-Novaya Zemlya monoclise and the Novaya Zemlya-Taimyr terrace are fundamentally different from those of the South Kara central area of depressions and uplifts. We substantiate a new structural and tectonic zonation of the northern West Siberian Plate, with areas of Hercynian and Early Cimmerian consolidation. The geologic evolution of the South Kara syneclise and adjacent areas in the Late Paleozoic-Early Jurassic is considered. The studies show that the Hercynides of the northern Taimyr Peninsula occupy the deepest central part of the South Kara syneclise, including the North Siberian step. They are separated from the coeval sediments of the surface part of the northern West Siberian Plate by the Early Cimmerian folded area of the Yamal-Pai-Khoi saddle, which joins the Early Cimmerian West Taimyr folded area to the Early Cimmerides of Pai-Khoi and Novaya Zemlya.The Permo-Triassic rifts distinguished in central West Siberia have no shelf extension. Areal structural studies along the surface of the acoustic basement and analysis of wave fields showed that the structures of the South Kara syneclise were semiconcentric and concentric intermontane depressions and troughs in the Permian and Lower-Middle Triassic. They formed at the orogenic stage of evolution of the Hercynides. In the Devonian-Carboniferous, the South Kara syneclise was an intracontinental block structure. It is presumed that elevated blocks consist of carbonate sediments, whereas the separating troughs consist of bathyal terrigenous sediments. The Hercynian folding, which affected mainly deep-water sediment complexes, was followed by an inversion of the troughs, their uplifting and disintegration. The intermontane depressions which formed instead of carbonate shelf in the Permian were filled with sediments from the uplifts which formed instead of the troughs.A well-grounded conclusion is made about the hydrocarbon potential of the pre-Jurassic basement of the South Kara syneclise. The layered seismic record of the pre-Jurassic sediments suggests their heterogeneous composition, i.e., the presence of sand and clay series (reservoirs and caps). The pools might be of the arch-bedded and lithologic (traps which formed in the case of the toplap of beds onto the eroded surface) types or be localized along the line of pinching-out of the Triassic sediments. The largest number of Paleozoic structures is concentrated on the Rogozinskii and Vilkitsky arches, in the Monskaya and Matusevich saddles, and in the northern Rusanov-Skuratov arch.© 2014, V.S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved. 相似文献
17.
V. M. Danilov 《Astronomy Reports》2011,55(6):473-486
The kinematics of stars in open-cluster models are investigated. The central regions of these model clusters are fairly “cool,
” leading to gravitational instability in the cluster cores. A temporary virilization is observed in the model clusters, during
which an appreciable fraction of the fluctuation energy of the cluster is temporarily transformed into the kinetic energy
of the peculiar motions of stars. The duration of this stage can reach ∼108 yr. The origins of this temporary virialization of the model clusters are discussed. The instability of the intrinsic fluctuations
of the phase density in the centers of six clusters and model clusters is investigated. Several new regions of unstable phase-density
fluctuations are found, in addition to those already known. The observed and model clusters can move toward a stable equilibrium
state when the density of the cluster core both decreases and increases. The structure of regions of instability of the phase-density
fluctuations in the centers of the six clusters is studied. Resonance curves for the amplitudes of steady-state phase-density
fluctuations in the center of NGC 6705 are constructed. Analysis of the structure of the regions of instability indicates
an appreciable rate of fluctuation-energy loss due to relaxation effects. The instability increments and widths of regions
of instability fall off with increasing distance of the cluster from the Galactic center. An important role in the formation
of regions of instability may be played by resonances between the frequency of the orbital motion of the cluster in the Galaxy
and the frequencies of intrinsic phase-density fluctuations in the centers of the clusters considered. 相似文献
18.
在软基处理工程中,经常出现竖井打设变密而地基固结效率降低的现象。鉴于此,建立了重叠涂抹区内土体水平向渗透系数的分布函数,给出了涂抹区重叠时竖井地基超静孔压和平均固结度的解析解。通过分析不同工况下竖井地基固结度随竖井间距的变化情况,探究了竖井间距减小而地基固结效率不增反减的成因。最后,探讨了涂抹作用和井阻作用对竖井最小临界间距的影响。结果表明：相邻竖井涂抹区重叠是竖井地基中出现竖井最小临界间距的根本原因。涂抹作用越大,则竖井最小临界间距越大;具体表现为当地基扰动程度增大时或涂抹区半径增大时,竖井最小临界间距随之增大。井阻作用越大,则竖井最小临界间距越小;具体表现为当竖井渗透系数减小时、竖井长度增大时或竖井半径减小时,竖井最小临界间距随之减小。 相似文献
19.
20.
广西红黏土分布区柴油泄漏对土体造成了一定程度污染,为研究轻质非水相非极性柴油孔隙液对红黏土力学性质的影响,本文以0#柴油为添加剂对其重塑样进行不排水快速直剪试验,测得了不同含水率、含油率、法向压力下红黏土抗剪强度及其参数变化规律。研究结果表明:在土-水-油系统中,非极性柴油孔隙液对红黏土强度影响相对较小,且受含水率影响。同一含油率时,红黏土抗剪强度、内摩擦角、黏聚力均随含水率增加而降低;同一含水率时,法向压力影响柴油作用模式,随含油率增加,抗剪强度参数变化较为复杂,当含水率为20%,红黏土内摩擦角、黏聚力反向波动变化;同一含湿率时,柴油比例的提高导致红黏土抗剪强度参数的增大。扫描电镜观察发现,非极性柴油孔隙液的介入,改变了水-土系统的静电及结构模式,导致红黏土强度发生变化,通过所建的“多尺度多阶段柴油作用微结构模型”,阐明了柴油孔隙液对红黏土强度特性影响的微观机理。 相似文献