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对溪洛渡水电站坝址温度场330m和360m高程平切温度等值线图中高温区展布形态和渗流场360m高程至下伏灰岩顶板平均吕荣（Lu)值等值线图中高值区展布形态进行了对比研究，认为二者在分布形态、延展方向及高温－高值点位置都极其相近，其原因是由该区特定的地热水文地质条件决定的；并认为在具有如溪洛渡坝址这样类似地热水文地质条件的地区，可以通过对地热温度场的研究，从另一侧面来论证同一区内岩层渗透性分布特性；利用温度场效应亦可对渗流场参数进行验证研究，以用于水利水电工程设计。 相似文献
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马湖峪河属黄土丘陵沟壑区,近年来由于流域上游修建多座淤地坝以及水土保持工作的进行,使得河流地形地貌,下垫面、植被等诸多因素发生变化。本次通过对降雨径流关系分析计算,推算出新的汇流参数m值,出并点汇计算结果 m与Qm与流域面积F之比的关系曲线,通过点群中心线作为标准线,得到汇流参数m随Qm与流域面积F之比的加大而趋于稳定,求得该站新的m值为9.8,为该流域推理公式法计算暴雨洪水提供技术依据。 相似文献
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整套重力计算程序包括了除“地改”以外的所有项目的计算，在这篇文章中我们先仅介绍了“测区参数初始化”及“基点网联测”(采用三程小循环方式)的计算方法。“测区参数初始化”功能可生成gdw．csh初始化文件(该套程序的各项功能都要读取该文件中的相关参量)；“基点网联测”功能可计算基点网联测的各项精度，对联测进行平差，求出各分基点绝对重力值。 相似文献
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《地下水》2016,(4)
地温梯度和大地热流值特征是研究盆地地热地质特征的重要参数。本文通过对南阳盆地6眼浅层测温井及8眼地热井进行实地温度测量,分析研究了南阳盆地浅层地温场特征和地温梯度。分析结果表明南阳盆地浅层地温梯度为3.4℃/100m,恒温带深度为30m,恒温带温度为16.6℃,地热井地温梯度平均值为2.4℃/100m。同时对地热井岩石热导率进行了测试,测试结果表明南阳盆地岩石导热率值平均值2.623W/m K,从而计算出地热田平均大地热流值为63.0 m W/m~2(1.51 HFU),略高于地球表面平均热流量(1.2~1.4 HFU)。在可及深度内(以3000 m深度为准),不具有高温地热资源形成的条件,属低温(25℃~90℃)地热资源。 相似文献
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基于v-SVR和GA的初始地应力场位移反分析方法研究 总被引：5，自引：3，他引：5
基于一种改进的支持向量机（v-SVR）和改进的遗传算法（GA），提出一种初始地应力场位移反分析方法。该方法通过正交设计方法安排较少次数的正分析方案，用v-SVR对正分析中测点位移值与参数构成的样本集进行学习，建立参数取值与观测点测值的非线性隐式方程；采用确定性或随机反分析的思路确定反分析的优化目标函数，并利用GA搜索最优参数取值。采用v-SVR方法建立的参数取值与位移量测点测值的非线性隐式方程，能够以很高的精度拟合和预测不同参数取值时的观测点测值，因此，可以用该隐式方程代替正分析，减少计算量；采用改进的GA方法能够准确搜索到最优参数；搜索到的最优参数值与理论值相当吻合。算例表明，基于v-SVR和GA的初始地应力场位移反分析方法是一种行之有效的初始地应力场位移反分析方法，可以广泛用于初始地应力场确定性反分析和随机反分析。 相似文献
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基于流溪河模型构建了不同空间分辨率的新丰江水库入库洪水预报模型,采用粒子群算法优选模型参数进行洪水模拟,对比实测资料验证了模型性能。结果表明,建立的新丰江水库入库洪水预报流溪河模型模拟效果优良,符合新丰江水库入库洪水预报的精度要求,可用于新丰江水库入库洪水预报：90 m空间分辨率的模型模拟效果最好,200 m空间分辨率的模型也具有良好的模拟性能,500 m空间分辨率的模型模拟性能有明显降低。模型计算工作量随分辨率的提高呈指数增加,90 m空间分辨率的参数优选时间是200 m空间分辨率参数优选时间的7.04倍,而200 m空间分辨率的参数优选时间是500 m空间分辨率参数优选时间的3.53倍。 相似文献
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岩体工程特性研究中弹性波速参数取值方法探讨 总被引：9，自引：0，他引：9
工程岩体的各向异性特征导致了弹性波速的各向异性。因此，在岩体工程特性研究、岩体质量评价等方面，应注意合理地应用岩体弹性波速资料。笔者分析了岩体波速的各向异性特征，并指出：由于波速各向异性的存在，在岩体完整性系数计算中，岩体波速应取不同方向波速的几何平均值。当利用文中所给公式进行岩体孔隙率计算时，建议波速取最小值；在进行节理、裂隙发育的优势方向判断时，则取不同方向的波速值分别进行计算；当计算弹性模量时，必须取与岩体受力方向相一致的波速值。并给出了利用波速进行有关参数计算的实例。 相似文献
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湖南冷水江矿区障壁砂坝—泻湖—潮坪沉积体系泻湖的咸化现象 总被引：1，自引：0，他引：1
以岩石地球化学分析为基础，对测水组含煤质地层进行沉积环境参数计算，恢复沉积介质的古盐度结果表明：滨岸环境的含煤岩系形成中泻湖经历成化阶段，从而补充了以前有关泻湖的演化机制。 相似文献
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Guboglo M. N. 《GeoJournal》1980,4(1):53-58
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen. 相似文献
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Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth
B. P. Kondratyev 《Astronomy Reports》2017,61(8):709-714
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″. 相似文献
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Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated. 相似文献
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位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压，而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩，榴辉岩及其他直接围岩皆呈包体存在于其中，并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体，表明新元古代花岗岩的组成物质也经受过超高压变质作用，且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次（或阶段）却少于榴辉岩。椐上述可得如下推断：超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部（俯冲板块前部）形成的；榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的，其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升，遭受剥蚀。 相似文献
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某高速公路下伏煤矿采空区稳定性分析 总被引：10，自引：0，他引：10
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。 相似文献
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摩擦桩基桩土间极限摩阻力取值问题探讨 总被引：1，自引：0，他引：1
通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。 相似文献
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The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads 总被引：3，自引：1，他引：2
Clemente Irigaray Francisco Lamas Rachid El Hamdouni Tomás Fernández José Chacón 《Natural Hazards》2000,21(1):65-81
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning. 相似文献
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The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time. 相似文献