共查询到20条相似文献，搜索用时 62 毫秒
1.
依据构造控矿为成矿主因、矿源层是物质基础,将五台山绿岩带金矿划分为3种主要类型:与次级褶皱有关的条带状铁建造型金矿床、与剪切变形有关的变质中酸性火山沉积岩型金矿床、与剪切变形有关的变质砾岩型金矿床.这些不同类型的金矿床构造控矿特征明显.五台山绿岩带的区域性倒转复式向斜构造制约了含矿带呈NEE向展布,大型紧闭褶皱转折端控制了矿床的定位,与紧闭褶皱伴生的剪切变形及次级褶皱控制着矿体的规模、形态和产状,剪切裂隙控制着金矿脉的分布和金矿化的局部富集.紧闭褶皱倒转翼部(近转折端)的剪切变形是五台山绿岩带金矿构造控矿的普遍规律.矿源层是物质基础,而经历了紧闭褶皱及伴生的剪切变形带叠加改造的矿源层才是最佳的成矿和找矿靶区.文章以构造控矿理论为指导,重点剖析了典型矿床的构造控矿特征,深入探讨了控矿构造对矿床定位、规模大小、矿体形态、富集程度的制约,认为褶皱与剪切变形不仅在于控矿,而且其本身就是一种重要的成矿作用,进而总结了五台山绿岩带金矿构造控矿的普遍规律. 相似文献
2.
3.
4.
滩间山金矿田控矿构造特征 总被引：1，自引：0，他引：1
本文首次研究了滩间山金矿田控矿构造特征。笔者认为含碳堇青石白云母石英糜棱片岩之中的控矿构造在加里东期韧性剪切带基础上发育而成；华力西期，闪长玢岩和煌斑岩脉与糜棱片岩接触部位控矿构造生成，并同上述糜棱岩之中的控矿构造一起经历了韧脆性剪切作用；印支运动之后，控矿构造演化为脆性断裂。金矿的形成富集与控矿构造多期（次）活动密切相关。华力西期韧脆性剪切作用则做出了突出贡献。闪长玢岩、煌斑岩脉接触带韧脆性变形 相似文献
5.
峪金矿床是小秦岭金矿带内一大型金矿床，属韧—脆性叠加剪切带石英脉型金矿，构造是其首要控矿因素。早期韧性剪切带只对矿脉起宏观控制作用。晚期的脆性断裂为含金石英脉的直接控矿构造。成矿期脆性断裂的多次继承性活动分别控制了热液期4个成矿阶段。脆性断裂形成的空间形态对矿体形态产状具控制作用。有利的矿化富集部位为：①显示压扭性质的近东西向断裂沿走向产状变化处，沿倾向由陡变缓处，断裂面的凹凸转变处；②断裂分支复合部位；③成矿期断裂多次脉动的启张部位；④成矿期断裂构造继承性活动强的部位等。在构造控矿研究的基础上，结合前人部分研究成果。构建了该矿床构造控矿模式。 相似文献
6.
金窝子金矿田位于新甘交界的哈密地区,是北山地区最为重要的金矿田之一,其大地构造背景处于哈萨克斯坦—准噶尔板块与塔里木板块交汇部位东北缘的北山裂谷;断裂构造是矿田内最为重要的控矿因素.文章对矿田内主要的控矿断裂构造特征和断裂构造控矿规律特征进行了研究,F210韧脆性剪切断裂带为矿田内的主干断裂,该断裂的逆冲破碎带为210金矿床的直接控矿构造,控制了蚀变岩型金矿化的发育,由逆冲剪切产生的叠瓦式逆断层不含矿,而近SN向缓倾斜构造控制了210金矿床石英脉型矿化的发育:由F210韧脆性剪切断裂逆冲作用在金窝子岩体内形成的近SN向高角度追踪张性断裂控制了金窝子金矿床石英脉型矿体的形态、产状及成矿元素的分布;在对构造控矿作用研究的基础上,建立了矿区的控矿构造格架. 相似文献
7.
8.
本文主要对小秦岭金矿带的主要构造特征及其控矿意义进行探讨。小秦岭金矿带位于秦岭东西向复杂构造带东段北缘,是一个严格受构造控制而又具有层控意义的变质热液型脉金矿。它严格地受控于大月坪－金罗班复背斜及其衍生的构造之中,因此金矿床的位置及矿体走向与其关系密切。导矿构造为复背斜及其衍生的构造之中,因此金矿床的位置及矿体走向与其关系密切。导矿构造为复背斜两侧较大的韧性剪切断裂和南、北缘走向大断裂（剪切边界断 相似文献
9.
益阳岩金矿床的勘查研究表明，该区含金石英脉均受剪切片理化带控制。构造剪切作用形成塑性变形褶皱和糜棱岩化，并使早期石英脉发生塑性变形或脆性碎裂，为成矿提供了构造空间。随着剪切作用的持续进行，派生了里德尔共轭裂隙，再次为金矿化提供了容矿空间。含矿溶液沿裂隙充填或胶结后期糖粒状石英，形成特殊的合会剪切带型金矿。因此，本文提出在北东一近东西向雪峰孤形构造带找金时，应视剪切片理化带为重点靶区，４１８队在硐坡矿段的金矿预测与验证说明，这一认识具有指导意义。 相似文献
10.
上成金矿位于张八岭构造带北部,是受断裂构造控制的岩浆热液型金矿。通过研究厘定出一条近SN向断裂破碎带—其为管店-龙王尖断裂的北段分支管店-下马断裂—以及F1、F2、F3三条近NW向顺层滑动断裂。石英脉型金矿化受近NW向的顺层滑动断裂构造控制,矿体空间展布上具有平行似等距特征,蚀变岩型金矿化受近SN向断裂破碎带控制。上成金矿床2种不同金矿化类型是同一成矿作用在不同性质的控矿断裂构造下的具体表现,空间结构具有上部石英脉型金矿化下部蚀变岩型金矿化的关系。断裂构造产状变化部位有利于形成矿化弱的厚矿体,反映断裂构造局部地段的高引张空间有利于形成第Ⅰ阶段厚石英脉;而矿脉的分支复合、膨大缩小部位有利于矿化富集,反映断裂构造多期活动强烈地段则有利于Ⅱ、Ⅲ阶段矿化叠加富集。矿化的局部富集与矿体的厚度具有一定的负相关性。结合矿化特征、构造控矿规律总结分析,对上成金矿床深部和外围进行了成矿预测。 相似文献
11.
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
12.
13.
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
14.
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
15.
16.
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
17.
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
18.
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
19.
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
20.
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