滇西腾冲麻栗坝钼-铜-铅-锌矿床锆石LA-ICP-MS U-Pb 和辉钼矿Re-Os年龄及其地质意义

麻栗坝钼铜铅锌矿床位于三江特提斯成矿带的西南端,赋矿岩体为黑云母二长花岗岩,属于腾冲花岗岩带古永复式岩体小龙河序列.黑云母二长花岗岩锆石LA-ICP-MS U-Pb年龄为78.6±1.2 Ma,属于燕山晚期,相当于晚白垩世;矿体中辉钼矿的Re-Os等时线年龄为78.5±3.7 Ma,略晚于成岩时间,为本区首次获得的精确成矿年龄.其中,辉钼矿的Re、Os同位素特征表明成矿物质主要来源于地壳.麻栗坝钼铜铅锌矿床成矿年龄、成矿岩体年龄接近,约为78 Ma,与小龙河岩体年龄(79～65 Ma)在误差范围内一致,表明矿床的热液演化活动时间较短,矿化和成岩均发生在岩浆活动的早期阶段.它们同为燕山晚期,是在新特提斯洋渐次东向俯冲过程中地壳加厚重熔引发的岩浆活动与热液作用的产物.     

西藏甲玛铜多金属矿床流体包裹体研究

甲玛铜多金属矿床是西藏冈底斯中段东部的超大型矿床,主要由角岩型铜钼矿体、斑岩型钼铜矿体以及矽卡岩型铜多金属矿体构成.根据矿物组合与脉体穿插关系,将角岩型和斑岩型矿体中各类热液脉体分为成矿早阶段A脉、转换阶段B脉以及成矿晚阶段D脉.A脉包括具有钾长石蚀变晕的石英脉、石英+钾长石±黄铜矿±辉钼矿脉、石英+黑云母脉、黑云母+...     

福建紫金山矿田罗卜岭铜钼矿化斑岩锆石LA-ICP- MS U-Pb年龄及成矿岩浆高氧化特征研究

罗卜岭斑岩铜钼矿床是紫金山Cu-Au-Mo浅成低温-斑岩矿田内新近发现的大型斑岩铜钼矿床,本文在岩芯及光薄片系统观察的基础上,分析了矿化斑岩锆石LA-ICP-MS U-Pb年龄及锆石Ce4/Ce3+比值.罗卜岭赋矿斑岩体可分为两期,早期为角闪黑云母花岗闪长斑岩及黑云母花岗闪长斑岩,晚期为黑云母花岗闪长斑岩.早期角闪黑云母花岗闪长斑岩和黑云母花岗闪长斑岩锆石LA-ICP-MS U-Pb年龄分别为103.7±1.2Ma,MSWD=0.33和103.0±0.9Ma,MSWD=1.00;晚期黑云母花岗闪长斑岩锆石LA-ICP-MS U-Pb年龄为97.6±2.1Ma,MSWD=6.00.罗卜岭成矿斑岩基质普遍发育硬石膏,两期成矿斑岩锆石都具较高的Ce4 +/Ce3平均值,在630 ～770之间,高于区内非成矿花岗岩锆石的Ce4+/Ce3+平均值(182 ～577),显示罗卜岭斑岩矿床成矿岩浆具有高氧逸度的特征.据罗卜岭斑岩矿床的形成时代、高氧逸度岩浆特征,结合华南地区中生代构造背景,我们初步认为罗卜岭斑岩矿床的形成可能和中生代古太平洋向北西西方向俯冲有关.     

西藏玉龙铜矿带包买矿床含矿斑岩锆石U-Pb年代学

包买斑岩型铜钼矿床是西藏玉龙铜矿带北段重要组成部分,具有典型的斑岩型矿化、蚀变特征.最新勘查进展揭示其铜、钼资源量均已达中型矿床规模,但理论研究工作仍十分薄弱.以矿区基本地质特征为基础,运用LA-ICP-MS锆石U-Pb年代学方法,精确获得包买矿区与成矿有关的黑云母花岗岩和黑云母二长花岗岩侵位时代分别为:41.3±0.2 Ma和40.8±0.2 Ma,与玉龙、扎那尕等矿床一致,是始新世印度大陆与欧亚大陆碰撞造山过程的产物.综合区域已有年代学证据,玉龙铜矿带与成矿有关的斑岩体主要集中侵位于37~42 Ma,可能不存在明显的早（51 Ma）、中（41 Ma）、晚（33 Ma）三期,且从北西向南东,成岩成矿时代也没有明显降低变新的趋势.      

乌奴格吐山斑岩铜钼矿床地质特征及成矿模式

乌奴格吐山斑岩铜钼矿床是燕山晚期中酸性岩浆多次活动的产物。矿床的成矿母岩是同源异期多阶段形成的四个二长花岗斑岩小岩体,岩体的直接围岩是燕山早期黑云母花岗岩。矿床形成于斑岩活动晚期。由于富含成矿元素及挥发组分的中高温气液流体,引起斑岩体及其外接触带普遍遭受蚀变而产生多种蚀变类型,它们以斑岩体为中心呈环状分布。铜钼矿体主要赋存于石英绢云母化带,次为钾长石化带。     

滇西北红山铜钼矿床辉钼矿Re-Os同位素测年及其成矿意义

红山铜钼矿床是义敦岛弧南端格咱火山-岩浆弧中已探明规模最大的夕卡岩型铜矿床,近年来在其深部勘探过程中又发现斑岩型铜钼矿体.利用辉钼矿Re-Os同位素测年技术,分别对红山铜钼矿床中5件夕卡岩型矿石和1件斑岩型矿石中辉钼矿进行定年,首次获得红山铜钼矿床高精度成矿年龄.夕卡岩型矿石中辉钼矿Re-Os模式年龄为77.90 ～ 81.05Ma,加权平均值为79.32±0.87Ma,斑岩型矿石中辉钼矿模式年龄为80.71Ma,两者在误差范围内相一致;6件样品辉钼矿等时线年龄为80.0±1.8Ma,代表了红山铜钼矿床的成矿时代.辉钼矿中Re的含量为(4.074±0.035) ×l0-6～(94.21±0.75)×10-6,指示其物质来源以壳源为主,有少量幔源物质混入.红山铜钼矿床与格咱火山-岩浆弧燕山晚期岩浆侵入作用的高峰期及相关斑岩-夕卡岩型多金属矿床的成矿年龄一致,表明它们是弧陆碰撞的后造山伸展背景下同一区域地质事件的产物,该期夕卡岩-斑岩型铜钼多金属具有较大成矿潜力.     

福建紫金山矿田罗卜岭斑岩型铜钼矿床辉钼矿Re-Os定年及地质意义

罗卜岭铜钼矿床是位于紫金山矿田北东侧的一个大型斑岩型铜钼矿床,铜钼矿体产于四方花岗闪长岩和罗卜岭花岗闪长斑岩体内。通过对该矿床11件代表性辉钼矿样品进行Re-Os同位素定年,获得的模式年龄为104.7±1.6～106.5±1.5Ma,等时线年龄为104.9±1.6Ma,与赋矿围岩的成岩年龄一致,表明罗卜岭铜钼矿床形成于早白垩世,属燕山晚期构造-岩浆活动产物。由于斑岩铜钼矿床为紫金山矿田成矿流体早期演化的产物,故认为紫金山矿田成矿流体演化起始于105Ma左右。     

西藏色布塔铜钼矿床中辉钼矿Re-Os定年及其成矿意义

色布塔铜钼矿床位于冈底斯成矿带北部,具有细脉浸染状矿化,围岩蚀变发育等斑岩型铜钼矿床特征.本文使用电感耦合等离子体质谱仪TJA X-series ICP-MS对色布塔铜钼矿床的花岗斑岩中的辉钼矿进行ReOs同位素定年研究,获得了6件样品的模式年龄为87.52±1.35～88.8±1.26Ma,等时线年龄为88.8±1.5Ma.本文研究成果表明,色布塔铜钼矿成矿时代为晚白垩世早期,属燕山期构造-岩浆活动的产物.     

西藏阿浪扎玛铜钨矿床地质特征及控矿因素

阿浪扎玛铜钨矿床属矽卡岩型矿床,主要成矿岩体为燕山晚期黑云母二长花岗岩。铜钨矿体赋存于花岗岩体与中侏罗统马里组灰岩接触带矽卡岩中。     

武夷山成矿带构造-岩浆-成矿作用与演化

本文以武夷山成矿带地质构造演化和岩浆活动为主线,将武夷成矿带分为元古代、古生代和中生代三大成矿期及相应的赋矿地层系统,划分为七个成矿系列:即晋宁裂谷期海底火山喷流型块状硫化物矿床成矿系列;加里东块体拼合期金铜钼矿床成矿系列;海西裂陷扩张期铁铜锰矿床成矿系列;早燕山裂陷扩张期铜银铅锌锑矿床成矿系列;早燕山地壳重熔期钨锡铋钼铌钽和稀土矿床成矿系列;晚燕山底侵伸展期铁铜铅锌矿床成矿系列;晚燕山大陆扩张裂解期铜金银铀矿床成矿系列。根据地质构造演化、岩浆活动,成矿系列和代表性矿床等特征,提出了武夷山成矿带构造-岩浆-成矿作用与演化的事件格架。     

Unity of the national and the international in the socio-cultural development of the peoples of the USSR

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.     

Global repeating events in the history of the Earth and the motion of the Sun in the Galaxy

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.     

Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth

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″.     

从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返

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。     

某高速公路下伏煤矿采空区稳定性分析

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。      

摩擦桩基桩土间极限摩阻力取值问题探讨

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。     

The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads

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.     

Paleomagnetic implications on the evolution of the tethys belt from the atlantic ocean to the pamirs since the triassic

We first re-examined the apparent polar wander curves for stable Eurasia and Africa since the Triassic. These curves were then combined together with curves of North and South America according to the kinematics of the Atlantic ocean and a synthetic polar wander curve was given. Then, most of the paleomagnetic results from the Tethys mobile belt, from the Atlantic to the Pamirs, were analysed.Several groups of plates, microplates and blocks can be seen. First, relatively stable regions like Maghreb and Sicily, which have not moved much. Then we have a group formed by Iberia, Sardinia, Italy and, to a lesser extent, Corsica and the Western and Central Alps. For these blocks, movements are anticlockwise rotations chiefly driven by the anticlockwise rotation of Africa, but they are sometimes stronger.To the east, a major change takes place. The north of the Aegean Sea and the Ionian zone are clockwise rotated and these rotations are recent: Oligocene-Miocene for the first part, Pliocene to the present for the second part.A major problem arises in Turkey, Caucasus and Iran. Paleomagnetic results indicate a position far to the south of Eurasia, and, at the same time, geological evidence is in favour of a position close to Eurasia. We discuss these discrepancies.