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1.
国际喀喇昆仑公路沿线巴托拉冰川变化预测的验证   总被引:1,自引:1,他引:1  
张祥松  王文颖 《冰川冻土》1996,18(2):97-103
1974-1975年国际喀喇昆仑公路巴托拉冰川考察组,在预报巴托拉冰川到本世纪90年代的前进值和下世纪的变化趋势指出、巴托拉冰种60年代开妈的前进不会危害国际喀喇昆仑公路、桥梁;冰下排水道相当长时间稳定不变;公路与拟选桥位下存在埋藏冰川冰及最大洪水主充量值等科学论断。  相似文献   

2.
·书刊介绍·     
这是一部系统全面研究喀喇昆仑山巴托拉冰川的专门性科学专集。巴托拉冰川系世界中低纬度山区长度超过50公里的八大冰川之一,影响著名的中巴公路交通。中国科学院兰州冰川冻土研究所派出的、由施雅风教授等同志组成的冰川考察组,于1974、1975年对该冰川进行了详细考察。本书以专题形式总结了这次考察的成果,全书十六个章节,四十万宇,分别论述了有关巴托拉冰川及其邻近地区冰川的生成、发育、历史演变、冰川动态、运动、消融以及冰川水文、气候等特征;进行了冰川区地面立体摄影测量,制就一幅1:60000彩色巴托拉冰川图;计算了冰川融水的最大流量;预报了本世纪内冰川的  相似文献   

3.
巴托拉冰川考察组在1974—1975年对巴托拉冰川进行了全面系统的考察,用波动冰量平衡法和冰川末端运动速度递减率,对巴托拉冰川末端未来的变化,作了定量的预测:巴托拉冰川处于前进时期,冰川末端将继续前进180—240米左右,每年平均前进11米,前进年限为16—22年左右,到1991—1997年间,此时冰川最终达到平衡,而终止前进;  相似文献   

4.
喀喇昆仑山巴托拉冰川水文的特征大部已在“巴托拉冰川融水径流的基本特征”,一文中进行了论述。本文仅就它未提及的和研究不够深入的某些水文特征进行探讨,作为上述论文的补充。  相似文献   

5.
施雅风 《冰川冻土》2003,25(4):479-481
1974年初,外经部、交通部和总后勤部联合给中国科学院兰州冰川冻土沙漠研究所(现为中国科学院寒区旱区环境与工程研究所)下达任务,要求派冰川考察组对影响中(国)巴(基斯坦)公路建设的巴境内喀喇昆仑山区巴托拉冰川考察,以二年时间摸清该冰川的运动变化特征,提出中巴公路通过方案.  相似文献   

6.
冰川末端动态的预报,通常采用统计分析〔1〕和数学—物理〔2〕两种方法。后者利用波动—扩散方程,运动—流变方程或其二者的变种为泛定方程,再根据各冰川的具体条件,给出完整的数学模式,进行数值预报。 笔者在以往提出的“波动冰量平衡”预报方法〔3〕的基础上,探讨了山岳冰川一个新的预报模式。以冰川基本运动方程,和有限区段的冰川变化特征建立定解问题,并阐明了定解条件确定的原则。最后,在国产DJS-130小型计算机上,运用Lax格式,对喀喇昆仑山巴托拉冰川末端动态,进行了数值解求取和影响因素分析。  相似文献   

7.
第1期我国多年冻土的主要特征……………………………………………………………用幼吾郭东信(1)我国冰川的温度……………………………………………………………黄茂桓王仲祥任贾文(20)论冰川擦痕………………………………………………………………………………………李吉均(29)巴托拉冰川末端动态数值预报……………………………………………施雅风丁德文付连弟(35)青南藏北高原多年冻土的形成及发展趋势探讨……………………………………樊溶河姚尚生(45)大兴安岭地区给水管道电热防冻试验及其应用……………………………………何杰郑启浦…  相似文献   

8.
近期气候变暖念青唐古拉山拉弄冰川处于退缩状态   总被引:15,自引:8,他引:7  
1999和2003年在念青唐古拉山冰川考察期间,采用GPS对拉弄冰川末端位置进行了测量,并将将测量结果与1970年航摄冰川末端位置进行对比分析.结果表明:1970-1999年拉弄冰川末端退缩了285m,平均年退缩量9.8m;1999-2003年拉弄冰川退缩13m,平均年退缩量3.25m.由于冰川对气候的响应有一定滞后性,近年来气候持续变暖将使拉弄冰川继续保持退缩状态.  相似文献   

9.
俄罗斯图瓦共和国境内的蒙贡-台加山是位于亚洲中心的一个独立的冰川作用中心。现代冰川共36条,总面积27.8km2,主要受西风环流及地方性环流的降水补给,具有亚大陆型冰川的特征。小冰期最盛期以来,冰川面积减少49.3%。近150年来,冰川面积和长度继续减少,末端及雪线高度升高。近30年来,冰川退缩速度加快,冰川物质平衡有10年左右的波动变化,目前处于负平衡状态。但1992-1993年两条山谷冰川突然前进。对比亚洲中部其它山系,发现本区冰川动态变化独特,说明不同地区冰川对于全球性气候的响应过程比较复杂。  相似文献   

10.
青藏高原各拉丹冬地区冰川变化的遥感监测   总被引:49,自引:20,他引:49  
以位于青藏高原长江源头的各拉丹冬地区冰川为例, 利用2000年的TM数字遥感影像资料、 1969年的航空相片遥感资料、地形图及数字地形模型, 通过遥感图像处理和分析提取研究区小冰期最盛期(LIA)、 1969年和2000年的冰川范围, 并在地理信息系统技术支持下分析该地区冰川的进退情况. 研究结果表明, 该地区1969年冰川面积比小冰期最盛期的冰川面积减少了5.2%, 2000年的冰川面积比1969年的冰川面积减少了1.7%. 从1969年到2000年最大冰川退缩速度为-41.5 m*a-1, 最大冰川前进速度为+21.9 m*a-1. 本区的冰川基本处于稳定状态, 冰川退缩的速度不是太大, 并有前进的冰川存在.  相似文献   

11.
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.
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.
从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返   总被引:4,自引:1,他引:4       下载免费PDF全文
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   

16.
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   

17.
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  
陈银生 《世界地质》1999,18(1):54-59
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   

18.
19.
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   

20.
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.  相似文献   

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