首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 48 毫秒
1.
在矿区水文地质勘探工作中,有时会遇到这样的问题:当已有两个含水层的分层水位资料及混合抽水试验资料(包括混合静止水位),如何分别计算两个含水层的渗透系数呢?现在我们就此问题进行讨论。  相似文献   

2.
前言水文地质工作的主要任务之一是测定岩石渗透系数,在多层状含水层中,该项任务主要通过钻孔分层抽水试验来完成。如所周知,分层抽水试验需要大口径钻孔,并对所揭穿的几个含水层分别进行止水隔离,或者对每个含水层单独打钻孔,进行所谓排孔抽水试验,这些方法不仅影响钻探工作进度,且需要大量的管材。排孔抽水试验虽然可以简化钻孔结构,但仍需止水,而且往往使钻探工作量增加一倍以上,耗费很大。  相似文献   

3.
《地下水》2016,(3)
在煤炭资源的勘探和采掘过程中,必须查明对煤层开采有充水意义的含水层(体)的分布特征及富水性,因此,对各充水含水层进行分层抽水试验具有十分重要的意义。以白水煤矿检4井筒检查孔抽水实验为例,采用改进的分层抽水试验技术,获取不同含水层的水文地质参数和水质情况,旨在一个水文地质钻孔中了解不同深度含水层组的水文地质特征,以达到减少施工钻孔、缩短施工工期、节约施工费用的目的。  相似文献   

4.
《地下水》2017,(6)
作为江西主要铁矿富集地之一的新余铁矿田,自20世纪50年代至今,陆续开展多次地质勘查工作,进行了大量的钻孔抽水及少量注水试验。通过对8个矿区37个钻孔和2个浅井抽(注)水试验数据进行分类统计,并针对各含水层试验成果数据进行分析,对铁矿田各含水层的富水性进行了总体评价,结果显示:钻孔单位涌水量普遍小于0.1 L/s·m,总体属弱富水性,仅杨家桥矿区3个钻孔的单位涌水量在0.1~1.0 L/s·m之间,属中等富水性[15],总体水文地质条件简单,利用抽水资料结合稳定流抽水渗透系数计算公式获得的各含水层渗透系数,是矿田矿坑涌水量预测的一个重要参数,该项研究成果可以对区域内邻近矿区的水文地质评价工作提供数据支撑。  相似文献   

5.
一当某地存在着二个以上的彼此隔离良好的含水层时,为了分别求出各个含水层的渗透系数,需要进行分层抽水试验。分层抽水试验要求在上部含水层的抽水工作完成之后,对上部含水层进行止水,以便能够单独地对下部含水层进行抽水试验。在某些情况下,为了节省管材和止水时间,不单独对各个含水层分别进行抽水试验,而对所有含水层共同进行所谓“混合抽水试验”。这种混合抽水试验只能求得全套地层的加权平均的渗透系数。  相似文献   

6.
《地下水》2017,(3)
水文地质参数是研究地下水运动的重要参数,抽水试验是获取水文地质有关参数的一种重要方法。本文以五彩湾矿区一号矿井地下水为研究对象,在分析区域水文地质条件资料的基础上,进行了7组单孔稳定流抽水试验。研究结果表明:对具有供水意义的第四系松散岩类孔隙含水层渗透系数为0.13~2.85 m/d,新近系碎屑岩类裂隙孔隙含水层渗透系数为0.07~0.316 m/d,白垩系碎屑岩类裂隙孔隙含水层渗透系数为0.02 m/d,侏罗系碎屑岩类裂隙孔隙含水层渗透系数为0.009~0.034 m/d。本次实验结果与对比收集资料结果完全一致。  相似文献   

7.
李霞  文章  梁杏  马腾  陈晨 《地球科学》2017,42(5):743-750
含水层的水文地质参数是进行地下水资源计算、地下水污染防控等所必需的基础数据,结合数值模拟技术进行含水层参数反演很有必要.按照1:5万水文地质调查规范在江汉平原仙桃市杨林尾镇复兴水厂不同含水层位开展抽水试验,包括深层含水层单孔抽水试验以及浅层含水层中群孔(2孔)抽水试验.对于单孔抽水试验,应用第1类越流系统井流理论进行参数反演;对于群孔抽水试验,推导了特定综合井函数,并利用特定标准曲线匹配法和直线图解法求解了含水层参数.随后利用FEFLOW软件建立了相应数值模型,拟合了含水层参数.结果表明:浅层含水层的渗透系数变化范围为21.66~54.00 m/d,贮水率变化范围为1.28×10-5~8.00×10-4 m-1;深层含水层渗透系数变化范围为1.27~7.00 m/d,贮水率变化范围为3.90×10-6~5.00×10-6 m-1.对于深层承压含水层而言,越流补给量较大.采用数值模拟方法结合抽水试验数据求参,综合考虑了含水层结构,拟合效果好,所得结果更加可靠.   相似文献   

8.
煤田水文地质勘探钻孔,即是取煤、岩芯孔又是水文地质孔;而且一个钻孔中最少作两层抽水试验。因此,分隔上下含水层是不可缺少的工作之一。根据水文地质条件,选择止水材料与止水方法是抽水试验的关键。为此在实际工作中改进止水方法和选择最佳止水材料是保证抽水试验成功的先决条件。多年施工中采用变径管靴止水,得到良好效果和可喜的经济效益。  相似文献   

9.
新型地下水流速流向测量技术及其在岩溶区调查中的应用   总被引:1,自引:0,他引:1  
我国南方岩溶区往往水文地质条件复杂,含水层的渗透性具有较强的非均一性。为探究岩溶含水层矢量渗透系数的分布规律,识别多级次岩溶水流系统的特征,利用新型地下水流速流向测量技术,在鄂西香溪河流域的典型水文地质钻孔进行了试验研究。结合地面调查、抽水试验和压水试验等方法,对流速流向测试与分析结果进行了水文地质解释及探讨。结果表明:所选典型钻孔岩溶含水层的垂向渗透系数不均一性较强,新型流速流向测量方法计算得出的渗透系数与抽水试验的计算结果相差5%;与压水试验相比,在钻孔2个不同深度的含水段,2种方法计算的渗透系数分别相差44%和2%;不同深度的地下水流向测量结果表明,钻孔在垂向上揭示了2个不同层次的岩溶水流系统。新型地下水流速流向测量与分析方法能够较准确地识别岩溶水的优势径流方向和径流层位,对于岩溶含水层渗透性非均一性的定量刻画具有良好的应用前景。  相似文献   

10.
为了减少因分层抽水而造成的钻探施工过程中的困难,长期以来水文地质工作者在探讨用混合抽水试验确定含水层水文地质参数的方法。在已有的方法中,多采用稳定流混合抽水试验加做某些辅助工作的办法,以确定含水层水文地质参数。但由于稳定流抽水试验本身在理论上的缺陷,尤其是因为有的方法需要  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.
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  
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   

17.
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   

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 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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号