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1.
The distribution of selected critical elements in the sedimentary rocks of the Carboniferous coal-bearing series within the Polish Coal Basins is presented.Critical elements such as Be,Mg,Si,P,Sc,V,Co,Y,Nb,In,Sb,La,Ce,Hf,Ta,W,Bi were analysed using inductively-coupled plasma mass spectrometry(ICP/MS).Concentrations of elements such as Sb,Bi,In and,to a slightly lesser extent,Nb,as well as Sc,show average concentrations higher than those from the upper continental crust.The average concentrations of elements like Hf,Mg,P,Y,La,and Ce are slightly lower than in the upper continental crust.Other elements,such as Be,Co,Si,Ta,W and V have average concentrations that are similar,but slightly enriched or slightly depleted,relative to the upper continental crust.The research showed enrichment of some critical elements in the analysed samples,but not high enough that extraction would be economically viable.Statistical methods,which include correlation coefficients between elements and cluster analysis,reveal a strong positive correlation between elements like Be,Bi,Nb,Sc,Ta,W and V.Very high,almost total,positive correlation is also noted between La and Ce.  相似文献   

2.
谭锡畴 《地质论评》1943,8(Z1):41-66
引言易门安宁禄丰三县,为云南中部产铁区域,土炉冶炼,采挖已久,惟关於矿产之价值,矿床之种类,作科学之研究者,至近年来,始有其人,最初有法人来克里者,曾考察易门铁矿,  相似文献   

3.
云南矿产概论   总被引:4,自引:1,他引:3  
谢家荣 《地质论评》1941,6(Z1):1-42
云南矿产向称丰富,中外报告,言之屡矣。自抗战军兴,增加後方生产,为当务之急,于是滇省之地下富源,遂益为国人所重视。经济部地质调查所,西南联大地质系,本省建设厅及经济委员会等先後派员,实地测勘,所得结果俱极重要,惜多散见於分刊物及简报中,尚无概括之论述,足资一般之参考  相似文献   

4.
编者言     
《地质论评》1945,10(Z3)
“地质论评”在中国地质学会困苦的支持下,八年来幸未间断。这是我们的领导当局之苦心,与工作同人之努力,所收的效果。对于学会出版物,黄汲清,尹建猷,谢季骅,李赓阳,王斐轩,及帮助编印诸君,都尽了不少义务。他们求学之专,生活之苦,检讨之严,服务之热,都到了可敬佩的地步。出版  相似文献   

5.
《地质论评》1944,9(Z3):311-312
马以思女士原籍四川成都,先祖以经营金矿,举家迁居於东北边陲,女士於民国八年十月廿五日生於黑龙江,天资聪慧,幼年习日文颇有成就,九一八事变後,父伯严公携眷内迁,  相似文献   

6.
南嶺何在     
李四光 《地质论评》1942,7(6):253-266
长江流域和东西江流域,除了在广西的东北角兴安附近,曾用人工勾通水系而外,可以说是两个完全独立的排水区域,这两个区域的干流,大致成东西向,而在这两个区域之间,也有断断续续的山脉,形成天然的界线,这些山脉或分水岭,普  相似文献   

7.
汤克成  姚瑞开 《地质论评》1941,6(Z2):302-303
攀枝花及倒马坎,位盐边县西南,踞金沙江北岸。攀枝花山势陡峻,距江边约三公里,倒马坎山小坡平,即濒江干。铁矿藏量颇丰,质亦良佳,且密迩永仁煤田,及盐边县属乌拉阿卡坭红果等煤区,洵可大量开采,西南钢铁事业,至有望焉。  相似文献   

8.
关于甘肃及青海境内之第三纪红色地层   总被引:1,自引:0,他引:1  
路兆洽 《地质论评》1948,13(Z2):258-261
一、绪言在甘肃及青海境内,包括祁连山南北,秦岭以北,并六盘山东西地带,第三纪红色地层,颇佔重要地位,惟迄今对其命名,时代,及分层等尚末能一致,兹就著者各处观察所得,并与前人所论比较论证,期能获得进一步之认识。  相似文献   

9.
悼刘莊     
李广源 《地质论评》1944,9(Z1):127-128
刘莊先生字伊璜,山东泰安县人,生於民国八年,双亲早世,赖祖叔抚育成人;颖悟非凡,沈静寡言,乐交游,重情感。十二岁就读泰安省立第三初级中学;十五岁考入山东省立济南高级中学,课馀之暇,喜习纲球,技术甚精。旋於民国廿五  相似文献   

10.
高平 《地质论评》1944,9(Z1):123-126
二十六年冬,余奉调入江西地质调查所工作;时赣北战事紧张,所址迁移萍乡安源镇之葛仙寺,下车伊始,即与刘君辉泗相遇於葛仙寺下之山坡,君方自赣南调查归来,畅谈野外所见,滔滔不绝。及相处日久,尤慕其禀牲真挚,待人诚坦,不  相似文献   

11.
潘卓夫  金亮星  陈文胜 《岩土力学》2016,37(7):2079-2084
边坡非圆弧临界滑动面搜索是边坡稳定性计算中的一个关键问题,其实质是找到一条安全系数最小的滑动路径。采用新的全局最优化算法--径向移动优化算法搜索路径相对其他算法具有快速、存储空间小、计算简单等优势,但却存在搜索结果不稳定的现象,为克服这个问题,对其数据结构进行调整,提出了改进的径向移动算法,使路径搜索趋于稳定。搜索到的滑动面路径对应的安全系数采用不平衡推力法进行计算,在可行性分析的基础上,采用二分法对安全系数快速、精确地求解。通过一个水库岸坡的算例计算,验证了改进的径向移动算法用于非圆弧临界滑动面搜索的有效性。又通过分析对比改进的径向移动优化算法和粒子群算法的搜索结果,展示了改进的径向移动算法快速收敛,稳定性高的显著优势。  相似文献   

12.
简单斜坡油气富集规律——以松辽盆地西部斜坡北段为例   总被引:16,自引:0,他引:16  
斜坡是断陷和凹陷型盆地的重要构造单元,按其断裂发育程度和沉积厚度分为复杂斜坡和简单斜坡。松辽盆地西部斜坡为断裂不发育、平缓的简单斜坡,简单斜坡油气成藏有特殊性,表现在三个方面:一是简单斜坡的原油主要来自临近的凹陷,油气沿砂体以优势路径方式侧向运移,油气呈“线状”分布;二是简单斜坡大规模构造圈闭不发育,圈闭类型以地层、岩性和构造-岩性圈闭为主,其分布受构造带控制,超覆带发育岩性上倾尖灭圈闭,受规模较大的断层控制形成的鼻状构造带上发育断层遮挡和构造-岩性圈闭,不受断层控制的鼻状构造带主要发育构造-岩性圈闭。三是简单斜坡普遍受大气水的淋滤作用,由于游离氧的进入使原油遭受氧化降解作用而稠化,造成简单斜坡稠油分布普遍。这种成藏的特殊性决定了油气富集规律:只有位于油气运移路径上的圈闭才有成藏的可能。简单斜坡油气勘探方向是,在油气运移路径上寻找低幅度构造背景下的岩性油气藏(小规模)、规模较大断层附近寻找断层遮挡油气藏(中等规模)和地层超覆带上寻找岩性上倾尖灭油气藏(大规模)。  相似文献   

13.
溃屈型破坏是一种常见的顺层岩质边坡破坏模式,溃屈变形发展机制及失稳破坏的定量研究对滑坡工程勘查和防治指导十分重要。本文根据边坡的地质环境和力学作用机制,建立了三维受压板简化模型,其能够考虑岩层自身重力、地震力、静水压力的共同作用和岩体材料塑性变形的影响。基于弹塑性受压板稳定理论,利用能量法推导得到了边坡溃屈变形破坏的临界方程。对于溃屈型边坡的结构失稳和滑动失稳分别提出了相应的稳定性判定方法,并针对不同状态的边坡提出了相应的防治措施建议。以四川省甘孜藏族自治州巴塘县下归哇边坡为例,对所提判定方法的正确性进行了验证。计算结果表明,边坡的临界溃屈长度(a1)为483.8 m,说明下归哇边坡能够发生溃屈变形;现场勘查得知边坡实际溃屈长度(a′)为530.0 m,a′>a1,可知边坡是稳定的。这与实际情况相吻合,由此证明本文所提出的判定方法可行。  相似文献   

14.
文章以磨溪气田为例,重点论述氡气异常在石油、天然气勘探中对油藏、气藏边界和油-水或气-水边界的指示效果,通过对该气田测量成果的研究表明:(1)氡气异常在指示和反映断裂构造时,异常强度大、峰值高,且异常分布范围窄,表现出单点或两点突然出现的窄峰区;(2)当油气保存条件好、储量规模大时,氡气异常反映的油-水、汽-水边界峰值适中;(3)当地下水丰富且活跃时,氡气异常强度相对较高,规模较大,油气保存条件一般不好.此项研究成果在石油、天然气勘探中可降低投资成本,值得推广应用.  相似文献   

15.
Data, each consisting of a unit vector and a position, are modeled as a smooth unit vector field plus random directional errors; the smooth unit vector field is estimated by fitting a spline to observations. The estimate is nonlinear; it is obtained with an iterative procedure in which, at each step, a least-squares smoothing spline is fitted to a set of pseudovalues. The resulting estimate is exemplified with a data set extracted from the literature in geology. The proposed estimate is compared, using the same data set with that obtained through suggestions of other authors, and is found to have attractive qualities. The use of plots of the resulting estimate to find the appropriate value of the smoothing parameter is emphasized throughout.  相似文献   

16.
构造应力场研究的新进展   总被引:22,自引:0,他引:22  
万天丰 《地学前缘》1995,2(2):226-235
本文阐明构造应力(主应力与剪应力)方向的研究方法以及最新研究成果,指出全球各地区在某一时期的应力方向可以是各不相同的,同一地区在不同地质时期内的构造应力方向也是截然不同的,并且应力方向的转变周期也不相等。在概述了应力大小的研究方法之后,作者介绍了构造应力大小研究中的两个新成果:(1)构造应力主要集中在岩石圈内,(2)构造应力从板块边缘向内部具有明显的衰减趋势。至于构造应力积累时间,一般认为是n×10 ̄7年的缓慢过程,而应力释放时间则为n×10 ̄6年的过程,是一种灾变性、较快的流变过程。构造应力场数学模拟方法已经比较成熟,构造应力的起源问题则为当今构造地质学的前沿性课题之一,对此本文较客观地进行了探讨。  相似文献   

17.
在传统的库伦土压力理论中,刚性挡墙后无粘性填土中的破裂面被假定为平面。然而,一些室内试验和现场测试结果均已证明了实际破裂面是曲面。以刚性挡墙后无粘性填土中的破裂面为研究对象,以竖向微分单元法为基础,利用变分原理推导了主、被动状态下关于破裂面曲线的微分方程,并对该方程进行了求解。研究结果表明,当墙背光滑或墙背与土体的摩擦系数为定值时,填土中的破裂面和破裂角均与库伦土压力理论相同;当墙背与填土的摩擦系数呈线性规律变化时,对应的破裂面为曲面。最后,讨论了墙背摩擦角和填土内摩擦角对破裂角的影响。  相似文献   

18.
A detailed examination of the frequency content of ground vibration is presented in terms of the so-called instantaneous frequency and time-frequency analysis. These techniques, and others, are applied to the surface vibration from a mass blast that triggered a large seismic event and to an earthquake vibration measured in the walls of a massive dam. As an associated issue it is shown that the relationship between peak levels of acceleration and velocity also reveals information on the frequency content of ground vibration. It is demonstrated quite clearly that the popular zero-crossing method cannot be used to obtain the frequency associated with the peak vibration level. In fact it is a false notion that one particular frequency can be associated with the peak level except for the ideal (and impractical) case of a single sinusoid. Realistically, there is a distribution of frequencies associated with the peak level, and a technique of sliding filters is suggested in order to examine the dependence of the peak level upon this frequency content. In light of the sliding filter approach, a new frequency dependent criterion for allowable levels of vibration is presented. This criterion is a completely continuous and well-defined function of frequency and so is more realistic than the current criteria which are only piecewise continuous and based upon an ill-defined frequency. The new criterion is applied to vibration data obtained from quarries and underground operations and is also applied to a model of resonant vibrations in urban dwellings.  相似文献   

19.
实散组合桩承载原理及应用   总被引:4,自引:1,他引:3  
本文提出了实散组合桩概念,即一根桩由上下两段组成,上段是实体桩,下段是散体桩。这样就克服了散体桩通常桩头承载能力低的缺陷。本文对实散组合桩的受力概念进行了分析研究,给出了其承载力、沉降、临界桩长等计算方法和公式。最后介绍了首次工程实例。  相似文献   

20.
The mechanism underlying rain-induced shallow landslides of non-welded ignimbrite is found to be a special type of weathering profile and the behavior of water infiltrating through that profile, according to our study of Ito ignimbrite in southern Kyushu, Japan. Rhyolitic volcanic glass, the primary component of ignimbrite, is first hydrated and dissolved, forming halloysite. Halloysite near ground surface is then transported through the ignimbrite by infiltrating water and becomes clogged in interstices to form clay bands. Suction monitoring across a weathering profile indicated that downward infiltration of water is disrupted once by a zone of less-permeable clay bands and again at the weathering front. This disruption at the front is caused by a capillary barrier effect caused by the structure where finer, weathered material overlies coarser, fresh material. This results in a well-defined weathering front, particularly beneath a slope where water flux is parallel to the front, whereas the front is transitional beneath a ridge top where the front is nearly horizontal and the water flux is normal to the front. Infiltrating water from rain increases the weight of weathered material and decreases the suction within the material, which is the final trigger of a shallow landslide of non-welded ignimbrite; long-term weathering, which proceeds on the order of years, provides slide material.  相似文献   

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