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1.
2007年8月31日,国家重点工程温一福铁路(福建段)再传捷报。亚洲最大的铁路疏解隧道群——温-福铁路鼓山隧道群、全线控制性重点工程八仙仑隧道提前2个月顺利贯通。为温-福铁路按期铺轨奠定了坚实的基础。温-福、福-厦、温-厦三条铁路都要从这里经过。6座隧道3座桥梁立体交叉,形成亚洲最大的铁路疏解隧道群。保证温福铁路2009年6月底建成通车。鼓山隧道群位于鼓山风景区4是由6座隧道(燕前一、二、三号,鼓山一、二、三号)和3座桥梁组成的上下交错、两两互通的立体交叉系统。也是亚洲首条洞内双开岔铁路隧道群。它将温-福、福-厦、温-厦三条铁路在山体内实现了疏解。鼓山隧道群中,燕前二号隧道为沿海通道主干线,有两处燕尾加宽段共计13个变化断面。第一处燕尾段向右分岔形成燕前三号隧道即温-福上行联络线。后并人鼓山一号隧道跨104国道特大桥驶入福州;第二处燕尾段向左分岔形成燕前一号隧道即温福下行联络线。使得燕前二号阻道成为亚洲最大的“一洞变三洞的”双分岔式隧道。鼓山三号隧道与鼓山一号隧道为单分岔隧道。  相似文献   

2.
Many important metal resources, such as Ni (Cu, Co), PGE, exist in magmatic sulfide deposits, are a hot spot in geological research. We divide the magmatic sulphide deposits in China into four types according to their tectonic setting, intruding mode, ore deposit mode, main metallogenic elements. The four types are as follows: (1) Small-intrusion deposits in paleo-continent; (2) Smallintrusion deposits in continental flood basalt; (3) Small-intrusion deposits in orogenic belt; and (4) The deposits associated with ophiolites. On the basis of the classification, we put forward that the main magmatic metallogenic type in China is small-intrusion metallogeny, and describe its characteristics from small intrusions related concept, three geologic settings, three volcanic-intrusive assemblages and metallogenic key factors. According to the experiences of prospecting at home and abroad, we point out that there is big potential in prospecting small-intrusion deposits, which need further study. At last, we indicate that small-intrusion metallogeny not only widely distributes in mafic-ultramafic intrusions, but also has an important economic value and scientific significance in intermediate-acid intrusions.  相似文献   

3.
用齐波分布律和阻尼曲线现象进行矿产资源预测,具有采用数据少,计算方法简单的特点,与元素丰度模型法,黎彤法等方法预测的结果基本相当,夹皮沟金矿田是一研究程度与开采程度都很高的地区,运用齐波夫分布律和阻尼曲线现象对其进行预测,夹皮沟金矿田仍有500t左右的潜在资源量,找矿潜力达74%,尤其是沿主剪切带附近,仍有大型,超大型矿床隐伏,只是勘探深度要大大增加。  相似文献   

4.
甘肃永靖盐锅峡早白垩世翼龙足迹的发现及意义   总被引:3,自引:0,他引:3  
甘肃永靖盐锅峡恐龙足迹1号化石点中保存有翼龙足迹, 该足迹是我国翼龙足迹的首次发现.翼龙足迹为四足行走, 行迹宽.前脚为不对称三趾型, 趾行式, 其中Ⅱ趾最短, Ⅳ趾最长, 足迹外偏, 偏角大, Ⅳ趾与行迹交角为160°~ 180°.后脚外形为近长方形, 四趾型, Ⅱ、Ⅲ趾较Ⅰ、Ⅳ趾长, 行式, 脚长为宽的3倍, 足迹外偏, 偏角30°.足迹特征表明该翼龙足迹属于一新种.沉积特征表明翼龙足迹产于湖岸环境.   相似文献   

5.
Leaching Behavior of Fly Ashes from Power Plants   总被引:1,自引:0,他引:1  
The Yanzhou mine district, located in southwestern Shandong Province, is about 1300 km2 with more than 8×109tons of proved coal reserves and there are 10 big power plants in this area. A large amount of coal ashes, which are regarded as waste materials, have been stockpiled in the area and have influenced the environment of the mine district. In this paper, analysis of fly ash samples from three power plants is carried out, the enrichment and concentration of trace elements, Pb, Zn, Cu and As, in coal ashes are analyzed, and petrological and mineralogical characteristics and chemical compositions of coal ashes are studied. The aim of this work is to provide basic scientific data for utilization of ashes and reduction of environmental pollutions.  相似文献   

6.
Muller高原位于巴布亚新几内亚南部高地,以发育大漏斗(giant doline)群而闻名.这些漏斗中许多具有可与新不列巅岛Nakanai山地的超级漏斗(megadoline)和中国南方喀斯特天坑相媲美的特大规模和形态,都属"岩盖(caprock)"型漏斗.Muller高原的地质、自然地理和水文环境可与Nakanai山地环境和中国南方喀斯特区环境相对比.本文讨论了Muller高原上三个大漏斗群(Rogorepo,Mamo和Atea)的形成机制.Muller高原的大漏斗,像Nakanai的超级漏斗和中国天坑一样,形成于更新世.Muller高原漏斗的形成环境与其它大漏斗有许多相似性.然而,它却不可能演化成像Nakanai超级漏斗一样壮丽,像中国天坑那样具有极高美学价值,其原因在于石灰岩地层中有不纯非石灰岩夹层.  相似文献   

7.
Silver occurs in South China wolframited-quartz veins in three forms:(1)as micro inclusions of Ag2S and AgBiS2,(2) as argentite and matildite as a result of exsolution and(3)as Ag-bearing sulfosalts and independent silver minerals.According to mineral assemblaged the Ag-bearing tungsten deposits are classified as two types:(1)Ag-bearing W-Bi deposits in eastern Nanling,where gustavite has been found and(2)Ag-bearing W-Sn(Sb)deposits which are mainly distributed in western Nanling.The authors consider that the enrichment of silver and sulfosalt minerals in the lower parts of pneumato-hypothermal tungsten deposits is the result of reversed vertical zoning caused by high concentrations of F and S in the ore-forming fluids.  相似文献   

8.
大气中除了二氧化碳以外,更有痕量气体在增加。它们象二氧化碳一样对全球气候起着明显的影响。这个看法是四位科学家在即将问世的一篇论文中提出来的。他们还说,比较重要的一点在于这些痕量气体能长此以往地继续起着“暖房”作用,比二氧化碳有过之而无不及。该文将发表在今年六月号的《地球物理研究》杂志上。 “这些痕量气体在今后40到50年里对气候变暖的影响要超过二氧化碳的两倍或三倍。”其中一位作者R.J.西塞尔朗这样说的。他目前是美国国家大气研究中心(NCAR)大气化学研究室主任。这个结论是他的研究组对近40种痕量气体中某些气体的附加影响的研究中得出的。另一位作者,国家大气研究中心气候模型制作人V.拉曼纳沙  相似文献   

9.
Widespread in more than ten provinces of southern China are the Lower Cambrian black argillaceous-arenaceous rock series consisting of black carbonaceous shales,black carbonaceousargillo-siliceous rocks,black carbonaceous silicolite and black silicolite and black carbonaceous argillaceous siltstone.The Ni,Mo,V,Cu,U,Ba,Ag,P contents of these series are usually several to tens of times higher than their average values in shales.As viewed from lithological sequence,element association and evolution,these black series can be diveided into two types.There occur a variety of deposits in the black rock series,such as phosphorite deposits,Ni-Mo-V polymetal deposits and “Stone coal“ seams.According to ore composition,texture and structure,the phosphorite deposits fall into three types,i.e.,thick-bedded,lenticular and nodular,The Ni-Mo-V polymetal deposits,V deposits and reworked sedimentary CU-U-Cd polymetal deposits in terms of their element assiciation and ore genesis.As for the stratiform deposits in the black rock series,three mineralization stages have been recognized,i.e.,the formation of phosphorite deposits,of Ni-Mo polymetal deposits and of V-Cu-U-Cd polymetal deposits as well as of “:stone coal“ seams.Evidence strongly suggests that lower organisms have played an important role in mineralization. Our studies indicate that the Lower Cambrian black argillaceous-arenaceous rock series in southern China and their associated stratiform deposits occur generally in the basal parts of a big sedimentary cycle,i.e.,the initial period of a transgression,or in the fine detrital-siliceous formation between two carbonate formatons,formed in a humid climatic zone between two arid ones.As for the environment of deposition,it is suggested that the Lower Cambrian black argillaceous-arenaceous rock series and associated stratiform deposits(excluding thick-bedded phosphorite deposits)were formed mainly in a restricted and poorly-fed sea basin of stagnant shallow water containing abundant lower or ganisms and organic matter under statically hydrodynamic conditions.  相似文献   

10.
In the Phanerozoic, there are three major geological boundaries: Precambrian/Cambrian.Permian/Triassic and Cretaceous/Tertiary. Studies of these boundaries in China and over the world stronglysuggest that they have the following similar features: mass extinctions of many taxa, positive anomalies ofplatinum-group metals, and abrupt changes of stable isotopes (δ~(13)C). It is quite probable that these were theconsequences of some rare catastrophic events of extraterrestrial origin. Hence, the three above-mentionedmass extinction events may be regarded as key indicators for the division of the geological history of thePhanerozoic.  相似文献   

11.
滑坡与泥石流是不同的地质现象(作用),但又彼此相关.往往是滑坡导致泥石流,或者泥石流促使滑坡发生.它们常伴随出现.滑坡泥石流的分布与危害,世界许多地区都存在.与地震灾害一样,它们可以中断交通、堵塞河道、摧毁厂矿、掩埋城镇、破坏生态平衡.按照城镇遭受滑坡泥石流危害的主要原因,大致划分为三种类型。一、工程地质环境不良型(简称环境不良型)  相似文献   

12.
叶大年教授的专著《结构光性矿物学》是他二三十年来孜孜不倦地研究矿物晶体结构与光学性质关系方面一系列重要成果的全面总结.作者的研究不仅将拉尔森等人开创的光性矿物学推进到了光性与晶体结构、原子结构的新阶段,而且提供了许多精确定量的定律、原理和方法.无论从实验数据积累及理论意义这两方面来看,本书在光性矿物学研究历史上的影响是不可低估的.本书共七章,其中第一章为基本知识简介.二、三、四章讨论了折射率与矿物成分、密度、原子结构及晶体结构的关系,这三章的内容是全书的重点章节,也是作者二十多年来研究成果最多的领域,作者全面地介绍了折射度的概念、格拉斯顿一代尔定律、洛仑茨一洛仑兹定律及阿仑折射度定律.运用上述定律,在已知成分和密度的情况下,一般可以计算矿物  相似文献   

13.
下庄矿田湖子地区铀矿找矿方向探讨   总被引:2,自引:0,他引:2       下载免费PDF全文
湖子地区位于NNE向诸广-新兴铀成矿带与近EW向大东山-漳州大断裂复合部位,是华南早、晚两期铀成矿热液活动叠加区、放射性高场区,既有"硅化带大脉"型铀矿产出,又有"交点"型铀矿存在,找矿前景良好.文章在论述下庄矿田铀成矿地质环境、铀成矿特征及铀矿定位条件基础上,分析了湖子地区铀成矿条件与找矿前景,指出该区今后铀矿找矿方向是:① 6009号硅化断裂带,在其北段找硅化带大脉型铀矿,在其南段找"交点"型铀矿;②新桥-下庄硅化断裂带和6009号带之间成矿部位,寻找硅化带型和"交点"型铀矿;③NW向、近EW向辉绿岩脉与NNE向、NE向构造交汇部位(交点),寻找"交点"型铀矿.  相似文献   

14.
The Longbohe Cu deposit, which is located in the southern part of the Honghe ore-forming zone, Yunnan Province, China, belongs to a typical ore field where volcanic rocks are of wide distribution and are associated with Cu mineralization in time and space. The volcanic rocks in the ore field, which have experienced varying degree of alteration or regional metamorphism, can be divided into three types, i.e., meta-andesite, meta-subvolcanic rock and meta-basic volcanic rock in accordance with their mineral assemblages. These three types of volcanic rocks in the ore field are relatively rich in Na and the main samples plot in the area of alkali basalts in the geochemical classification diagram. With the exception of very few elements, these three types of volcanic rocks are similar in the content of trace elements. In comparison to the basalts of different tectonic settings, the meta-volcanic rocks in the ore field are rich in high field strength elements (HFSE) such as Th, Nb, etc. and depleted in large ion lithophile elements (LILE) such as Sr, Ba, etc. and their primary mantle-normalized trace element patterns show remarkable negative Th and Nb anomalies and negative Sr and Ba anomalies. These three types of volcanic rocks are similar in REE content range and chondrite-normalized REE patterns with the exception of Eu anomaly. Various lines of evidence show that these three types of volcanic rocks in the ore field have the same source but are the products of different stages of magmatic evolution, their original magma is a product of partial melting of the metasomatically enriched mantle in the tensional tectonic setting within the continent plate, and the crystallization differentiation plays an important role in the process of magmatic evolution.  相似文献   

15.
广西合浦、南宁、宁明等第三系盆地的主要烃源岩层与百色盆地一样,均是中始新统深湖-半深湖相暗色泥质岩层,特点是分布面积广,厚度大,有机质丰度高.有机碳含量多数大于2.0%,达到"好"到"最好"的评价标准.有机质成熟度多数处于低熟阶段,部分在成熟阶段.干酪根类型主要为Ⅱ1型.综合分析认为:合浦、南宁、宁明三个盆地都具有优质...  相似文献   

16.
辛莉莉 《岩矿测试》1983,(2):142-143
本文在资料邻苯三酚红(十六烷基三甲基氯化铵)三元络合物在硝酸介质中测定钨的基础上,研究了钨与溴邻苯三酚红(溴代十六烷基三甲基胺)三元络合物的测定条件,提出在硫酸介质中,用溴邻苯三酚红(溴代十六烷基三甲基胺)三元络合物不经分离测定含铬高的矿石中的钨。在盐酸羟胺、EDTA存在下,二十余种阴、阳离子不干扰测定,特别是铬(Ⅵ)的允许量可达30倍以上。方法简便快速,其克分子消光系数为4.8×10~4。0—200微克WO_2/50毫升符合比尔定律。所测络合物组成为:  相似文献   

17.
在0.05—1.28N的硝酸介质中钍同偶氮溴膦-mK反应,形成蓝紫色络合物。络合物稳定48小时,λ_(max)=680nm,△λ=130nm,ε=8.55×10~4,钍在0—30μg/25ml范围符合比尔定律。当体系中加入阳离子表面活性剂TPB后灵敏度至少提高三倍,钍在0—5μg/25ml范围内符合比尔定律,可用于微量钍的测定。  相似文献   

18.
郎殿有 《地质与资源》1997,6(3):193-198
乌拉山金矿带金矿化分为石英脉型(Ⅰ),石英脉-蚀变岩型(Ⅱ),蚀变岩型(Ⅲ)三大类型,其分带性与大桦背花岗岩具有密切空间关系.  相似文献   

19.
Based on the Rb-Sr isotopic study of the granitoids in the Hengduan Mountains, the classification andgeologic significance of whole-rock Rb-Sr isochrons as well as the factors influencing homogenization of theisotopic systems are discussed. Usually. there is no good linear correlation of isochrons for diorites andalkali-rich intrusive rocks (including alkaline rock and alkalic granite). But by means of the external isochron ofmonominerals from the rocks. isochrons with good linear correlation as well as ages and Sr initial ratios with ahigh confidence can be obtained. In order to obtain a satisfactory isochron, the discriminant parameters shouldbe calculated from the Rb/Sr ratios and estimated ages of samples. Only those that meet the requirements canbe used as the Rb-Sr isochrons. The quality of an isochron should be judged from three factors, i.e. correlationcoefficient. MSWD and homogenization degree.  相似文献   

20.
Some conodonts described by Tea Kolar-Jurkovsek and Bogdan Jurkovsek (2007) from the Permian-Triassic boundary section in the ?iri area of western Slovenia are revised in this paper. One specimen that they assigned to Hindeodus parvus is tentatively regarded as Hindeodus cf. scalaris Wu 2005. Two specimens that they assigned to Isarcicella sp. A is changed to Hindeodus parvus. One specimen that they described as Isarcicella lobata Perri and Farabegoli is changed to Hindeodus crenatus Wu (2006). One specimen that they assigned to Isarcicella turgida (Kozur, Mostler and Rahimi-Yazd) is changed to Hindeodus cf. parvus. Since these revisions, the three conodont zones that they defined have been correspondingly revised. Their first zone may belong to Hindeodus parvus zone, but it is not certain. Their second zone is changed to the Hindeodus parvus zone, and their third one remains as is.  相似文献   

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