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乌拉尔这个名字,对于我们來說并不十分陌生。地理上歷來就把这个2000多公里長的烏拉尔山脉,作为亞洲和欧洲的分界碑。翻开苏联地圖,可以很清楚地把苏联的地面分为兩大部分:从叶尼塞河往东,大部分是高地和山脉;从叶尼塞河往西,除極南部分以外,大部分是平原。乌拉尔山脉就將此比较平坦的西部又分隔为兩个平原,烏拉尔以西叫东欧平原(又称俄罗斯平原),烏 相似文献
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河北省徠源縣,是我國久已著称的石棉礦区之一。在涞源境內,計有好几处石棉產地,其中最重要的一个則属烟煤洞(图1)。其他地点多未進行开 相似文献
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为研究乌伦古湖矿化度和氟化物浓度与各水量因子间的定量关系,本研究以水量平衡和物质平衡为基础,把影响湖水水质的原因分为降雨、蒸发、河流补给、地下水补给以及地下水流出5个水量因子,定量分析湖水矿化度和氟化物浓度与各水量因子之间的关系,并且预测了湖水矿化度和氟化物浓度的动态变化.结果表明,地下水输出流量决定了湖水中矿化度和氟化物浓度,地下水输出流量越大,湖水中的矿化度和氟化物浓度越小.2010年至今乌伦古湖水位的升高导致了地下水输出流量增大,乌伦古湖内的矿化度和氟化物浓度均呈缓慢下降趋势,模型预测新的稳态下湖水中矿化度为1.68 g/L,氟化物浓度为1.70 mg/L,在地下水输出流量不变的情况下达到新的稳态所需时间大约为50 a. 相似文献
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Two types of gold ores,siliceous mylonite and quartz vein,formed at the first and second stages of mineralization respectively, can be clearly recognized in the shear zone-hosted gold deposit at Jinshan, Jiangxi.Similarity in REE and trace elements between the siliceous mylonite and the country rocks indicates that the ore metals were supplied by the surrounding strata during the first stage of mineralization.On the other hand, as indicated by fluid inclusion data,the ore-forming fluid at the second stage was of meteoric origin and the precipitation of gold was caused by phase separation. 相似文献
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Geochemical Studies on Au Distribution and Mineralization in the Northwest Jiangxi Terrain 总被引:1,自引:0,他引:1
The Middle Proterozoic Jiuling Group,one of the most important geologic unit in the Northwest Jiangxi Terrain,is a kind of Au-bearing formation with a Au-Ag-As association,and its geotectonic setting belongs to the ACM area.Granitification can supply Au with favorable complexing agents.Later granitification os of much more significance in mineralization.Regional Aumineralization includes two types;metamorphic hydrothermal solo-Au mineralization in the northern part and magma gydrothermal superimposed polymetallic mineralization with Au,Ag,etc,being dominant in the southern part.Regional exploration should center aroud the Jiujing Group,small granite bodies of later periods and fault structures,while paying attention to the anomalies of trace elements such as Au,Ag,As,Pb,Zn,etc. 相似文献