Yangshan Gold Deposit:The Largest Carlin and Carlin-like Type Gold Deposit in China   总被引：5，自引：0，他引：5  

YAN Fengzeng  LI Qiangzhi 《《地质学报》英文版》2008,82(4):804-810

Gold Headquarter of the CAPF has discovered the Yangshan super large-scale gold deposit in Gansu Province, which is a great breakthrough of gold exploration and prospecting in Western Qinling Mountains of China. The gold resources of this deposit achieved 308 tons with increasing potentials. Preliminary geological investigations indicate that the Yangshan gold deposit is located in the intra-continental collision orogenic belt; and the deposit was formed during the continent-continent collision orogenic processes. The geological characteristics of the deposit are similar to that of the typical Carlin-type gold deposits, while differences still exist. The ore-forming background is notably different from the Carlin gold deposit province in the United States; and the ore-forming fluids are similar with that of the orogenic-type gold deposit. Accordingly, the Yangshan gold deposit is a transitional type between the Carlin-type and the orogenic type gold deposits. At present, the Yangshan gold deposit is the largest Carlin and Carlin-like type gold deposit that is ever discovered in China. Researches on metallogeny, metallogenic model and ore-enrichment regularities of the Yangshan gold deposit are crucial to meet the pressing needs of the current geological investigation and ore exploration of the deposit.  相似文献   

透视圆锥投影的研究     

刘宏林  吕晓华  安敏 《测绘科学技术学报》2001,18(4):300-302,306

分析了获取透视圆锥投影的原理和方法,推导出了透视切、割圆锥投影的一般公式,给出了透视切、割圆锥投影的几个特例,并对各种圆锥投影的变形进行了比较分析.结果表明,透视圆锥投影用于小比例尺地图的制作是可行的.  相似文献   

利用坐标反复算直线坐标方位角的最佳数学模型     

谭家兵  刘星 《江苏测绘》2001,24(3):24-25,27

本文通过对反算坐标方位角的数学模型进行分析，得出反正切函数是最佳反算直线坐标方位角数学模型的结论。  相似文献   

图像重建的射线交切反投影法   总被引：1，自引：0，他引：1  

周海南 《CT理论与应用研究》1992,(3)

本文详述了一种快速图像重建方法——射线交切反投影法。它吸取了代数重建算法的某些长处,但无迭代计算,简单实用,对于野外作业使用更显得方便,利用此方法,重建了实测的电磁波吸收系数图像,它比传统的阴影交汇法有更好的分辨率。  相似文献   

岩石断面的分形测量及其分维的计算   总被引：7，自引：0，他引：7       下载免费PDF全文

施行觉  牛志仁 《地球物理学报》1992,35(2):154-159

在实验室内使岩石单轴压缩直至破裂,用位移传感器测量其断面高度,用显微镜观测断面切片的剖线,所得数据用尺度法计算其分维,各种岩石的不同曲线的分维在1.002-1.028之间,与野外断层主迹线分维值相同.用切岛法计算整个断面的分维约为2.05左右.有关分析和计算认为,分维的大小与岩石破裂时所受力的方向有关,与采样步长有关,而与岩石样品的大小无关.  相似文献   

黄土区切沟对不同植被下土壤水分时空变异的影响   总被引：2，自引：0，他引：2       下载免费PDF全文

张晨成  邵明安  王云强  贾小旭 《水科学进展》2016,27(5):679-686

为掌握切沟对土壤水分时空变异的影响,选取水蚀风蚀交错区两个典型切沟样点为研究对象。采用时间序列分析和经典统计学方法,从土壤水分时间变化特征和空间分布格局两方面探讨。结果表明:距沟道不同距离下土壤储水量差异明显。300 cm处样点可作为测定尺度下土壤储水量平均值。土壤水分在垂直方向上的变异受植被特征影响,沟道影响较小。坡面土壤储水量的空间分布呈现不同的分布格局。坡顶风速大,土壤水分蒸发快,坡中处土壤储水量最高,为949.9 mm,距切沟越近土壤水分快速散失,坡下土壤水分接近4%,亏缺严重。杏树地土壤储水量远高于柠条地,柠条地土壤储水量分布较为单一。土壤蒸发、植被、沟道等因素使得坡面土壤水分分布更加复杂。  相似文献   

蚁群算法在 InSAR 相位解缠中的应用     

石超  田林亚  熊欢欢  祖滢 《测绘工程》2016,25(12)

相位解缠是InSAR信号处理的关键过程,针对传统的枝切法存在枝切线整体长度过长和容易产生解缠"孤岛"现象等问题,基于蚁群算法提出一种改进的枝切法,通过对传统的枝切线进行优化,有效地减少枝切线长度。采用伊朗Bam地区的InSAR图像数据对算法进行实验计算与分析,表明本文算法所需设置的枝切线整体长度较短,能获得更好的相位解缠效果。  相似文献   

SUBDIVISIONS OF THE JURASSIC, CRETACEOUS AND TERTIARY COAL-BEARING STRATA OF RUSSIAN MARITIME AND AMUR PROVINCES, AND OF SAKHALIN ISLAND     

E.E.AHNERT  A.I.LAUROUSHIN 《地质学报》1924,(Z1)

As is well known, the first information on the coal-bearing strata of the Russian Far East and their characteristic fossil flora was given by the acadeinician Prof. Schmidt (2), and his fellow-traveller Glehn (13), to Lopatin, Bogoluibsky (9), A. Koeppen (26) and others. However the  相似文献   

MIGRATION OF GEOSYNCLINES   总被引：3，自引：0，他引：3  

A.W.GRABAU 《地质学报》1924,3(3):207-318

The term geosyncline was applied by J. D. Dana in 1873 to the long earth trough in which he conceived that the strata now involved in the folds of the Appalachian Mountains of eastern North America were deposited. He extended this term to include all similar earth troughs, whether simple or complex, which are iormed in regions of excessive deposition. Such earth  相似文献   

THE UPPER CARBONIFEROUS OF FERGANA AND THE QUESTION OF THE BOUNDARY BETWEEN THE CARBONIFEROUS AND THE PERMIAN     

BORIS LICHAREW  LENINGRAD USSR 《地质学报》1934,(0)

The study of the Upper Carboniferous has been attracting much attention recently and the question as to its extent and stratigraphy has been the object of very serious discussion, but so far without any positive results. The large territory of the Soviet Union affords no doubt great possibilities for the  相似文献