Deep-seated structure and gold content of Russia and China contiguous territories

来源 :世界地质(英文版) | 被引量 : 0次 | 上传用户:asdfghjkh
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
On the contiguous territories of southeastern Russia and northeastern China, many gold-bearing areas are conjugate in space with the gradient zones of the gravity field. Large gold-ore districts, defining in many respects the metallogenic signature of the region, are located on the joints of differently oriented gradient zones. In the best-studied districts, the Precambrian protrusions, staged distribution of magmatic chambers (by vertical) above the Mohorovicic discontinuity and restriction to the peripheral parts of intrusive massifs have been recognized. Different-type gold deposits in the studied ore-placer districts and nodes are often located on the areas of joint of the granitoid massifs and subvolcanic bodies with depressions. Availability of areals of metasomatic alterations of rocks, placers, and ore occurrences of precious metals on such but poorly studied areas can serve as the basis for the revision and detailed forecasting-prospecting works to develop the mineral-raw material base of the region for precious metals.
其他文献
随着现代化农业种植方式,小麦粉的产品质量有了很大的提高.但是我普通小麦粉产品标(GB1355-1986)却一直没有改变.本文就小麦粉的标准问题做了探讨.
施工图预算在建设程序中对造价控制意义很大,本文主要讲述其两种编制方法、审核及一些注意事项。 The construction drawing budget has a great deal of significance in c
据统计调查,从公元前26年至今的2千余年里,四川省至少有9次地震事件形成过堰塞湖。本文简述了这9次地震堰塞湖及其灾害情况,并在此基础上分析总结出地震堰塞湖形成的充分条件为:所在地区地震烈度大于等于Ⅷ度,且堰塞湖的数量和规模与烈度值呈正相关关系;地形为高山峡谷江(河)段,两岸或一侧为高陡的岩壁或台地前缘;岩性条件为江(河)两岸或一侧存在较破碎的基岩或巨厚的松散堆积体。在满足上述充分条件下,若恰遇雨季
不同角的投影方法,其相关投影以及获得的工程图形是截然不同的,它将对识绘图形产生重大的影响,要想把握和运用不同的投影方法来表达机件,就必须探讨不同角的投影关系和其比较
1500×600-635轮胎是调压型越野轮胎,其断面高宽比较小,要求具有较高的通过性能,因此在结构设计方面有其自身的特点.介绍了该轮胎技术设计和施工设计的特点,轮胎外直径、断面
An approach based an multi-scale chirplet sparse signal de-composition is proposed to separate the multi-component polynomial phase signals, and estimate their
为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7
分析了鲁台子站地表径流逐年下降的趋势。将1980年迄今的资料近似作为一致性系列,进行频率计算,发现实测和还原系列几乎是同频率相应的,结果表明,在小水年份,径流减少较多,为
Latest advances in network sensor technology and state of the art of mobile robotics and artificial intelligence research can be applied to develop autonomous a
研究目的:研究中国耕地保护的现状,构建数量质量并重的耕地保护体系.研究方法:文献资料法和因果分析法.研究结果:(1)中国耕地保护的现状是耕地面积逐年减少、等级不高、分布