中国金矿床工业类型     

李景春  庞庆邦  李文亢  邵军  李舒 《地质与资源》1998,7(2):114-120

作为勘查和开发直接对象的含金地质体是金矿床工业价值的决定性要素,是金矿床地质特征的本质规定,也是人们最易识别和掌握的直观标志,以此作为金矿床工业类型的分类基础,划分出10类金矿床:（1）石英脉型;（2）糜棱岩型;（3）蚀变碎裂岩型;（4）冰长石-绢云母石英脉型;（5）角砾岩型;（6）矽卡岩型;（7）微细浸染型;（8）红土型;（9）铁帽型;（10）砂砾层型  相似文献   

两种形态ENSO对南半球热带外气候变化特征的影响          下载免费PDF全文

万伟杰张召儒  刘海龙周朦 钟贻森 《极地研究》2018,30(4):376-390

本研究利用1979—2012年欧洲中期天气预报中心(ECMWF)的ORAP5(Ocean Reanalysis Pilot 5)海洋/海冰再分析资料和ERA-Interim气象再分析资料,采用回归分析方法,分1979—1998年和1999—2012年两个时间段探讨了南半球热带外地区气候变化对两种不同形态ENSO的响应特征。结果表明,南半球热带外区域气候在1999年前后两个时段对ENSO的响应表现出了较大的年代际变化特征。1979—1998年南半球热带外气候变量对Nio3指数在时间上的相关性和空间上的响应强度都普遍大于Nio4指数,说明这一时段东部型ENSO对南半球热带外区域气候变化的影响要更强一些。在1999—2012年,不同形态ENSO与气候变量的相关性大小并无明显的规律,而且空间响应场的差异性并不大。海平面气压、风场和气温对ENSO变化的响应在南半球冬季表现最为强烈,在夏季最弱。三者在1999—2012年秋季对Nio3指数和Nio4指数的响应场中出现了纬向三波数结构。1999—2012年冬季,有异于海平面气压和风场,在罗斯海和阿蒙森海海域海表气温对Nio4变化的正响应明显强于对Nio3的响应,该特征在混合层温度中也有体现,表明海表气温随ENSO的变化受海洋特征变化影响较大。混合层深度和混合层温度的响应场之间存在很大的相关性,混合层温度响应在秋季表现最强,春季最弱,混合层深度响应与之相反。在1979—1998年,海冰密集度对不同Nio指数变化的响应差异主要出现在海冰结冰季节,而海冰厚度对不同Nio指数变化的响应差异在夏季表现较强。海冰密集度和厚度对Nio3变化响应的年代际差异在秋冬季节更加明显,对Nio4变化响应的年代际差异在秋、冬、春季都较明显。  相似文献   

Time‐series photometric spot modelling – VI. A new computer code and its application to 23 years of photometry of the active giant IM Pegasi     

G. Ribrik  K. Olh  K.G. Strassmeier 《Astronomische Nachrichten》2003,324(3):202-214

We present and apply a new computer program named SpotModeL to analyze single and multiple bandpass photometric data of spotted stars. It is based on the standard analytical formulae from Budding and Dorren. The program determines the position, size, and temperature of up to three spots by minimizing the fit residuals with the help of the Marquardt‐Levenberg non‐linear least‐squares algorithm. We also expand this procedure to full time‐series analysis of differential data, just as real observations would deliver. If multi‐bandpass data are available, all bandpasses can be treated simultaneously and thus the spot temperature is solved for implicitly. The program may be downloaded and used by anyone. In this paper, we apply our code to an ≈23 year long photometric dataset of the spotted RS CVn giant IM Peg. We extracted and modelled 33 individual light curves, additionally, we fitted the entire V dataset in one run. The resulting spot parameters reflect the long term light variability and reveal two active longitudes on the substellar point and on the antipode. The radius and longitude of the dominant spot show variations with 29.8 and 10.4 years period, respectively. Our multicolour data suggests that the spot temperature is increasing with the brightening of the star. The average spot temperature from V, I_C is 3550 ± 150 K or approximately 900 K below the effective temperature of the star.  相似文献   

The total‐to‐selective extinction ratio determined from near IR photometry of OB stars     

W. Wegner 《Astronomische Nachrichten》2003,324(3):219-237

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Flare stars in the TW Hydrae association: the HIP 57269 system     

B. Knig  R. Neuhuser  E. W. Guenther  V. Hambaryan 《Astronomische Nachrichten》2003,324(6):516-522

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Types and genesis of manganese oxide ores in Guangxi, Southwest China     

刘腾飞 《中国地球化学学报》1999,18(1):87-96

Systematic studies are diven to the genesis and spatial distribution of manganese oxide deposits in Guangxi,Southwest China.The deposits are classified as 3 types and 7 subtypes among which the karst depression type is regionally characteristic an of reat potential.A genetic model is presented for the mineralization on the basis of proto-rock,tectonic background,topographic features and climatic and hydrogeological conditions.  相似文献   

Massive Sulphide Deposits Related to the Volcano-Passive Continental Margin in the Altay Region   总被引：3，自引：0，他引：3  

WANG Jingbin  DENG Jiniu  ZHANG Jinhong  QIN KezhangBeijing Institute of Geology for Mineral Resources  State Bureauof Nonferrous Metal Industry  Andingmenwai  Beijing Zhu Xiling 《《地质学报》英文版》1999,73(3):253-263

The Devonian volcano-passive continental margin in southern Altay is a significant volcanogenic massive sulphide metallogenic belt. Acidic volcanism has been dominant on the inner side of the volcano-passive continental margin, i.e., near the old land, resulting in a Pb-Zn metallogenic sub-belt, in which the ore deposits are hosted by sedimentary rocks in volcanic series, as represented by the large Koktal Pb-Zn deposits. In the central part of the margin far away from the old land, bimodal volcanic formations are well developed, forming volcanics-hosted Cu-Zn metallogenic sub-belts, e.g., the large-scale Ashele Cu-Zn deposit. The Qiaoxiahala sub-belt on the outer side of the margin near the ocean ridge is located at the spreading central trough, where ophiolite suites are developed. This type of deposits is rich in gold and copper, similar to the Cyprus-type Fe-Cu-Au metallogenic sub-belt in metallogenic environment (represented by the Qiaoxiahala medium-scale Fe-Cu-Au deposit). From the old land to th  相似文献   

豫陕晋金三角金矿成矿探讨   总被引：2，自引：0，他引：2       下载免费PDF全文

彭大明 《地质找矿论丛》1999,14(4):40-48

豫陕晋金三角是我国重要的黄金生产基地。该金三角的成矿条件极为优越,处于多构造体系复龠 我间,地层出露齐全、岩浆活动强烈、控金断裂系统网络交织、金源层（体）广布,所以金的成矿类型繁多,金矿床星罗棋布,文章对该区金矿成矿作专题探讨。  相似文献   

地洼盆地砂岩铜矿床的构造-流体-成矿体系及演化   总被引：2，自引：0，他引：2  

谭凯旋  龚文君  李小明  龚革联 《大地构造与成矿学》1999,23(1):35-41

我国南方地洼盆地构造演化、流体演化和砂岩铜矿成矿作用三者之间具有密切的关系,处于一个统一的系统之中。盆地早中期的裂陷、坳陷作用及热构造活动导致了富铜矿源层的形成、大气降水的深循环和水／岩相互作用、并形成中高温、压、高盐度的热卤水含铜流体。在构造－流体－砂岩铜矿成矿体系的演化中,构造演化制约了含铜流体的演化和砂岩铜矿的成矿作用,而主要发生于盆地演化的晚期。  相似文献   

目标函数聚类法在地下水动态分类中的应用   总被引：1，自引：0，他引：1  

孙才志  林山杉 《吉林地质》1999,18(2):50-55

地下水动态类型的划分是正确认识研究区水文地质条件与地下水开发利用之间关系的一个重要环节。本文论述了目标函数聚类法的原理与计算过程,并应用该方法对某河流附近的１５个观测孔的水位动态进行分类。分析结果表明该方法具有较高的可靠性与较广的适用性。  相似文献