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91.
Xu Butai Li Changjiang Zhejiang Institute of Geology Mineral Resources Hangzhou Zhejiangand Chen Haoshou Department of Earth Sciences Zhejiang U niversity Hangzhou Zheyang Liu Xinzhu 《《地质学报》英文版》1995,69(1):69-83
In the Xinchang-Yongjia silver (lead-zinc) ore belt, there mainly occur the large to medium-sized Haoshi, Bamao, Dalingkou and Wubu silver deposits or silver-bearing lead-zinc deposits. On the basis of researches on these typical deposits, the mechanism of leaching-drawing mineralization of Mesozoic geothermal water and the related model are put forward in this paper in the light of the time interval between rock and formation ages as well as hydrogen, oxygen, sulphur and lead isotope geochemical characteristics. The major metallogenic process occurred in volcanic rock layers. The ore-forming fluids are geothermal water coming from meteoric water and circulating at shallow layers. This geothermal water leached and absorbed ore-forming materials from its country rocks during its flowing (such metallogenic elements as silver, lead-zinc and sulphur mainly came from consolidated volcanic rocks), leading to the formation of meso - epithermal silver deposits. 相似文献
92.
浙江渡船头“伊利石”应属绢云母 总被引:1,自引:0,他引:1
渡船头云母状矿物长期以来被称为“伊利石”,近期经过X射线衍射(XRD)、红外光谱(IR)、差热分析(DTA)、电子显微镜(EM)观察及化学组成等研究后显示:这种呈薄鳞片状、粒度很细(一般小于5μm)、结晶度高的矿物,其d(002)=9.95?,为2M多型,出现特征的3625cm~(-1)、3450cm~(-1)、1020cm~(-1)、935cm~(-1)、825cm~(-1)、799cm~(-1)、755cm~(-1)、543cm~(-1)、480cm~(-1)红外吸收和40—70℃、106.4—111.2℃两弱吸热谷及630—670℃强吸热谷;矿物MgO小于0.25%,结构中八面体Mg~(2+)量小于0.03,以Al~(3+)和Fe~(3+)为主,八面体电荷为-0.052—+0.048/O_(10)(OH)_2,K_2O一般大于9%。上述这些均表明,渡船头“伊利石”应属绢云母。 相似文献
93.
柴达木盆地西部地区古近系和新近系湖相碳酸盐岩主要分布于下干柴沟组上段到油砂山组,其中,下干柴沟组上段和上干柴沟组的碳酸盐岩更发育。碳酸盐岩主要岩石类型有泥晶灰岩、藻灰岩和颗粒灰岩等三大类,此外,还普遍发育由石灰质、白云质和陆源碎屑等3种组分构成的混积岩。碳酸盐岩沉积相可划分为滨湖灰泥坪、滨湖藻坪、浅湖颗粒滩、浅湖藻丘以及半深湖泥灰岩相。滨湖灰泥坪的主要岩石类型有泥晶灰岩、含陆屑泥晶灰岩、陆屑泥晶灰岩以及陆屑泥灰岩等;滨湖藻坪为藻泥晶灰岩、藻纹层灰岩、含陆屑藻泥晶灰岩;浅湖颗粒滩有亮晶或泥微晶的鲕粒灰岩、生屑灰岩和内碎屑灰岩,其次为含陆屑颗粒灰岩;浅湖藻丘为藻叠层灰岩、藻团块灰岩、藻泥晶灰岩和含陆屑藻泥晶灰岩;而半深湖泥灰岩相的主要岩石类型为泥晶灰岩、泥灰岩以及含少量陆屑泥和粉砂的泥晶灰岩或泥灰岩。碳酸盐岩沉积相表现出很强的由西南向东北的迁移性。 相似文献
94.
HAN XiQiu QIU ZhongYan MA WeiLin & QIAN JiangChu Key Laboratory of Submarine Geosciences State Oceanic Administration Hangzhou China Second Institute of Oceanography 《中国科学D辑(英文版)》2009,(4)
Due to their slow growth rates, seamount Co-rich crusts are very difficult to date with high resolution and precision. This paper is to test the use of orbital pacing on the growth profile of crusts to determine high-resolution age and growth rate. Crust CB14 from the central Pacific Ocean was selected for this study. We first examined the growth pattern in detail under a reflected-light microscope and ascertained that the growth environment was stable for the sub-layer 1 (0-3 mm). We then used electron mic... 相似文献
95.
Fractal Principle of Mineral Deposit Size Forecasting and Its Implication for Gold Resource Potential Evaluation in China 总被引:1,自引:0,他引:1
LI Changjiang MA Tuhu ZHU Xingsheng WANG Guowu Zhejiang Institute of Geology Mineral Resources Hangzhou Zhejiang Earth Science Department Zhejiang University Hangzhou Zhejiang Zhejiang Bureau of Geology Mineral Exploration Development Hangzhou Zhejiang 《《地质学报》英文版》2002,76(3):378-386
Mineralization distributions are very heterogeneous in nature. As large or superlarge mineral deposits are quite rare whether in time or in space, it is difficult to detect all the largest mineral deposits in a region in a limited period of time owing to the restriction of technology and exploration degrees-this is called "not all discovered". However, all discovered large, especially superlarge, mineral deposits generally have a complete census in the geological literatures. On the other hand, not all discovered small mineral deposits are recorded in the geological literatures because for economic reasons people have not much interest in them-this is called "not all recorded". This practice often results in the observation truncations, that is, the data points near the two ends in an observable population, which is obtained by fitting a power law size-frequency distribution to discovered mineral deposits in a given region, show concave-down departure from the correlation line fitted. The authors sugges 相似文献
96.
为提高市场竞争力,根据自身的特点,认真研究市场信息,抓准项目,是地勘单位承办 企业的基础。工作中重视人力资源的开发和合理配置,建立切实可行的管理制度,在管理工作中 综合运用多种激励机制,就可使企业在激烈的市场竞争中立于不败之地。 相似文献
97.
随着水体富营养化程度的加剧,淡水蓝藻水华在全球范围内频繁暴发.拟柱孢藻(Cylindrospermopsis raciborskii)作为一类有害水华蓝藻,具有一定的产毒能力和较强的入侵性,日渐受到人们的广泛关注.近年来,拟柱孢藻不断由热带、亚热带地区向温带地区扩张,并在众多水体中出现暴发现象,若其毒素进入到饮用水中,无疑将对人类健康造成潜在威胁.本文从拟柱孢藻的分布演变、生态生理特征、毒性、检测和去除等研究前沿方面进行了综述,并对相关研究领域进行展望,为进一步研究拟柱孢藻的生态毒理、有效控制和去除提供科学依据. 相似文献
98.
深海微生物培养模拟平台温度控制技术研究 总被引:3,自引:0,他引:3
针对深海微生物培养系统对温度条件的苛刻要求,在分析系统构成及建模的基础上,介绍了一种对系统的两级滞后环节采用了PI控制和双Smith预估反馈的方法,通过内环和外环Smith预估控制,精确的消除了温度控制系统中滞后延迟环节的影响,提高了PI控制强度,减少了超调,提高了系统动态响应和稳态精度。在系统Matlab仿真和实际实验中得到了良好的效果,满足系统的精度要求。 相似文献