共查询到20条相似文献，搜索用时 46 毫秒
1.
2.
大兴安岭铜山斑岩铜矿床位于中亚成矿域东段多宝山矿集区的东南部。前人对其进行了一些研究工作,但是针对其作为斑岩铜矿类型本身最重要标志的斑岩并未报道,且缺乏对该矿床基础矿床地质特征的详细研究。笔者在详细的野外工作、岩相学和矿相学工作的基础上,首次发现了该矿床的矿化斑岩,并将矿区的蚀变、矿化、脉系,划分出热液期和表生期:热液期包括以磁铁矿-钾长石-黄铁矿(Ⅰ)-黄铜矿-绿帘石-绿泥石为特征的热液活动早阶段,以石英-辉钼矿-黄铜矿-黄铁矿(Ⅱ)-少量闪锌矿-方铅矿及痕量斑铜矿为特征的主成矿阶段,以石英-方解石-黄铁矿(Ⅲ)为特征的热液活动晚阶段以及孔雀石-蓝铜矿及少量蓝辉铜矿为特征的表生期。根据镜下156个薄片中的蚀变矿物鉴定及含量统计,划分出1064勘探线剖面的蚀变矿物组合及分带;根据铜山断层上、下盘蚀变带的类型、组合、强度对比分析,推测热液蚀变成矿中心与斑岩体顶部大致位于ZK1064-2钻孔正下方1400 m深处,这为下一步深部找矿勘探提供了指导方向。 相似文献
3.
云南省龙陵县杨梅田铜矿为中温热液型铜矿床,铜矿体的分布宏观上受上奥陶统第2层底部层位的控制,主要产于构造破碎带中。在系统研究赋矿地层和矿床的元素组合、成矿成晕的轴向分带及叠加特征基础上,总结了深部盲矿预测的构造叠加晕标志;根据矿床成矿规律和探矿构造圈定有利成矿空间,结合构造叠加晕原理,在有利成矿空间上方坑道或钻孔中的前缘晕叠加部位圈定盲矿体预测靶区,并对定位预测的靶区进行工程验证。验证结果证明了构造叠加晕找盲矿法在热液型铜矿深部盲矿体定位预测的有效性。 相似文献
4.
青海铜峪沟铜矿床地质特征及形成机理 总被引：1，自引：0，他引：1
本文简要介绍了铜峪沟铜矿床地质概况,重点论述了“矿源层”的存在及其特征,认为区域变质作用促使了“矿源层”中成矿元素的活化转移,在变质水、变质热液的携带过程中以及有利的地层岩性和构造条件下富集成矿。本文运用地球化学成果、稳定同位素、包体成分和测温等资料论证了本区成矿物质和成矿溶液的来源,变质改造成矿期各阶段物理化学环境,讨论了变质热液的发生、发展、演化特征和改造成矿的机理,提出该矿床为沉积—变质热液改造层控型铜矿床。并在此基础上提出了新的矿床成因观点,建立了新的成矿模式。 相似文献
5.
6.
丽江东部地区广泛分布的黑泥哨组(P3h)是区域上一个重要的含铜层位,在该地区大公山、铜厂河、宝坪等地均发现有工业铜矿床。该地层中发现的铜矿床具有两种类型:产于火山沉积夹层中的火山沉积-热液型铜矿及产于构造破碎带中的构造热液型铜矿。主要控矿因素为二叠纪晚期古地理环境、火山活动、成矿前构造及喜山期岩浆活动。本文通过分析这些控矿因素之间的关系,总结该区域内黑泥哨组铜矿化规律,为今后的找矿工作提出一些建议。 相似文献
7.
山东省铜矿床类型、时空分布、典型矿床特征及成矿远景 总被引：1，自引：0，他引：1
山东省铜矿床的系统归纳和研究目前还没有,本文根据大量已有山东省铜矿的科研成果及国土资源储量利用现状大调查的部分成果,详细地分析了山东省铜矿资源基本状况、时空分布和不同矿床类型铜矿床特征。依据研究成果归纳总结划分出了斑岩型、矽卡岩型、似层状热液交代型、热液裂隙充填型、陆相火山岩型、基性超基性岩性6种铜矿床类型,其中,斑岩型、矽卡岩型、似层状热液交代型是山东省铜矿床的主要类型,其余类型多为其它矿种的伴生铜矿,中生代燕山期是山东省铜矿的主成矿期,并系统研究说明了每种矿床类型的典型矿区矿床特征,结合铜矿资源形成地质背景和时空分布特征及矿产资源规划,划分出了邹平-淄博、莱芜、沂南、五莲-胶南、栖霞-牟平-荣成等5个成矿远景重点勘查区域。 相似文献
8.
《西北地质》2020,(3)
杨屋场小型钨(金)矿床位于东秦岭杨斜-丰北河金钨成矿带东段。通过野外调查、岩矿鉴定及综合研究,查明了该矿床的地质特征与控矿因素,探讨了矿床成因,初步建立其"三位一体"找矿预测模型,可为杨斜地区钨金找矿提供一定的借鉴。研究表明,矿体赋存于商丹断裂带内北东—北北东走向的缓倾断裂,围岩为新元古代杨斜片麻岩套。矿石金属矿物为黄铁矿、黑钨矿、白钨矿、黄铜矿、闪锌矿、方铅矿及黝铜矿等中-高温组合。成矿过程包括热液成矿期与表生期,前者可划分为石英-细粒黄铁矿、石英-黑钨矿-白钨矿-多金属硫化物和石英-方解石-绢云母3个成矿阶段,围岩蚀变以硅化、黄铁矿化和白云母化为主。矿床的成矿作用受印支期花岗岩、断裂构造及围岩控制,成因应属于岩浆期后热液矿床。 相似文献
9.
四川省中厂铜矿位于扬子地台西南缘的康滇地轴中段,赋矿地层为中元古界下部的通安组,铜矿体赋存在通安组第二段和第三段中,铜矿体呈似层状,矿体围岩分别为白云石大理岩、石英变粒岩和含石英大理岩,地层中层间破碎带、滑动带和裂隙发育,并发生硅化、绢云母化、白云石化和褪色等热液蚀变,地层中碳质含量较高,矿床地质特征上判断,成矿经过沉积成岩期和构造-热液改造期,成矿物质为多期多来源,因此认为中厂铜矿床属于沉积-改造型铜矿床。 相似文献
10.
11.
CSAMT 法在辽西康杖子区深部探矿中的应用 总被引：5，自引：0，他引：5
可控源音频大地电磁法(CSAMT)具有探测深度大、横向分辨率高、抗干扰能力强的特点,在深部找矿勘探中有着重要的指导意义。肖家营子铜钼矿床是辽西地区一个大型矽卡岩型金属矿床,大部分矿体是隐伏矿体,矿区外围的康杖子区与本区有相似的成矿地质环境,成矿地质条件优越.矿体与围岩电性差异明显,通过应用CSAMT,矿体具有低电阻特点,根据成果推断解释,对深部有利成矿部位进行了钻探验证,取得了理想的探矿效果,在矿区外围取得第二深度空间找矿重大突破。 相似文献
12.
13.
Julie Okpala 《GeoJournal》1990,20(1):37-43
This paper traces the development of geographic education in Nigeria and examines the views of geographers, other academics,
students and the public at large about the importance of geography. Geography's value is immense despite the non-professional
nature of the discipline. Nevertheless, there is a need to define geography's status and ensure career prospects for students.
The Nigerian Geographical Association (from classroom teaachers to top geographers) must promote geography, improve its status
in schools and universities, and continuously restructure its content and methods to address pertinent social needs. 相似文献
14.
Trends in landslide occurrence in Nepal 总被引：2，自引：0，他引：2
David N. Petley Gareth J. Hearn Andrew Hart Nicholas J. Rosser Stuart A. Dunning Katie Oven Wishart A. Mitchell 《Natural Hazards》2007,43(1):23-44
Nepal is a mountainous, less developed kingdom that straddles the boundary between the Indian and Himalayan tectonic plates.
In Nepal, landslides represent a major constraint on development, causing high levels of economic loss and substantial numbers
of fatalities each year. There is a general consensus that the impacts of landslides in countries such as Nepal are increasing
with time, but until now there has been little or no quantitative data to support this view, or to explain the causes of the
increases. In this paper, a database of landslide fatalities in Nepal has been compiled and analysed for the period 1978–2005.
The database suggests that there is a high level of variability in the occurrence of landslides from year to year, but that
the overall trend is upward. Analyses of the trends in the data suggest that there is a cyclicity in the occurrence of landslide
fatalities that strongly mirrors the cyclicity observed in the SW (summer) monsoon in South Asia. Perhaps surprisingly the
relationship is inverse, but this is explained through an inverse relationship between monsoon strength and the amount of
precipitation in the Hill District areas of Nepal. It is also clear that in recent years the number of fatalities has increased
dramatically over and above the effects of the monsoon cycle. Three explanations are explored for this: land-use change, the
effects of the ongoing civil war in Nepal, and road building. It is concluded that a major component of the generally upward
trend in landslide impact probably results from the rural road-building programme, and its attendant changes to physical and
natural systems. 相似文献
15.
2010年,美国铀矿总共施工7 209个钻孔,总进尺1 493 520 m;生产铀1 628.55 t;铀矿业总支出费用为2.773亿美元,其中铀矿地勘费支出为3 450万美元,占铀矿业总费用的12.44%。铀矿地勘钻探费用为4 460万美元,占铀矿业总费用的16.08%。 相似文献
16.
硫代砷是富硫化物地下水中砷的重要形态,对环境和人类健康有潜在威胁。目前硫代砷研究程度尚低,本次主要针对国内外地下水（地热水）中硫代砷的存在形态,水文—生物—环境地球化学过程,样品保存,定量检测方法等方面进行研究。结论如下:pH, 氧化还原电位,硫化物含量和微生物作用等是影响地下水中硫代砷稳定存在和形态分布的重要因素。含铁矿物能与水中的硫代砷形成配位键对其进行吸附,吸附性普遍弱于（亚）砷酸盐,因此,地下水中硫代砷可能表现出更强的迁移性。用于硫代砷检测的自然水样在采集中可采取过滤,速冻,厌氧和低温短期保存的操作流程,以减缓该形态的转化甚至消失。色谱联用ICP-MS系统可用于自然水样中硫代砷的分离定量检测,紫外—可见分光光度法和X射线吸收光谱法在不同场景下也可对硫代砷进行定量和表征分析。地热水和浅层地下水中均可能存在硫代砷,由于水样中硫代砷的不稳定性,室内检测和分析难以准确反映现场过程,因此,野外样品保存技术和现场检测方法的更新可能在未来有更大研究空间,值得进一步探索。 相似文献
17.
18.
Takeshi Nose Dr. 《GeoJournal》1985,10(3):261-276
Conclusions During the last ten years, aquaculture, especially mariculture has undergone remarkable expansion to counter-balance the gap between the supply and demand of fishery products in Japan. Its expansion has also been supported by the traditional preference of the Japanese people for seafood. Mariculture is now being forced to change its structure due to adverse economic circumstances such as the rise in the cost of energy, feeds and other materials for culture, low market prices, deterioration of environmental conditions, and many other factors. Before these constraints can be resolved, advanced scientific knowledge and technologies must be integrated to develop new types of aquaculture. Expansion of maricultural activities to more open-sea and off shore areas would be one route to follow. Technologies for the development of formulated diets not only for young but also for adults and larvae, establishment of feeding standards, prevention of epizootic diseases must support the establishment of modern aquaculture.The culture-based fisheries, or marine ranching, is becoming a subject for further development in Japan. Much research work has been conducted with a great degree of governmental support. Establishment of a net work of seedstock production farms has made it possible to carry out releasing experiments on a large scale. A newly integrated restoration system could be developed on the basis of these experiments, even though the profits resulting from the artificial restoration of stocks is not thouroughly verified at present. The commencement of a national scheme for culture-based fisheries would be a manifestation of the enthusiasm of the Japanese fish industry. 相似文献
19.
Radon is a radioactive gas emanating naturally from uranium rich granites and shales. It may be emitted from the ground surface into the atmosphere as a gas, or it may be dissolved into stream water and transported over distance. The levels of radon gas in soils at ground surface depend on a number of factors relating to the source of the gas and to its transmission. Igneous rocks contain the highest mean concentrations of radium and uranium. The depth of cover is relevant also. Surveys over the years by the National Radiological Protection Board (NRPB) and others have indicated that the highest concentrations in the United Kingdom occur in Cornwall, Devon and northeast Scotland. However, recent reports have indicated that high concentrations of the gas may be detected in small pockets in counties outside of those considered at high risk. This survey relates to a series of measurements taken in and around Darlington, County Durham. The results showed the presence of small areas with strong concentrations of radon in soil gas, but only minor levels of dissolved gas in stream waters. 相似文献
20.
内蒙古苏尼特地下水氟污染形成机理研究 总被引：4，自引：1，他引：3
为了研究内蒙古苏尼特地区地下水氟污染机理,本文运用水文地球化学分类方法,从水文地质、水化学特征两方面研究其地下水的水质特征、氟的起源、分布规律及污染形成机理。研究结果发现:高氟地下水的主要水质类型为HCO3—Na型,pH值在7.08～9.38之间,氟浓度与井深有关,即井越浅,氟浓度越高;地下水中氟浓度最高达14.78mg/L,5～9月地下水氟浓度相对增长率在7.8～23.1之间;F-浓度与Li+、Br-相关系数达0.89和0.82,受断层影响的深层地下水中F-浓度几乎与Li+、Br-没有相关关系,这暗示着氟来源于浅部,并受到强烈的蒸发作用影响而使水中的氟浓缩;地质调查发现该地区还有数个萤石矿存在,显微镜分析结果证实表层土壤中普遍存在CaF2,地下水中的氟来自CaF2。高氟地下水存在于潜水层,深部含水层的地下水可供开采。从断层带涌出的水对潜水层有稀释作用。 相似文献