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研究区为鲁西地区重要的成矿带——东平—汶上铁矿带,该铁矿带内已探明彭集、张家毛坦、化肥厂等多个大中型铁矿床,说明该成矿带具备优越的成矿地质条件及良好的找矿潜力。通过剖析近年来区内典型矿床的最新勘查成果,从矿床控矿地层、成矿时代、成矿物质来源、矿化阶段、矿体特征及物探异常等8个方面进行系统分析,开展了铁矿成矿规律研究;根据东平—汶上铁矿带的成矿时代、赋矿层位、含铁建造及岩石组合,结合成矿规律的分析,初步建立了"东汶式"铁矿床成矿模式。 相似文献
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山东省东平-汶上铁矿成矿带是鲁西重要的成矿带,区内已发现李官集、彭集等多个大中型铁矿床,探明了铁矿石资源量超过12亿t。通过收集东平-汶上地区基础地质调查、区域重磁、矿产勘查、科研成果等资料,分析了区内地层、构造、岩浆岩及区域航磁异常特征、重力异常特征与铁矿床的对应耦合关系,提出了矿床的3个控矿因素:即控矿地层(泰山岩群雁翎关组、山草峪组,地层控矿专属性)、控矿构造(同斜复式背斜构造)、控矿岩浆岩(改造和破坏了铁矿带的完整性),通过对成矿区带样品采集测试,分别从主量元素、稀土元素、微量元素、原岩恢复、变质岩构造背景等方面进行系统分析对比,探讨了该区铁矿床为海相岛弧火山——沉积变质成因。 相似文献
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研究区位于鲁西地区重要的东平—汶上铁矿带西侧,为低缓磁异常区。通过高磁测量、井中三分量磁测、钻探验证等手段,在梁山李官屯附近低缓磁异常区发现铁矿一处,矿床类型为条带状铁建造(BIF)型铁矿。该区下伏地层主要为新太古代泰山岩群山草峪组,岩性为黑云变粒岩,局部夹磁铁石英岩、磁铁角闪石英岩,矿石的主要组成矿物为磁铁矿、黄铁矿、黄铜矿。研究区山草峪组大面积分布,根据成矿时代、赋矿层位、含铁建造及岩石组合,结合成矿规律研究分析,梁山地区的大面积条带状分布的低缓磁异常区是寻找隐伏铁矿体的有利部位。 相似文献
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单县铁矿是近年来在鲁西南地区查明的典型铁矿床之一;该铁矿位于巨厚覆盖层下,其地质特征、地球物理特征、矿床特征和矿体特征等方面均已查明,但成矿时代一直没有精确的定年数据支持。该次研究工作对单县含铁建造中的黑云变粒岩进行锆石SHRIMP U-Pb测年,测年结果显示该含铁建造形成于(2 503±6)Ma、(2 512±6)Ma,属新太古代晚期。通过与鲁西地区相关铁矿地质特征对比研究认为,单县铁矿与苍峄铁矿带、东平-汶上铁矿带的含矿建造相同,其赋矿地层为新太古代泰山岩群山草峪组,均属"苍峄式"沉积变质型铁矿。由于该山草峪组含矿建造在鲁西隆起区内广泛分布,通过对区内地质特征和物探异常的对比进行选区研究,利用单县地区铁矿的勘查经验并选取有效的勘查技术手段,有望在周邻地区的巨厚覆盖层下发现新的铁矿找矿靶区。 相似文献
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通过对太行山南段平顺铁矿矿区构造特征及岩浆岩的动力学分析研究,认为第一岩浆岩带属于被动侵位机制,岩体内部成矿潜力较大;第二岩浆岩带为主动侵位机制,背斜核部及岩体与围岩的接触部位为有利成矿区。同时根据岩石、矿石的稀土元素、微量元素、Pb同位素特征及矿体与岩体的关系,认为晚期闪长岩是主要的成矿母岩,但早期基性—超基性岩间接为铁矿的形成提供了一定的物质来源;矿体的形态明显受到接触面及周边构造形态的控制,呈不规则板状、透镜状、分枝状、羽状分布。最后运用矿体成矿规律、磁异常、电法异常等找矿预测方法,在研究区内圈出了龙降沟岩体南缘、双井、东郊3个找矿预测区。 相似文献
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塔儿山-二峰山地区基岩山区铁矿资源已呈枯竭之势,为使老的成矿远景区取得新的找矿成果,铁矿找矿方向应转向新生界覆盖区的低缓磁异常.结合近年来某些磁异常的验证见矿,说明原来验证不彻底或现在看来验证结论不完全正确的异常可能是矿致异常.所以"攻深找盲"首选大王成矿段、万户-老官庄异常段和丹山-绵山-秦岗隆起成矿段,以高精度磁测和大工作量的钻探进行验证. 相似文献
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王明远 《中国地理科学(英文版)》1993,3(4):376-380
We have made progress in medico-chemical geography as follows: the correlative law of organism with geochemical environment; the geochemico-ecological classification of chemical elements; the types of formative cause of biogeochemical provinces in China; the parabolic correlation between contents of iodine in drinking water and prevalence rate of endemic goiter; the discovery and proof of the low selenium zone in China; the successive discovery of endemic fluorosis of the types of pollution from burning coal, drinking high fluoride tea and high fluoride table salt from the year 1978; the study on chemical geography of schistosomiasis and the compilation of the Atlas of Endemic Diseases and Their Environments in the People's Republic of China. 相似文献
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随着信息社会的发展，新技术和新媒体的出现必然影响学校现代教育的发展。通过阐述发展学校电化教育的应注意的问题，探讨了解决问题的方法。 相似文献
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We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou Bay, China. Zooplankton samples were vertically towed with conical plankton net from near-bottom to surface, identified microscopically, and mapped in time-space using Grapher 7.0 and Surfer 8.0. Results show that the abundance of small-jellyfish throughout the bay had been increasing during 2001-2009 on average of 15.2 ind./m 3 , almost 5 times higher than that between 1991 and 2000. The occurrence of peak abundance shifted from spring to summer after 2000, and two peaks appeared in spring and summer, respectively, after 2005. Both the abundance and the frequency of blooms of small-jellyfish increased after 2000 in the bay. In addition, the biodiversity of jellyfish has increased significantly in recent years with a change in dominant species. Several new dominant species appeared after 2000, including Rathkae octopunctata in winter, Phialidium hemisphaericum in spring, summer, and autumn, Phialucium carolinae in spring, and Pleurobrachia globosa in summer and autumn, while some previous dominant species throughout the 1990s (Eirene ceylonensis, Zanclea costata, Lovenella assimilis, and Muggiaea atlantica) were no longer dominant after 2000. The abundance of small-jellyfish was positively correlated with the density of dinoflagellates, and the abundance of zooplankton. We believe that the changes in smalljellyfish abundance and species composition were the result of eutrophication, aquaculture and coastal construction activities around the bay. Concurrently, seawater warming and salinity decrease in recent decades promoted the growth and reproduction of small-jellyfish in the bay. 相似文献
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Community Participation in Forest Resource Management in Nepal 总被引：2，自引：1，他引：1
KeshavL.Maharjan 《山地科学学报》2005,2(1):32-41
Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such as energy for cooking, nutrition for animals, materials for fertilizer and constructing materials for shelter, are limited. Thus, the well being of the people in the hills is directly affected by the management of these forest resources. This issue was addressed in this paper by examining the forest resource management practices and its effect on well being of rural people in two different stages in a village lying in the steep hill of Mahabharat Range in the southern hills of Kathmandu valley, Lalitpur District. The main ethnic/caste groups in the villageare Brahmin/Chhetri (high Hindu caste),Magar/Tamang (Tibeto Burmans) and Kami (occupational caste: cobbler). Currently there are four community forest users groups, with mixed ethnic membership, organized to manage the forest resources. The endowments, weak institutional settings, before 1990 helped the Bhramins, Magars and Tamangs to get access into the private forest endowment, which made them easy to get access to the forest resources, mainly fuel wood, fodder and timber in 1990 and enhanced their well beings. But the socially backward Kami could not get benefit from the institutions that existed during that time and had less chance to enhance their well beings. After the set up of different endowments during late 199os, i.e.,hand over of forest management to users groups in line with the concept of community forest,environment to use the forest resources became better for all the groups, along with the management of the forest. This enhanced the well beings of all the groups in the study village. However, the ability of Kami to use the forest resources to enhance their well beings was still lacking behind. The reason was partially due to the difference in endowments carried over from the endowments before 199o, and partly due to their occupational work and location of their settlements. 相似文献
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浅析高校国有资产管理存在的问题及解决的措施 总被引：4，自引：0，他引：4
高校国有资产管理是学校管理工作的重要组成部分，加强高校国有资产管理已经成了国家有关部门和高校管理人员普遍关注的问题，文章从高校国有资产管理中存在的问题入手，剖析其成因并提出解决的措施。 相似文献