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21.
Graphite is one of the most essential non-metallic minerals with a wide variety of uses, and is an important commodity used in the emerging industry of China. Graphite is sourced from 170 mine areas in China from 25 provinces. This contribution is on a study of 15 regions in China with known graphite resources based on the spatial and temporal analyses of the regional metamorphic, contact metamorphic, and hydrothermal types of graphite. The knowledge gained on the metallogenesis of graphite in China is used to develop a model for choosing prospective regions for graphite, and to target areas for detailed exploration. It outlined 28 prediction areas with predicted graphite resources of about 1.63 billion tonnes to a maximum depth of 500 m in the Heilongjiang, Jilin, Liaoning, Shandong, Inner Mongolia and Hunan provinces. And of these, the predicted flake graphite resources in the Heilongjiang Province has been totalling almost a billion tonnes representing almost 60% of China’s graphite resource. As a result of this study, it is concluded that graphite has been formed during restricted periods of time, with the regional metamorphic type being the main style present in China.  相似文献   
22.
中国南方含油气区构造-沉积类型及其勘探潜力   总被引:1,自引:0,他引:1  
南方含油气的复杂构造区根据构造—沉积类型的不同,可将其分为四种类型。通过对不同类型典型含油气区的生烃量及非构造运动天然气散失量的化学动力学计算,认为这四种类型含油气区的油气聚集潜力从好到坏依次为:喜马拉雅运动抬升暴露型、燕山运动抬升暴露型、反复抬升—沉降型和海西—印支运动抬升暴露—后期浅埋型。主要构造运动发生越晚,对油气保存越有利。  相似文献   
23.
赵子欧  乔东海  赵元艺 《岩石学报》2020,36(9):2785-2798
位于西藏多龙矿集区的荣那铜金矿床是班公湖-怒江成矿带首例斑岩型-浅成低温热液型矿床,它的发现对于班公湖-怒江成矿带找矿模型的构建以及资源潜力评估有着重要意义。本文以荣那矿床ZK3204岩芯钻孔为研究对象,针对其蚀变矿物,运用短波红外光谱测试技术,并结合金属矿物组合以及黄铁矿LA-ICP-MS原位微量元素特征,以期查明其矿床成因,并为深部资源勘查提供理论依据。短波红外光谱测试显示出ZK3204钻孔蚀变矿物垂向分带组合为:高岭石+(地开石)→高岭石+伊利石→高岭石+(地开石+石膏)→高岭石+绢云母+伊利石→高岭石+伊利石+(叶腊石)+(地开石),金属矿物也从Cu-S体系逐渐转变为Cu-Fe-S体系。通过黄铁矿LA-ICP-MS原位微量元素分析发现,黄铁矿可分为四类,分别对应荣那矿床四个成矿阶段:(1) Py I:Co、Ni、Cu、Ag、Au含量较低,Co/Ni显示为沉积成因,代表成岩期黄铁矿;(2) PyⅡ:Co、Ni含量较低,Cu、Ag、Au含量较高,Co/Ni显示为沉积成因,代表第一期斑岩型矿床成矿期黄铁矿;(3) PyⅢ:Co含量较低,Ni、Cu、Ag、Au含量较高,Co/Ni显示为沉积成因,代表第二期斑岩型矿床成矿期黄铁矿;(4) PyⅣ:Cu、Ag、Au含量较低,Co、Ni含量较高,Co/Ni显示为热液成因,代表浅成低温热液矿床成矿期黄铁矿。风化作用也是荣那矿床重要地质过程,贯穿于各成矿阶段,反映为早白垩世班公湖-怒江洋盆向北俯冲消减大背景下的多龙矿集区隆升事件,导致矿床被大量剥蚀,也使黄铁矿显示沉积成因。荣那矿床目前仍有较大找矿潜力,在钻孔深部(815m以下),黄铁矿Cu、Ag、Au含量,钻孔中Cu、Pb、Zn、Cr、Hg等含量,绢云母、伊利石含量以及铜金矿的矿石品位均有向下升高的趋势,说明在ZK3204钻孔下部仍有巨大的找矿潜力,可作为未来深部资源探测的重点对象。  相似文献   
24.
Dongying City, which is the most important central city in the Yellow River Delta, is located in the estuary of the Yellow River. With a short land formation time, ecological environment is very weak in this area. To realize the sustainable economic development of the Yellow River Delta, resource environment and resource environmental bearing capacity (REBC) must be improved. This study builds assessment system of regional REBC through resource and economic characteristics in Yellow River Delta and uses principal component analysis (PCA) method to evaluate REBC of five counties and districts in Dongying City in 2011-2015 on the dimensions of time and space. Results show that, on the time dimension, Guangrao County is ranked first, Dongying district second for four years and Hekou and Kenli districts with lower ranks in 2012-2015, indicating that more attention needs to be paid to REBC of Hekou and Dongying districts and these two districts should be included into key monitoring areas. From space scale, REBC in five counties and districts has been gradually improving. In order to further develop REBC in Dongying City, measures such as intensifying protection of urban ecological environment and developing circular economy, etc. should be implemented.  相似文献   
25.
Thembela Kepe 《Geoforum》2008,39(2):958-968
Different types of vegetation found in local environments are of value to rural livelihoods of many African households. However, the dominant way of expressing this value, which is mainly through economic valuation studies, is potentially limiting this knowledge’s usefulness in policy and research, due to the inability to present full picture. Using literature review and insights from field work, the paper argues that realized and notional values of vegetation to rural livelihoods are socially constructed and contested, and - in addition to understanding local livelihood context, which include social difference, and ecological dynamics - a focus on social institutions as terrains of negotiation is crucial. This means that resource value in rural livelihoods can be realized through contested and negotiated access arrangements that are mediated by complex institutions at local and external levels.  相似文献   
26.
Geographical Conditions and National Strategies   总被引:3,自引:0,他引:3  
This paper is a summary based on the relationship between national conditions and development strategies for decades of consulting research. Through cases, the paper outlined the basic meaning of national conditions and geographical conditions and their close relationship with national development strategies, and emphasized the importance of comprehensive thinking and scientific judgment in the process of carrying out the governments’ strategies and development policies, and making development policies. At last, suggestions were made that the points of China’s national conditions and the rules of connection with government decision-making should be written into geography textbooks as well as into textbooks for party schools of the Communist Party of China.  相似文献   
27.
资源安全供应是保障国民经济持续健康发展的必要条件。阐述了发达国家资源安全供应的3个模式:比较优势模式、贸易一投资模式和系统论模式。通过实例,就模式的作用机理进行了简要分析。结合我国的实际情况,借鉴发达国家资源安全供应的经验,就我国资源的安全供应提出了4个方面的建议。  相似文献   
28.
运用神经网络模型的一典型模型——“反向传播”模型的改进形式,处理矿产资源统计预测问题,得出与数量化理论Ⅱ处理极为相似的结果.  相似文献   
29.
根据两次资源评价结果的分析和对比,认为值得对古生界进行大规模油气勘探。分析了中国海相油气勘探滞后的原因是地史发展的顺序为先海后陆和海相沉积深度比陆相的大。归纳阐述了适用于海相沉积与陆相沉积的10条基本石油地质认识,指出了我国海相沉积深度大、年代老、生油争议多、气比油多、遭破坏多等特点,建议开展区域地质、碳酸盐岩生油、古隆起带、逆掩断层带、盐下油气、碳酸盐岩储集性、油藏破坏与保存的关系、新技术与新方法等8个方面的研究。  相似文献   
30.
云南羊拉铜矿三维地质建模及储量计算   总被引:1,自引:0,他引:1       下载免费PDF全文
孙潇  陈建国  房晓龙 《江苏地质》2012,36(3):326-332
以云南羊拉铜矿的断层、地层、岩体、矿体为研究对象,在分析研究建模技术方案的基础上,依据收集到的钻孔柱状图、勘探线剖面图、中段地质图和地形地质图,结合野外踏勘与认识,利用Micromine软件建立了研究区的地形、地层、断层以及矿体的三维实体模型,直观展示了区内地表、断层、地层、岩体以及矿体的空间展布以及相互的空间位置关系。运用克里格法对里农矿段的铜矿体进行品位估值,获得了矿体的储量。  相似文献   
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