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801.
简单介绍了502脉成矿特征,分析了502脉Au及其相关元素原生岩石地球化学异常特点,并根据各元素异常对金矿床的不同指示意义及其空间变化趋势,结合元素轴向分带序列的研究结果,推断5024脉1873m中段以下部位有较好成矿远景。 相似文献
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Avriel Venis L. Cirineo Akira Imai Ryohei Takahashi Redempta P. Baluda Noel C. Oliveros Victor B. Maglambayan Roy Ronald C. Luis Maria Lourdes M. Faustino Jacky Almadin 《Resource Geology》2021,71(1):1-40
The Southwest prospect is located at the southwestern periphery of the Sto. Tomas II porphyry copper–gold deposit in the Baguio District, northwestern Luzon, Philippines. The Southwest prospect hosts a copper‐gold mineralization related to a complex of porphyry intrusions, breccia facies, and overlapping porphyry‐type veinlets emplaced within the basement Pugo metavolcanics rocks and conglomerates of the Zigzag Formation. The occurrences of porphyry‐type veinlets and potassic alteration hosted in the complex are thought to be indications of the presence of blind porphyry deposits within the Sto. Tomas II vicinity. The complex is composed of at least four broadly mineralogically similar dioritic intrusive rocks that vary in texture and alteration type and intensity. These intrusions were accompanied with at least five breccia facies that were formed by the explosive brecciation, induced by the magmatic–hydrothermal processes and phreatomagmatic activities during the emplacement of the various intrusions. Hydrothermal alteration assemblages consisting of potassic, chlorite–magnetite, propylitic and sericite–chlorite alteration, and contemporaneous veinlet types were developed on the host rocks. Elevated copper and gold grades correspond to (a) chalcopyrite–bornite assemblage in the potassic alteration in the syn‐mineralization early‐mineralization diorite (EMD) and contemporaneous veinlets and (b) chalcopyrite‐rich mineralization associated with the chalcopyrite–magnetite–chlorite–actinolite±sericite veinlets contemporaneous with the chlorite–magnetite alteration. Erratic remarkable concentrations of gold were also present in the late‐mineralization Late Diorite (LD). High XMg of calcic amphiboles (>0.60) in the intrusive rocks indicate that the magmas have been oxidizing since the early stages of crystallization, while a gap in the composition of Al between the rim and the cores of the calcic amphiboles in the EMD and LD indicate decompression at some point during the crystallization of these intrusive rocks. Fluid inclusion microthermometry suggests the trapping of immiscible fluids that formed the potassic alteration, associated ore mineralization, and sheeted quartz veinlets. The corresponding formation conditions of the shallower and deeper quartz veinlets were estimated at pressures of 50 and 30 MPa and temperatures of 554 and 436°C at depths of 1.9 and 1.1 km. Temperature data from the chlorite indicate that the chalcopyrite‐rich mineralization associated with the chlorite–magnetite alteration was formed at a much lower temperature (ca. 290°C) than the potassic alteration. Evidence from the vein offsetting matrix suggests multiple intrusions within the EMD, despite the K‐Ar ages of the potassic alteration in EMD and hornblende in the LD of about the same age at 3.5 ± 0.3 Ma. The K‐Ar age of the potassic alteration was likely to be thermally reset as a result of the overprinting hydrothermal alteration. The constrained K‐Ar ages also indicate earlier formed intrusive rocks in the Southwest prospect, possibly coeval to the earliest “dark diorite” intrusion in the Sto. Tomas II deposit. In addition, the range of δ34S of sulfide minerals from +1.8‰ to +5.1‰ in the Southwest prospect closely overlaps with the rest of the porphyry copper and epithermal deposits in the Sto. Tomas II deposit and its vicinity. This indicates that the sulfides may have formed from a homogeneous source of the porphyry copper deposits and epithermal deposits in the Sto. Tomas II orebody and its vicinity. The evidence presented in this work proves that the porphyry copper‐type veinlets and the adjacent potassic alteration in the Southwest prospect are formed earlier and at a shallower level in contrast with the other porphyry deposits in the Baguio District. 相似文献
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城市空间意象为解释城市中居民与城市环境相互作用提供了重要研究视角,对城市空间管理与环境规划具有重要的实践指导价值。对国内外相关文献的查阅和分析显示,国外学术界对城市空间意象的研究比较深入,在理论和实践上都有许多成果,而国内的相关研究才刚刚起步。从研究的学科视角、核心内容、热点与重点、研究方法等四个方面来看,国内外城市空间意象研究有所异同。在此基础上,本文从城市空间意象特征的动态分析和对比分析、城市意象空间营造的理论与方法问题等层面提出了未来深入研究的方向,希望对国内城市空间意象研究有所启示。 相似文献
807.
旧县地区位于东平县城区西北部,东平湖的东北部。隐伏发育泰山岩群山草峪组黑云变粒岩、斜长角闪岩、条带状磁铁角闪石英岩等,是铁矿体的主要赋矿层位。发育2条NNW向断裂构造,岩浆岩仅分布有新太古代傲徕山序列条花峪单元和中生代沂南序列铜汉庄单元。研究区位于汶上东平阿城NW向区域航磁测带的北段,磁场等值线分布比较均匀,规律性较好,以东、北、西侧为低背景,中、南部相对较高,圈定1处走向NW—SE近椭圆形异常,发现2个铁矿体。矿体呈层状赋存于新太古代泰山岩群山草峪组中下部,为沉积变质型铁矿,赋矿岩石为条带状磁铁石英岩、角闪磁铁石英岩。 相似文献
808.
我国重要有色金属资源——铜矿的现状及展望 总被引:3,自引:0,他引:3
铜及其合金材料被广泛地应用于电子工业、机器制造、军事工业、农业等经济领域,是现代工业、农业、国防和科学技术必需的金属材料。铜在自然界中,主要呈硫化物及其类似化合物和铜的氧化物、自然铜以及铜的硫酸盐、碳酸盐、硅酸盐等类型矿物存在,已发现约有280多种,其中主要矿物16种。铜矿石的自然类型一般按物相分析中含氧化矿和硫化矿的比例不同,分为硫化矿石(含氧化铜在10%以下)、混合矿石(含氧化铜10%~30%)和氧化矿石(含氧化铜在30%以上)3种。我国铜矿主要分布在江西、云南、湖北、西藏、甘肃、安徽、山西、黑龙江等省,具有以下特点:(1)矿床规模小。(2)共生伴生矿多,品位低。(3)适合采用浸出-萃取-电积工艺的斑岩型铜矿少,降低生产成本的空间受到限制。(4)剩余储量中规模大、品位高的矿床多处于边远地区,外部建设条件差,在目前的金融、财税政策下,难以开发利用。总体上,我国铜矿资源在数量和品位等方面均比较差,其国际竞争力低,铜资源特别是富铜资源不足,已是不争的事实。近十余年来我国铜矿保有储量总体上处于一个相对平稳的状态,即新增探明储量和矿山消耗储量大体平衡。我国快速增长的铜消费主要靠进口解决。 相似文献
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应用地气、X荧光、氡气测量方法识别金矿含矿及无矿构造——以川西北阿西金矿和石棉田湾金矿为例 总被引:3,自引:0,他引:3
寻找构造带对于矿产勘查具有积极意义,对构造的含矿性进行判别,尤其对于野外地表露头无矿化显示及隐伏构造的含矿性更为关键。为了对构造的含矿性进行快速识别,采用X荧光测量方法、α怀测氡方法、地气测量方法等现场方法及不同方法技术的配合进行了金矿含矿与无矿构造的识别研究。川西北阿西金矿及石棉田湾金矿的试验结果表明,上述方法技术及其组合可以有效地判别金矿含矿和无矿构造。 相似文献