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Hornfels feature in the Jiama ore deposit, Tibet and its significance on deep prospecting

WANG DengHong,TANG JuXing,YING LiJuan,LIN Bin,DING Shuai,

岩石学报 , 2011,
Abstract: Hornfels has become one of the most important host rocks in the Jiama copper polymetallic deposit since the drilling exploration exposed it more in recent years. The molybdenum and copper resources hosted in hornfels have assessed to reach the large scale, so it will provide more resources for the mine as a new ore type besides skarn type and porphyry type ore in Jiama. However, study on hornfels in Jiama is at the very low level, especially on its significance on deep prospecting. Hornfels feature in Jiama...
Geological Characteristics and Ore-Prospecting Criteria of the Ulandler Porphyry Molybdenum Deposit in Sonid Left Banner, Inner Mongolia

TAO Ji-xiong,ZHONG Ren,ZHAO Yue-ming,ZHENG Bao-jun,

地球学报 , 2010,
Abstract: The Ulandler ore deposit is a medium-size porphyry molybdenum deposit discovered during the land survey in Inner Mongolia. The ore deposit with typical porphyritic mineralization characteristics shows two mineralization shapes exhibited respectively in the upper part and the lower part. The ore bodies in the upper part exhibit multilayered veinlike and stockwork forms and are hosted in the fractures of early intruded quartz diorite and granodiorite, with molybdenite assuming large foliated lamellae and small-scaly aggregates. The ore bodies in the lower part constitute the main ore bodies, assume thick layers of veinlets and disseminations, and are hosted in the intrusive contact zone between mineralizing parent fine-grained adamellite and early intruded quartz diorite. There exist typical porphyry hydrothermal alterations in the wall rocks such as potassic alteration (biotite), beresitization, greisenization and silicification, which are genetically related to the mineralization. Geochemical exploration re-veals that there are obvious concentration zones and centers of geochemical anomalies, characterized by extensive and high intensities of metallogenic elements Mo, Cu, W and Bi. High precision magnetic survey shows that the mineralization-related quartz diorite and pyritized granodiorite have strong magnetism, whereas the wall rocks biotite granite and altered granite have no or only weak magnetism. The induced electrical medium gradient survey shows that the mineralization-related fine-grained adamellite and altered granite have high excitation rate and low resistance, which can serve as the indicators in ore prospecting. The SHRIMP zircon U-Pb age of the mineraliza-tion-related fine-grained adamellite is 131.3 ± 1.6 Ma, and the Re-Os age of molybdenite in the ore deposit is 134.1 ± 3.3 Ma, suggesting that the ore deposit was formed in Lower Cretaceous. The geological, geochemical and geophysical ore-prospecting criteria and the mineralization age of the Ulandler molybdenum porphyry deposit are important clues to further ore prospecting work in this region.
The Genesis of Mineralized Tuff of No. I Ore Body in the Xiongcun Porphyry Copper-Gold Metallogenic Ore District, Tibet: Evidence from Geochemistry and Sr-Nd-Pb Isotopes

DING Feng,LANG Xing-hai,HU Zheng-hu,YANG Huan-huan,WANG Zi-zheng,ZHANG Li,

地球学报 , 2012,
Abstract: The Xiongcun porphyry copper-gold metallogenic ore concentration area is located in the north of the middle Gangdise orogenic belt.No.Ⅰ,Ⅱ and Ⅲ main ore bodies of Xiongcun area are hosted in ore-bearing porphyries and tuff along the contact zone.This paper mainly studied geochemistry of mineralized tuff in Xiongcun No.I ore body.The mineralized tuff is similar to volcanic rocks in island arc in such geochemical characteristics as relative enrichment of LREE and LILE,depletion of HREE and HFS,low I(Sr) values(raning from 0.704163 to 0.705369,0.704907 on average),and positive ε Nd(t) values(ranging from 3.7805~7.6286,5.904121 on average).Mineralized tuff was formed in an island arc environment and was related to northwards subduction of the Neo-Tethys Ocean which occurred before India-Asian continental collision,and its source mainly came from partial melting of the juvenile basaltic strata at the bottom of the island arc.The mineral assemblage of the source region include hornblende,plagioclase and minor garnet.Mineralized tuff,ore-bearing porphyry and metallogenesis belonged to the same volcano-magma-fluid system.The mineralized tuff provided mainly external factors for the mineralization,acted as an important ore-controlling condition and also serves as an important ore-prospecting geological condition.The locations of porphyries emplaced in tuff are key ore-prospecting areas in Xiongcun area and its peripheral areas.
Application of Audio-Magnetotelluric Method for Exploration the Concealed Ore-Bodies in Yuele Lead-Zinc Ore Feild, Daguan County, NE Yunnan Province, China  [PDF]
Tran Trong Lap, Chuandong Xue, Aiying Wei, Lv Liu, Wenyao Li, Qiquan Hu, Jingjie Li, Dafeng Luo, Shaoyong Zhu, Tiangui Zhang
Journal of Geoscience and Environment Protection (GEP) , 2014, DOI: 10.4236/gep.2014.23005

The results of recent mineral exploration in the Yuele lead-zinc mining area of Daguan County, northeastern Yunnan province, showed that there are much early Paleozoic strata under thick late Paleozoic strata in northeastern Yunnan province, where developed some hidden salt structures (SSs), often with lead-zinc polymetallic mineralization varying degrees along the tension torsional fault (belts) or fracture (joint). The ore-bodies belong to the epigenetic hydrothermal filling vein-type deposit, and the prospecting potential is great. In this area, the superficial mineralization information displayed clear, but the deep mineralization is unknown, so the exploration work is restricted. The audio-megnetotelluric (AMT) surveying is an advantageous method to characterize the size, resistivity and skin depth of the polarizable mineral deposit concealed beneath thick overburden. This paper presents the surveying results using AMT method to evaluate the concealed lead-zinc mineralization in Yuele lead-zinc ore field, Daguancounty, NE Yunnan province, China. After comparing the interpretation result of AMT surveying data with the geological data and the drilling data, it is found that there is some distinct difference in resistivity and polarizable between ore-bodies hosted strata, upper strata and gypsum strata. The results show that AMT method is helpful to identify lead-zinc mineralization under this geological condition.

Zircon SHRIMP U-Pb dating and its geological significance of Lujiacun quartz-monzonite porphyry in Shangri-la County, northwestern Yunnan Province, China

XUE ChuanDong,LUO ShaoYong,SONG YuCai,YANG ZhiMing,HAN YanWei,HUANG QinHui,LI Jing,WEI AiYing,

岩石学报 , 2010,
Abstract: Lujiacun quartz-monzonite porphyry in Shangri-la County of northwestern Yunnan Province, intruded into the Middle-Triassic low-grade metamorphic rocks including slate, argillaceous siltstone and meta-basalt, bounded on the north, southwest and east by the Yidun-Zhongdian arc belt, the Jinsha River tectonic belt, and the Yangzi block respectively. It is obvious that the granitic magma is very important for studying the basement and tectonic evolution of this area. Zircon SHRIMP U-Pb dating on two samples of the quartz-monzonite porphyry show that, the latest growth rim of zircon grains has the concordant ages of 35.6±1.4Ma (MSWD=0.36, N=4) and 36.7±0.8Ma (MSWD=1.80, N=8) respectively, and with the weighted mean age of 36.2±1.3Ma (MSWD=0.35, N=12), representing the magma emplacement and/or crystallization ages for the Lujiacun pluton. However, some of the crystal zircons contain rounded or unregular cores in shape, and it is explained that the rounded zircons were captured from the wall rocks during the upwelling of the granitic magma or detrial zircons from partial melting of the lower crust. Based on the SHRIMP dating, the inherited core zircons yield ages from 413Ma to 61.2Ma, indicates that the Lujiacun quartz-monzonite porphyry has multiple sources which was closely related with the ancient basement rocks and/or metasediments under complicated geodynamic setting. Combinating with its zircon dating results and geological occurrence characteristics, and comparing to the regional evolution sequences, it is strongly reflected that the Lujiacun quartz-monzonite porphyry and associated gold-polymetallic deposits can be the prominent represent of the eastern Xizang-Jinsha River-Red River porphyry belt, formed and emplaced during the later stage of collision between Indian and Eurasian plate, and be controlled by the evolution of Indo-Asian collisional orogen and tectonomagmatism, displayed the long-distance effects in the structural transform zone of the main collisional orogenic setting since the Palaeocene. Episodically stress relaxation during tectonically transforming from transpressional ( 65~40Ma) to transtensional ( 24~17Ma) regimes probably caused multiple magmatic intrusions, which most eventually result in the mantle upwelling caused by the large-scale lateral migration of crust-mantle transitional layer and partial melting of mid- to lower-crustal rocks within the eastern Indo-Asian continental collision zone, and the time about 36Ma is the main reheating event period of the porphyry-hydrothermal metallogenic system. These conclusions provided key constraints for understanding deeply the tectonic-magmatic-metallogenic processes of the Zhongdian-Lijiang porphyry metallogenetic belt. Consequently, there is great gold-polymetallic prospective reserves of porphyry-type deposits in this ore district and surrounding areas.
Characteristics of Primary Halos and Prognosis of Concealed Ore Bodies in the Hongshi Gold Deposit, Xinjiang

CAO Jie,QIU Bin,CHAO Hui-xi,MA Li-cheng,YANG Xing-ke,SUN Ji-dong,

地球学报 , 2010,
Abstract: Based on field investigation of the Hongshi gold deposit and summarization of its geological features, the authors made a special study of the distribution characteristics and regularity of primary halos in this ore deposit by using different calculation methods, and found that the axial zoning sequence of the primary halos in the deposit is Bi-Mo-Hg-Zn-Pb-Ag-As-Cu-Sb-Au. A comparison with axial zoning sequences of other typical gold deposits in China reveals that the axial zoning sequence of primary halos in this ore deposit is obviously characterized by reversed zoning. The zoning evaluation model and the ore body superimposition pattern for this ore deposit were also set up so as to predict concealed ore bodies in the depth.
Prospecting Model Based on Ground Hyperspectral Remote Sensing Data of Hongshan Cu-Au Ore Deposit in Xinjiang

WANG Ruijun
,LI Mingsong,WANG Bing,NIU Haiwei,SUN Yongbin,LI Cunjin

- , 2016,
Abstract: 摘要: 选择新疆红山铜金矿床,使用美国ASD公司的FieldSpec Pro FR地面波谱仪,在铜金矿区及外围地段分别对各地质体的英安岩、蚀变英安岩、花岗岩、花岗闪长岩、流纹斑岩、片理化带、矿体等开展地面波谱测试,获取各地质体的波谱曲线,综合剖析各吸收峰的波谱特征和蚀变矿物的反映特征,同时结合镜下鉴定和X射线衍射分析结果,研究和总结红山铜金矿区从矿体、矿化体、近矿围岩、外围蚀变围岩至外围正常围岩的地面高光谱蚀变矿物和蚀变矿物组合分布特征,结合矿床的地质矿产特征和地面围岩蚀变特征,形成地面高光谱蚀变矿物组合分布图,构建红山铜金矿床基于地面高光谱遥感找矿模型,为后期开展航空高光谱遥感调查、高光谱蚀变矿物信息提取和找矿预测提供地面高光谱波谱数据支持和典型矿床模型基础。
Abstract: Using FieldSpec Pro FR ground spectroscopy of American ASD Company, the authors carried out ground spectrum measurement for different geological bodies such as dacite,altered dacite,granite,granodiorite,rhyolite porphyry, schistosity belt and ore body respectively in the Hongshan Cu-Au deposit.The spectrum curves of geological bodies were achieved; and then the characteristics of absorption peak of spectrum and altered minerals were generally analyzed. According to the analysis results of microscopic identification and X-ray diffraction, this paper summarized the hyperspectral distribution characteristics of altered minerals and the mineral assemblage which are distributed in ore body, mineralized body, wall rock near ore body, altered wall rock and non-altered wall rock in the Hongshan Cu ore deposit. Based on the characteristics of mineral geology and ground wall rock alteration, the hyperspectral map of altered mineral assemblage formed and the prospecting model based on ground hyperspectral remote sensing data were constructed. The research provides hyperspectral data and typical deposit model for the further aerial survey, information extraction of altered minerals, and prediction for ore deposits
Ro ňava ore field - geophysical works
Kuchari? ?udovít,Géczy Július
Acta Montanistica Slovaca , 1998,
Abstract: The article prowides a review of geophysical works in the ore field Ro ňava conducted up to date. Magnetometric and geoelectric methods and gravimetric measurements have been used. Geophysical works were focused to the solving regional problems whose contribution to the prospecting of vein deposits is not essential.
A Study of the Ore-forming Fluid in the Lengshuikeng Ag-Pb-Zn Porphyry Deposit

ZUO Li-yan,HOU Zeng-qian,SONG Yu-cai,MENG Xiang-jin,YANG Zhu-sen,

地球学报 , 2009,
Abstract: The porphyry Ag-Pb-Zn deposits are relatively rare in the world. In China, Lengshuikeng is the only deposit of this type. Based on a study of the Lengshuikeng porphyry Ag-Pb-Zn deposit in such aspects as its fluid inclusion geochemistry and stable isotope geochemistry in combination with lithologic investigation, Raman probe (LRM) and scanning electron microscopy / energy (SEM / EDS) analysis, the authors revealed characteristics of the ore-forming fluid and the evolutionary process in this deposit. The ore-forming material sources and the ore-forming mechanism were also studied. The result shows that the ore-forming fluid and the main ore-forming element (S) were derived from the porphyry system, and atmospheric water participated to some extent in the entire ore-forming process.
Comparison on elemental and isotopic geochemistry of ore-bearing and barren porphyries from the Yulong porphyry Cu deposit, east Tibet.

JIANG YaoHui,JIANG ShaoYong,DAI BaoZhang,LING HongFei,

岩石学报 , 2006,
Abstract: Geological and geochemical comparison studies indicate that the ore-bearing and barren porphyries in the Yulong porphyry Cu deposit were derived by different degree partial melting of the vein of phlogopite-garnet clinopyroxenite in an lherzolitic lithosphere. The ore-bearing porphyry represents the earliest melt derived by partial melting of accessory phases such as apatite and carbonate and hydrous mineral of phlogopite,and thus contains high contents of volatiles such as F,Cl and water,which is preferred for Cu to be extracted and enriched.The barren porphyry is the product at relatively high degree partial melting involving clinopyroxene and garnet, and thus depleted in volatiles,which makes it to be evolved as barren one.F and C1 contents (F>1200 ppm,Cl>150 ppm for ore- bearing porphyry and F<1200 ppm,Cl<150 ppm for barren porphyry) and K_2O/Na_2O (>1.2 for ore-bearing porphyry and <1.2 for barren porphyry),Sm/Yb (>6.5 for ore-bearing porphyry and <6.5 for barren porphyry) ratios of porphyries and Fe~(3 )/Fe~(2 ) ratios (>0.7 for ore-bearing porphyry and <0.7 for barren porphyry) of biotite are the important geochemical paralneter to discriminate ore-bearing and barren porphyries.The ore-bearing porphyries share similar Sr-Nd-Pb isotopic compositions as the barren porphyries,suggesting they have similar source regions.
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