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Alteration and mineralization styles of the orogenic disseminated Zhenyuan gold deposit,southeastern Tibet: Contrast with carlin gold deposit 预览
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作者 Huajian Li Qingfei Wang +3 位作者 Jun Deng Lin Yang Chaoyi Dong Huazhi Yu 《地学前缘:英文版》 CAS CSCD 2019年第5期1849-1862,共14页
Orogenic disseminated and Carlin gold deposits share much similarity in alteration and mineralization.The disseminated orogenic Zhenyuan Au deposit along the Ailaoshan shear zone,southeastern Tibet,was selected to cla... Orogenic disseminated and Carlin gold deposits share much similarity in alteration and mineralization.The disseminated orogenic Zhenyuan Au deposit along the Ailaoshan shear zone,southeastern Tibet,was selected to clarify their difference.The alteration and mineralization from the different lithologies,including meta-quartz sandstone,carbonaceous slate,meta-(ultra)mafic rock,quartz porphyry and lamprophyre were researched.According to the mineral assemblage and replacement relationship in all types of host rocks,two reactions show general control on gold deposition:(1) replacement of earlier magnetite by pyrite and carbonaceous material;(2) alteration of biotite and phlogopite phenocrysts in quartz porphyry and lamprophyre into dolomite/ankerite and sericite.Despite the lamprophyre is volumetrically minor and much less fractured than other host rocks,it contains a large portion of Au reserve,indicating that the chemically active lithology has played a more important role in gold precipitation compared to structure.LA-ICP-MS analysis shows that Au mainly occurs as invisible gold in fine-grained pyrite disseminated in the host rocks,with Au content reaching to 258.95 ppm.The diagenetic core of pyrite in meta-quartz sandstone enriched in Co,Ni,Mo,Ag and Hg is wrapped by hydrothermal pyrite enriched in Cu,As,Sb,Au,Tl,Pb and Bi.Different host rock lithology has much impact on the alteration and mineralization features.Carbonate and sericite in altered lamprophyre show they have higher Mg than those developed in other of host rocks denoting that the carbonate and sericite incorporated Mg from phlogopite phenocrysts in the primary lamprophyre during alteration.The ore fluid activated the diagenetic pyrite in meta-quartz sandstone leading the hydrothermal pyrite enriched in Cu,Mo,Ag,Sb,Te,Hg,Tl,Pb and Bi,but the hydrothermal pyrite in meta-(ultra)mafic rock is enriched in Co and Ni as the meta-(ultra)mafic rock host rock contain high content of Co and Ni.However,Au and As shear similar range in both types of host rocks i 展开更多
关键词 Zhenyuan GOLD DEPOSIT DISSEMINATED OROGENIC GOLD DEPOSIT Host-rock ALTERATION Mineralization style Carlin GOLD DEPOSIT
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Using trace elements of magnetite to constrain the origin of the Pingchuan hydrothermal low-Ti magnetite deposit in the Panxi area, SW China
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作者 Yanjun Wang Weiguang Zhu +3 位作者 Hong Zhong Zhongjie Bai Junhua Yao Chong Xu 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第3期376-390,共15页
The Pingchuan iron deposit, located in the Yanyuan region of Sichuan Province, SW China, has an ore reserve of 40 Mt with ~60 wt% Fe. Its genesis is still poorly understood. The Pingchuan iron deposit has a parageneti... The Pingchuan iron deposit, located in the Yanyuan region of Sichuan Province, SW China, has an ore reserve of 40 Mt with ~60 wt% Fe. Its genesis is still poorly understood. The Pingchuan iron deposit has a paragenetic sequence of an early Fe-oxide–Pyrite stage(Ⅰ) and a late Fe-oxide–pyrrhotite stage(Ⅱ). Stage Ⅰ magnetite grains are generally fragmented, euhedral–subhedral, largesized crystals accompanying with slightly postdated pyrite.Stage Ⅱ magnetite grains are mostly unfragmented, anhedral, relatively small-sized grains that co-exist with pyrrhotite. Combined with micro-textural features and previously-obtained geochronological data, we consider that these two stages of iron mineralization in the Pingchuan deposit correspond to the Permian ELIP magmatism and Cenozoic fault activity event. Both the Stage Ⅰ and Ⅱ magnetites are characterized with overall lower contents of trace elements(including Cr, Ti, V, and Ni) than the ELIP magmatic magnetite, which suggests a hydrothermal origin for them.‘‘Skarn-like’’ enrichment in Sn, Mn, and Zn in the Stage Ⅰ magnetite grains indicate significant material contributions from carbonate wall-rocks due to water–rock interaction in ore-forming processes. Stage Ⅱ magnetite grains contain higher Mn concentrations than Stage Ⅰ magnetite grains, which possibly implies more contribution from carbonate rocks. In multiple-element diagrams, the Stage Ⅰ magnetite shows systematic similarities to Kiruna-type magnetite rather than those from other types of deposits. Combined with geological features and previous studies on oxygen isotopes, we conclude that hydrothermal fluids have played a key role in the generation of the Pingchuan low-Ti iron deposit. 展开更多
关键词 SW China Pingchuan IRON DEPOSIT Low-Ti IRON DEPOSIT HYDROTHERMAL MAGNETITE
Geochronology and mineralogy of the Weishan carbonatite in Shandong province,eastern China 预览
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作者 Chen Wang Jianchao Liu +4 位作者 Haidong Zhang Xinzhu Zhang Deming Zhang Zhixuan Xi Zijie Wang 《地学前缘:英文版》 CAS CSCD 2019年第2期769-785,共17页
The Weishan REE deposit is located at the eastern part of North China Craton(NCC),western Shandong Province.The REE-bearing carbonatite occur as veins associated with aegirine syenite.LA-ICP-MS bastnaesite Th-Pb ages(... The Weishan REE deposit is located at the eastern part of North China Craton(NCC),western Shandong Province.The REE-bearing carbonatite occur as veins associated with aegirine syenite.LA-ICP-MS bastnaesite Th-Pb ages(129 Ma)of theWeishan carbonatite show that the carbonatite formed contemporary with the aegirine syenite.Based on the petrographic and geochemical characteristics of calcite,the REEbearing carbonatite mainly consists of Generation-1 igneous calcite(G-1 calcite)with a small amount of Generation-2 hydrothermal calcite(G-2 calcite).Furthermore,the Weishan apatite is characterized by high Sr,LREE and low Y contents,and the carbonatite is rich in Sr,Ba and LREE contents.Theδ13CV-PDB(-6.5‰to-7.9‰)andδ13OV-SMOW(8.48‰-9.67‰)values are similar to those of primary,mantlederived carbonatites.The above research supports that the carbonatite of the Weishan REE deposit is igneous carbonatite.Besides,the high Sr/Y,Th/U,Sr and Ba of the apatite indicate that the magma source of the Weishan REE deposit was enriched lithospheric mantle,which have suffered the fluid metasomatism.Taken together with the Mesozoic tectono-magmatic activities,the NWand NWWsubduction of Izanagi plate along with lithosphere delamination and thinning of the North China plate support the formation of theWeishan REE deposit.Accordingly,the mineralization model of theWeishan REE deposit was concluded:The spatial-temporal relationships coupled with rare and trace element characteristics for both carbonatite and syenite suggest that the carbonatite melt was separated from the CO2-rich silicate melt by liquid immiscibility.The G-1 calcites were crystallized from the carbonatite melt,which made the residual melt rich in rare earth elements.Due to the common origin of G-1 and G-2 calcites,the REE-rich magmatic hydrothermal was subsequently separated from the melt.After that,large numbers of rare earth minerals were produced from the magmatic hydrothermal stage. 展开更多
关键词 Weishan REE DEPOSIT CARBONATITE CALCITE APATITE DEPOSIT model
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Geochemical characteristics and genetic type of a lithium ore (mineralized) body in the central Yunnan Province, China 预览
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作者 Bai-dong Sun Jun-ping Liu +6 位作者 Xiao-hu Wang Yan Dao Gui-xiang Xu Xiao-zhuang Xue-qing Guan Wei Wang Dong-hu Song 《中国地质(英文)》 2019年第3期287-300,共14页
Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan... Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan Formation. This work described the morphology, structures, main ore types and geochemical characteristics of this ore body in detail, and discussed the ore-forming material source, occurrence state of lithium and the formation mechanism of lithium ores to clarify the prospecting marks. In the further exploration, comprehensive evaluation of the lithium resources of known bauxite ore bodies in central Yunnan Province should be strengthened, and the exploration of hidden lithium ore bodies should be intensified in order to discover more large and super-large lithium orebodies, which will fill the gap of the national demand for lithium resources, and promote the national defense construction and new energy industry development. 展开更多
关键词 Sedimentary-type lithium DEPOSIT STRATIFIED DEPOSIT GEOCHEMICAL characteristics METALLOGENIC mechanism Mineral resources exploration engineering Yunnan PROVINCE China
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地质普查找矿及矿床地质勘探分析 预览 被引量:1
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作者 赵建平 《世界有色金属》 2019年第7期67-67,69共2页
矿物资源的开发效率以及利用效率容易受到自然环境以及复杂地理结构的影响。而提升矿物资源开发效率以及利用效率的关键就是提高相关部门的地质普查找矿水平以及矿场地质勘探水平。基于此,本文重点以文山大腰店钻探施工为例,针对地质普... 矿物资源的开发效率以及利用效率容易受到自然环境以及复杂地理结构的影响。而提升矿物资源开发效率以及利用效率的关键就是提高相关部门的地质普查找矿水平以及矿场地质勘探水平。基于此,本文重点以文山大腰店钻探施工为例,针对地质普查找矿以及矿床地质勘探进行了详细的分析,旨在提升文山大腰店矿区矿产的开发与利用效率,带动祥云县经济的发展,以供参考。 展开更多
关键词 地质普查找矿 矿床 地质勘探
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共享单车租赁的法律问题研究 预览
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作者 郭辉 张文强 《保定学院学报》 2019年第1期49-53,共5页
共享单车的出现一定程度上改变了人们的出行方式,具有诸多优点。但共享单车在运营过程中也存在诸多问题,如共享单车租承双方权利义务尚未明确、共享单车租赁过程中人身损害的责任承担缺乏明确规范、共享单车资金安全监管空白、共享单车... 共享单车的出现一定程度上改变了人们的出行方式,具有诸多优点。但共享单车在运营过程中也存在诸多问题,如共享单车租承双方权利义务尚未明确、共享单车租赁过程中人身损害的责任承担缺乏明确规范、共享单车资金安全监管空白、共享单车安全欠缺有效规制、单车使用人信息安全存在泄露危险等。为维护共享单车租赁中各方权益,需明确共享单车租承双方权利义务、理清共享单车租赁过程中人身损害责任、严格共享单车资金安全保障、规范单车使用人信息安全保护等。 展开更多
关键词 共享单车 租赁 押金 监管
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Geochemistry and zircon U-Pb chronology of quartz porphyry in Yuejinshan Fe-polymetallic deposit of Heilongjiang 预览
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作者 JIN Ye CUI Bo +6 位作者 WANG Li YANG Baihui YIN Yue LI Qing WANG Shuo CHEN Xiaohang LIU Xiang 《世界地质:英文版》 2019年第2期67-77,共11页
Quartz porphyry in Yuejinshan Fe-polymetallic deposit is one of the rock masses, which formed the granite belt relating to the late Yanshanian skarn-type Fe-polymetallic deposits in the eastern Heilongjiang, and is al... Quartz porphyry in Yuejinshan Fe-polymetallic deposit is one of the rock masses, which formed the granite belt relating to the late Yanshanian skarn-type Fe-polymetallic deposits in the eastern Heilongjiang, and is also closely related to the metallogenic space of the Fe-polymetallic deposits. Quartz porphyry has the zircon U-Pb concordia age of 125.0±1.1 Ma, overall showing high Si (SiO 2=74.48%-- 75.00%), rich alkaline (Na2O+K 2O=7.93%-8.17%, K 2O/Na 2O=1.39-- 1.46), and poor Mg (MgO=0.27%-- 0.31%), with the A/CNK value being 0.95--0.99, having the characteristics of obvious enrichment of LREE and medium Eu negative anomaly (0.69-- 0.74), indicating that the rock belongs to quasi-aluminous high potassium calc-alkaline series and has the same characteristics as those of the I-type granite. The rock is also characterized by the enrichment of LILE and active incompatible elements, and depletion of HFSE such as Nb, Ta, P and Ti, with the Mg # value being 32--- 37, indicating that the rock originated from partial melting of crustal materials. It can be concluded from the above characteristics or data and from the distribution of contemporary magmatic rocks in the area, that quartz porphyry in Yuejinshan Fe-polymetallic deposit was formed in a tectonic background of the subduction of the paleo-Pacific plate in late Yanshanian. 展开更多
关键词 quartz PORPHYRY ZIRCON U-PB age GEOCHEMISTRY Yuejinshan Fe-polymetallic deposit
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粤北张屋坪锑矿点的矿床成因与找矿前景浅析 预览
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作者 黄红亮 《世界有色金属》 2019年第6期293-294,共2页
粤北地区矿产资源丰富,特别是粤北曲仁构造盆地,属南岭成矿带的核心区域,区内曾发现多个大中型金属矿床,小型矿床更是不计其数。通过分析张屋坪矿区的区域及矿区地质背景,在此基础上,对矿区的矿体特征和矿石特征进行研究,粗略分析其成... 粤北地区矿产资源丰富,特别是粤北曲仁构造盆地,属南岭成矿带的核心区域,区内曾发现多个大中型金属矿床,小型矿床更是不计其数。通过分析张屋坪矿区的区域及矿区地质背景,在此基础上,对矿区的矿体特征和矿石特征进行研究,粗略分析其成矿机理,总结深部找矿经验。张屋坪锑矿点与区内赤老顶锑矿床同属于一个成矿带,并且具有相似的成矿地质条件。根据矿床地质特征,沿矿床走向及倾向的延长方向、矿床两侧的次级断裂构造以及矿区深部,均具有十分重要的找矿意义。 展开更多
关键词 锑矿 矿床 找矿
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Relations of Uranium Enrichment and Carbonaceous Debris within the Daying Uranium Deposit, Northern Ordos Basin
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作者 Fan Zhang Yangquan Jiao +2 位作者 Liqun Wu Hui Rong Longhui Wang 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第1期142-157,共16页
Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitri... Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitrinite reflectance(VR),macerals,moisture,volatile matter,ash,total sulfur(St)and uranium concentration of CD within the sandstone were studied.The results show that VR ranges from 0.372%Ro to 0.510%Ro with an average value of 0.438%Ro,indicating that CD is in the stage of lignite.The contents of vitrinite(V),inertinite(I)and minerals range from 83.18%–99.48%,0–7.70%,and 0.34%–15.72%,respectively,with the corresponding average value of 95.51%,1.34%,and 3.15%,respectively which indicates that V is the major maceral.Moisture on air dried basis(Mad),volatile matter yield on dry,ash-free basis(Vdaf),ash yield on dried basis(Ad)and St mostly range from 7.95%–16.09%,44.70%–66.54%,4.84%–26.24% and 0.24%–1.12%,respectively,while their average values are 12.43%,53.41%,16.57% and 0.77%,respectively.It suggests that CD is of medium-high moisture,super-high volatile matter,low-medium ash and low sulfur.Uranium concentration ranges from 29 ppm to 92 ppm with an average value of 50 ppm,and uranium concentration increases with the decreased distance to CD.On the whole,Mad and Vdaf decrease with increasing burial depth,which indicates that CD experienced the burial metamorphism.However,Mad and Vdaf obviously decrease in uranium-rich areas whereas Ad and St noticeably increase.Comprehensive studies suggest that there is a certain relationship between uranium enrichment and CD.CD in the stage of lignite helps the adsorption of uranium.On one hand,radioactivity uranium enrichment makes organic matter maturation increase with a decrease in moisture and volatile matter.On the other hand,an increase in organic matter maturation,caused by radioactivity uranium enrichment,results in an increase in uranium minerals,which is instructive in the study of regional uranium mineralization and metallogenic regularity. 展开更多
关键词 CARBONACEOUS DEBRIS coal property parameters Daying URANIUM DEPOSIT ORDOS Basin
荷叶炒炭存性工艺优选
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作者 赵鑫 张丹捷 +5 位作者 杨颖 张学兰 张颖 刘迪 崔月莉 孙乐 《湖北中医药大学学报》 2019年第3期45-50,共6页
目的优选荷叶炒炭存性最佳炮制工艺。方法以制炭温度、制炭时间、转速为影响因素,以金丝桃苷、槲皮素、荷叶碱、总生物碱含量、外观形状为荷叶炭评价指标,并采用色差仪测定不同炒制程度的成品颜色,优选荷叶炒炭存性最佳炒制工艺。结果... 目的优选荷叶炒炭存性最佳炮制工艺。方法以制炭温度、制炭时间、转速为影响因素,以金丝桃苷、槲皮素、荷叶碱、总生物碱含量、外观形状为荷叶炭评价指标,并采用色差仪测定不同炒制程度的成品颜色,优选荷叶炒炭存性最佳炒制工艺。结果荷叶炭最佳炒制工艺为:制炭240℃,制炭时间7min,炒药机转速40 r/min;成品表面温度208℃,外观为不规则丝片,表面焦褐色,色差仪测定荷叶炭成品表面的L*、a*、b*平均值分别为28.22、4.67、7.94。结论优选得到的荷叶炭炮制工艺稳定可行,能够科学判定荷叶炭炮制终点。 展开更多
关键词 血荷叶炭 炒炭工艺 正交试验 存性
Ore Genesis for Stratiform Ore Bodies of the Dongfengnanshan Copper Polymetallic Deposit in the Yanbian Area, NE China:Constraints from LA-ICP-MS in situ Trace Elements and Sulfide S–Pb Isotopes 预览
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作者 LU Siyu REN Yunsheng +3 位作者 YANG Qun SUN Zhenming HAO Yujie SUN Xinhao 《地质学报:英文版》 SCIE CAS CSCD 2019年第5期1591-1606,共16页
The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform o... The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform ore bodies and veintype ones, controlled by the Early Permian strata and the Late Hercynian diorite intrusion, respectively. Due to the ambiguous genetic type of the stratiform ore bodies, there has been controversy on the relationship between them and veintype ore bodies. To determine the genetic type of stratiform ore bodies, laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) in situ trace elements and S–Pb isotope analysis have been carried on the sulfides in the stratiform ore bodies. Compared with that in skarn, Mississippi Valley-type(MVT), and epithermal deposits, sphalerite samples in the stratiform ore bodies of the Dongfengnanshan deposit are significantly enriched in Fe, Mn, and In, while depleted in Ga, Ge, and Cd, which is similar to the sphalerite in volcanic-associated massive sulfide(VMS) deposits. Co/Ni ratio of pyrrhotites in the stratiform ore bodies is similar to that in VMS-type deposits. The concentrations of Zn and Cd of chalcopyrites are similar to those of recrystallized VMS-type deposits. These characteristics also reflect the intermediate ore-forming temperature of the stratiform ore bodies in this deposit. Sulfur isotope compositions of sulfides are similar to those of VMS-type deposits, reflecting that sulfur originated from the Permian Miaoling Formation. Lead isotope compositions indicate mixed-source for lead. Moreover, the comparison of the Dongfengnanshan stratiform ore bodies with some VMStype deposits in China and abroad, on the trace elements and S–Pb isotope characteristics of the sulfides reveals that the stratiform ore bodies of the Dongfengnanshan deposit belong to the VMS-type, and have closely genetic relationship with the early Permian marine volcanic sedimentary rocks. 展开更多
关键词 LA-ICP-MS in situ trace element S-Pb isotope VMS-type STRATIFORM orebodies Dongfengnanshan copper POLYMETALLIC deposit Tianbaoshan ORE district
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植保无人机低空低容量喷雾在茶园的雾滴沉积分布及对茶小绿叶蝉的防治效果 预览 被引量:3
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作者 王明 王希 +4 位作者 何玲 史建苗 范劲松 钟玲 袁会珠 《植物保护》 CAS CSCD 北大核心 2019年第1期62-68,87共8页
为研究植保无人机低空低容量喷雾技术在实现茶园农药减量中的作用,通过在茶园喷施20%吡虫啉可湿性粉剂,比较其与传统大容量喷雾技术对茶小绿叶蝉Empoasca flavescens的防治效果。结果表明,使用3种植保无人机喷雾,安装有TEEJET110015#喷... 为研究植保无人机低空低容量喷雾技术在实现茶园农药减量中的作用,通过在茶园喷施20%吡虫啉可湿性粉剂,比较其与传统大容量喷雾技术对茶小绿叶蝉Empoasca flavescens的防治效果。结果表明,使用3种植保无人机喷雾,安装有TEEJET110015#喷头的植保无人机的雾滴沉积密度为24.1~127.4个/cm^2,平均值为75.8个/cm^2,沉积量为0.002~1.15μg/cm^2,均值0.58μg/cm^2;安装有TEEJET11001#喷头的植保无人机的雾滴沉积密度为15.0~80.4个/cm^2,平均值为47.7个/cm^2,沉积量均值为0.01~1.38μg/cm^2,均值0.70μg/cm^2;安装有 TEEJET11003#喷头的植保无人机的雾滴沉积密度为9.2~18.2个/cm^2,平均值为13.7个/cm^2;沉积量为0~1.14μg/cm^2,均值0.57μg/cm^2。农药利用率为49.3%~58.2%。使用3种传统器械喷雾,担架式动力喷雾机喷雾得到的沉积量为0.02~0.30μg/cm^2,均值0.16μg/cm^2,背负式手动喷雾器喷雾得到的沉积量为0.01~0.46μg/cm^2,均值0.23 μg/cm^2,背负式电动喷雾器喷雾得到的沉积量为0.01~0.65μg/cm^2,均值0.33μg/cm^2。农药利用率为33.7%~39.6%。结果表明,3种植保无人机喷雾的农药沉积量和利用率均高于3种传统的施药器械,但其喷雾的均匀性还有待提高。施药后4d,植保无人机低空低容量喷雾对茶小绿叶蝉防治效果为85.8%~90.4%,传统大容量喷雾对茶小绿叶蝉防治效果为91.8%~93.2%,两者差异不显著。药后10d,前者对茶小绿叶蝉防治效果为72.9%~75.6%,后者防治效果为65.8%~71.6%,说明植保无人机低空低容量喷雾对茶小绿叶蝉的防治效果优于传统大容量喷雾。研究结果表明,植保无人机低空低容量喷雾有着更长的持效期,为茶园的农药减施增效提供了可能性。 展开更多
关键词 植保无人机 雾滴密度 沉积量 农药利用率 茶小绿叶蝉 防治效果
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Geochemistry and Geochronology of the Gebunongba Iron Polymetallic Deposit in the Gangdese Belt, Tibet
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作者 Shunbao Gao Youye Zheng +2 位作者 Junsheng Jiang Kan Tian Jin Xu 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期296-308,共13页
The Gebunongba iron polymetallic deposit is a typical skarn deposit located at the westernmost end of the discovered iron polymetallic deposits in the Gangdese metallogenic belt. Major and trace elements of the monzon... The Gebunongba iron polymetallic deposit is a typical skarn deposit located at the westernmost end of the discovered iron polymetallic deposits in the Gangdese metallogenic belt. Major and trace elements of the monzonite granite related to mineralization show that these rocks are peraluminous(ACNK=1.15–1.21) and are rich in Si(76.63 wt.%–76.93 wt.% SiO2), K(K2 O/Na2 O ratio of 1.80–2.30), LREE and LILEs(Rb, Ba, Th, U, Pb), but is depleted in high field strength elements(Nb, Ta, Ti and HREE). In addition, these rocks show obviously negative Eu anomalies(δEu=0.48–0.55). The LA-ICPMS U-Pb age of zircons in monzonite granite is 59.72±0.55 Ma(MSWD=0.79), whereas the 40 Ar/39 Ar age of muscovite in iron ores is 59.22±0.61 Ma(MSWD=16.20). This indicates that the deposit formed at the syn-collision stage of Lhasa-India terrane is later than the northward subduction of the Yajiang crust. The monzonite granite has been probably derived from the partial melting of ancient lower crustal materials, which is probably resulted from the underplating of mantle-derived magmas. It is favorable for the formation of iron polymetallic deposit. Iron polymetallic mineralization is prevalent in Gangdese metallogenic belt at syn-collision stage. Therefore, syn-collision stage is an important mineralization stage for iron polymetallic deposits. The results of this study proved that iron polymetallic mineralization still took place in the western segment of Gangdese metallogenic belt and provided basis for further prospecting the deposits of the same type. 展开更多
关键词 western SEGMENT of the GANGDESE BELT iron POLYMETALLIC deposit GEOCHRONOLOGY METALLOGENIC environment
大型矿区有色金属矿找矿方向及矿床形成特点 预览
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作者 花冬蕾 《世界有色金属》 2019年第1期78-78,80共2页
为满足当代社会对有色金属资源需求的不断增加,针对大型矿区有色金属矿找矿方向及矿床形成特点分析。在分析过程中,首先针对大型矿区有色金属矿找矿方向进行分析,通过对其数据进行分析后,以其找矿方向为基础对有色金属矿床形成特点进行... 为满足当代社会对有色金属资源需求的不断增加,针对大型矿区有色金属矿找矿方向及矿床形成特点分析。在分析过程中,首先针对大型矿区有色金属矿找矿方向进行分析,通过对其数据进行分析后,以其找矿方向为基础对有色金属矿床形成特点进行总结,帮助今后大型矿床有色金属矿开采提供发展方向。 展开更多
关键词 矿区 有色金属 找矿 矿床
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共享单车可持续发展问题研究
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作者 沈蕾 卜训娜 《价格理论与实践》 北大核心 2019年第7期65-68,共4页
共享单车模式运营发展至今,其市场经历了爆发式增长后,现阶段逐渐趋于平稳。虽然在快速发展过程带来了诸多问题,有些问题时至今日仍然存在。但是,不可否认,共享单车的出现满足了城市居民"最后一公里"的出行需求,有利于碳减排... 共享单车模式运营发展至今,其市场经历了爆发式增长后,现阶段逐渐趋于平稳。虽然在快速发展过程带来了诸多问题,有些问题时至今日仍然存在。但是,不可否认,共享单车的出现满足了城市居民"最后一公里"的出行需求,有利于碳减排,并将"共享"理念深入人心,催生出了诸如共享充电宝、共享汽车等诸多概念。因此,总结共享单车行业发展进程中的经验教训,并对其未来发展方向进行研究显得尤为重要。本文对共享单车市场发展进程进行梳理,并对其发展中的经验与问题进行分析与反思,从而对共享单车市场未来发展方向的展望,并提出相应的对策建议。 展开更多
关键词 “互联网+” 共享单车 押金 市场准入
柴油机Urea-SCR系统沉积物生成临界状态模型研究 预览
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作者 李莉 吕林 +1 位作者 祝能 刘丙善 《内燃机》 2019年第3期15-20,24共7页
大量研究表明,Urea-SCR系统沉积物相关研究模型无法有效预测沉积物开始生成的临界状态,该临界状态常伴随着"莱登弗罗斯特"现象的消失。本研究基于"莱登弗罗斯特"点建立沉积物生成临界状态模型,由此仿真计算表征临... 大量研究表明,Urea-SCR系统沉积物相关研究模型无法有效预测沉积物开始生成的临界状态,该临界状态常伴随着"莱登弗罗斯特"现象的消失。本研究基于"莱登弗罗斯特"点建立沉积物生成临界状态模型,由此仿真计算表征临界状态的临界添蓝流量,并与试验测得的临界添蓝流量值对比,发现喷雾体积通量q>7×10^-4m^3s^-1m^-2时,基于致密喷雾"莱登弗罗斯特"点的临界状态模型有较好的仿真精度;喷雾体积通量q>7×10^-4m^3s^-1m^-2时,基于单液滴"莱登弗罗斯特"点的临界状态模型仿真误差大。究其原因,由于喷雾体积通量q>7×10^-4 m^3s^-1m^-2时,单液滴沉积并未引起沉积物生成,沉积液滴易被壁面快速蒸发热解,则在该体积通量范围内考虑尿素在壁面的蒸发热解,最终提高了模型的仿真精度,实现了各喷雾体积通量下临界状态的有效预测。 展开更多
关键词 柴油机Urea-SCR系统 沉积物 临界状态 “莱登弗罗斯特”点
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Genesis of the Huoshenmiao Mo deposit in the Luanchuan ore district, China: Constraints from geochronology, ?uid inclusion, and H-O-Sisotopes 预览
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作者 Sai Wang Bing Li +4 位作者 Xingkang Zhang Peng Wang Weiwei Chao Huishou Ye Yongqiang Yang 《地学前缘:英文版》 CAS CSCD 2019年第1期331-349,共19页
The Huoshenmiao deposit is Mo skarn deposit,located in the western part of the Luanchuan ore district.Mineralization process can be divided into a skarn and a quartz-sulfide episodes with six stages:prograde(Ⅰ),retro... The Huoshenmiao deposit is Mo skarn deposit,located in the western part of the Luanchuan ore district.Mineralization process can be divided into a skarn and a quartz-sulfide episodes with six stages:prograde(Ⅰ),retrograde(Ⅱ),quartz-K-feldspar(Ⅲ),quartz-molybdenite(Ⅳ),quartz-pyrite(Ⅴ),and quartzcalcite(Ⅵ).A combined study of geochronology,fluid inclusion(FI),and stable isotopes was conducted to constrain the mineralization age,source of ore materials,as well as the origin and evolution of the ore-forming fluids.Molybdenite Re-Os dating indicates that the deposit was formed in the Late Jurassic(-145 Ma).Theδ^34S values of sulfides range from 3.0‰to 7.1‰,implying that the ore materials in the deposit are magmatic in origin.Three types and six subtypes of FIs are distinguished,namely,aqueous two-phase(W1-and W2-type),daughter mineral-bearing multiphase(S1-and S2-type),and CO2-bearing three-phase(C1-and C2-type).In stagesⅠandⅡ,the W1-type FIs display homogenization temperatures(Th)from 496℃to>600℃,with salinities of 14.9-18.3 wt.%NaCl eqv.The FIs in stagesⅢ,Ⅳand early stageⅤcomposed of coeval S-,C-and W-types,respectively homogenize at similar Th,suggesting the occurrence of boiling.The W1-type FIs in late stageⅤand stageⅥ,yield Th of 102-406℃and salinities of 0-4.7 wt.%NaCl eqv.TheδDH2O andδ^18OH2O values of the ore-forming fluids in quartz-sulfide episode vary from 112‰to-76‰,and 11.0‰to 1.0‰,respectively.All these above observations reveal that the early ore-forming fluids are magmatic in origin,and characterized by high temperature and moderate to high salinity,and gradually evolve to low temperature,low salinity meteoric water.The Huoshenmiao Mo deposit is associated with the magmatism event induced by the protracted subduction of the Izanagi plate beneath the eastern China continent.The decrease in temperature,salinity and f(O2),as well as change of pH due to boiling and fluid-rock interaction,are the main factors controlling Mo deposition. 展开更多
关键词 Molybdenite Re-Os age Fluid INCLUSION H-O-S isotopes Huoshenmiao MO DEPOSIT Luanchuan ORE DISTRICT
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贵州铜仁松桃凉水井矿床地质特征 预览
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作者 刘东 龙中伏 《世界有色金属》 2019年第14期140-144,共5页
贵州铜仁松桃地区位于黔中~湘西北成矿远景带之松桃-瓮安碳硅泥岩型、磷块岩型铀成矿远景带上,大地构造位置地处扬子准地台铜仁宽缓褶皱区,具有较好的矿产找矿潜力。通过对区域成矿地质背景和矿床地质特征的分析,认为区内铀成矿受地层... 贵州铜仁松桃地区位于黔中~湘西北成矿远景带之松桃-瓮安碳硅泥岩型、磷块岩型铀成矿远景带上,大地构造位置地处扬子准地台铜仁宽缓褶皱区,具有较好的矿产找矿潜力。通过对区域成矿地质背景和矿床地质特征的分析,认为区内铀成矿受地层、岩性、构造、岩相古地理等多重因素控制,铀元素异常浓集中心及高异常带、伽马高异常带、黄铁矿化围岩蚀变、富有机质(炭质)夹层等为有利的找矿标志,并认为区域内在黑色岩系地层中富有机质(炭质)和黄铁矿的夹层部位找矿,特别是其黄铁矿化、硅化、黑色蚀变现象等蚀变叠加部位,有望实现找矿突破。 展开更多
关键词 矿床 地质特征 找矿标志
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湖北省石墨矿矿产特征及成矿规律 预览
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作者 易承生 《合肥工业大学学报:自然科学版》 CAS 北大核心 2019年第3期361-369,386共10页
湖北省石墨矿属中国Ⅲ级成矿(区)带-上扬子中东部(坳褶带)Ⅲ-77-②湘鄂西-黔中南-磷-铝土矿-硫铁矿-石墨成矿亚带,文章对湖北省石墨矿产资源已知矿床的成矿规律进行分析研究。研究结果表明:湖北省主要出产晶质石墨,矿床类型主要以区域... 湖北省石墨矿属中国Ⅲ级成矿(区)带-上扬子中东部(坳褶带)Ⅲ-77-②湘鄂西-黔中南-磷-铝土矿-硫铁矿-石墨成矿亚带,文章对湖北省石墨矿产资源已知矿床的成矿规律进行分析研究。研究结果表明:湖北省主要出产晶质石墨,矿床类型主要以区域变质型为主;湖北省石墨矿主要赋存于前寒武纪地层中,代表层位为上太古界-下元古界水月寺(岩群),中元古界红安(岩)群和震旦系陡山沱组;湖北省鳞片状晶质石墨矿主要分布在宜昌、广水和红安等地;湖北省石墨矿矿石类型有片岩型、片麻岩型、变粒岩型、混合岩型、透辉岩型及大理岩型,其中,构成工业矿床的主要为大理岩型、片岩、片麻岩型,以大理岩型质量最好;湖北省隐晶质石墨矿主要分布在枣阳、随县、十堰,但品位较低,难以加工利用。 展开更多
关键词 湖北省 石墨矿 矿床 地质 矿石 成矿规律
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基于存款角度提高银行经营利润的探索 预览
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作者 李媛 《山东纺织经济》 2019年第5期31-33,共3页
存款作为银行利润的“压舱石”,是银行各项业务开展的基础。银行存款的多少直接影响着银行的利润。目前,市场竞争激烈,如何通过有限的存款资源,提高银行经营利润需求的日益增长。文章通过分析银行发展存款业务所需的成本、测算存款给银... 存款作为银行利润的“压舱石”,是银行各项业务开展的基础。银行存款的多少直接影响着银行的利润。目前,市场竞争激烈,如何通过有限的存款资源,提高银行经营利润需求的日益增长。文章通过分析银行发展存款业务所需的成本、测算存款给银行带来的收益,总结出提高银行利润的途径。 展开更多
关键词 存款 经营利润
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