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61.
MAO Guangzhou HUA Renmin GAO Jianfeng ZHAO Kuidong LONG Guangming LU Huijuan YAO Junming 《《地质学报》英文版》2010,84(3):614-623
<正>Jinshan gold deposit is located in northeastern Jiangxi,South China,which is related to the ductile shear zone.It has a gold reserve of more than 200 tons,with 80%of gold occurring in pyrite. The LREE of gold-bearing pyrite is as higher as 171.664 ppm on average,with relatively higher light rare earth elements(LREE;159.556 ppm) and lower HREE(12.108 ppm).TheΣLREE/ΣHREE ratio is 12.612 and(La/Yb)_N is 11.765.These indicate that pyrite is rich in LREE.The(La/Sm)_N ratio is 3.758 and that of(Gd/Yb)_N is 1.695.These are obvious LREE fractionations.The rare earth element(REE) distribution patterns show obvious Eu anomaly with averageδEu values of 0.664,andδCe anomalies of 1.044.REE characteristics are similar to those of wall rocks(regional metamorphic rocks),but different from those of the Dexing granodiorite porphyry and Damaoshan biotite granite.These features indicate that the ore-forming materials in the Jinshan gold deposit derived from the wall rocks, and the ore-forming fluids derived from metamorphic water.The Co/Ni ratio(average value 0.38) of pyrite suggests that the Jinshan gold deposit formed under a medium-low temperature.It is inferred from the values of high-field strength elements,LREE,Hf/Sm,Nb/La,and Th/La of the pyrite that the ore-forming fluids of the Jinshan gold deposit derived from metamorphic water with ClF. 相似文献
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西藏冈底斯造山带几乎同时形成的两套埃达克岩为什么一套含矿一套不含矿? 总被引:4,自引:1,他引:3
野外地质调查结合锆石U-Pb年龄测定和岩石化学成分分析,发现西藏冈底斯碰撞造山带晚中新世发育两套埃达克岩.一套呈NS向岩墙产出,锫石U-Pb-LAICP-MS年龄为15.6~16.8 Ma,地球化学上以富Na2O、贫K2O、Sr/Y比值高为特点,不含矿;另一套呈岩株产出,锆石 U-Pb SHRIMP 年龄为14.0~15.3 Ma,地球化学上以富K2O、贫NaO、Sr/Y比值低为特点,伴随着大规模的斑岩型铜钼矿化.两套埃达克岩都高度富集大离子不相容元素(LILE)Rb、Ba、Th、U、K、Sr、Pb,强烈亏损高场强元素(HFSE)Nb、Ta、Ti,反映出俯冲组分对岩浆源区的明显影响,具备岛弧岩浆作用的基本特征.比较而言,含矿埃达克岩更富集Rb、Th、U、K、Pb,而不含矿埃达克岩更富集Sr;不含矿埃达克岩的高场强元素Nb、Ta、Ti亏损更加强烈,Zr、Hf相对富集.两套埃达克岩都是形成于碰撞后地壳伸展的同一地球动力学背景下,其岩石地球化学差异主要与岩浆源区有关.研究表明,含矿埃达克岩的岩浆源区较浅,位于下地壳底部,参与岩浆作用的俯冲组分以沉积物熔体为主,岩浆的氧化性较强,并且经历了更多的分异过程.不含矿埃达克岩的岩浆源区较深,位于岩石圈地幔上部,参与源区岩浆作用的俯冲组分主要是板片流体,岩浆氧化性较低,岩浆分异过程较少.两套埃达克岩含矿与不含矿的原因包含了源区物质组成和岩浆生成条件两方面的差异. 相似文献
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目的:观察关节软坚止痛片对兔膝骨关节炎(KOA)模型血清及关节液中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的影响。方法:将40只新西兰兔随机分为5组:空白组、模型组、玻璃酸钠组(对照组)及关节软坚止痛片低、高剂量组(简称为低、高剂量组),每组各8只。采用屈曲位石膏铁丝固定法建立兔KOA模型后进行药物干预。观察比较各组肉眼下股骨内外髁组织,血清及关节液中IL-6、TNF-α含量,光镜下软骨组织形态学及Mankin''s评分。结果:各组血清及关节液中IL-6、TNF-α水平及Mankin''s评分比较,模型组均高于空白组、对照组及低、高剂量组(P<0.05),对照组均高于低、高剂量组(P<0.05),低、高剂量组比较,差异无统计学意义(P>0.05)。肉眼下股骨内外髁组织观察及光镜下软骨组织形态学观察结果显示:对照组及高、低剂量组均优于模型组,高、低剂量组均优于对照组。结论:关节软坚止痛片可治疗兔膝骨关节炎,其疗效优于玻璃酸钠注射液治疗,其作用机制可能与抑制IL-6、TNF-α等炎性因子表达有关。 相似文献
67.
长三角盛夏—初秋强降水的延伸期过程预报探析 总被引:1,自引:1,他引:0
针对长三角汛期强降水过程,根据不同降水类型的特性,提出分时段建立低频模型并给出建模流程。综合分析长三角汛期强降水期的低频特性,将低频气旋及反气旋区分划分7个关键区。重点研究盛夏—初秋时段的强降水特征,在总结强降水期低频特征的基础上,借助EOF分解建立延伸期大—暴雨的预报模型:1区或2区有低频气旋维持并发展;6区、7区或5区存在低频反气旋。并且在7个关键区中1、2区的低频气旋及5、6、7区的低频反气旋为主要低频系统,起决定作用,而3区的低频系统为次要低频系统,起辅助作用。利用该模型提前30 d预报出2012年汛期最强降水过程,并分析本次过程的低频系统演变,给出动态演变模型。 相似文献
68.
A Dipole Pattern of Summer Precipitation over Mid-high Latitude Asia and Related Snow Cover Anomalies in the Preceding Spring
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A dipole pattern of summer precipitation over the mid-high latitudes of Asia, which is characterized by opposing summer precipitation variations between the Mongolian and Northeast China (MNC) region and the West Siberian Plain (WSP), is found to be clear and stable on both interdecadal and interannual scales during 1981- 2011. Spring snow cover anomalies over a small region within the WSP and the Heilongjiang River (HR) region are closely related to the variation of this dipole mode during the subsequent summer, and they can therefore be considered as forecasting factors. Our statistical results imply a potential process explaining the relationship between the spring snow anomalies and the summer rainfall dipole. Corresponding to the snow anomalies, Rossby waves propagate along a path from the WSP region, via the Mongolian Plateau, to the Stanovoy Range during summer. At the same time, Rossby-wave energy divergences and convergences along this path maintain and reinforce an anomalous cyclone and anticyclone pairing over the Asian continent, which is significantly linked to opposite summer precipitation anomalies between the MNC and WSP regions. Numerical experiments are need- ed to further confirm the above conjecture and demonstrate the detailed physical mechanisms linking the spring snow cover anomalies and summer precipitation dipole. 相似文献
69.
针对出行者对公交车辆运行信息的需求,基于GPS技术设计了一个动态显示公交车辆位置信息的监督站牌系统,并提供公交位置信息的网络查询服务,方便出行者了解公交车辆的实时运营信息,以及对公交车辆的实时监督.系统以LabVIEW为软件开发平台对数据进行分析与处理,利用ASP.NET进行Web网页开发并与数据库交互,实现公交系统的智能运营和智能服务.通过实际验证,该方案具有可行性、实用性. 相似文献
70.
An Overview of BCC Climate System Model Development and Application for Climate Change Studies
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WU Tongwen SONG Lianchun LI Weiping WANG Zaizhi ZHANG Hu XIN Xiaoge ZHANG Yanwu ZHANG Li LI Jianglong WU Fanghu LIU Yiming ZHANG Fang SHI Xueli CHU Min ZHANG Jie FANG Yongjie WANG Fang LU Yixiong LIU Xiangwen WEI Min LIU Qianxi ZHOU Wenyan DONG Min ZHAO Qigeng JI Jinjun Laurent LI ZHOU Mingyu 《Acta Meteorologica Sinica》2014,28(1):34-56
This paper reviews recent progress in the development of the Beijing Climate Center Climate System Model(BCC-CSM) and its four component models(atmosphere,land surface,ocean,and sea ice).Two recent versions are described:BCC-CSM1.1 with coarse resolution(approximately 2.8125°×2.8125°) and BCC-CSM1.1(m) with moderate resolution(approximately 1.125°×1.125°).Both versions are fully coupled climate-carbon cycle models that simulate the global terrestrial and oceanic carbon cycles and include dynamic vegetation.Both models well simulate the concentration and temporal evolution of atmospheric CO_2 during the 20th century with anthropogenic CO2 emissions prescribed.Simulations using these two versions of the BCC-CSM model have been contributed to the Coupled Model Intercomparison Project phase five(CMIP5) in support of the Intergovernmental Panel on Climate Change(IPCC) Fifth Assessment Report(AR5).These simulations are available for use by both national and international communities for investigating global climate change and for future climate projections.Simulations of the 20th century climate using BCC-CSMl.l and BCC-CSMl.l(m) are presented and validated,with particular focus on the spatial pattern and seasonal evolution of precipitation and surface air temperature on global and continental scales.Simulations of climate during the last millennium and projections of climate change during the next century are also presented and discussed.Both BCC-CSMl.l and BCC-CSMl.l(m) perform well when compared with other CMIP5 models.Preliminary analyses indicate that the higher resolution in BCC-CSM1.1(m) improves the simulation of mean climate relative to BCC-CSMl.l,particularly on regional scales. 相似文献