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1.
向阳坪铀矿床是桂北苗儿山地区最具代表性的花岗岩型铀矿床,对该矿床矿石矿物REE开展了微区原位研究并结合前人研究成果进行了综合分析,表明铀黑∑REE介于689.12×10~(-6)～869.31×10~(-6)之间,LREE相对富集,HREE相对亏损具强Eu负异常及Ce正异常,TE_(1,3)值介于1.26～1.33之间,具典型M型四分组效应;沥青铀矿∑REE介于569.73×10~(-6)～3 373.83×10~(-6)之间表现出两种特征:①LREE富集,HREE亏损,轻重稀土元素分馏程度较大具强Eu负异常和弱Ce正异常,配分曲线呈右倾型;②轻重稀土元素分馏程度较小,Eu负异常明显弱Ce负异常,配分曲线呈海鸥型。围岩稀土元素配分模式相似,Y/Ho值范围狭窄,指示具有相同物源;矿石矿物稀土元素与围岩存在较大差异,亲缘性不明显。成矿作用伴随围岩发生蚀变及围岩高铀背景;成矿流体具多阶段、富U-Y-REE特征,铀主要来自深部热液,围岩贡献不显著;矿床定位受构造-岩体联合控制,矿体规模、形态受构造规模、产状控制。 相似文献
2.
内蒙古东七一山萤石矿床的稀土元素地球化学特征及成因 总被引：8，自引：1，他引：8
运用等离子质谱和等离子体光谱对内蒙古东七一山萤石矿的萤石矿石和围岩样品的稀土元素进行了系统分析.结果表明,矿石的∑REE<30×10-6,LREE为5×10-6～15×10-6,HREE<5×10-6,Y<20 ×10-6;而围岩的∑REE>290×10-6,LREE>240×10-6,HREE>40×10-6,Y>70×10-6.可将萤石矿石的稀土元素的分布型式分为轻、重稀土富集型两类一类矿石的∑REE多小于29×10-6,LREE/HREE和La/Yb分别大于7和12,δEu、δCe的变化范围分别为0.85～1.10,Ce、Eu基本不显异常;另一类的∑REE 约18×10-6 ,LREE/HREE和La/Yb分别小于3和2,δEu为0.45～0.70,δCe为0.70～0.90,具明显的负Eu异常,Ce微具负异常.矿石与围岩的稀土地球化学研究显示,该萤石矿系岩浆热液成因. 相似文献
3.
那哥铜多金属矿床是江南古陆西南端黔东南地区多金属矿床的典型代表。该矿床产于新元古界地层中,受近东西向构造控制,与辉绿岩空间接触。利用ICP-MS,本文系统获得了该矿床矿石、赋矿围岩、外围花岗岩和隐伏花岗斑岩的REE组成,结果显示矿石具有变化的总稀土含量(∑REE=6.61×10-6～235×10-6)、轻稀土富集和负Eu异常(δEu=0.59～0.88)特征;赋矿围岩∑REE值范围较宽,介于74.2×10-6～286×10-6,并具有轻稀土富集和负Eu异常(δEu=0.79～0.88)特征;辉绿岩∑REE值介于78.1×10-6～90.9×10-6,较为稳定,为轻稀土富集和不明显的Eu异常特征(δEu介于0.98～1.01);花岗岩总稀土含量稳定(∑REE=132×10-6～193×10-6),具有轻稀土富集和明显的Eu负异常特征(δEu介于0.55～0.79);新发现隐伏花岗斑岩∑REE=74.9×10-6～120×10-6,具有轻稀土明显富集和显著的Eu负异常(δEu=0.44～0.56)。对比研究认为,那哥铜多金属矿床成矿流体中的REE主要继承围岩,表明部分成矿物质由赋矿地层岩石提供。 相似文献
4.
通过对罗平富乐铅锌矿区地层及矿石进行了稀土元素地球化学特征对比研究.结果显示,梁山组样品 ΣREE值25.91×10-6~108.40×10-6,δEu值0.35~0.73,δCe值0.64~1.35.具Eu负异常和Ce弱正异常;阳新组碳酸盐岩样品 ΣREE值0.82×10-6~6.75×10-6,δEu值0.15~0.97,δCe值0.22~0.62,具Eu负异常和Ce负异常;玄武岩样品 ΣREE值204.17×10-6~290.57×10-6,δEu值变化范围0.91~0.97,δCe值1.02~1.03,Eu异常和Ce异常不明显.峨眉山玄武岩、阳新组、梁山组岩石与矿石REE配分模式比较区别明显,暗示成矿物质并非这些地层提供另有其它来源;梁山组及含矿地层阳新组样品为轻稀土富集型,并具有Eu负异常,暗示地层可能形成于被动大陆边缘还原环境. 相似文献
5.
西昆仑阿巴列克地区地层样品稀土元素地球化学特征 总被引：1，自引：0，他引：1
阿巴列克地区位于西昆仑铅、锌、铜等多金属矿带的中部,该区具有极大的找矿潜力。为阐述成矿物质来源,本文系统测定了该区霍什拉甫组8条地层剖面82件样品的稀土元素组成。分析结果表明,样品的稀土元素含量变化较大,其∑REE、∑LREE、∑HREE、Y含量的变化范围分别为(7.52~220.70)×10-6(、5.82~198.46)×10-6、(1.49~32.74)×10-6和(4.77~91.30)×10-6;绝大多数样品的球粒陨石标准化配分模式均为典型的LREE富集型(∑LREE/∑HREE平均值6.57),轻重稀土分馏显著[(La/Yb)N平均值8.20],并具弱负Eu异常(δEu平均值0.77),Ce异常不明显(δCe平均值0.88)。对比研究发现,阿巴列克地区地层样品与西昆仑多金属矿带内其它四个代表性矿床(铁克里克、塔木、卡兰古、托库孜阿特)的岩石、矿石样品的稀土元素组成特征较一致,表明该矿带众多矿床的成矿物质与围岩二者间存在密切的成因联系。 相似文献
6.
《矿物岩石地球化学通报》2016,(5)
为研究滇西小龙河锡矿床和来利山锡矿床的成矿流体演化特征和矿床成因,采用等离子质谱法(ICP-MS)对2个矿床中的脉石矿物萤石和方解石进行了微量元素和稀土元素分析测试。结果表明,小龙河矿床萤石的稀土元素总量(ΣREE)为12.86×10-6~2275.96×10-6,具有弱的负Ce异常和强的负Eu异常,相对富集Rb、Th、U、Pr、Nd和Sm等元素。来利山矿床方解石的ΣREE值低,为3.18×10-6~29.16×10-6,具有弱的负Ce异常,相对富集Rb、Ba、Th、U、Sr和Eu等元素。2个矿床的Y/HoLa/Ho图解和Tb/Ca-Tb/La图解指示萤石和方解石均为热液成因。小龙河矿床成矿物质主要来源于岩浆热液,随着成矿流体的演化,后期明显带有沉积地层物质加入,而来利山矿床成矿物质主要来源于围岩地层。 相似文献
7.
贵州遵义牛蹄塘组黑色岩系有机质的稀土元素地球化学研究 总被引：4，自引：0，他引：4
以贵州遵义寒武纪初牛蹄塘组黑色岩系的有机质为分析对象,对22个样品的稀土元素(REE)组成进行了研究,结果表明:①有机质的∑REE占全岩∑REE的lO%左右,且其REE标准化配分曲线不同于全岩的.由于有机质主要来自海洋上层水体中的微生物,囚而可以认为其REE特征代表的是古海洋上层水体的稀土元素组成特征;②有机质的REE总量变化于11.6×10-6～548×10-6之间,Ce异常系数变化于O.40～O.92之间,Eu异常系数变化于O.59～1.14之间.有机质的ce异常系数和LaN/CeN值在剖面上显示明显的变化,指示研究区经历了大陆斜坡到大洋盆地再到大陆边缘的环境,指示在寒武纪初存在一次海侵. 相似文献
8.
藏北南羌塘陆块北缘晚三叠世弄佰组火山岩的特征及构造环境 总被引：1，自引：0，他引：1
藏北南羌塘陆块北缘发育一套晚三叠世火山岩,命名为弄佰组。该组火山岩以玄武岩为主。岩石化学成分以低TiO_2、FeO Fe_2O_3、K_2O为特征。∑REE介于162.91×10~(-6)383.4×10~(-6)之间,∑Ce／∑Y介于1.83～3.00之间,δEu介于0.47～0.97之间,平均为0.73,负Eu异常较明显。微量元素Sr、K、Rb、Ba、Th、Ce、Sm强烈富集,Ta、Nb、P、Ti、Cr相对亏损。岩石学和岩石地球化学特征表明弄佰组火山岩形成于消减带岛弧区。弄佰组火山岩出露于龙木错-双湖结合带的南侧,K-Ar同位素年龄值为223Ma±5Ma.与双湖带中蓝片岩和绿片岩相变质岩系的形成年龄(220～235Ma)基本一致,时空关系的紧密相连,说明其形成可能与晚三叠世龙木错-双湖古特提斯洋的南向俯冲消减事件有关。 相似文献
9.
浙江八面山萤石矿床稀土元素地球化学特征及成因探讨 总被引：4，自引：2，他引：2
对浙江八面山萤石矿床中不同类型萤石矿石和围岩样品的稀土元素的系统分析表明,细粒萤石矿石的ΣREE〈39×10-6,LREE为14.36×10-6～34.24×10-6,HREE0.96×10-6～2.04×10-6,Y〈3×10-6;巨晶萤石矿石中的ΣREE3.62×10-6～20.81×10-6,LREE2.71×10-6～17.67×10-6,HREE0.24×10-6～1.49×10-6;而围岩花岗岩的ΣREE460.29×10-6,LREE225.97×10-6,HREE91.32×10-6,Y＆gt;140×10-6;沉积岩中的ΣREE20.22×10-6、LREE16.11×10-6、HREE1.61×10-6。矿石与围岩中沉积岩的稀土总量、轻稀土、重稀土和Y的含量接近,与花岗岩的稀土总量、轻稀土、重稀土和Y元素含量相差悬殊。萤石矿石的稀土分布型式主要为轻稀土富集型,（La/Yb）N通常多数大于8,在8.07～17.26间,δEu值在0.45～1.30,δCe在0.89～1.14间,Ce、Eu基本不显异常。矿石与围岩的稀土地球化学研究显示,八面山萤石矿床为受地层、岩体与断裂共同控制＂三位一体＂的低温热液型矿床。 相似文献
10.
《矿物学报》2017,(5)
乐红铅锌矿床位于扬子地块西南缘,是滇东北铅锌(银)多金属矿集区中的典型代表。通过不同中段典型矿化-蚀变样品中白云石、方解石、重晶石及闪锌矿稀土元素地球化学研究,探讨了该矿床的成矿流体来源。灰黑色白云岩、脉状-团块状白云石、斑团状-脉状重晶石、脉状方解石和各世代闪锌矿的∑REE均较低,均值分别为6.44×10-6、5.62×10-6、4.66×10-6和8.88×10-6,S1:1.12×10-6,S2:0.35×10-6,S3:2.75×10-6;δEu分别为0.72、0.80、68.27和0.65,S1:2.08,S2:3.78,S3:0.75;稀土配分模式为LREE富集-HREE亏损的右倾型。白云石、方解石和闪锌矿在REE配分模式、Eu和Ce异常及La/Ho-Y/Ho图解上的分布等均与未蚀变白云岩接近,表明成矿流体主要来源于碳酸盐地层中的循环水;而早阶段重晶石稀土元素特征差别明显,可能与早期深部流体有关。综合研究表明成矿流体具多源性,可能为源自于深部流体沿构造带运移至有利部位与碳酸盐岩地层中循环水发生混合。Eu、Ce异常特征表明,从成矿早阶段到成矿晚阶段,成矿过程经历了早期高温、氧化→成矿期中高温、弱还原→晚期中低温、还原的演化过程。 相似文献
11.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
12.
Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
13.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
14.
Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
15.
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
18.
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献
20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献