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1.
An attempt was made to test the validity of the signatures of rare earth elements (REE) as a tool to judge the effect of diagenesis on fossil teeth. Sample REE contents and features of fossil teeth and sediments from Jinsha Relics, Sichuan, Southwest China were analyzed. The difference in REE content between fossil teeth is significantly greater than that between sediments at the Jinsha Relics. Chondrite-normalized REE patterns showed that obvious LREE enrichment and strong Ce and HREE depletion occurred in all fossil teeth samples. Meanwhile δCe and δEu values varied more dramatically in fossil teeth than in sediments. Accordingly, low content, LREE enrichment, strong Ce depletion, the significantly positive correlation between LREE/HREE and δCe, and unchanged (La/Yb)N demonstrated that the fossil teeth from Jinsha Relics have not been contaminated by diagenesis. The REE signature might be a potential proxy to assess the effect of diagenesis on fossil teeth.  相似文献   

2.
The three kinds of soil formed by the weathering of the basalt in Yema village,Weining county of Guizhou province,the carbonate rock in Guiyang district and the phosphorite in the REE-bearing phosphate mining area in Zhijin county of Guizhou province were all rich in REE.The contents of LREE in these three soil were higher than that of HREE,which was caused by the different properties of LREE and HREE complexes.Since light REE could be easily absorbed by kaolinite grains,LREE was fully enriched in the process of desorption,migration and re-absorption,which formed a typical LREE soil.The chondrite normalized distribution models of those three types of REE-enriched soil are basically similar,which belong to the right deviation type,namely,rich in light rare earth element but short of heavy rare earth element,and showing Ce negative anomalies.Eu showed intense negative anomalies in the REE in the soil formed by the weathering of the sedimentary parent rocks(such as carbonate rock and phosphorite),while no pronounced Eu anomaly was found in the REE in the soil formed by the weathering of volcanic rocks(such as basalt).It is clear that though there were intense migration and enrichment of REE during the weathering process of rocks,no obvious differentiation of REE occurred and some features of the parent rocks were retained.That is why REE is of value in analyzing the source of materials.  相似文献   

3.
The compositions of REE in quartz and pyrite from the main stage of the Laowan gold deposit in Henan Province and that in quartz from Laowan granite were determined by inductively coupled plasma-mass-spectrometry (ICP-MS) to trace the source of ore-forming materials. Meanwhile, the REE compositions of the deposit ore, granite and metamorphic wall rock were also considered for comparative studies in detail. The range of ∑REE of quartz and pyrite from the deposit ores is 4.18×10-6~30.91×10-6, the average of ∑REE is 13.39×10-6, and the average of ∑REE of quartz in the Laowan granite is 6.68×10-6. There is no distinct difference of REE parameters between the deposit ore quartz and granite quartz. The quartz in gold deposit has the same REE particular parameters as quartzes from Laowan granite, such as δEu, δCe, (La/Yb)N and (La/Sm)N, partition degree of LREE to HREE, especially, the chondrite-normalized REE patterns, but no similarity to those from metamorphic wall rock, which shows that ore-forming hydrothermal fluid is mainly the fluid coming from the Laowan granite magma, rather than metamorphic fluid. Meanwhile, comparison studies on REE features between minerals from the deposit ores and related geological bodies in the deposit show that REE characteristics of minerals can serve as an indicator of ore-forming fluid properties and sources, while the REE characteristics of the bulk samples (such as deposit ores, granites and wall rocks) can not trace the source of the ore-forming materials exactly.  相似文献   

4.
Analysis on P2O5 and REE (rare earth elements) in basal Cambrian phosphorites from the Yangtze Region, showed that the phosphorites from Bailongtan in Yunnan Province, Zhijin, Jinsha, Xishui, Zunyi, Tianzhu and Tongren in Guizhou Province, Shangrao in Jiangxi Province, Jiangshan in Zhejiang Province and Nanjing in Jiangsu Province contained high REE contents in phosphorites, especially those from Tianzhu and Tongren in Guizhou Province, Shangrao in Jiangxi Province, Jiangshan in Zhejiang Province and Nanjing in Jiangsu Province. Among them, the highest REE contents reached up to 1361.59×10-6 and P2O5 contents up to 29.45%. In contrast, phosphorites from Kaiyang, Qingzhen and Zhenyuan in Guizhou Province had relatively low total REE contents and low P2O5 contents, with the lowest total REE content of 53.19×10-6, and the lowest P2O5 content of 0.07%. REE contents exhibited a positive correlation with phosphorous contents, indicating a close genetic relationship between REE and phosphorous element. The main reason was the difference of the sedimentary environments and the contents of phosphorous and REE in deep water mass formed in upwelling currents, at an upper slope facies (Slu) in reducing condition due to relatively closed sedimentary environment. It was very difficult for the upswelling phosphorous and REE to deposit, massive phosphorous deposits were hard to be formed. At a deep water ramp facies (DRa) in the ascending process of currents, phosphorus and REE underwent differentiation rather than sedimentation. Consequently, the contents of P2O5 sediments and REE were low. At a shallow water ramp facies (including shoals and tidal flats) (SRa), with active seawater circulation and phosphatic supplement, sunny weather, high nutrition and rapid growth of algae, were benefitial for the physical enrichment of carbonate sediments. Therefore, massive phosphorite deposits were easy to be formed with abundant REE minerals, and finally turned into high REE bearing phosphorous deposits.  相似文献   

5.
Guidong granitic complex is constituted by Luxi intrusion, Xiazhuang intrusion, Maofeng intrusion, Sundong intrusion, Aizi intrusion and Siqian intrusion, which emplaced in Indosinian and early Yanshanian Periods. These intrusions varied from each other not only in major element content, aluminium saturation index, but also in values of ΣREE, δEu, and LREE/HREE, (La/Yb)N, (La/Sm)N and (Gd/Yb)N. The Maofeng intrusion, which has the closest relationship with uranium mineralization, belongs to strong peraluminous granites. Having undergone much intense fluid-rock interaction, it is characterized by typical M-type tetrad effects and lowest values of ΣREE, δEu, LREE/HREE, (La/Yb)N, (La/Sm)N and (Gd/Yb)N ratios than other studied intrusions.  相似文献   

6.
The REE transportation in two sorts of mylonites of ductile shear zone, in Hetai gold deposit, Guangdong province was studied. The results show that there is REE compositional variation regularly in the ductile shear zone. When mica-quartz schist and migmatite are changing into mylonites or ultramylonites, i.e., along with intensifying deformation,the contents of each rare earth element and the total contents of the LREE, HREE and REE increase or decrease regularly, but the REE patterns of the rock are accordant. The isocon diagram of the tectonic rocks before and after deformation shows that the REE compositional variation of the mylonites or ultramylonites are very small, but there is a few REE moving in or out in the rock deformation. The reason of the REE compositional variation is that there are volume change and fluid flow in the rock deformation, and it leads to the LREE relative enrichment and HREE relative loss.  相似文献   

7.
This paper discussed in detail about the BEE component and the characteristics of the different kinds of attapulgite clay ores as well as basalts, weathered basalts in four localities of attapulgite clay deposits of Jiangsu and Anhui Provinces of China. It is concluded that the half-weathered basalts have not distinct REE fractionation and strong weathered basalts have HREE loss in the process of the basalts weathered to form smectite group minerals. And the latefitic montmorillonite clays that formed from the basalts weathering have a distinct Ce positive anomaly, a little MREE loss and LREE and HREE renew enrichment. That reflects the particular oxidation condition in the Earth‘‘ s surface and the adsorption of the colloid solution of the lake water in the basin of the continent in the time of the clays formed. The attapulgite clays produced by the reaction between basahs with lake water in the original place of the basin have same REE characteristics as that of the basalts and the weathered basahs. This shows that REE does not transfer heavily in the progressive chemical weathering process. The sedimentary attapulgite clays have also a similar REE component and characteristic parameters to the basalts and the weathered basalts, and have a distinct Eu negative anomaly and a big value of LREE/HREE, which shows that the sedimentary clay came from the weathered basalts, and BEE partitioning patterns characters of the clays are controlled by the residual material of the weathered basalts.  相似文献   

8.
Yunkai uplifted area is one of the important metallogenic areas in Guangdong and Guangxi Provinces, in which many gold, silver, tungsten, tin, lead, zinc, molybdenum, and iron deposits were found. Dongtian gold deposit in the middle of Yunkai uplifted area, western Guangdong Province, is chosen as an example of those deposits. Comparative studies on the chondrite - normalized REE patterns and ∑REE, LREE/HREE, δEu, δCe, NLa/Yb, and NLa/Sm of auriferous quartz veins, altered gneiss-type goM ores, Caledonian gneissic biotite granite, and Late Yanshanian granite porphyry were made. The results indicate that the source of the metallogenic materials of the auriferous quartz veins and the altered gneiss-type gold ores are the same, and both of them come from the gneissic biotite granite. Metallogenic epoch of the deposit is estimated to be Caledonian period.  相似文献   

9.
The alteration types of the large-scale Tsagaan Suvarga Cu-Mo porphyry deposit mostly comprise stockwork silicification, argillization, quartz-sericite alteration, K-silicate alteration, and propylitization. The mineralized and altered zones from hydrothermal metallogenic center to the outside successively are Cu-bearing stockwork silicification zone, Cu-beating argillized zone, Cu-Mo-bearing quartz-sericite alteration zone, Cu-Mo-bearing K-silicate alteration zone, and pro- pylitization zone. The K-silicate alteration occurred in the early phase, quartz-sericite alteration in the medium phase, and argillization and carbonatization (calcite) in the later phase. Ore-bearing-altered rocks are significantly controlled by the structure and fissure zones of different scales, and NE- and NW-trending fissure zones could probably be the migration pathways of the porphyry hydrothermal system. Results in this study indicated that the less the concentrations of REE, LREE, and HREE and the more the extensive fractionation between LREE and HREE, the closer it is to the center circulatory hydrothermal ore-forming and the more extensive silicification. The exponential relationship between the fractionation of LREE and HREE and the intensity of silicification and K-silicate alteration was found in the Cu-Mo deposit studied. The negative Eu anomaly, normal Eu, positive Eu anomaly and obviously positive Eu anomaly are coincident with the enhancement of Na2O and K2O concentrations gradually, which indicated that Eu anomaly would be significantly controlled by the alkaline metasomatism of the circulatory hydrothermal ore-forming system. Therefore, such characteristics as the positive Eu anomaly, the obvious fractionation between LREE and HREE and their related special alteration lithofacies are suggested to be metallogenic prognostic and exploration indications for Tsagaan Suvarga-style porphyry Cu-Mo deposits in Mongolia and China.  相似文献   

10.
The grey gneisses are composed of early-stage layered TTG and late-stage diapiric tonalite in-trusions.The Dabie complex,northeastern Hubei Province,may be distinguished into supracrustal sequenceand grey gneisses.Different distribution patterns of rare earth elements in the early- and late- stage gneisses,i.e.the early-stage gneisses are enriched in LREE and remarkably depleted in HREE;and late-stage isslightly enriched in LREE and unevidently depleted in HREE.Geological evidence and characteristics of el-ement ratio diagrams suggest that the TTG is mainly controlled by portional partial melting and accompa-nied with fractional crystallization.The quantitative modelling of REE pattern indicates that TTG is formedfrom amphibolite transformed from basic rocks with 25%~65% of portional partial melt while thelate-stage tonalite intrusion was also accompanied with fractional crystalization of 22% biotites.  相似文献   

11.
12.
正On September 14,the reporter learnt from the Seminar on Application of New Rare Earth High-iron Aluminum Alloy Cable Technologies for Energy Conservation and Environmental Protection held by Chongqing Electric Industry Association that a rare earth high-iron aluminum alloy cable company with  相似文献   

13.
正According to news from Beijing on October 10,the Recycling Metal Branch of China Nonferrous Metals Industry Association said that in the first three quarters of 2014,China’s total output of secondary nonferrous metals(copper,aluminum,lead,zinc)was 7.37million tonnes,recording a slight increase of  相似文献   

14.
正The recent period has witnessed heated discussion on resource tax reform as a hot spot topic in the industry.Some information sources disclosed that the resource tax reform of the nonferrous metal industry would be enforced next year in the latest,the levy method will be changed from quantity-based levy to pricebased levy.  相似文献   

15.
16.
正On October 19,the Shanxi Province Pinglu County Phase I 800,000t/a Aluminum Oxide Project of Shanxi Fusheng Aluminum Co.,Ltd,a subordinate of Hangzhou Jinjiang Group,started operation.This is the fourth Aluminum oxide project constructed and operated by Jinjiang Group.  相似文献   

17.
正When eight ministries and commissions jointly issued decrees to rectify rectification the rare earth industry,and cracked down on"illegal rare earth",enterprises inside the industry are also developing joint union and coalition to usurp resources.In the evening of October 13,Hongda Xingye published public notice,saying that it planned  相似文献   

18.
正In early May,the 300,000 t/a Low Oxidizing Copper Rod Project of Hubei Daye Nonferrous Metals Co.,Ltd("Daye Nonferrous Metals")started production.As the first copper deep processing project independently invested and constructed by Daye Nonferrous Metals,this project can fully utilize its cathode copper raw material advantage to manufacture low oxidizing copper  相似文献   

19.
正From August to September,the Chinese Entrepreneur Survey System organized and implemented"Chinese Entrepreneur Questionnaire Follow-up Survey 2014".This marked the 22nd time of national entrepreneur annual follow-up survey organized by this  相似文献   

20.
正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,  相似文献   

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