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Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The Prydz Bay belt in East Antarctica recorded two significant tectono-thermal events, the Grenvillian event and the Pan-African event, which are considered to be closely related to the evolution of the Rodinia and Gondwana supercontinents. However, the geological history and the tectonic nature of the two events remain controversial. [Methods] Mineralogical and petrological analyses, phase equilibria modelling and zircon geochronology are combined to investigate the spinel-cordierite granulite from the Mirror Peninsula in order to better understand the tectono-thermal history of the Prydz Bay belt. [Results] The spinel-cordierite granulite contains different stages of mineral assemblages. The major stage of mineral assemblage involves cordierite, spinel, biotite, sillimanite, K-feldspar and minor garnet and ilmenite. The later stage of mineral assemblage is indicated by the emergence of magnetite as the increasing volumes of biotite and cordierite. Minor garnet and corundum are locally preserved, implying the mineral reaction 'g+cor→sp+sill' and more garnet and corundum in the peak stage. The garnet grains consist of 70%-72% almandine, 20%-22% pyrope, -4% grossularite and -4% spessartine. The XFe (Fe2+/(Fe2++Mg2+)) of representative garnet grains ranges from 0.77 to 0.80. The spinel exhibits an XFe range from 0.80 to 0.86. Different cordierite grains have similar compositions with Al of 3.89-3.93 a.p.f.u (atoms per formula unit) and XFe of 0.32-0.36. Biotite has high TiO2 (4.13%-5.23%) and Ti (0.23-0.30 a.p.f.u). K-feldspar grains consist of 78%-85% orthoclase, 15%-23% albite and -1% anorthite. Based on the mineral compositions and phase equilibrium modelling, the pressure-temperature (P-T) conditions of the major stage of mineral assemblage are constrained to 870-910 °C and 0.64-0.69 GPa, followed by later retrogression to 810-820°C and 0.49-0.53 GPa. A peak stage with higher P-T conditions (T>910 °C, P>0.69 GPa) can be inferred based on the relict peak minerals and characteristic mineral compositions (e.g. Ti in biotite). Zircon grains commonly show core-mantle-rim structures in cathodoluminescence (CL) images. The LA-ICP-MS zircon U-Pb dating analyses reveal a wide age range from 613±7 Ma to 877±9 Ma (except a maximum of 916±11 Ma) for the cores. The zircon bright rims yield a weighted mean age of 526±8 Ma with a wide range of Th/U (0.06-1.23), mostly higher than 0.1. [Conclusion] Based on the results, a few conclusions can be drawn: (1) The spinel-cordierite granulite recorded medium-low pressure/high-ultrahigh temperature metamorphism with a clockwise P-T evolution path and high dT/dP. (2) The results of zircon geochronological analysis show that zircon cores mainly record U-Pb ages in the range of 800--600 Ma, younger than typical ages of Grenvillian events, which may reflect younger inherited zircon cores or significant isotopic resetting. (3) The age of -530 Ma of zircon rims is interpreted to represent the post-peak cooling stage of the Pan-African tectono-thermal event. [Significance] This study examined the P-T conditions and the zircon ages of the spinel-cordierite granulite in the Mirror Peninsula. In combination with previous results, the P-T-t path constructed for the spinel-cordierite granulite provides new constraints on the evolution of the Prydz Bay belt during the Pan-African period. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Geoscientica Sinica is the property of Acta Geoscientica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, the drawbacks of liquid lithium-ion batteries (LIBs) with carbon anodes and organic electrolytes have become more and more obvious. Safety accidents such as electrolyte leakage and overheating combustion occur frequently. In addition, traditional LIBs are unable to meet the demand for high energy density batteries as modern society develops. Due to many disadvantages mentioned above, there is an urgent need to develop a new type of battery that combines high energy density with high safety performance. Introducing a solid electrolyte was found to achieve this. Solid lithium-ion batteries (SSLBs) have higher energy density, wider operating temperature range, and higher safety level than traditional liquid ones. As one of the core materials of solid-state batteries, solid electrolyte is critical to battery performance. Garnet Li7La3Zr2O12 has high Li+ conductivity (1×10-4 ~1×10-3 S/cm), wide electrochemical window (9 V), and good stability with lithium anodes. Based on these advantages, LLZO stands out among many types of solid-state electrolytes. In this article, the improvements of ionic conductivity in garnet-type solid electrolyte are summarized. Firstly, the crystal structure of LLZO as well as the relationship between structure and conductivity is discussed. Then, three methods for improving lithium ions conductivity are reviewed, including doping element, improving sintering techniques, and adding additives. Finally, several remaining challenges for the future development of garnet-based solid state batteries are presented, which can be used as a reference for related research. [ABSTRACT FROM AUTHOR]

Objective The Tongshanling deposit in the western Nanling metallogenic belt of Hunan Province is a skarn Cu polymetallic deposit related to Ⅰ-type granodiorite. Recently, a thick stratiform W-Mo skarn ore body has been found in the limestone of the Qiziqiao Formation far from the granodiorite intrusion. Its geological characteristics, mineral assemblages and genetic types are different from those of the ore bodies in the contact zone of the intrusion. Methods In this study, timing and genesis of the Tongshanling stratiform are analysed, through field investigation, microscopic identification, in situ U-Pb dating of garnet, and LA-ICP-MS trace element analysis of scheelite. Results The following four stages of mineralization are identified: garnet skarn, epidote and chlorite skarn, quartz sulfide and quartz calcite. The U-Pb concordant age of garnet is (160.4±4.2) Ma (MSWD=0.79), is significantly later than that of the granodiorite (~167 Ma) and similar to that of the granite porphyry (~161 Ma). The total rare earth element (ΣREE) distribution pattern of the garnet core is light rare earth element (LREE) enrichment and heavy rare earth element (HREE) flat and is similar to the whole-rock ΣREE model of granite porphyry. The ΣREE distribution pattern of garnet rims is LREE-depleted and is different from that of garnet in contact zone skarns. Scheelite associated with epidote can be divided into three stages. ΣREE modes of the three stages are all LREE enrichment and HREE depletion, but the ΣREE content decreases significantly from the first stage (Sch1-a, 332×10-6-353×10-6) to the second stage (Sch1-b, 144×10-6-301×10-6) and the third stage (Sch1-c, 4.05×10-6-31.8×10-6). Scheelite associated with chlorite (Sch2) shows LREE enrichment and HREE depletion, and their ΣREE content is 51.2×10-6-139×10-6. W-Mo mineralization is mainly concentrated in the retrograde stage. The Sch1-b and Sch2 stages have higher oxygen fugacities are the main stage of W mineralization, while the other stages (Sch1-a and Sch1-c) with lower oxygen fugacities are the main stage of Mo mineralization. Comprehensive analysis reveals that the stratiform skarn and contact zone skarn in the Tongshanling and Weijia deposits are different metallogenic systems. The stratiform skarn may be related to the granite porphyry with a relatively high degree of fractionation. Conclusion More attention should be given to the late granite porphyry in deep within and at the edge of the Tongshanling deposit.

This is an article in the field of earth sciences. To reveal the mineral chemistry characteristics and metamorphic temperature of garnet in the Liwu Group due to core of Jianglang dome, the major, trace and rare earth elements of garnet were analyzed at different locations in this paper. The results show that the major-element composition of garnet in schist from the Jianglang dome is mainly Alm. ICP-MS (average content 85.82%) and LA-ICP-MS (average content 83.51%) is basically consistent within the error range of the Alm content obtained.The total content of rare earth elements (REE) is high, and show obvious LREE-depleted and HREE-enriched left-declined REE distribution patterns, with unobvious Eu anomalies and negative Ce anomalies, Enriched in large ionic strength elements (U, Ta, Hf)and depleted high field lithophile elements (K, Sr, Ba). In addition, the formation temperature of garnet in schist from the Jianglang dome is 512～583 ℃, and the formed metamorphic pressure is relatively low. It is a negative correlation between the metamorphic temperature and the distance to the Xinhuoshan granite. In conclusion, the Jianglang dome experienced “Barrovian-type” metamorphism of high greenschist facies.

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multiple interpretations exist regarding the tectonic evolution model of the Neoarchean North China Craton, requiring a more in-depth study of metamorphic processes. Systematic petrographic observations, mineral chemical analysis, phase equilibrium modeling, and zircon dating were conducted on the basic granulites from Qingyuan in northern Liaoning to elucidate their metamorphic evolution processes and geological significance. The selected samples of mafic granulites were divided into the garnet-bearing domain (19DJ07-GD) and garnet-free domain (19DJ07-NGD), with the garnet-bearing region displaying a banded and inhomogeneous distribution. Both domains exhibit two generations of granulite facies assemblages. In the garnet-bearing domain, the first-generation metamorphic mineral assemblage includes garnet + clinopyroxene + orthopyroxene + hornblende + biotite + plagioclase + quartz. Notably, the first-generation plagioclase (Pl1 ) exhibits a complex compositional zoning, with anorthite content (xAn ) increasing from the core to the mantle and then decreasing towards the rim. Similarly, the titanium component zoning in the first-generation amphibole (Amp1 ) follows a pattern of increasing from the core to the mantle and then decreasing towards the rim. Based on mineral assemblages and corresponding component zoning, it is inferred that the first-generation granulite facies metamorphic process followed a counterclockwise P-T path, involving a pre-peak P-T rise stage and a post-peak P-T drop stage. Phase equilibrium modeling constrains the peak conditions at 0. 8 ~ 0. 9 GPa/ 900 ~ 950 °C, indicative of high-ultrahigh-temperature ( HT-UHT) metamorphism conditions. Zircon dating results yielded a post-peak cooling age of 2498±6. 9 Ma (MSWD= 0. 39). Considering the regional "dome-and-keel" tectonics, the counterclockwise P-T path, and the metamorphic timing of supracrustal rock nearly synchronous with late-stage TTG magmatic pulses, the UHT metamorphism of the supracrustal rocks is believed to be controlled by the unique Archean vertical tectonics/ sagduction system. The second-generation metamorphic assemblage is characterized by locally formed coronas or symplectites of garnet + quartz ± clinopyroxene, representing high-pressure ( HP ) granulite facies metamorphism associated with a Paleoproterozoic orogenic event. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: With the advantage of high spatial resolution, low detection limit, and multi-element surface analysis, the mapping technique of laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) provides a new method for mineralogy research, which can display the element distribution characteristics in minerals, and constrain the evolution process of the ore-genesis fluid and ore genesis. The wall-rocks of magnetite-rich ore from the No.2 mining area of the Gongchangling iron deposit suffered obvious alteration, and the scale of magnetite-rich ore is roughly proportional to intensity of alteration. However regarding the hydrothermal nature, it is argued for metamorphic or magmatic hydrothermal fluid. The garnet widely occurs in the altered wall-rock, which is closely related to the genesis of the magnetite-rich ore. Thus, by LA-ICPMS mapping of garnet in the altered wall-rock of Gongchangling magnetite-rich ore, the element composition and distribution characteristics can be used to constrain the evolution process of hydrothermal fluid and the genesis of the magnetite-rich ore. OBJECTIVES: To study the composition and distribution characteristics of major and trace elements in garnet by LA-ICP-MS mapping, and to constrain the evolution process of the ore-forming fluid and the genesis of magnetiterich ore. METHODS: The LA-ICP-MS mapping technique was applied to garnets from the Gongchangling No.2 mining area by simultaneously using Agilent 7700X inductively coupled plasma-mass spectrometry (ICP-MS) and Analyte Excite 193nm laser ablation system at the laboratory of mineralization and dynamics in Chang’an University, with laser frequencies of 10-20Hz, laser ablation spot sizes of 20-150μm square, laser ablation speeds of 20-150μm/s and laser ablation energy of 5.9J/cm², within 4 hours. Fifty-one elements (from 7Li to 238U) were chosen for ICP-MS analysis and the dwell time of each element was 6ms. This method adopted an external standard (NIST610) as the calibration standard without an internal standard. The result was semi-quantitative and the color brightness was used to represent the elemental content. The Iolite software can be used to generate multi-elemental pictures and elemental ratio mappings, to facilitate data analysis and interpretation for geologists. RESULTS: (1) LA-ICP-MS mapping indicates that the Si, Al, Fe, La, Ce, Pr and Nd compositions of the centimeterscale garnet (Grt-1, particle size of 1.5cm×1.5cm) from the altered wall-rock are homogeneous, while the Mg, Mn, Ca, Li, Sc, V, heavy rare earth elements (HREEs) and Y retain the original compositional zonation. Most elements in the smaller garnet (Grt-2, particle size of 0.6cm×0.7cm) are mainly homogenized without zonation. (2) The two garnets from the altered wall-rock of the Gongchangling iron deposit show different elemental distribution. The centimeter-scale garnets (Grt-1) are more likely to retain the original compositional zonation when the metamorphic temperature is below 600℃. The results of LA-ICP-MS mapping of the centimeter-scale garnet (Grt-1) reveal the element correlations, to better understand the geochemical process in minerals. (3) The Mg content gradually increases and Mn content gradually decreases from the core to the rim of the garnet, indicating that the formation of the Gongchangling garnet is controlled by equilibrium growth and the formation temperature of the garnet gradually increases from the core to the rim. The Ca content of the garnet increases firstly and then decreases from the core to the rim, indicating that the pressure increases firstly and then decreases, which is consistent with the garnet formed during prograde metamorphism. The δEu anomalies of the garnet decreases firstly and then increases from the core to the rim, indicating that the oxygen fugacity of the metamorphic hydrothermal fluid decreases firstly and then increases. Since the characteristics of HREEs and Y in garnet are consistent with the characteristics of Ca, it is inferred that the distribution of the HREEs and Y is also mainly controlled by pressure. CONCLUSIONS: The centimeter-scale garnet from the Gongchangling altered wall-rock retains the original compositional zonation, and the LA-ICP-MS elemental mapping of the centimeter-scale garnet can be completed within 4 hours. The element distribution in the garnet indicates that the temperature gradually increases, the pressure increases firstly and then decreases, and the oxygen fugacity decreases firstly and then increases in the evolution process of the metamorphic hydrothermal fluid. Thus, it is inferred that the garnet in the altered wall-rock of the Gongchangling magnetite-rich ore was formed in the stage of prograde metamorphism associated with the Jiao—Liao—Ji Belt, and the magnetite-rich ore was derived from the reformation of BIF (low-grade iron ore) by metamorphic hydrothermal fluid. [ABSTRACT FROM AUTHOR]

Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Laodonggou gold deposit is a medium-sized gold deposit discovered in the eastern section of the Beishan metallogenic belt. It resulted from the superposition of multi-phase and multi-stage metallogenesis. Due to its complex deposit genesis, the deposit has five sections, of which skarn orebodies dominate Section III. Skarn minerals are mainly garnet, which can be divided into early and late phases, with early garnet having more oscillatory ring bands. We systematically studied the two types of garnet by detailed microscopic observation and electron microprobe. The core of the early garnet primarily consists of essonites, and the edge is calcium–iron to calcium–aluminum composition. Andradites dominate the late garnet. The chemical composition of garnet indicates that the early skarnization stage is under a moderately acidic and weakly oxidizing–to–weakly reducing hydrothermal environment, while the iron content increases in the later stage and the oxygen escape increases, resulting in increased alkalinity and oxidation. The garnets in Section Ⅲ, originating from hydrothermal metasomatism, belong to the andradite–essonite series. Essonites and andradites prevail in the early stage, accompanied by copper mineralization. With the late hydrothermal environmental changes, andradites increase, and pyrite mineralization and arsenopyrite mineralization increase as well, resulting in gold-rich mineralization.

Copyright of Mining & Metallurgy (10057854) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND Mircobeam Lu-Hf isotopic analysis on minerals provides an important means to understand the microscopic process of magmatic activity and metamorphic reaction and to trace provenance of sediment, which greatly promotes the development of petrogeochemistry. Many methods were provided to obtain accurate and precise microbeam Lu-Hf isotopic data, and many mineral standards for microbeam Lu-Hf isotopic analysis were developed. OBJECTIVES To review and understand the microbeam methods for Lu-Hf isotopic analysis. METHODS Systematic compilations of published data of standards and discussion on the different methods for microbeam Lu-Hf isotopic analysis. RESULTS The development history of microbeam Lu-Hf isotopic analysis in the past 30 years is reviewed, and the influence of 176Yb and 176Lu isobars, REE oxides, and Ta-rich matrices on the precision and accuracy of Hf isotope measurement is systematically evaluated as well as the different correction strategies and programs provided in previous studies. In addition, a comprehensive compilation of the different Yb and Lu isotopic compositions reported in references and the different methods of microbeam Lu-Hf isotopic analyses on various Hf-rich minerals such as zircon, baddeleyite, zirconolite, zirkelite, calzirtite, eudialyte, rutile, cassiterite, and columbite-group minerals is made. The micro-drill/micro-saw sampling Lu-Hf isotopic analysis of Lu-rich minerals has played an important role in revealing the multi-stage orogenic process and the duration of mineral growth. The advent of laser ablation inductively coupled plasma triple quadrupole mass spectrometry (LA-ICP-Q-MS/MS) has increased the spatial resolution of Lu-Hf single-spot/isochron dating analysis of Lu-rich minerals to the micrometer scale. This method relies on the collision reaction of Hf and NH3 to realize the online separation of Hf from Lu, and achieves the purpose of synchronous measurement of 176Lu/177Hf and 176Hf/177Hf ratios, which is introduced in detail. CONCLUSIONS The new generation of tandem multi-collector sector field mass spectrometer with collision/reaction cell has high stability and sensitivity, which can be used to determine online separation of Hf from REEs, produce high-precision Hf isotope measurements for high Yb/Hf or Ta-rich minerals under high spatial resolution conditions, and significantly improve the precision and accuracy of microbeam Lu-Hf isotopic analysis. This deserves extensive attention in the future.

The proven gold reserve accumulates over 91 t in the Yixingzhai Gold Deposit, and it is the largest gold deposit in Shanxi Province.3 types of ore bodies develop in the district, including quartz vein type, altered porphyry type, and altered breccia type. Altered breccia-type mineralization is hosted by 4 cryptoexplosive breccia pipes. The Tietangdong cryptoexplosive breccia pipe is the largest one, and the potential for mineralization and further exploration of which are important issues for mine enterprise. Based on detailed outdoor geological survey and lithology logging in the Tietangdong cryptoexplosive breccia pipe, this study figures out its formation process, which includes: no skarn breccia stage in the lower part (Ⅰ),felsite and massive skarn stage in the upper part (Ⅱ),calcite-specularite(-garnet) vein stage(Ⅲ),magmatic breccia stage with skarn fragments(Ⅳ),quartz porphyry dikes stage (Ⅴ) and quartz-sulfide vein stage (Ⅵ).There are genetic connections between the skarn section and the felsite in the upper Tietangdong cryptoexplosive breccia pipe. Both formed at 138-139 Ma. The breccia section where felsite occurs is an important prospecting target in the Tietangdong cryptoexplosive breccia pipe. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mircobeam Lu-Hf isotopic analysis on minerals provides an important means to understand the microscopic process of magmatic activity and metamorphic reaction and to trace provenance of sediment, which greatly promotes the development of petrogeochemistry. Many methods were provided to obtain accurate and precise microbeam Lu - Hf isotopic data, and many mineral standards for microbeam Lu - Hf isotopic analysis were developed. OBJECTIVES: To review and understand the microbeam methods for Lu-Hf isotopic analysis. METHODS: Systematic compilations of published data of standards and discussion on the different methods for microbeam Lu-Hf isotopic analysis. RESULTS: The development history of microbeam Lu-Hf isotopic analysis in the past 30 years is reviewed, and the influence of 176Yb and 176Lu isobars, REE oxides, and Ta-rich matrices on the precision and accuracy of Hf isotope measurement is systematically evaluated as well as the different correction strategies and programs provided in previous studies. In addition, a comprehensive compilation of the different Yb and Lu isotopic compositions reported in references and the different methods of microbeam Lu-Hf isotopic analyses on various Hf-rich minerals such as zircon, baddeleyite, zirconolite, zirkelite, calzirtite, eudialyte, rutile, cassiterite, and columbite-group minerals is made. The micro-drill/ micro-saw sampling Lu-Hf isotopic analysis of Lu-rich minerals has played an important role in revealing the multi-stage orogenic process and the duration of mineral growth. The advent of laser ablation inductively coupled plasma triple quadrupole mass spectrometry (LA-ICP-Q-MS/ MS) has increased the spatial resolution of Lu-Hf single-spot/ isochron dating analysis of Lu-rich minerals to the micrometer scale. This method relies on the collision reaction of Hf and NH3 to realize the online separation of Hf from Lu, and achieves the purpose of synchronous measurement of 176Lu/ 177Hf and 176Hf/ 177Hf ratios, which is introduced in detail. CONCLUSIONS: The new generation of tandem multi-collector sector field mass spectrometer with collision/ reaction cell has high stability and sensitivity, which can be used to determine online separation of Hf from REEs, produce high-precision Hf isotope measurements for high Yb/ Hf or Ta-rich minerals under high spatial resolution conditions, and significantly improve the precision and accuracy of microbeam Lu -Hf isotopic analysis. This deserves extensive attention in the future. [ABSTRACT FROM AUTHOR]

A gadolinium-scandium-aluminum garnet single crystal (Gd3Sc2Al3 O12, GSAG) co-doped with 2% Dy1+ and 1% Tb3+ (atomic number fraction) was grown by Czochralski method. The morphology of etched defect on the crystal surface of (111) plane was studied and the mechanism for the formation of the defects was discussed. Besides, the Vickers hardness and Mohs hardness of the (111) plane were also characterized and calculated. On the condition of 0. 2 kgf loading and 10 s keeping time, the Vickers hardness for the (111) plane is 1 267 kg/ mm², corresponding to the Mohs hardness of 7.3. The results have reference value for revealing the origin of defects in mixed garnet crystals and exploring the growth technics for high quality crystals. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conventional lithium-ion batteries using organic liquid electrolytes suffer from limited energy density and safety risks. To improve energy density and safety, all-solid-state lithium battery are developed using solid electrolytes. Among various inorganic solid-state electrolytes, the garnet-type Li7 La3 Zr2 O12 electrolytes have attracted a great deal of attention, owing to high ionic conductivity and the excellent stability against Li metal. In order to further improve the conductivity, the garnet-type electrolytes Ta and Ba co-doped Li7 La3 Zr2 O12 (Li7 - x + y La3 - y Bay Zr2 - x Tax O12 ) were prepared using solid-state synthesis method. The crystal structure, morphology and ionic conductivity of Li7 - x + y La3 - y Bay Zr2 - x Tax O12 (0. 4≤x≤0. 6, 0≤y ≤0. 05) electrolytes were systematically investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS), respectively. The results show that Ta5 + doping stabilizes the cubic phase. Meanwhile, Ba2 + as dopand and sintering agent can decrease the total resistance by promoting the growth of grains and ceramic densification. Notably, the Li6. 45 La2. 95 Ba0. 05 Zr1. 4 Ta0. 6 O12 sample presents a total conductivity of 1. 07 x10 -3 S·cm-1 at room temperature and an activation energy of 0. 378 eV. Ta5 + / Ba2 + co-doping strategy is conducive to the preparation of garnet-type electrolyte materials with high density and high conductivity. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Ahetala copper deposit is located in Arheqi County, Xinjiang Uygur Autonomous Region. It is located in the South Tianshan orogenic belt, northern margin of Tarim Basin. The deposit belongs to a typical skarn type deposit. OBJECTIVES: In order to determine the types of skarn minerals, as well as the metallogenic process and environment of the deposit. METHODS: Based on detailed field and indoor microscopic observations, electron probe microanalysis (EPMA) was carried out to determine the chemical composition of skarn minerals in the Ahetala copper deposit. RESULTS: The results showed that the skarn minerals were garnet, pyroxene, wollastonite, chlorite and epidote. The EPMA results showed that garnets were grossular and andradite. Pyroxene was diopside (Di77.74-95.46), chlorite was minnesotaite. The Mn/Fe value of diopside was 0.00-0.12, indicating the copper mineralization of this deposit. CONCLUSIONS: The skarn of the Ahetala copper deposit is a typical calcium skarn of metasomatic skarn. According to the mineral paragenetic association and metasomatism, the mineralization stages of the deposit can be divided into early skarn stage, late skarn stage (retrograde alteration), oxide stage and early sulfide stage. From the skarn period to the quartz-sulfide period, the metallogenic environment generally underwent changes from the high temperature, high oxygen fugacity, intermediate-acidic, weak oxidizing-weak reducing environment, to the low temperature, high sulfur fugacity, alkaline reducing environment. [ABSTRACT FROM AUTHOR]

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BACKGROUND Garnet is a common silicate mineral in metamorphic and magmatic rocks, and its isomorphism is very common. The existing data show that the color of garnet with different composition is quite different, but the relationship between the composition and color of garnet has not been systematically studied. OBJECTIVES To reveal the internal relationship and variation law of garnet composition, structure and color, and provide a basis for the summary and geological application of the mineralogical characteristics of garnet in different geological environments. METHODS Common red (G1), orange (G2), green (G3) and maroon (G4) garnet have been tested systematically by electron microprobe, inductively coupled plasma-mass spectrometry, X-ray powder crystal diffraction, Raman spectroscopy, infrared spectroscopy and ultraviolet-visible absorption spectroscopy. RESULTS The results showed that the samples of G1 and G4 contained more Fe (Fe3+:0.24%, 0.24%, Fe2+:1.01%, 0.89%). The samples of G2 contained higher Mn (2.76%), whereas the samples of G3 have higher Cr and V contents of 3453×10-6 and 1458×10-6, respectively. Isomorphic substitution greatly affected the crystal structure of garnet. The cell parameters were a=11.530nm(G1), 11.563nm(G2), 11.849nm(G3) and 11.470nm(G4). Trace and rare earth elements in garnet can be used to indicate the source and formation process. The rare earth element analysis showed that the total rare earth elements of garnet were distributed unevenly, and the ratio of LREE/HREE was less than 1, with enriched heavy rare earth elements. The Eu/Eu* ratio was less than 1, which was a negative Eu anomaly. Ce abnormalities of all samples were not obvious. G1 and G4 have Fe3+ electronic transition absorption peak at 570nm. G2 has Mn2+ electronic transition absorption peak near 460nm and 520nm, whereas G3 has Cr3+ electronic transition absorption peaks at 690nm. The Raman spectra of garnet samples showed obvious differences in peak intensity and position, which also reflected the ubiquitous existence of isomorphism in these garnets. The ultraviolet-visible absorption spectra of these garnets showed high consistency with its color and characteristic elements. The absorption peaks of Fe3+ in red and maroon samples at 570nm were related to the high content of Fe, while the characteristic absorption peaks of orange sample near 460 and 520nm belong to Mn2+, corresponding to the large amount of Mn (2.76%). A strong absorption peak was observed at 690nm in the green sample, which was caused by the transition of Cr3+ and the presence of trace element Cr (3453×10-6). The results showed that the color of garnet had a good correspondence with its composition and structure. CONCLUSIONS The color characteristics of garnet can be used as a typomorphic feature of minerals to indicate the existence of different characteristic elements. These methods can be used to study the isomorphism and color origin of garnet effectively.

Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A serious of lutetium stabilized gadolinium aluminum garnet transparent ceramics {(Gd, Lu)3 Al5 O12 ∶Tb, Eu} were prepared by co-precipitation method combining vacuum sintering process. Then the transparent ceramics with the thickness of 1 mm were polished. Crystal structure of transparent ceramic samples was characterized by X-ray diffraction and the optical property was characterized by fluorescence spectrophotometer and UV near infrared spectrophotometer. After the process of sintering ceramics at high temperature, the ceramic samples still maintain stable garnet phase. In the emission spectra obtained by UV excitation of different samples. 313 nm was selected as the excitation wavelength of transparent ceramics and the strongest emission peak can be obtained. The emission light from green light to red light can be adjusted. After 313 nm excitation, all transparent ceramic samples have a millisecond decay time of Eu3+ at 543 nm and 591 nm emission wavelengths. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Silicate, sulfate, carbonate and other minerals can identified by infrared spectral which is a non - destructive, rapid and batch method. In recent years, infrared spectral has played an important role in mineralogical research, mineral exploration and prospecting, mining and metallurgy. Altered minerals such as pyroxene, garnet, olivine and rock forming minerals such as feldspar quartz can be identified rapidly with Thermal Infrared ( 6000 - 14500nm, TIR), which means a lot for mineralogical research, mineral exploration and prospecting of skarn type copper - nickel sulfide type and quartz vein type deposits. OBJECTIVES: In this paper, the spectral characteristics of altered mineral and assemblage in Makeng iron deposit are quickly demonstrated by the infrared spectral measurement and analysis of two borehole cores in the deposit collected by the cores and samples center of natural resources. METHODS: Altered minerals and alteration zones were identified using Hylogger - 3 through infrared spectroscopy technology. RESULTS: The results show that the altered minerals in Makeng are include garnet, pyroxene, carbonate, chlorite, sericite, hornblende, epidote, montmorillonite, gypsum, etc. There are significant reflections at 9199nm, 9730nm, 10500nm and 11100nm for garnet. For pyroxene, the significant reflections mainly located at 11500nm and 12150nm. Altered minerals and assemblages distributes in bands spatially, which are strictly controlled by wall rock and hydrothermal metasomatism. In this study, garnet + pyroxene can be used as the typical mineral assemblage of skarn deposits, and the characteristics of alteration bands show the changs of the main orebody from high temperature to low temperature. CONCLUSIONS: Combined with the geological characteristics of the deposit, Makeng Iron Mine is inferred as a typical stratabound skarn deposit. [ABSTRACT FROM AUTHOR]

BACKGROUND: Garnet is a common silicate mineral in metamorphic and magmatic rocks, and its isomorphism is very common. The existing data show that the color of garnet with different composition is quite different, but the relationship between the composition and color of garnet has not been systematically studied and summarized. OBJECTIVES: In order to improve the research of garnet, a comprehensive and systematic comparative analysis of different garnet varieties was carried out. METHODS: The chemical composition test was completed by Institute of Geology, Chinese Academy of Geological Sciences; the name of the test instrument: electron probe ray microanalyzer, ICP - MS by the National Geological Testing Center; and the name of the test instrument: inductively coupled plasma mass spectrometer. The XRD test was completed in Institute of Physical and Chemical Technology, Chinese Academy of Sciences. The name of the test instrument is polycrystalline X - ray diffractometer. Raman test was completed in the Institute of Physical and Chemical Technology, Chinese Academy of Sciences. The FTIR test was completed in Institute of Physical and Chemical Technology, Chinese Academy of Sciences. The UV test was completed by Institute of Physical and Chemical Technology, Chinese Academy of Sciences. The name of the test instrument is Ultraviolet, Visible and Near Infrared Spectrophotometer. RESULTS: In the experimental part, four samples of garnet were divided into four groups : G 1 ( red), G2 (orange), G3 (green) and brown - red ( G4), one for each color. The results showed that the samples of G 1 and G4 contained more Fe elements ( Fe3 +: 0. 24%, 0. 24%, Fe2+ : 1.01 %, 0. 89%); the samples of G2 contained higher Mn elements (2. 76%); and the samples of G3 contained higher Cr and V elements (3453 x 10 -6, 1458 x 10 -6 ). Isomorphic substitution has effect greatly on the crystal structure of garnet. The cell parameters are a = 11. 530nm ( Gl), 11. 563 nm ( G2), I 1. 849nm ( G3) and 11. 4 70nm ( G4). Similarly, the Raman spectra of garnet samples show obvious differences in peak intensity and peak position, which also reflects the ubiquitous existence of isomorphism in these garnets, however the differences in infrared spectra of these minerals are not obvious. The ultraviolet - visible absorption spectra of these garnets show high consistency with its color and characteristic elements. The absorption peaks of Fe3 + in red samples at 570nm are related to the high content of Fe ( Fe3 + : 0. 24%, Fe2+ : 1.01 % ) in their compositions, while the characteristic absorption peaks of orange sample near 460 and 520nm belong to Mn2 +, corresponding to the large amount of Mn ( 2. 76%) . A strong absorption peak was observed at 690nm in the green sample, which was caused by the transition of Cr3+ and the presence of trace element Cr( 3453 x 10-6 ) . CONCLUSIONS: The color characteristics of garnet can be used as a typomorphic feature of minerals to indicate the existence of different characteristic elements. These methods can be used to study the isomorphism and color origin of garnet effectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Dulong Sn-Zn polymetallic deposit is located in the western margin of Cathaysia and is one of the largest cassiterite-sulfide deposits in China. Ore bodies mainly occur as strata-bound in skarns within Neoproterozoic Xinzhaiyan Formation, overlying Late Cretaceous granite. The skarn alteration and mineralization can be divided into five stages: garnet-pyroxene stage, actinolite-chlorite stage, magnetite-cassiterite stage, cassiterite-pyrrhotite-sphalerite stage, sphalerite-chalcopyrite stage. The skarn in Dulong deposit was chosen as research object, and the major and trace elements of garnet and pyroxene were analyzed by EPMA and LA-ICP-MS based on the identification of mineral assemblage and structure. The results show that garnets can be divided into three types and show certain generation characteristics. In the early stage（Grt Ⅰ）, garnet is andradite(And90-99Gr1-5), most of which is located in the nuclear part, and symbiosis with diopside; Grt Ⅱ belongs to andradite-grossular solid solution series(And50-80Gr20-50), it is formed late around Grt Ⅰ and symbiosis with hedenbergite; Grt Ⅲ is fine-grained grossular(And30-40Gr60-70) formed in the latest stage, and most of which is irregular. The change of mineral assemblages of garnet and pyroxene indicates that the oxidization of fluid decreases gradually. Trace element characteristics show that Grt Ⅰ displays LREE-enrichment and HREE-depletion, whereas Grt Ⅱ displays HREE-enrichment and LREE-depletion. It is suggested that REE distribution may be influenced by the crystal chemical structure of garnet and the solid solution endmember components. Contents of In and Sn in different generations of garnet are also divergent significantly. Contents of In and Sn in andradite（Grt Ⅰ） are（63.0-264.0）×10-6 with the average of 159.0×10-6, and（2 790-13 100）×10-6 with the average of 7 441×10-6, respectively. Contents of In and Sn in grossular（Grt Ⅱ） are（1.6-81.0）×10-6 with the average of 20.0×10-6, and（436-4 740）×10-6 with the average of 2 518×10-6, respectively. The positive correlation of contents of In and Sn in garnet implies the simultaneous and homologous relationship between them. There is a certain tendency of selective enrichment in the early stage of skarn formation. Thus, the systematic research of skarn mineralogy and mineral chemistry characteristics is of great significance to effectively constrain the evolution of ore-forming fluid in skarn alteration and mineralization process. [ABSTRACT FROM AUTHOR]

Dy3+, Eu3+ co-doped Y3MgAl3SiO12 phosphors were prepared by high temperature solid state reaction method. The structure and spectral characteristics of the samples were characterized by XRD and fluorescence spectrometer. The crystal sites and spectral characteristics of Dy3+,Eu3+ in Y3MgAl3SiO12 host along with energy transfer mechanism between both ions were investigated. Under the excitation of 367 nm near-ultraviolet light, the emission spectrum of Y3MgAl3SiO12:Dy3+, Eu3+ con-tained the characteristic transition of 6 F9/2 to 6 H15/2（487 nm blue emission） and 6 H13/2（592 nm yellow emission） of Dy3+ and the 5 D0 7 F2 and 5 D0 7 F4 characteristic emission of Eu3+（616 nm and 710 nm red emission）. There were energy transfers of quadrupole quadrupole interaction between Dy3+ and Eu3+ resulting from optical overlap between the PL of Dy3+ and the PLE of t Eu3+ in the range of 400～500 nm. Supposed that packaging the near-ultraviolet LED chip, the phosphor provided a strategy to realize single-substrate warm white LED illumination by adjusting the doping concentration ratio of Dy3+ and Eu3+. [ABSTRACT FROM AUTHOR]

Ｉｎ ｏｒｄｅｒ ｔｏ ｅｘｐｌｏｒｅ ｔｈｅ ｐｒｏｃｅｓｓｉｎｇ ｐｒｏｐｅｒｔｙ ｏｆ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒｓ ｏｆ ｎｉｃｋｅｌ￣ ｂａｓｅｄ ｓｉｎｇｌｅ ｃｒｙｓｔａｌ ｓｕｐｅｒａｌｌｏｙꎬ ａ ｓｉｎｇｌｅ￣ｆａｃｔｏｒｉａｌ ｐｌａｉｎ ｇｒｉｎｄｉｎｇ ｅｘｐｅｒｉｍｅｎｔ ｗａｓ ｃｏｎｄｕｃｔｅｄ ｔｏ ｉｎｖｅｓｔｉｇａｔｅ ｔｈｅ ｅｆｆｅｃｔ ｏｆ ｄｉｆｆｅｒｅｎｔ ｇｒｉｎｄｉｎｇ ｐａｒａｍｅｔｅｒｓ ａｎｄ ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎｓ ｏｎ ｔｈｅ ｔｈｉｃｋｎｅｓｓ ｏｆ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒｓ. Ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗｅｄ ｔｈａｔ ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｗｉｔｈ ｃｅｒｔａｉｎ ｔｈｉｃｋｎｅｓｓ ａｐｐｅａｒｓ ｏｎ ｔｈｅ ｇｒｉｎｄｉｎｇ ｓｕｒｆａｃｅ ａｎｄ ｓｕｂｓｕｒｆａｃｅ ｏｆ ｎｉｃｋｅｌ￣ｂａｓｅｄ ｓｉｎｇｌｅ ｃｒｙｓｔａｌ ｓｕｐｅｒａｌｌｏｙ ＤＤ５. Ｔｈｅ γ ｐｈａｓｅ ａｎｄ γ′ ｐｈａｓｅ ｉｎ ｔｈｅ ｐｌａｓｔｉｃ ｄｅｆｏｒｍａｔｉｏｎ ｌａｙｅｒ ｏｆ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ａｒｅ ｄｉｓｔｏｒｔｅｄ ｓｅｖｅｒｅｌｙꎬ ａｎｄ ｔｈｅ ｈａｒｄｎｅｓｓ ｏｆ ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｉｓ ｇｒｅａｔｅｒ ｔｈａｎ ｔｈａｔ ｏｆ ｔｈｅ ｍａｔｒｉｘ. Ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｖａｒｉｅｓ ｗｉｔｈ ｔｈｅ ｇｒｉｎｄｉｎｇ ｐａｒａｍｅｔｅｒｓ ａｎｄ ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎｓ. Ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｇｒｉｎｄｉｎｇ ｗｈｅｅｌ ｔａｎｇｅｎｔｉａｌ ｖｅｌｏｃｉｔｙꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｆｉｒｓｔ ｄｅｃｒｅａｓｅｓꎬ ａｎｄ ｔｈｅｎ ｉｎｃｒｅａｓｅｓꎻ ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｇｒｉｎｄｉｎｇ ｄｅｐｔｈꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｉｎｃｒｅａｓｅｓ ｃｏｎｔｉｎｕｏｕｓｌｙꎻ ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｗｏｒｋｐｉｅｃｅ ｆｅｅｄ ｖｅｌｏｃｉｔｙꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｆｉｒｓｔ ｉｎｃｒｅａｓｅｓꎬ ａｎｄ ｔｈｅｎ ｄｅｃｒｅａｓｅｓ. Ｗｉｔｈｉｎ ｔｈｅ ｒａｎｇｅ ｏｆ ｅｘｐｅｒｉｍｅｎｔ ｐａｒａｍｅｔｅｒｓꎬ ｔｈｅ ｍｉｎｉｍｕｍ ｑｕａｎｔｉｔｙ ｌｕｂｒｉｃａｔｉｏｎ ( ＭＱＬ ) ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎ ｃａｎ ｒｅｄｕｃｅ ｔｈｅ ｃｏｒｒｅｓｐｏｎｄｉｎｇ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓꎬ ｗｈｉｃｈ ｃａｎ ｂｅ ｒｅｄｕｃｅｄ ｂｙ ｕｐ ｔｏ ３. ５ μｍ. [ABSTRACT FROM AUTHOR]

For synthesizing Li6.5La3Zr1.5Ta0.5O12 solid electrolyte with high lithium-ionic conductivity at a relatively low temperature, another kind of solid electrolyte with lower melting point, Li3BO3, was added, and the molar ratio of Li3BO3 to Li6.5La3Zr1.5Ta0.5O12 changed from 0 to 0.9. As a result, the sintering temperature decreased to 800 °C. Meanwhile, the influence rules of Li3BO3 on the composition, structure and ionic conductivity of the composite electrolytes were detected and analyzed. The lithium ion conductivity of the electrolytes went up firstly and then decreased as the amount of Li3BO3 increased. And the sample with the molar ratio of 0.7 Li3BO3 got the highest ionic conductivity as high as 4.5 X 10-5 S/cm at room temperature, while the sample without Li3BO3 had only 5 5 X 10-6 S/cm Moreover, according to the scanning electron microscope (SEM) results, the addition of Li3BO3 could promote the grain growth and densification of Li6.5La3Zr1.5Ta0.5O12, as well as the total properties of the composite electrolyte. [ABSTRACT FROM AUTHOR]

An integrated study of mineralogy and in-situ LA-ICP-MS trace element analysis was conducted on rutiles from Yukahe ultrahigh-pressure metamorphic(UHPM)phengite eclogite and garnet amphibole albitite in the northern Qaidam Basin, NW China. The results show that rutiles from these two UHPM rocks have high Si contents, and during the metamorphic evolution of phengite eclogite, Si contents of rutile grains grown in different metamorphic stages as well as the core and rim parts of a single rutile grain change regularly with metamorphic pressure. The Si contents in prograde rutiles, which occur as inclusions in garnet, omphacite and phengite core, increase gradually from core((342-360)×10-6)to rim; the Si contents in peak rutiles, which coexist with garnet, omphacite and phengite in matrix or occur as inclusions in garnet mantle and rim, have the highest Si contents with an average value of 952×10-6 and a maximum value of 2 397×10-6; the Si contents in retrograde rutiles, which coexist symplectite with amphibole+plagioclase formed by omphacite decomposition or occur in phengite+quartz veins of eclogite, decrease gradually from core towards rim(the average Si content of symplectite is 726×10-6, and that of microveins is 674×10-6). Rutiles in garnet amphibole albitite mainly occur as inclusions in phengite, garnet, amphibole and albite, and the rutiles in different occurrences have obviously higher Si contents(1 808×10-6 on average)than those from phengite eclogite(762×10-6 on average). In which, the rutiles included in phengite have Si contents of(1 018-2 741)×10-6 with an average value of 1 924×10-6, whereas the rutiles hosted by albite have variable Si contents of(685-3 910)×10-6 with an average value of 1 761×10-6. Combined with the occurrences, metamorphic evolutions and whole rock compositons of phengite eclogite and garnet amphibole albitite as well as the previous results on Si-bearing rutiles of ultrahigh-pressure eclogites in Dabie-Sulu orogenic belt, it is proposed that Si contents of rutiles from UHPM rocks are positively correlated with metamorphic pressure, and the rutiles with high-Si content(>500×10-6)may be a fingerprint for eclogite experiencing ultrahigh-pressure metamorphism; the whole rock SiO2 and TiO2 contents affect the Si contents of rutiles under the same ultrahigh metamorphic pressure, and the Si contents of rutiles increase as whole SiO2 rises and TiO2 decreases. [ABSTRACT FROM AUTHOR]

Based on the analysis results of thin sections, cathodoluminescence of quartz and heavy mineral assemblages, combined with sedimentary structures and seismic reflection characteristics, the provenance direction, parent rocks and evolution characteristics of Upper Triassic-Middle Jurassic in the eastern Kuqa depression of Tarim Basin were studied. The results show that the provenance of Upper Triassic-Middle Jurassic in the eastern Kuqa depression of Tarim Basin is mainly from South Tianshan orogenic belt in the north, and the parent rocks are mainly magmatic and metamorphic with a few sedimentary. Among them, there is a higher content of terrigenous clastic lithic and quartz without luminescence in the sandstone of Taliqike Formation, and the heavy mineral assemblages are characterized by higher contents of zircon, leucosphenite and magnetite, and lower contents of garnet, indicating that the parent rocks may be early deposition of Upper Ordovician-Upper Triassic; the contents of magmatic rock lithic in the sandstone of Ahe Formation and Yangxia Formation increase, the heavy minerals are characterized by higher contents of garnet, and quartz mainly gives off blue-purple and tan light under the condition of cathodoluminescence, indicating that the parent rocks of Ahe Formation and Yangxia Formation mainly come from Permian and its underlied sediments; the contents of metamorphic rock lithic and quartz with tan luminescent in the sandstone of Kezilenu'er Formation and Qiakemake Formation increase obviously, and the content of garnet is extremely high, indicating that the influence of metamorphic parent rock is enhanced. The evolution of parent rocks in the provenance area of Late Triassic-Middle Jurassic has obvious regularity. The parent rocks are mainly sedimentary in Late Triassic, and the contents of magmatic parent rocks increase in Early Jurassic, and finally, it is characterized by metamorphic parent rocks in Middle Jurassic. In Late Triassic, the South Tianshan orogenic belt is greatly uplifted in the eastern Kuqa depression, as a result, a large number of metamorphic parent rocks are involved in the orogenic belt and denuded; in Early-Middle Jurassic, the tectonic activity in the middle section of South Tianshan orogenic belt is characterized by east and west sections, the sandstone in the eastern region firstly has high content of garnet in Early Jurassic, while the sandstone in the western region does not appear garnet abundance until Middle Jurassic. It shows that Hula and E'erbin mountains in the middle section of South Tianshan orogenic belt are uplifted and denuded strongly in Early Jurassic, but Halke mountain is uplifted consumingly in Middle Jurassic. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Futuyu orefield is composed of seven small-middle skarn Cu-Fe deposits and Mujicun porphyry Cu-Mo deposit in the northern Taihang Mountain within the Central area of the North China Craton. Garnet is the main mineral of the skarn deposits in the Futuyu orefield, which is closely related to the mineralization and the important mineral to study the genesis of the Futuyu orefield. Combined with a geological investigation and petrographic feature study, the composition of zoning garnet from four ore deposits by using electron microprobe analysis was analyzed. Garnets in this orefield were classified into Andradite-grossularite series, and from core to rim of the crystal, andradite and grossularite show a rhythmic style change. Total content of Andradite component (78.1%-86.2%) is much larger than that of Grossularite (12.91%-16.61%). According to the zoning structure and component feature of garnet, it was generated in the weak acid, low temperature and relatively oxidation environment. According to the changes of temperature, pH, oxygen fugacity and salinity of the ore-forming fluid, garnet was not formed in a completely closed balance environment and the fluid has characteristics of multi-phases and multi-periods, which is the prerequisite and important factor of the enrichment of metal in the skarn deposit.

The electron microprobe analysis results show that the garnets in the contact zones between granite and carbonate from Gejiu Sn polymetallic deposit of Yunnan are mainly grossularite, andradite and a few of pyrope and spessartite. From the inner to outer contact zones, the content of Fe of garnet has the decreasing trend, but the contents of Al and Mn have the obviously increasing trend, and the content of Sn has the weakly increasing trend. The trend is mainly related to the decrease of andradite in the inner side and the increase of spessartite in the outer side. The content of Sn of garnet with ring growth lines in the inner contact zone is less than 0.03%; the content of Sn of garnet with zonal structure in the outer contact zone is 0.50%-0.55%. The ring growth lines and zonal structure of garnet imply the chemical composition volatility of metallogenic fluid. It is related to the periodicity change of physical and chemical conditions in post-magmatic hydrothermal infiltration metasomatism between granite and surrounding rocks. Compared with the inner contact zone, the outer contact zone is more favorable to the enrichment and precipitation of Sn. [ABSTRACT FROM AUTHOR]

The ore-forming prospect of eclogite-type rutile in Yuqia is different from that in West Tieshiguan,located in the northern Qaidam ultrahigh-pressure(UHP) metamorphic belt.Recently,the large eclogite-type rutile ore deposit in Yuqia is found,but only titaniummineralization in West Tieshiguan is found.Based on detailed field geological and microscopic observation,the major elements were analyzed by electron probe;moreover,the in-situ trace element contents in garnet collected from the deposits were performed by LA-ICP-MS.The results show that the occurrences of Yuqia and West Tieshiguan eclogites are basically identical.Yuqia eclogite degenerates weakly with mineral idiomorphic granular,and garnets contain more inclusions.Major and trace earth elements have well-developed zoning characteristic,and the mantle and rim enrich rare earth element in garnets.Relatively,the degeneration of West Tieshiguan eclogite is strong and mineral xenomorphic-granular.Some garnets of eclogites contain less inclusions and the zoning of major element has been homogenized,rare earth elements of the core and mantle are more than the side.Combining the chronology evidences,Yuqia eclogite undergoes rapid subduction and exhumation of the dynamic process,and the rutiles barely turn into ilmenites.West Tieshiguan eclogite undergoes an evolution history with a rapid burial and slow uplift,and the rutiles nearly turn into ilmenites,which reveal the differences between the dynamics process and the occurrence state of rutile.These characters provide directions for the study area to further find eclogite-type rutile deposits in the northern Qaidam UHP metamorphic belt. [ABSTRACT FROM AUTHOR]