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    Volume 41,2022 Issue 3
      专题研究
    • WANG Zhen-qiang, ZHANG Zhao-wei, DING Pei-chao, FENG Jian-zhi, XUE Zhi-qiang, Lü Da-xin

      2022,41(3):491-503, DOI:

      Abstract:

      Tuomoerrite ophiolitic mélange is located in the eastern segment of the northern margin of Qaidam terrane. This paper presents a systematic geochronological and petrogeochemical study of the meta-basaltic rocks in the ophiolite mélange. The metabasalts have whole-rock SiO2 contents of 47.78%~50.01%,MgO contents of 4.52%~9.36%, TFeO contents of 8.00%~14.94%,K2O contents of 0.04%~0.80%,and Na2O contents of 1.02%~4.20%, resembling those features of tholeiitic magma. They show slightly depletion in LREE, enrichment in LILE and LREE,and depletion in HFSE,similar to the patterns of arc-related volcanic rocks. These features collectively suggest a back-arc setting for the meta-basalts. The zircon U-Pb age of these metabasalts determined by LA-ICP-MS is 480.1±1.8 Ma,suggesting that the expansion time of the back-arc basin in this area should be around 480 Ma,and the oceanic slab subduction occurred in Early Ordovician.

    • CHENG Ming, LOU Yuan-lin, TANG Yao, LIAO Jia, CHEN Shu-min, LI Yi, GUO Wei, XU Kai-hong

      2022,41(3):504-518, DOI:

      Abstract:

      The Chaiwa area of Tibet was located in the middle eastern part of the Tethys Himalayan structural belt, and a large number of nearly East-West trending mafic dykes were widely developed. These mafic dykes were of great significance for studying the geological structural evolution in this area. This paper has carried out systematic petrology, chronology, and geochemistry studies on the mafic dyke rocks in the Chaiwa area. The rock types of mafic dykes in Chaiwa area were mainly diabase and gabbro porphyrite. Zircon U-Pb geochronology revealed that the crystallization ages of mafic dykes are 146~145 Ma. The basic dykes in Chaiwa were enriched in Ti, Fe, and P elements, belonged to alkaline series and enriched in LREE, showing the feather of low SiO2(47.20%~50.54%) and high Mg# (39.78~53.79), which were relatively enriched in high field strength elements(Nb, Ta, Zr, HF, Th) and were similar to the geochemical characteristics of the OIB. These geochemical characteristics indicated that the Chaiwa mafic dykes were originated from the partial melting of the asthenosphere mantle and were formed in continental margin rift setting. Combined with the development of mafic rocks in regional volcanic province, it is considered that the mafic dykes in the Chaiwa area were the products of the Kerguelen mantle plume under the back ground of continental margin rift. Although the crystallization age of the Chaiwa dyke was earlier than the peak period of Kerguelen mantle plume activity(132 Ma), it might belong to the small-scale magmatic activity before the peak period of mantle plume.

    • PAN Rong-hao, ZHU Lei, WANG Si-jia, WANG Ji-chen, WU Jia-yi, HOU Tong

      2022,41(3):519-536, DOI:

      Abstract:

      Quantitatively determining the timescale during mantle-derived magma ascent from the source to eruption or emplacement is essential for the understanding of magmatism, however, the timescales of eruption/emplacement are still poorly constrained. Shanxi Datong Cenozoic volcanic field, north of the North China Craton, is an ideal area for the investigation. In this study, we focused on the mantle olivine xenocrysts entrained in ca. 0.2 Ma Shenquansi alkali basalt, and its timescale of residence in the host magma prior to eruption. According to mineral chemistry, cores of these mantle olivine xenocrysts have Fo values up to 97.7, which can be defined as extremely magnesian olivine. They are also characterized by the extremely low contents in Ca, Mn and Ni, suggesting they were captured from metasomatized mantle peridotite. Moreover, both of the mantle olivine xenocrysts display complex CaO profiles, attributed to complex magmatic processes in the magma plumbing system. The reaction rim widths of one olivine xenocryst vary significantly, implying it has experienced multiple crack processes when captured or dur- ing transport. The Fo values of the mantle olivine xenocrysts rims are about 70, indicating they are in diffusion equilibrium with the host magma (alkali basalt) at rims. Timescales obtained by Fe-Mg diffusion chronometry of olivine mantle xenocrysts show that they have only resided in the magma for months. For a lithospheric mantle thickness of 40~70 km, the fastest average ascent rate may exceed 500 m/d.

    • LIU Chang, YANG Zhu-sen, XU Pei-yan, ZHAO Xiao-yan, XIA Wen-jie, YANG Xiao-xu

      2022,41(3):537-554, DOI:

      Abstract:

      A large number of magmatic rocks were formed in the Gangdese belt of the Qinghai-Tibet Plateau. To better understand the petrogenesis, magma source region and evolution, we have studied the petrography, geochemistry, zircon trace elements and Hf isotope analysis of the granite porphyry and rhyolitic crystal tuff in Mamu, Gakyi, western of the Central Lhasa Terrane. The granite porphyry and rhyolitic crystal tuff in Mamu were both formed at Early Cretaceous period. They are both shoshonitic rocks, enriched in large ion lithophile elements, and light rare earth elements, and depleted in high field-strength elements(HFSE) and Eu. They have high negative εHf(t) values of -9.57~-3.43 and -8.79~-4.80, and the older Hf isotopic crustal model age tDM2 of 1 774~1 388 Ma and 1 727~1 477 Ma, respectively. The Early Cretaceous magmatic rocks originated from the remelting of ancient lower crustal materials, with the mixing of mantle material. After the magma mixing, the amphibole, feldspar and biotite were first separated and crystallized, finally formed the granite porphyry and rhyolitic crystal tuff. Combined with previous studies and this paper, we infer that the Early Cretaceous magmatism in Mamu is probably due to the southward subduction of the southward subduction of Bangong-Nujiang suture zone.

    • WANG Shuai, LI Ying-jie, KONG Xing-rui, XU Zhan, WANG Jin-fang, DONG Pei-pei, JU Wen-xin, WANG Xiao-dong

      2022,41(3):555-568, DOI:

      Abstract:

      Lying along the Solonker-Linxi collisional orogenic suture zone in Sonid Youqi of Inner Mongolia, the Chaganchulu A-type monzogranite intruded into the Early Permian Halengling SSZ type ophiolitic tectonic melange belt. Based on the systematic field geological characteristics, petrology, geochemistry, zircon U-Pb chronology, the purpose of this study is to determine the genetic type of pluton, tectonic setting, and provide evidence for the closing time of the ocean basin in the eastern part of the Paleo-Asian Ocean. LA-ICP-MS zircon U-Pb dating shows that the age of the granite is 245.9±1.3 Ma, indicating that the formation age is Middle Triassic. The granite contains more alkaline feldspars, and the dark mineral is mainly biotite, with cave structure. The granite is geochemically characterized by high SiO2 (76.75%~77.18%) and alkali (Na2O+K2O=8.19%~8.62%), but low CaO (0.40%~0.44%) and MgO (0.03%~0.05%). The granite has obvious negative Eu anomaly (Eu=0.03~0.09), relative enrichment of Rb, Th, U, K and Ga, depletion of Ba, Sr, P and Ti, as well as high 10 000 Ga/Al (2.72~3.52), TFeO/MgO (29.16~57.82), (Na2O+K2O)/CaO (15.08~21.39). The petrological, mineralogical and geochemical characteristics of the granite show the characteristics of A-type granite. According to the regional, Mesozoic A-type granites have positive correlation εNd(t) value and young Nd age suggest that the granite may be caused by partial melting of intermediate basic crust in neoaccretion under low pressure and high temperature. The zircon U-Pb age of the newly obtained Chaganchulu A-type monzogranite restricts the closing time of the eastern part of the Paleo-Asian Ocean before the Middle Triassic.

    • ZHAO Wen-tao, LIU Shao-feng, CHEN Min, XUE Chun-ji

      2022,41(3):569-591, DOI:

      Abstract:

      The Zongwulong tectonic belt is located between the northern Qaidam tectonic belt and the South Qilian tectonic belt, which is generally distributed in a NWW direction. The voluminous magmatic activity in the eastern part of the tectonic belt records the process of breakup and closure of the tectonic belt during the late Paleozoic Mesozoic, while the magmatic activity in the western part is relatively rare, so it is unclear whether the eastern and western parts of the belt have the same tectonic evolution. Based on the analysis of geochemical characteristics, detrital zircon U-Pb ages and Hf isotopic compositions of the clastic rocks of the Triassic Longwuhe Formation in the western part of the tectonic belt, it is considered that the provenance of the detrital sediments in the Longwuhe Formation was slightly weathered without sedimentary recycling characteristics, and their original rocks are mainly felsic rocks. The main provenance of clastic rocks in the Longwuhe Formation is the southern Qilian Neoproterozoic granitic gneiss and early Paleozoic continental arc granite rocks, and the clastic rocks may have been deposited in Early-Middle Triassic flexural basins. Zircon U-Pb age analysis shows that the tectonic evolution of the eastern and western segments of Zongwulong tectonic belt has different processes. Limited ocean basins developed in the eastern segment but not in the western segment, the transition zone may be located between Shengge and Luogenguole area.

    • WU Meng-qi, WU Peng, WANG Die, YANG Hang, GONG Hong-sheng

      2022,41(3):592-608, DOI:

      Abstract:

      Lamei iron deposit in Central Yunnan is located in the middle section of the Jinshajiang-Ailaoshan- Honghe alkali-rich porphyry belt in the "Sanjiang" area of Southwest China. Its mineralization type is unknown and its metallogenic mechanism and resource potential are unclear, which restricts the in-depth study of prospecting and exploration in this area. On the basis of detailed geological survey, and according to the output characteristics of the ore bodies, magnetite is divided into three types: bean-star point magnetite in syenite porphyry(Ⅰ-Mag), disseminated-agglomerate magnetite in diopside hornstone(Ⅱ-Mag) and vein-shaped and sac-like filling magnetite in interlayer fracture zone(Ⅲ-Mag). Through LA-ICP-MS in-situ micro-area composition comparison, it is found that the three types of magnetites are generally enriched in Ti, Mn, V, Mg, Zn and Ni, poor in Sn, Ga and Sc and other elements. Ⅰ-Mag→Ⅱ-Mag→Ⅲ-Mag, the content of Mg, V, Zn and the ratio of Ni/Cr gradually increase, and the content of Cr, Sn and REE gradually decrease, reflecting the evolution characteristics of the three types of magmatite from magmatic origin to hydrothermal origin. Combined with Ni/(Cr+Mn) -(Ti+V), (Al+Mn)-(Ti+V) diagrams and the ore facies characteristics of magnetite, the deposit is considered to be a contact metasomatic hydrothermal iron deposit, and its mineralization material source is closely related to alkali-rich porphyry. The formation temperature of three types of magnetite is about 300~500℃, and the oxygen fugacity of Ⅰ-Mag→Ⅱ-Mag→Ⅲ-Mag tends to decrease gradually. Geochemical characteristics, mineralization temperature, oxygen fugacity and other information indicate that the deep part of Lamei iron deposit has the metallogenic potential of a porphyry copper polymetallic deposit.

    • DOU Bao-na, WANG An-dong, DING Ning, TAO Ji-hua, WAN Jian-jun

      2022,41(3):609-627, DOI:

      Abstract:

      Anhui Province is located in the southeastern China, where magmatism is frequent, and the Yanshanian magmatism is the most developed. The exposed area of magmatic rocks is more than 13 000 km2, and rocks of different types and origins are all developed, and they are concentrated in the Dabie Mountains, the middle and lower reaches of the Yangtze River, and southern Anhui. In this study, we collected 159 samples from different magmatic rock belts in Anhui Province and carried out rock density and radioactive heat-generating element content determinations. Combined with the previous test results of radioactive heat-generating elements of magmatic rocks in Anhui Province, we have carried out a systematic study on radioactive heat-generating elements of magmatic rocks in Anhui Province for the first time. The results suggest that the average contents of U, Th, and K of magmatic rocks in Anhui Province is quite different. Granitic rocks and intermediate-acid volcanic rocks have higher U, Th, and K contents, and basic magmatic rocks have relatively lower U, Th, and K contents. The radioactive heat generation rate of different types of magmatic rocks is quite different. The heat generation rates of granitic rocks and intermediate-acid volcanic rocks are relatively higher and the variation range is wide, while basic magmatic rocks are relatively lower and the variation range is narrow. The heat generation rates of some granites in Jinzhai and the middle and lower reaches of the Yangtze River exceed 5 μW/m3, which are high heat production granites. The main thermal contribution of magmatic rocks comes from the radioactive decay heat of U and Th, while that of K is relatively lower, generally no more than 10%. Through this study, combined with previous research results on geology and geothermal in Anhui Province, it is found that the radioactive heat generation of magmatic rocks is of great significance to the distribution of hot springs, dry hot rock exploration and U deposits exploration in Anhui Province, which can provide further support for the subsequent exploration and development of geothermal resources in Anhui Province.

    • SHAN Xiao-yu, WEI Liang-min, REN Guo-shun, CHEN Jia-de, LIU Ai-xin, XIE Yu-ling

      2022,41(3):628-642, DOI:

      Abstract:

      The Southern Da Hinggan Mountains is one of the most important metallogenic belt, where varied types of mineral deposits have been reported over the past few decades. The Hongling(Haobugao) Pb-Zn polymetallic ore deposit is situated in the northeast of Huanggang-Ganzhuermiao polymetallic metallogenic belt, which is located in the southern segment of the Da Hinggan Mountains, Inner Mongolia. The ore genesis and ore controls of the deposit has been widely reported, but the detailed geological work, especially the lithology of the wall rock, and the spatial distribution of mineralization and alteration in the mining area is still weak. Based on the field observation, petrographic and SEM/EDS results of the ore and altered wall rocks, this paper proposed that the Permian of the area comprise of marble and meta-volcanic or volcaniclastic rocks which has been referred to as meta-sedimentary clastic rocks. The discovery of pressure shadow with chalcopyrite and sphalerite aggregate as the core mineral imply a primary copper and zinc mineralization of Permian. Except the dominant skarn mineralization, we also confirmed some other mineralization types in the mining area, including breccia type, hydrothermal veins and carbonate replacement type. Varied types of mineralization provide new idea for the ore prospecting in the area.

    • XIU Qun-ye, YAN Yan, LIU Zheng-rong, CUI Jian-yong

      2022,41(3):643-650, DOI:

      Abstract:

      Stromatolites of Tungussia cf. nodosa Semikhatov and Baikalia lacera semikhatov were discovered for the first time in the Langyashan Formation of the original Jixian System near Shuiquanzigou, Qimantag area, Ruoqiang County, Xinjiang. The stromatolites are mostly nodular and columnar, and their overall morphological characteristics can be compared with the characteristics of Tungussia cf. and Baicalia stromatolites distributed in Neoproterozoic strata in Huaishan, Anhui and Eastern Liaoning, and some stromatolites in Jiawengmen area of East Kunlun, which is equivalent to stromatolite assemblage IV in North China. Through our work, Sm-Nd whole-rock isotopic isochron age of 815±26 Ma from the host rock of stromatolites is obtained. According to the Sm-Nd isochron age, the main characteristics of stromatolites in study area and other areas, the geological time of Langyashan Formation in Qimantag area should belong to the Neoproterozoic Qingbaikouan Period. Their host rock should expose in passive margin of a Precambrian micro-continent block disintegrated from Tarim Craton(?), which was probably assigned to Rodinian Super-Continent. The discovery of the stromatolites and dating results of the host rock provide new evidence for the tectonic evolution and diagenetic environment in western segment of the East Kunlun Mountains.

    • JING Yun-tao, LIU Yan, ZHANG Yong, Maituohuti Abuduwayiti

      2022,41(3):651-667, DOI:

      Abstract:

      Nephrite has a long history of mining and use in China, and occupies an important position in China's jade culture. According to the occurrence, the genetic types of marble-related nephrite can be divided into contact metasomatism type (skarn-type/magmatic hydrothermal type), regional metamorphism and metamorphic hydrothermal type, in which contact metasomatidm type is the most important and the main genetic type of high-quality nephrite. According to the age of the surrounding rock, the age of the ore belt formed by zircon or mica dating in nephrite and the regional geographical location, Chinese marble-related nephrite can be divided into six ore belts: Xinjiang (the upper limit of the formation age is 450~350 Ma) of the West Kunlun ore belt, Golmud of Qinghai Pro- vince (the formation age is 300~240 Ma) of the East Kunlun ore belt, Northeast China (hematite about 250~150 Ma, Laoyu about 1 700 Ma), Southwest China, Central South(volcanic rock about 682 ±62 Ma, diabase about 260 Ma) and East China. This paper mainly summarizes the geological occurrence, mineral composition, main and trace element characteristics of the whole rock, ore-forming fluid composition, zircon/mica age, spatial distribution and metallogenic regularity of nephrite deposit from the six ore belts in China. The main mineral composition of nephrite is tremolite. The ore-forming fluid composition of contact metasomatism type nephrite deposit is mainly composed of magmatic water, meteoric water and CO2 derived from decarbonation of the surrounding dolomite marble in different proportions. The ore-forming materials of Mg and Ca come from dolomite marble, while Si and H2O come from magmatic hydrothermal fluids (such as Hetan ore belt in Xinjiang). The formation of nephrite mainly experienced contact metamorphism and metamorphic metasomatism stage, prograde metamorphism stage and retrograde metamorphism stage. The metasomatism process was dolomite marble→diopside skarn or epidote skarn→tremolite skarn (coarse-grained tremolite) and coarse-grained tremolite → fine-grained tremolite. Tremolite was mainly formed in prograde metamorphism stage. The mineralization of regional metamorphic nephrite is closely related to regional metamorphism rather than magmatic activity, the ore-forming fluid is mainly meteoric water (such as Chunchuan, South Korea). The ore forming fluid of metamorphic hydrothermal nephrite is mainly metamorphic water, and the ore-forming materials Mg and Ca come from marble, Si and H2O may come from the siliceous hydrothermal solution formed by regional metamorphism and mixed magmatism(such as Xiuyan in Liaoning Province). Nephrite mainly occurs in the areas with strong tectonic activity and sections with strong contact alteration zone between intrusive rocks and carbonate rocks. The primary marble-related nephrite deposit can be explored according to mineralization mark, tectonic mark, wall rock alteration mark, secondary deposit mark, ancient mines mark, etc.

    • 方法与应用
    • ZHU Xiao-long

      2022,41(3):668-672, DOI:

      Abstract:

      The content of nickel oxide in neodymium oxide was determined by ICP-OES method. The content of nickel oxide was 0.002 7%. Various influencing factors in the detection process were analyzed. The reliability of the measurement results was expressed by relative expansion uncertainty (Urel=12%, k=2). The calculation of re-lative uncertainty component shows that the relative uncertainty component introduced by standard curve fitting is the largest, urel(c2)=5.639%, followed by the relative uncertainty component introduced by the preparation of standard solution, urel(c1)=0.879%. This paper can provide a reference of the result uncertainty analysis for relevant testing personnel.

    • 环境矿物学
    • CHEN Liang-xi, ZHOU Chuan-ye, LU An-huai, JI Xiang, DING Hong-rui, WANG Chang-qiu, LI Yan

      2022,41(3):673-680, DOI:

      Abstract:

      Natural pyrite has strong treatment capacity for Cr(Ⅵ). In this study, a natural lead-bearing pyrite sample from Shiyan, Hubei Province was selected to treat the Cr(Ⅵ)-containing wastewater. The structure and composition of the sample were analyzed by X-ray diffraction and X-ray fluorescence spectroscopy, and the influencing factors of Cr(Ⅵ) removal reaction were investigated. The results show that the natural lead-bearing pyrite sample has a good ability to remove Cr(Ⅵ), and the removal rate of Cr(Ⅵ) wastewater with a concentration of 50 mg/L is 95%~99%. The effects of pyrite particle size, reaction time and pH value on the treatment of Cr(Ⅵ)-containing wastewater were systematically studied. It was found that Cr(Ⅵ) was mainly adsorbed on the surface of pyrite particles to form flocculent substances. The results of SEM and XRD analysis of the products after the reaction showed that the flocculent substances was needle crocoite containing chromium and lead elements, which had further research significance for the use of secondary mineral precipitation as a new method for chromium removal.

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    Volume 41,2022 Issue 3
      专题研究
    • ZHANG Li-cheng, WANG Yi-tian, CHEN Xue-feng, MA Shi-qing, WANG Zhi-hua, YU Chang-fa

      2013,32(4):431-449, DOI:

      Abstract:

      The Hongyuntan iron deposit is hosted in pyroclastic rocks of the Lower Carboniferous Yamansu Formation. The ore bodies occur as layers, stratoid bodies or lenses. The principal ore mineral is magnetite, together with minor maghemite, specularite, pyrite and trace chalcopyrite. The gangue minerals include garnet, diopside, actinolite, chlorite, tremolite, epidote, biotite, albite and quartz. The ore structures are mainly of massive and disseminated forms, with occasional banded or veined forms. The ore textures are of subhedral-anhedral granular and metasomatic types. The wall rock alteration shows symmetrical zoning, and the alteration colors change from dark to light from ore bodies outwards. On the basis of observed mineral assemblages and ore fabrics, two periods of ore deposition were recognized, i.e., skarn period and hydrothermal ore-forming period, which could be further subdivided into four metallogenic stages, namely skarn stage, retrograde alteration stage (main ore-forming stage), early hydrothermal stage and quartz-sulfide stage. Electron microprobe analyses show that the end member of garnet is mainly andradite-grossularite. The composition of pyroxene is mainly diopside-asteroite. The amphiboles is composed mainly of actinolite and tremolite with minor magnesiohornblende. The composition of these skarn minerals suggests that skarn in the Hongyuntan iron deposit is calcic skarn, belonging to metasomatic skarn. The characteristics of main and trace elements suggest that the formation of magnetite was closely related to the skarn. In combination with geological characteristics, the authors suggest that the skarn might have resulted from interaction between Ca-rich pyroclastic and Fe-rich magmatic hydrothermal fluid which was transported along the fault system. The formation of magnetite was hence related to the regressive metamorphism of the skarn.

    • Gan Guoliang Yichang Institute of Geology, Mineral Resources, Chinese Academy of Geological Sciences Department of Grologicol, Atmospheric Sciences, lows State Univeraity, Ames, IAS0011, U.S.A

      1993,12(2):144-181, DOI:

      Abstract:

      This paper presents partition coefficients of 69 chemical elements (Li, Rb,Cs, K, Na, Ca, Ba, Sr, Mn, Fe, Mg, Cu, Pb, Zn, Co, Ni, Be, La, Ce, Nd,Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, Sc, Cr, In, Ga, Al, B,Cd, Sb, Bi, U, Th, Zr, Hf, Si, Ti, Ge, Sn, Mo, Nb, Ta, W, V, P, F, Cl,S, N, O, C, As, Pu, Re, Os, He, Ne, Ar, Kr and Xe) and the univalent radical (OH) in 28 minerals (olivine, clinopyroxene, orthopyroxene, amphibole,biotite, Phlogopite, plagiocla-se, K--feldspar, quartz, magnetite, ilmenite, garnet,zircon, apatite, allanite, topaz, sphene, cordierite, hauyne, leucite, nepheline,whit-lockite, brookite, petovskite, melilite, armalcolite, spinel and rutile) from 8 types of rocks, namely metaluminous (ultra) basic rock, peralkaline (ultra) basic rock, metaluminous intermediate rock, peralkaline intermediate rock,metaluminous acid rock, peralkaline acid rock, peraluminous acid rock and ultra-acid rock. It is found through an integrated ahalysis and comparison that the composition and structure of minnerals and melts seem to be the most important factors controlling mineral-melt element partitioning. Importanceshould be attached to minral structure and Al-supersaturation of melt which have, not been discussed by research workers. Finally, the present state and theproblems to be solved in the study of mineral--melt element partition coefficients are analysed, and the future trends of this research field are predibted.

    • 综合资料
    • SHEN Qi-han

      2009,28(5):495-500, DOI:

      Abstract:

      This paper has mainly recommended a mineral abbreviation list (see Table 2 and Table 3). Table 2, which contains 243 minerals, was compiled by IUGS Subcommittee on the Systematic of Metamorphic Rocks (SCMR) in 2007. The author selected other 29 minerals and, on such a basis, formulated Table 3. Thus, the total mineral abbreviations come to 272. It is hoped that they can be popularized in future and become more and more perfect through utilization, so as to provide a basis for ultimate standardization and unification.

    • 专题研究
    • HE Shi-ping, WANG Hong-liang, XU Xue-yi, ZHANG Hong-fei, REN Guang-ming

      2007,26(4):295-309, DOI:

      Abstract:

      Early Paleozoic volcanic rocks in Tianshui and Baoji areas along the eastern segment of North Qilian orogenic belt consists of Hongtubu basaltic lavas and Chenjiahe intermediate-acid volcanic rocks. Geochemical analyses show that Hongtubu basaltic lavas are similar to the intercalated basalts in Chenjiahe intermediate-acid volcanic rocks in characteristics, both fallen in the tholeiite series with high TiO2 (1.50%~2.73%). Their∑REE are 65.97×10-6~133.46×10-6 and 78.04×10-6~175.55×10-6 respectively, both are slightly enriched in LREE [(La/YbN being 2.00~4.40 and 2.71~4.40 respectively],and both have no obvious Eu anomaly or weak Eu negative anomaly(δEu being 0.85~1.10 and 0.85~0.99 respectively). Basalts from two groups are typically characterized by selected enrichment of LILEs, low abundances of HFSEs relative to NMORB, and prominent troughs of Nb and Ta, with low Nb/La ratio(0.28~0.43), which indicates the affinity of these volcanic rocks to island arc tholeiite(IAT). In addition, εNd(t)(+2.22~+4.08)values of basalts suggest that their mantle sources are similar to the depleted mantle source. Zr/Nb=17.21~36.33 and Ce/Nb=5.73~8.17, implying geochemical characteristics of N-MORB. Sr, Nd and Pb isotopes from Hongtubu basalts are similar to those in Chenjiahe basalts in composition. In the diagrams of εNd(t)-(87Sr/86Sr)t, (207Pb/204Pb)t-(206Pb/204Pb)t,(87Sr/86Sr)t-(206Pb/204Pb)t and εNd(t)-(206Pb/204Pb)t for basalts, the data are fallen in the DM, EMⅠand EMⅡ areas, probably with a little crustalontamination, indicating that the magma of basalts might have had a mixed gin.Thentermediate-acid volcanic rocks from Chenjiahe belong to the calc-alkaline series,they have relatively high abundances of REE∑REE=127.51×10-6~276.01×10-6), and are significantly enriched in LREE[(La/YbN= 4.79~13.51]. Most intermediate-acid volcanic rocks show weak Eu negative anomaly (δEu=0.53~1.20). The trace element patterns of Chenjiahe acid volcanic rocks are similar to those of the ocean ridge granite (ORG), with marked troughs of Nb, Ta, Zr and Hf. A synthetic study shows that the Chenjiahe intermediate-acid volcanic rocks in the eastern segment of North Qilian orogenic belt were formed in an island-arc setting, whereas the Hongtubu basalts were formed in an intra-arc rift setting (or an initial back-arc basin setting), probably being products of the early spreading evolution of the island_arc system towards the back-arc basin in the eastern segment of North Qilian during late Early Paleozoic. The results obtained provide evidence for the existence of the trench-arc-basin system at the juncture of Qilian and North Qinling orogenic belts.

    • 宝玉石矿物学
    • YAN Ruogu, QIU Zhili, DONG Chuanwan, LI Liufen

      2009,28(3):292-298, DOI:

      Abstract:

      High grade black jadeite is a kind of upscale and fashionable jade material that has become one of the jadeites characterized by fastest growing values in the past 20 years. Based on a comparison of mineralogical and geochemical characteristics between black jadeites (inky black jades)from different producing areas of the world, the authors hold that the black jadeites currently on the market can be mainly classified into jadeite jade, omphacitic jadeite jade and hornblende jade whose main components are jadeite, omphacite and dark green hornblende respectively. They include black chicken jade, ink jadeite and black kosmochlor from Myanmar and jade negro and galactic gold from Guatemala, with black chicken jades similar to those from Myanmar also seen in Japan and Kazakhstan. The research results suggest that the main mineral composition, jade structure and inclusion characteristic combinations of black jadeite jades from different producing areas have their respective typomorphic natures, which can be used as the distinctive characteristics for their sources.

    • 专题研究
    • CAO Guang-yue, XUE Huai-min, WANG Jin-guang

      2014,33(6):1019-1038, DOI:

      Abstract:

      In this paper,LA-ICP-MS zircon U-Pb dating was carried out for four samples of volcanic rocks from Qingshan Group in Jiaodong area and, as a result, their concordant ages were obtained, which are 119.4±0.9 Ma, 118.2±1.0 Ma,120.2±0.9 Ma and 120.0±0.8 Ma, respectively. The results show that all the volcanic rocks in Jiaodong area were formed from about 120 Ma to 118 Ma in the Early Cretaceous period. The ages of Qingshan Group volcanic rocks from Shandong Province controlled by Tan-Lu fault are similar to those from the Su-Wan segment of the Tan-Lu fault zone,but younger than those around the Tan-Lu fault zone,which indicates that the duration of volcanic eruption along Tan-Lu fault is probably longer than the duration in other areas under the background of lithospheric thinning in eastern China. Geochemically, all the intermediate and acidic volcanic rocks have high K2O, ALK, LREE values and low MgO, TiO2, Ni, Cr, HREE values. According to the geochemical features, the volcanic rocks can be subdivided into trachyte-trachydacite and rhyolite. The trachyte-trachydacite is characterized by LILE enrichment(Rb,Ba,K)and HFSE depletion(Nb,Ta,Ti,P), but the rhyolite exhibits stronger depletion of Ba,Sr and HFSE (Ti,P). Compared with the rhyolite,the trachyte-trachydacite possesses higher Sr and Ba values as well as La/Nb and Ba/Nb ratios,but lower Rb/Ba ratios and δEu values. All these data indicate that they might have been derived from different magma sources. It is inferred that the trachyte-trachydacite rocks were derived from the mixture of the partial melting of the lower crust(Yangtze Craton or North China Craton)and enriched lithospheric mantle. In addition, the rhyolites were related to the partial melting of the lower crust in the regional extension environment and high geothermal anomaly background with crystallization differentiation during the magma evolution.

    • 综述与进展
    • ZHANG Wei

      2014,33(4):747-762, DOI:

      Abstract:

      Cordierite is a mineral material characterized by low thermal expansion coefficient and good thermal shock resistance. Cordierite mineral material is relatively rare in nature, so cordierite is synthesized usually by the method of artificial synthesis. Based on the newest investigation results of synthetic cordierite, this paper deals with the progress of researches on such synthesis methods of cordierite as high purity oxide solid reaction at high temperature, natural mineral solid reaction at high temperature, the utilization of industrial wasted materials, the employment of agricultural wasted materials, the sol-gel and the low-temperature combustion synthesis. At present, the method of natural mineral solid reaction at high temperature is used for the preparation of cordierite in industry. In spite of a lot of advantages, this method also has many disadvantages. Therefore, the development trend of cordierite synthesis seems to solve the problem as to how to apply other synthesis methods to industrial preparation.

    • 宝玉石矿物学
    • GUO Li-he, HAN Jing-yi, LUO Hong-yu

      2006,25(4):349-356, DOI:

      Abstract:

      At present, the infrared transmission spectroscopy is the best technique for determining whether jadeite is polymer-impregnated or not, and the infrared reflectance spectroscopy is a nondestructive and rapid determination method that provides mainly the fundamental frequency vibration spectra data of minerals and shows new application potentials in gemological research, especially in the identification of gem species. The gemological application of IR reflectance spectroscopy and the identification system of IR spectra of gems, including a database of 318 spectra and a searching and identifying program, are described in this paper.

    • 专题研究
    • LIN Guang-chun

      2013,32(4):485-495, DOI:

      Abstract:

      Petrology, geochemical and Nd isotopic data are reported for the Neoproterozoic Danba metabasalt in the Kangdian Rift on the western margin of the Yangtze block. Samples were collected from alkaline basalts, which are enriched in MgO, TiO2, with Mg# being 0.51~0.59. They have high total rare earth elements and show high fractionation between LREE and HREE. The trace elements are characterized obviously by enrichment of Th, Nb, Ta, Zr, Hf and LREE but depletion of Y and HREE. Their geochemical and Nd isotopic characteristics suggest that they are similar to OIB. The basaltic magma was generated in an intraplate setting, and was generated by partial melting of OIB mantle source region, with variable degrees of contamination of SCLM during magma ascending; in addition, some samples might have experienced contamination of the lower crust. These samples reveal some plume magmatism characteristics in petrochemistry, and imply that magmatism was probably related to the Neoproterozoic plume event, which resulted in the breakup of Rodinia supercontinent.

    • ZHANG Kan, ZHU Xiang-kun

      2013,32(4):529-537, DOI:

      Abstract:

      The newly-exposed lower strata of the Xiamaling Formation near Tielingzi Village in Jixian County contain rich siderites. This paper reports the basic geological characteristics of these siderite-rich strata in terms of the field outcrop, petrology and major elements. Studies show that the profile is characterized by black shale interbedded with silty iron-rich layers/siderite concrete layers, and also has minor siltstone. Some iron-rich strata have turned into limonite layers in the outcrop because of intense weathering. Siderite is the main iron mineral phase in the strata. Siderites can form iron concretes, showing micritic or microcrystalline granulitic textures under the microscope, or form silty ferruginous layers with almost a comparable amount of silty quartz; it can also distributed sporadically in siltstone and black shale with relatively coarse particles. There also exists very little siderite residue in weathered limonite layers. The overall features of major elements show that the strata are rich in SiO2, TFe and TOC, but poor in MnO, CaO, MgO, P2O5 and S. Except for ferriciron in weathered layers, there is mainly ferrous iron in the strata. The TOC content decreases in order of siderite concrete, silty iron-rich layer, black shale and siltstone. The correlation diagram between TFe and Al2O3 content shows a negative correlation in iron-rich layers, while a positive correlation between them exists in normal black shale and siltstone, which suggests that iron in the former form originated from the ocean itself, while iron in the latter form originated mainly from terrigenous detritus. In addition, FeO content has a positive correlation with TOC content in fresh samples, which implies that the genesis of siderites may have some relationship with organic matter.

    • Zhou Zheng

      1997,16(1):81-90, DOI:

      Abstract:

      From the discovery of the first new mineral hsianghualite in 1958 to the end of 1995,74 new minerals found in China had been approved by IMA CNMMN. Among them, 2/3 were discovered after 1981. The discovery of new minerals in China has the following features:(1) With the development of analytical methods, the number of new minerals discovered per year increases gradually: from the end of 1950s to 1960s, only one new mineral was discovered every year on the average, whereas from 1980s till now, three new minerals were discovered averagely every year. (2) The structures of many new minerals have been determined. (3) Most of the new minerals are in the lower category, mainly in the monoclinic system, and perfect crystals are rare; hsianghualite has the most abundant crystal faces, whose ideal faces can reach 146. (4) Among those new minerals, silicates take the first place in number, followed by native elements, alloys, and then oxides. (5) The modes of occurrence of new minerals are varied, most of them occurring in oxidized zones of various deposits and deposits related to ma fic or ultramafic rock masses. There are a few new minerals occurring in skarn and placer deposits or even in cosmic dusts and meteorite.(6) The new minerals are characterized by wide but uneven distribution. Till now, new minerals have been discovered in 20 provinces or autonomous regions, especially in Hebei, Qinghai, Inner Mongolia and Henan. The number of new minerals found in North China is larger than that found in South Chine. (7) The number of discoverers of new minerals is in tens. The first discoverer of new mineral is Prof. Huang Yunhui, whereas Prof. Yu Zuxiang is the one who discovered the most numerous new minerals in China, totally disclosing 11 new minerals by himself or together with other experts. Most of the discoverers are members of the Chinese Academy of Geological Sciences, China University of Geosciences, and Institute of Geochemistry, Academia Sinica as well as other educational and scientific research institutions. The discovery of new minerals has promoted the development of mineralogy in China. Tens of discoverers were awardees of the National Natural Sciences Prize or the Science and Technology Progress Prize of the Ministry of Geology and Mineral Resources for the discovery and research results of new minerals in 1980s. More than 60 new mineals discovered in China were collected by the Geological Museum of China, with some of them exhibited in the Minerals and Rocks Exhibiting Room.

    • 其他
    • LUO Yue-ping, DENG Wang-hui, DUAN Ti-yu, WANG Chun-sheng

      2011,30(Z1):181-186, DOI:

      Abstract:

      As more and more treated turquoises appear on Chinese gem market, the authors collected lots of turquoises from different deposits on Chinese gem market in order to sum up the characteristics of the natural turquoises on Chinese gem market. At the same time, different types of treated turquoises were studied to find general difference between them and natural turquoises. The results show that natural turquoise and treated turquoise have different shades of color, inclusions and appearances. IR spectra of both natural and treated turquoises were studied, indicating that there are absorption peaks at 1 735, 1 600 and 1?500 cm-1 in treated turquoises, which are caused by the man-made polymer. If the turquoise is treated by polymer, there are absorption peaks at 1 735, 1 600 and1 500 cm-1 in a turquoise, and this can serve as convincing evidence in this aspect.

    • 专题研究
    • ZHU Xin-you, WANG Yan-li, CHENG Xi-yin, TIAN Ye

      2016,35(1):16-32, DOI:

      Abstract:

      There are several types of xenoliths, such as monzonite, quartz diorite porphyry, black rock and greisen schlieren, in the alkali feldspar granite of the Yaogangxian tungsten deposit, Hunan Province. The xenoliths are different in geological and geochemical characteristics, sources and evolution paths, which implies the genesis and magma evolution history of the Yaogangxian granite. In this paper, the authors studied the petrology, geochemistry of the xenoliths, alkali feldspar granite, and monzonite batholiths formed in late Jurassic period. It is detected that the monzonite inclusion (Ⅰb) came from early crystallization of deep magma chamber similar to the monzonite batholith. The quartz diorite porphyry and black rock xenoliths seem to have been the residue of Precambrian metamorphic rocks in the melting. The greisen schlieren resulted from the transition from the alkali feldspar granite stage to the magma-hydrothermal stage. The fine biotite granite xenolith (Ⅲb) in the quartz porphyry was captured from the supplementary granite which was differentiated from the main magma, or from the granite pluton formed from the supplementary rocks. The granite (Ⅰ) was rich in volatiles, which resulted in strong contamination of the xenoliths, and a certain amount of fluorite, mica, tourmaline and sulfide minerals formed in the xenoliths. The Yaogangxian granite is a product of the intrusion of highly fractionated magma derived from the magma chamber equivalent to monzonite batholith. The quartz porphyry magma directly resulted from the residue of segregation from fractional crystallization of magma chamber, rather than from the alkali feldspar granite of Yaogangxian. It is suggested that the magma evolved in order of magma chamber (main) (coarse monzonite) → fine biotite granite (supplementary) → alkali feldspar granite → magma-hydrothermal transition fluid (tungsten mineralization) → quartz porphyry veins.

    • LI Yu-long, YANG Zhu-sen, TIAN Shi-hong, ZHAO Zhi-yi, LU Shi-yin, ZHANG Yao, LIU Ying-chao

      2015,34(5):648-664, DOI:

      Abstract:

      Two kinds of carbonate hosted Pb-Zn deposits, namely carbonate-rich Pb-Zn deposits and fluorite-rich Pb-Zn deposits, extensively exist in the same Pb-Zn metallogenic belt in the world according to the classification based on gangue mineral assemblages. The relationship between the two kinds of deposits remains unclear. In the middle part of the 'Sanjiang' metallogenic belt in the Tibetan Plateau, the Dongmozhazhua carbonate-rich Pb-Zn deposit and the Mohailaheng fluorite-rich Pb-Zn deposit occur in the same carbonate-hosted Pb-Zn ore concentration area. In the two deposits, the carbonate strata are host rocks, the thrust faults are the main ore-controlling structures, the main orebody attitudes are of stratabound type, and sphalerite and galena are the main ore minerals. However, calcite and dolomite are the main gangue minerals in the Dongmozhazhua deposit while calcite and fluorite are the main gangue minerals in the Mohailaheng deposit. The geochemical features of rare earth elements (REE) in calcium-bearing minerals are different in the two deposits. The REE values of calcite in the Dongmozhazhua deposit are mainly characterized by obvious fractionation of LREE and HREE, enrichment of LREE, negative Eu anomalies and 'V'_shaped curves of chondrite-normalized REE patterns with right deviation. In contrast, the REE values of calcite and fluorite in the Mohailaheng deposit are chiefly characterized by no obvious fractionation between LREE and HREE, negative Eu anomalies and 'M'_shaped curves of chondrite-normalized REE patterns with right deviation. The total concentrations of REE (∑REE) of calcite (0.46×10-6~10.79×10-6) in the Dongmozhazhua deposit are higher than those in the Mohailaheng deposit (0.25×10-6~5.88×10-6). The geochemistry of the REE indicates that calcium-bearing minerals in the two deposits were all precipitated from a kind of hydrothermal fluids which had nothing to do with igneous activities. The salinity and reducibility of the fluids decreased with the sulfide precipitation. The two kinds of deposits had similar hydrothermal fluids; nevertheless, there existed another kind of fluid for the Mohailaheng deposit, which was a kind of fluorine-rich fluid from deep metamorphic basement. This fluorine-rich fluid controlled the location of the fluorite-rich carbonate hosted Pb-Zn deposits and could be used to explain the phenomenon why this kind of Pb-Zn deposits were more easily precipitated near the main thrust faults and the lowest carbonate strata in the region. The result achieved by the authors could answer the question why the carbonate-rich Pb-Zn deposit and the fluorite-rich Pb-Zn deposit can occur in the same region and same time in the world.

    • ZHANG Wen, WU Tai_ran, HE Yuan_kai, FENG Ji_cheng, ZHENG Rong_guo

      2010,29(6):719-731, DOI:

      Abstract:

      Beishan area is located in the west of Inner Mongolia and Gansu Province, which is the conjunction zone of Tarim plate, Sino-Korea plate and Kazakhstan plate and plays an important role in the study of the Central Asia Orogenic Belt (CAOB). The relationship of the three plates is so complicated that there exists much controversy concerning Paleozoic tectonic evolution in this area. Granitoids, especially Late Paleozoic granitoids, are widely distributed in Beishan area, which are of great importance in the study of Paleozoic magmatic evolution. Through analyzing the spatial and temporal distribution of the Late Paleozoic granitoids, we can find the relationships between these granitoids and explore the crust-mantle interaction in Beishan area during Late Paleozoic, which is important for determining the geotectonic evolution of this area. In the southern belt of Beishan, the most important tectonic event in Permian is the formation of Yin'aoxia rift zone, which makes the study of Late Paleozoic evolution more complex. The results of studying Xijianquanzi granite lying in the southern belt of Beishan in such aspects as major elements, trace elements, REE and LA-ICP-MS zircon U-Pb geochronology have provided new evidence for regional tectonics. The LA-ICP-MS zircon U-Pb age of Xijianquanzi granite is 266.1±2.2 Ma, and the Hf modal ages are 746~871 Ma. εHf(t) values are +1.3~+4.7 with an averageof +2.7, which implies the mixture of crustal and mantle.derived magmas. This feature coincides with that of other areas in the Central Asia Orogenic Belt (CAOB). Therefore, the granites in the belt may have similar magma sources. The granitic body mainly consists of monzonitic granites which belong to alkaline series with high content of SiO2 (74.33%~76.67%), Na2O+K2O (9.26%~9.57%, NK/A=0.9~1.08) and K2O (Na2O/K2O<1) . In addition, chondrite-normalized REE patterns and primitive mantle normalized geochemical patterns of all samples are approximately parallel to each other, which shows that they evolved from the same magma source. Chondrite-normalized REE patterns of the intrusive body are of “V" types and show enrichment of light rare earth elements (LREE) with low ratio of (La/Yb) N (3.18~5.29) and negative Eu anomalies (δEu =0.10~0.16). Except for Eu, the abundance of rare earth elements are demonstrably over 10 times that of chondrite. Depletion of Nb, Ba, Sr, Ti, P and enrichment of Rb, Th, K can be seen in the spidergram. Based on regional geological and geochemical characteristics, the authors have reached the conclusion that the Xijianquanzi intrusive body is an alkali-rich potassium-high granite which is a mixed product of crustal and mantle-derived magmas and was formed at the stage of rifting in the post-collisional extensional period, affected greatly by Yin'aoxia rift zone. This implies that the area entered into the stage of rifting in Middle Permian.

    • 综合资料
    • ZHANG Xi-huan, REN Yu-feng

      2008,27(2):135-151, DOI:

      Abstract:

      本文以表格的形式列举了经国际矿物学协会(IMA)新矿物与矿物命名委员会(CNMMN)批准、并于2003年度正式发表的新矿物共55种,其中硅酸盐31种,磷酸盐5种,砷酸盐2种,硫酸盐4种,硫化物3种,碳酸盐2种,钒酸盐2种,硼酸盐1种,硒化物1种,硫盐1种,氧化物1种,氢氧化物1种,复杂卤化物1种.文中表格依次列出了矿物的中外文名称及化学式、晶系及晶胞参数、主要粉晶数据、物理性质、光学性质、产状及共生(伴生)组合等.

    • 中国大陆环境典型斑岩型矿床成矿规律和找矿模型:研究进展(Ⅱ)专辑
    • ZHOU Jin-sheng, JI Xian-hua, YANG Zhu-sen, HOU Zeng-qian, ZHUANG Liang-liang

      2015,34(4):557-567, DOI:

      Abstract:

      In the magma-related deposits, the ore-forming plutons generally experienced high-degree evolution and differentiation, so its petrologic and geochemical characteristics can only reflect the final state of magma evolution. The evolution of ore-hosted magma and the geochemical behavior of main metallogenic elements in the evolution remain unclear. However, the study of contemporaneous and sympatric magmatic rocks provides a potential solution for this question. Here the authors made a case study of the northern Gangdise Pb-Zn ore belt in Tibet formed in the early period of continental collision. Based on the statistical study of lots of published geochemical analyses of magmatic rocks from the Gangdise belt, this paper presents the evolution of magma and its control of metallogenesis. The results suggest that, besides the crystallization differentiation of magma itself, crustal contamination was another factor controlling the evolution from basic magma to acid magma during differentiation. It is also found that most of the magmatic rocks formed in the early period of continental collision are less oxidized and less hydrous; nevertheless, when magma evolved to the middle and late period, the oxidation of magma increased with progressive evolution. Mantle-derived magmas are enriched in S and H2O, which experienced underplating at the base of Zn-enriched crust materials and induced partial melting. Crust-derived magmas experienced high-degree evolution, and finally resulted in the formation of the northern Gangdise Pb-Zn ore belt.

    • 专题研究
    • SHI Jian-rong, LIU Fu-lai, LIU Ping-hua, MENG En, LIU Chao-hui, YANG Hong, WANG Fang, CAI Jia

      2014,33(1):29-50, DOI:

      Abstract:

      Eclogites and blueschists are exposed mainly as slices or variable tectonic lenses within garnet phengite schists in Habutengsu area, southwestern Tianshan Mountains, Xinjiang. In this paper, petrography, mineralogical chemistry and p-T conditions of the eclogites and blueschists were studied in detail. The eclogites could be divided into four groups, i.e., glaucophane eclogites, paragonite eclogites, epidote eclogites, and glaucophane-garnet amphibolites (retrograde eclogites), whereas blueschists could be divided into three groups, namely glaucophane-bearing garnet-muscovite-albite schists, garnet-muscovite-glaucophane schists and garnet-muscovite-glaucophane-quartz schists. Major mineral assemblages are Grt+Omp+Pg+Ep for the fresh eclogites, Grt+Gln+Amp for the retrograde eclogites, and Grt+Gln+Phe+Pg+Ab+Qtz for the blueschists. Porphyroblastic garnets show perfect prograde zoning, with XMn and XFe deceasing and XMg and XCa increasing from the core to the rim, which indicates a process of increasing temperature and prograde metamorphism. According to the paragenetic assemblages of inclusions within garnet as well as in matrix, four stages of metamorphism were recognized, viz., pre-peak lawsonite-blueschist facies metamorphic stage, peak eclogite facies stage (t=543~579℃, p=1.5~1.6 GPa), retrograde epidote-blueschist facies stage (t=~450℃, p<1.0 GPa), and post-peak retrograde blueschist-greenschist facies stage (t<400℃, p<0.5 GPa). The p-T pseudosection calculation shows that the peak metamorphic conditions were 520~550℃ and 1.7~1.9 GPa for the eclogites, and 520~620℃ and 1.7~2.3 GPa for the blueschists, similar to the results of traditional geothermobarometer. Previous researchers reported coesites preserved in some eclogites and country rocks, which suggested that partial eclogites and partial country rocks within the southwestern Tianshan metamorphic belt underwent UHP metamorphism, but this conclusion is inconsistent with the results constrained by the eclogites in this study. The possible reasons might be as follows: ① the eclogites were affected by later thermal events, which led to the partial variation of both minerals and whole rock compositions. On the basis of the changed whole-rock compositions, the traditional thermobarometer Grt-Cpx-Phe and phase equilibrium simulations certainly show relatively low pressure results, and ② not all eclogites from the southwestern Tianshan underwent UHP metamorphism, and HP-UHP eclogites may represent the metabasites subducted to different depths.

    • 综合资料
    • AI Yu-jie, FAN Guang

      2015,34(1):117-128, DOI:

      Abstract:

      This paper presents a collection of 31 new uranium minerals approved by the Commission on New Minerals, Nomenclature and Classification (CNMMN) of the International Mineralogical Association (IMA) between January 2003 and December 2013. It lists the mineral names both in English and Chinese together with their structural formulae, crystal structure data, physical and optical properties, localities and modes of occurrence. The crystallochemical classification and characteristics of these new minerals are discussed. Some suggestions are put forward concerning China's uranium minerals research work in the hope of providing valuable reference for China's uranium researchers.

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    Editor:Zengqian Hou

    Started in:1982

    ISSN 1000-6524

    CN 11-1966/P