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  • 1  The recommendation of a systematic list of mineral abbreviations
    SHEN Qi-han
    2009, 28(5):495-500.
    [Abstract](11292) [HTML](0) [PDF 316.09 K](24603)
    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.
    2  A preliminary study of typomorphic characteristics of different kinds ofblack jadeite jades in the world
    YAN Ruogu QIU Zhili DONG Chuanwan LI Liufen
    2009, 28(3):292-298.
    [Abstract](10455) [HTML](0) [PDF 1.20 M](13744)
    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.
    3  Mineral-Melt Element Partition Coefficients: Data and Major Variation Regularities
    Gan Guoliang Yichang Institute of Geology Mineral Resources Chinese Academy of Geological Sciences Department of Grologicol Atmospheric Sciences lows State Univeraity Ames IAS U.S.A
    1993, 12(2):144-181.
    [Abstract](9000) [HTML](0) [PDF 12.09 M](23160)
    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.
    4  Geochemical characteristics and tectonic setting of Qitianling A-type granitic pluton in southeast Hunan
    BAI Dao_yuan CHEN Jian_chao MA Tie_qiu WANG Xian_hui
    2005, 24(4):255-272.
    [Abstract](8082) [HTML](0) [PDF 4.98 M](3887)
    Abstract:
    Qitianling composite granitic pluton is in the middle south of the southeastern Hunan ore concentration area. The Middle Jurassic Qitianling granite, the main intrusive body of Qitianling pluton, is studied in this paper. The Qitianling granite is composed of hornblende biotite granodiorite, hornblende biotite monzonitic granite and biotite monzonitic granite. SiO2 content increases from early to late granitic units, varying in the range of 65.92%~75.68%. The rocks are potassium-high (K2O=4.10%~5.27%, 4.86% on average) and alkali-rich (Na2O+K2O=7.12%~8.24%, 7.85% on average) ones, and have an average K2O/Na2O value of 1.63, ACNK values of 0.90~1.05 (0.96 on average) and KN/A values of 0.71~0.89 (0.78 on average), thus belonging to metaluminous to weakly peraluminous granitoids of shoshonite series and K_high calc_alkaline series. The rocks have an average ΣREE of 375.6 μg/g and show evident negative Ba,Nb, Sr, P, Ti and Eu anomalies as well as positive U, Th, Nd, Zr, Sm and Y anomalies, suggesting evident fractional crystallization. They have ISrvalues of 0.708?54~0.712?81, εNd (t) values of -5.05~-7.57 and tDM ages of 1.35~1.56 Ga, which is lower than the background age of granitoids in Hunan and Guangxi (1.8~2.4 Ga) and the region_al basement's age (1.7~2.7 Ga), implying participation of mantle materials. Various oxide and trace element diagrams for discrimination of structural environment reveal that the Qitianling granite was formed in a post_orogenic extensionalstructural environment. The authors consider that the early Yanshanian tectonicsetting in southeast Hunan and South China is a post_orogenic one instead of an intracontinental rift.
    5  On the Rules for Writing Adjectival Modifiers in the Mineralogical Nomenclature in Chinese
    Luo Gufeng
    1989, 8(4):374-380.
    [Abstract](7947) [HTML](0) [PDF 2.89 M](3767)
    Abstract:
    This paper discusses the confusion in writing forms of adjectival modifiers for mineralogical nomenclature, especially in Chinese, and analyses the reasons resulting in this situation. Based on the above analyses, the author proposes a unified rule for writiag adjectival modifiers in the mineralogical nomenclature in Chinese.
    6  The Comparison of the Chrome Spinets Composition between Meteorites and the some Chromite Deposites
    郑新华 黄耀民
    1985, 4(3):202-209.
    [Abstract](7846) [HTML](0) [PDF 4.57 M](3385)
    Abstract:
    By way of comparing the composition of meteorite chrome spinets with the chrome spinets in some chromite deposits may raise the understanding of the genesis of the earth chramite. The average composition of chondrite chrome spinet can represent that of all sort meteorites, hence it can be used as a standard for the earth chrome spinets. The characteristic of the composition of meteorite chrome spinets is related with the high ferrous medium, extremity low pressure, reducing condition, as well as undergone a very slow process of cooling and crystallization. The variation of the chemical composition of chrome sninels in the various meteorites is similar to that of the main kind of earth at a depth of about 50-100Km. chromite deposits (i.g.ophiolite yype and layer).The coefficient of the ferrous in .the chromium end member indicates the better differentiation of the begin- ring substa}ate.
    7  Basic Properties of Environmental Mineral Materials: Natural Self-purification of Inorganic Minerals
    LU An-huai
    2001, 20(4):371-381.
    [Abstract](7545) [HTML](0) [PDF 2.96 M](3749)
    Abstract:
    Natural self-purification, a potential mechanism in nature whereby mankind and the Earth are interrelated with each other, has been playing an increasingly important role in the field of harnessing contamination and remedying environment. Neverthelsss, the self-purification of natural minerals widely occurring in the inorganic world has been largely ignored. This means that only half of the potential self-purification capabilities offered by nature are recognized, exploited and utilized. Utilizing most of the natural self-purification functions of both the organic and the inorganic world is a reflection of implementation of the whole self-purification function. Pollutant treatment by natural minerals is based on the law of nature and reflects natural self-purification function in the inorganic world, similar to that of the organic world. The purification function of natural minerals for reducing pollutants is reflected mainly in the basic properties of environmental mineral materials. The basic properties of this function include surface adsorption, modified porous filtration, defects of crystal structure, ionic exchange, chemical activation, physical effect and micro-effect at nanometre levels as well as mineralogical-biological interactions. A series of case studies related to the natural self-purification, which were mostly completely by our group, are discussed in this paper. Mineralogical method and biological method are well matched in pollutants disposal and jointly constitute a natural system of self-purification in terms of pollution treatment and environmental remediation in the spheres of interaction between mankind and the earth surface.
    8  40Ar/39 Ar Chronology of Intrusive Rocks from Tongling
    Wu Cailai
    1996, 15(4):299-306.
    [Abstract](7516) [HTML](0) [PDF 2.31 M](3934)
    Abstract:
    Ar/39 Ar isotopic chronologic studies of intrusive rocks from Tongling area show that ages of these rocks are all younger than 140Ma and belong to Late Yanshanian period, with granodiorite, quartz monzodiorite, pyroxene monzodiorite and gabbro diabase being 139.8-137Ma, 137-135.8Ma, 138.2-136.6Ma and 133.7Ma respectively. On the basis of 40 Ar/39 Ar isotopic chronologic studies of these intrusive rocks, the authors have also dealt with their K Ar and Rb Sr isotopic ages, and pointed out that the age error was caused by the late hydrothermal alteration and the mixture between mantle magma and crustal magma. In addition, the mineralization ages are found to be close to the smaller ages in 40Ar/39 Ar age spectra, which is in accord with the regional metallogenic character that mineralization took place later than magmatic activity.
    9  Mineralogy, mineral chemistry and genesis of the Hongyuntan iron deposit in East Tianshan Mountians, Xinjiang
    ZHANG Li-cheng WANG Yi-tian CHEN Xue-feng MA Shi-qing WANG Zhi-hua YU Chang-fa
    2013, 32(4):431-449.
    [Abstract](7163) [HTML](0) [PDF 18.22 M](32536)
    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.
    10  An impedance spectral analysis of electric characteristics of pyrophyllite dehydration at high temperature and high pressure
    DAI Li-dong~
    2005, 24(3):216-220.
    [Abstract](6469) [HTML](0) [PDF 1.35 M](3964)
    Abstract:
    The electric conductivity of pyrophyllite was measured by means of Sarltron-1260 frequency and phase impedance spectroscopic analyzer under the condition of 1.0, 2.0 GPa and 873~1223 K and on the basis of microcosmic mechanism analysis. The experimental results indicate that (1) the electric conductivity of the sample depends on frequency, (2) the relationship between electric conductivity and temperature is in linear accord with the Arrenhius equation,and (3) the dehydration temperature of pyrophyllite is 1074 K and 1101 K at1.0 GPa and 2.0 GPa, respectively. A conclusion different from previous conclusions has been drawn, which holds that an inflexion appears after dehydration.
    11  The Origin and Geochemical Characteristics of Upper Sinain_Lower Cambrian Black Shales in Western Hunan
    Wu Chaodong Yang Chengyun
    1999, 18(1):26-39.
    [Abstract](6467) [HTML](0) [PDF 2.81 M](3688)
    Abstract:
    This paper deals with the formation conditions of black shales based on such analytical techniques as ICP_MS, GC_MS, isotope, organic carbon, element facies and micropetrology. Studies show that the Upper Sinian_Lower Cambrian black shales were formed in an anoxic environment, and the organic sources were algae and fungi (Thallophyta). The paper points out five geochemical indicators of anoxic environment. The organic matter, especially lipids, can be well preserved in an anoxic environment. Black shale is also an indicator of the oceanic anoxic event. During the slow degradation of organism, the organic matter absorbed and combined many elements. At the early diagenetic stage, the organic matter was decomposed, and some elements were remobilized. Hence the elements exhibit multi_stage enrichment and varied forms. The key factor is the adsorption of organism and the combination with the organic matter. The strata of Ni_Mo, coal stone, barite and phosphorite deposits are controlled by the change of sea level, and the ore_bearing sets are developed in the transgressive series and condensed sections. The black shales are characterized by high content of Ni, Mo and Mn, lower total REE, comparative enrichment of HREE, and negative Ce anomaly. Geochemical and REE features indicate that black shales were deposited in an epeiric sea environment.
    12  Geochemical characteristics and tectonic environment of Hongtubu basalts and Chenjiahe intermediate-acid volcanic rocks in the eastern segment of North Qilian orogenic belt
    HE Shi-ping WANG Hong-liang XU Xue-yi ZHANG Hong-fei REN Guang-ming
    2007, 26(4):295-309.
    [Abstract](6401) [HTML](0) [PDF 10.59 M](13863)
    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.
    13  High-precision measurements of Fe isotopes using MC.ICP-MS and Fe isotope compositions of geological reference materials
    Nick S. Belshaw
    2008, 27(4):263-272.
    [Abstract](6210) [HTML](0) [PDF 756.61 K](4623)
    Abstract:
    Techniques for high_precision measurements of Fe isotope ratios using MC-ICP-MS at both low-and high_resolution modes have been reported in detail, which includes assessments of isobaric inferences, matrix effects, concentration effects and long_term repeatability. The external precision for the methods established at both low-and high-resolution modes are better than 0.5 ε/amu, and the results obtained under the two modes are consistent with each other. Using the techniques developed, the Fe isotope compositions of national geological reference materials GBW 07105 (basalt powder) and GBW 07111 (grano-diorite powder) have been measured. Relative to IRMM-14, the Fe composition for GBW 07105 is: ε57Fe=1.9±0.3(2σ),ε56Fe=1.3±0.2(2σ),ε57/56Fe=0.6±0.1(2σ); and ε57Fe=1.8±0.4(2σ),ε56Fe=1. 2±02(2σ),ε57/56Fe=0.6±0.1(2σ) for GBW 07111.
    14  An Experimental Study of Adsorption Capacity of Montmorillonite, Kaolinite and Illite for Heavy Metals
    HE Hong-ping GUO Jiu-gao ZHU Jian-xi YANG Dan
    2001, 20(4):573-578.
    [Abstract](5989) [HTML](0) [PDF 1.06 M](3838)
    Abstract:
    The experimental study on the adsorption capacity of montmorillonite, kaolinite and illite for Cu2+,Pb2+, Zn2+, Cd2+and Cr3+was conducted under the conditions of pH=4,t=23℃and very low concentrations of heavy metals. In this study, some means were used for the purpose of keeping the original concentrations of heavy metals unchanged and increasing the amount of heavy metals by adding heavy metals_bearing solution into the reaction systems. The adsorption capacities of the three clay minerals for the five heavy metals are found to be in order of montmorillonite > illite > kaolinite. Their adsorption capacities are mainly controlled by their CEC. XRD results of Cu_montmorillonite and Cr-montmorillonite show that Cu2+and Cr3+have entered the interlayer of montmorillonite by cation exchange with Ca2+. Also, adsorption capacities of each mineral are different for different heavy metals: the adsorption capacities of montmorillonite, kaolinite and illite for different heavy metals are in order of Cr3+>Cu2+>Zn2+>Cd2+>Pb2+, Cr3+>Pb2+>Zn2+>Cu2+>Cd2+and Cr3+>Zn2+>Cd2+>Cu2+>Pb2+respectively.
    15  Mineralogical and petrological characteristics of Taishan Jade
    HOU Xu WU Rui-hua WANG Shi-qi SHI Wei
    2011, 30(Z1):169-174.
    [Abstract](5619) [HTML](0) [PDF 897.09 K](3641)
    Abstract:
    In this paper, Taishan Jades were tested by such means as electron microprobe analysis (EPMA), X-ray diffraction (XRD), whole rock chemical analysis and Fourier transform infrared spectroscopy (FTIR). They were discussed systematically in the aspects of colors, mineral composition, chemical composition, trace elements, texture, structure and physical properties. There are three types of Taishan Jades, namely Taishan green jade, Taishan black jade and Taishan piebald jade. The jade consists mainly of antigorite, with minor magnetite, carbonate, talc, chlorite, orthorhombic pyroxene, mica, pyrite, limonite and vaesite. The minerals in Taishan jades were formed in order of schistose serpentine→veined serpentine→talc→veined carbonate. The color of Taishan green jade and piebald jade is caused by Fe2+, and the color of Taishan black jade results from particles of magnetite. Taishan Jades consist of more Cr and Ni in comparison with Xiuyan Jades.
    16  Zircon U-Pb age and geochemistry of Mesozoic intermediate and acidic volcanic rocks from the Shandong segment (Jiaodong area)of the Tan-Lu fault
    CAO Guang-yue XUE Huai-min WANG Jin-guang
    2014, 33(6):1019-1038.
    [Abstract](5444) [HTML](0) [PDF 21.14 M](11348)
    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.
    17  LA-ICP-MS zircon U-Pb ages of Xijianquanzi alkali-rich potassium-high granites in Beishan, Gansu Province, and their tectonic significance
    ZHANG Wen WU Tai_ran HE Yuan_kai FENG Ji_cheng ZHENG Rong_guo
    2010, 29(6):719-731.
    [Abstract](5272) [HTML](0) [PDF 546.32 K](6927)
    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.
    18  The mechanism of applying tourmaline to purifying Cu~(2+)-doped waste water
    TANG Yun_hui WU Rui_hua ZHANG Xi_huan
    2002, 21(2):192-196.
    [Abstract](5068) [HTML](0) [PDF 1.01 M](3191)
    Abstract:
    This paper deals with the mechanism of applying tourmaline to purifying Cu 2+_doped waste water based on the study of absorbing Cu2+ ion by tourmaline in water. Factors affecting the absorption of Cu2+ ion in solution, such as diameters, quantity of tourmaline particles, and experimental conditions (pH value, temperature, stirring situation) are studied. The purifying mechanism of tourmaline lies in the existence of electrostatic field around tourmaline particles, which attracts Cu2+ ion and causes Cu2+ to combine with OH-, the dissociation product of hydroxyl at the surface of tourmaline, thus forming precipitation on tourmaline and attaining the aim of purification.
    19  Ar-Ar and zircon SHRIMP geochronology of hornblendite and diorite in northern Darhan Muminggan Joint Banner, Inner Mongolia, and its geological significance
    LI Jian_feng ZHANG Zhi_cheng HAN Bao_fu
    2010, 29(6):732-740.
    [Abstract](4632) [HTML](0) [PDF 817.94 K](4502)
    Abstract:
    The northern Darhan Muminggan Joint Banner of Inner Mongolia, geotectonically crossing two geological-structural units, is divided into two parts by Bayan Obo-Chifeng deep fault (plate boundary fault). To the south of the deep fault is the North China block, and to the north is the accretion zone at the northern edge of North China plate. An important magmatic arc belt mainly composed of diorite, quartz diorite, tonalite and granodiorite is developed near Bart-Obao on the north side of Bayan Obo-Chifeng deep fault. In this paper, precise SHRIMP zircon U-Pb dating and hornblende 40Ar/39Ar dating defining the emplacement age of the intrusion and its thermal evolution history were conducted for inclusions of diorite and hornblendite hosted in granodiorite, and the constraints on Early Paleozoic subduction-collision event of the Paleo-Asian Ocean in central Inner Mongolia were provided from isotope geochronology. SHRIMP U-Pb zircon ages of the two diorite samples are 453±3 Ma and 446.8±5.3 Ma, and hornblende 40Ar/39Ar plateau ages are 459.2±2.4 Ma and 442.9±4.2 Ma. SHRIMP zircon U-Pb dating results indicate that the island arc intrusive rocks were formed around 450 Ma, resulting from the Middle-Late Ordovician (or earlier) oceanic subduction event. The results of SHRIMP zircon U-Pb dating are basically in accordance with those of hornblende conventional 40Ar/39Ar dating method, which suggests the crystallization and rapid cooling after the emplacement of the magma and may reveal collision between the Baoerhantu-Bainaimiao island arc zone and the North China plate. The dating results of the diorite imply that tectonic heat events after the emplacement and the cooling of the intrusive body did not affect the hornblende Ar-Ar closed system, and hence strong tectonic heat events did not occur later.
    20  Composition characteristics of Qiantian Stone
    YE Dong ZHAO Xu_gang ZOU Yu ZU En_dong WANG Lei_lei
    2010, 29(2):219-224.
    [Abstract](4504) [HTML](0) [PDF 2.01 M](4118)
    Abstract:
    Qingtian Stone from Qiantian County of Zhejiang Province is one of the famous “four seal stones" in China. Using such means as thin-section analysis, XRD and SEM/EDX, the authors systematically studied chemical composition and mineral composition of some typical species of Qingtian Stone. Some conclusions have been reached: ① Minerals of the selected samples are mainly composed of microscaly aggregates. ② Four types of Qingtian Stones, namely Fengmenhuang, Huangjinyao, Dengguangdong and Honghuadong, are almost exclusively composed of pyrophyllite, with Honghuadong stone also containing a small amount of ilmenite. ③ Fengmenhei and Zitandong stones are mainly comprised of pyrophyllite and sericite; in addition, Fengmenhei stone also contains a small amount of ilmenite, whereas Zitandong stone also contains hematite. ④ Lanxing, Zhuyoudong and Jiangyoudong stones are composed of pyrophyllite and illite, with Lanxing stone also containing a little illite and cryptocrystalline quartz, and Zhuyoudong stone also containing hematite. ⑤ Zhenzhudong stone is almost exclusively composed of andalusite and pyrophyllite. ⑥ Shanpaolü stone is mainly made up of sericite.

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