Abstract:Dioritic enclaves are widely distributed in Badashi biotite-monzogranite of the East Tianshan Mountains. These dioritic enclaves and their host granite are different in mineral association, but species of the same mineral within them are similar to each other. In comparison with the host granite, the dioritic enclaves are higher in Fe, Mg, Ti, Ca and richer in HREE, Sr, but lower in Na, K, Si and poorer in Ba, Th, Hf, Zr. Zircon LA-ICP-MS U-Pb dating gave ages of 301±1 Ma and 298±2 Ma for the dioritic enclaves and their host granite, respectively, indicating their Early Permian emplacement. The dioritic enclaves and their host granite have positive in εNd(t)（＋4.15 and ＋3.06）values and relatively low (87Sr/86S r)i（0.70412 and 0.70475） with fairly similar model ages tDM（812 M and 944 Ma, respectively). It is suggested that the dioritic enclaves and their host granite were derived from the same parental magma that resulted from partial melting of the Neoprot-erozoic depleted-mantle-sourced juvenile crust. Petrologic, geochemical and isotopic studies prove that the Badashi dioritic enclaves are autoliths and the earlier products generated by crystal fractionation of the host granite parental magma

Abstract:Located in Tongren of Qinghai Province, the Longwuxia Gorge ophiolite lies at the juncture between West Qinling and Middle Qilian orogenic belts and is composed of mantle peridotite (dunite, serpentinized dunite), ultramafic cumulate units(clinopyroxene-peridotites, olivine-pyroxenites), mafic cumulate units(olivine-bearing gabbro, gabbro etc.) and diabases. All these units are in contact with faults and have been weakly altered. Polarized light microscope studies of thin sections reveal that the crystallization sequences is Ol→Cpx→(Opx)→Pl, consistent well with the marked SSZ-type ophiolite crystallization sequence. EPMA analyses of the minerals show that olivines belong to the chrysolite family, and clinopyroxenes mostly have the composition similar to that of augite and diopside. Discrimination diagrams based on clinopyroxene geochemical data indicate that ophiolite originated in a compression tectonic background related closely to volcanic-arc. REE concentrations of most samples assume the chondrite-normalized distribution pattern with weak LREE enrichment, which is very different from the pattern of MORB. The enrichment of large ion lithophile trace elements (e.g., Ba, Rb and Sr) and the depletion of Nb, P are similar to things of the subduction zone components. High field strength elements discrimination diagrams also prove the above conclusion. In addition, the ophiolite is supposed to have b een derived from a mature island arc tectonic environment, with the participation of some continental crust materials during the formation process.

Abstract:Permian adakitic granodiorite and quartz-diorite in Bayinwula of Sonid Left Banner are distributed on the northern side of the Erlian-Hegen Mountain ophiolite zone. The 1∶200000 regional geological survey has assigned it to Late Variscan intrusive mass(γδ4(3) ). Studies show that the rocks have characteristics of high aluminum (Al2O3=13.69%～16.48％）, higher sodium（Na2O＝3.53%～4.58％）, lower potassium（（K2O＝2.12%～4.10％）and higher strontium（Sr＝425.1×10-6～645.2×10-6）, SiO2=62.13%～72.87％，Y＜18×10-6（7.23×10-6～14.29×10-6），δEu＝0.71～0.83. The fractionation of light-weight thulium is sharp and the partition curve of thulium forms a right-oblique model. Europium anomaly is not conspicuous, suggesting typical adakitic rock. The spidergram of traced elements relative to the original mantle obviously shows a Sr peak and a Nb valley, and the original earth mantle standard curve is in accordance with that of adakites but obviously different from things of island arc andesite, dacite and rhyolite and continental arc andesite, dacite and rhyolite. The zircon U-Pb age of granodiorite is 256.1±0.9 Ma, implying a product of Early Permian magmatic movement. Mg# is quite high（＞50）, indicating that the northward subduction of the Late Paleozoic oceanic crust experienced partial melting and formed adakitic melt at 75～85 km (the transitional point of amphibolites facies and eclogite facies) , which then intruded the earth's crust and eventually formed adakites.

Abstract:Cenozoic volcanic rocks are distributed in Songxi area of northwestern Qiangtang within northern Tibet, a marine volcanic rock association composed of andesite, dacite and rhyolite belongs to the calc-alkaline-high K calc-alkaline series. The rocks have high large-ion lithophile elements LIL and LREE, low HF SE, and relatively depleted Nb, Ta, Ti, reflecting features of terrigenous magma. SiO2 contents of basic volcanic rocks are less than 53%, suggesting that bas al tic andesite in Songxi area was not entirely produced by direct partial melting from the continental crust generation, and that the formation of basaltic andesite must have had the participation of a small amount of mantle materials. Eunegative anomalies are not obvious, implying that magma was derived from the thickening of the lower continental crust resulting from the collision and long-term squeeze between the Indian plate and the Eurasian plate, which led to the shortening and thickening of the continental crust in the northern part of Qinghai-Tibet plateau, including Qiangtang area. The northward subduction of the Lhasa block of continental lithosphere and the underplating of upwelling asthenosphere materials in the Qiangtang landmass triggered off the formation of the thickened lower crust through partial melting

Abstract:Corundum megacrysts (sapphires) hosted by Changle Cenozoic basalts of Shandong Province contain various melt inclusions, whose compositions are of significance in understanding the mantle metasomatism beneath the North China Craton and the parent magma of the corundum megacrysts. Based on petrographic observation and detailed laser Raman analysis, the authors identified two types of melt inclusions: one is primary melt inclusion rich in carbonates and sulfates and the other is secondary melt inclusion containing sulfates and chloride, with CO2 and H2O existent in both of them. This is the first time that sulfate and carbonate are recognized in fluid/melt inclusions from basalt-hosted corudum megacrysts. The compositions, combined with existing isotopic compositons of noble gases and microthermometry of the inclusions, imply that they are a kind of carbonatite that propably originated from metasomatized mantle. The authors thus hold that the mantle beneath the North China Craton might have experienced metasomatism of carbonates and sulfates-bearing melts (carbonititic magma) besides silicic melts. The carbonates and sulfates identifed in primary inclusions suggest that they must have played an important role in corundum crystallization. The corundums probably resulted from the interaction between mantle derived carbonatites andsilicic magmas/rocks, and were transported to the surface by subsequent basaltic lava

Abstract:Based on field investigation, microscopic and scanning electron microscopic observation, X-ray diffraction, microprobe analysis, salinity and composition measurement of fluid inclusions and isotopic composition measurement of S, O and H, the authors studied some genetic mineralogical properties of sphalerite from the Fankou Pb-Zn ore district in Guangdong Province. The results suggest that there are three generations of sphalerite in this ore district formed respectively at three stages of the hydrothermal Pb-Zn sulfide ore-forming period. These three generations of sphalerite show remarkable differences in such aspects as mode of occurrence, paragenesis, apparent color, morphology, cleavage development, unit cell parameter, Fe content, composition and salinity, δ18O％ and δD％ of fluid inclusions, δ34S‰ and fractionation equilibrium temperature with galena. The evolutional properties of the ore-forming fluid from the first stage to the third stage are as follows: the temperature and salinity varied from low through high to low again; the compositions of the ore-forming fluid changed from Na+-Ca+-Cl- through K+-Ca+-Cl- to Na+-Ca+-Cl- again. The values of δ18O, δD and δ34S decreased , but the decreasing was much more drastic from the second to the third stage than from the first to the second stage, implying that a portion of newly-produced solution with much lower values of δ18O, δD and δ34S participated in the ore-forming fluid during the third stage. It is thus held that the ore_forming fluid should be a kind of mixed-source hot brine heated by Yanshanian regional magmatic event, with a portion of magmatic-hydrothermal solution participating in the formation of the hot brine at the intermediate-late ore-forming stage

Abstract:The composition of Machangjing alkali-rich porphyry was analyzed and the data obtained are reported in this paper. The results show that the porphyry has characteristics of potassium-high calc-alkali series or shoshonite series, with SiO2 being 61.56％～71.63％, averaging 67.30％(≥56%); Al2O3 13.38%～17.18％, averaging 15.44% (≥15%); K2O 3.36％～8.92％, averaging 5.35％; K2O+Na2O 7.75％～11.55％, averaging 9.08％; K2O/Na2O 0.65～4.00, averaging 1.49; and MgO 0.40％～4.59％, averaging 1.11％. The R1-R2 diagram suggests that the porphyritic magma was formed during the late orogeny and the s yn-collision. Geochemically, the porphyry is relatively depleted in such HFSE as Nb, Ta, Ti and rich in Sr(337×10-6～718×10-6), with Y being 6.2×10-6～15.8×10-6 (≤18×10-6) and Yb being 0.20×10-6～1.63×10-6 (≤1.9×10-6). The REE have experienced strong differentiation and are thus markedly enriched in LREE. LREE/HREE ratios vary from 8.02～24.01, Sr/Y from 40.5～57.4, averaging 48.2(＞40 ), La/Yb from 17.5to 105.8, averaging 43.4(＞20), Sc from 2.5×10-6 to 2.5×10-6 (＜10×10-6), andδEu from 0.81 to 1.38. All these data indicate that the alkali-rich porphyry is geochemically characterized by adakite and belongs to C-type potassic adakite. The Machangjing porphyry is a kind of adakite and geochemically and envoirnmentally similar to the Yulong porphyry within the same ore-forming belt, which is somewhat of significance to geological prospecting.

Abstract:Iron oxide coated sand (IOCS) was prepared in laboratory. The effects of different parameters such as aqua pH, solidification temperature and iron solution concentration on characteristics of the IOCS surface were studied, and the wearing resistance of the coating-layer was estimated by abrasion experiments. SEM reveals that such factors as the oxide layer covering sand 30～60 in thickness, solidification temperature and iron solution concentration can obviously affect the shape, component and surface potential of IOCS. Abrasion test, with intensity about G=400～600s-1, shows that coating-layer mass loss increases under the higher G value, but with the increasing wearing cycle, the coating-layer wearing mass loss gradually decreases, and the quality of the coating layer tends to become stable.

Abstract:In this paper the authors studied the sorption of heavy metal ions Pb2+, Cu2+, Cd2+ on goethite as a case study of the mineral-water interface reaction. The prerequisite for the multi-reaction of heavy metal ions distributed on the mineral-water interface mainly depends on the hydrolyzation of the ad sorbates and the electric charge of the sorbent. Thus the pH value becomes a key factor affecting the reaction of mineral-water interface. Under different pH conditions, the electric charges of the mineral surface varied when the ≡FeOH protonated or deprotonated and meanwhile, the metallic hydrolysis could greatly develop t he formation of metal hydroxocomplexes and change the mineral-water interface re action. Under the condition of this study, metal affinity for the goethite surface was examined as a function of pH. Typical S-shaped adsorption edges could be observed for all metals; with the increasing pH, adsorption increased from zero to almost 100% over a narrow pH range. The metal capacity followed the trend of Cu＞Pb＞Cd. The heavy metal ions sorption isotherms could be fitted well by Langmuir and Freundlich equations with correlation coefficients R＞0.91. The constants of Freundlich equations (n values) are between 0.1 and 0.5, indicating that the surface complexes are very complicated but not monodentate. The change of constant KM also indicates the existence of a variety of surface complexes on goethite surface with the increasing of the pH value.

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2006年度正式发表的新矿物共17种. 其中硅酸盐8种，磷酸盐2种，砷酸盐2种 ，碳酸盐有1种，硫盐2种，硅化物1种，氯化物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