Abstract:A total of nearly 100 m_thick picritic lava succession rarely seen in the world was recognized in the Middle Devonian Beitashan Formation on the southern margin of the Altay Mountains. Serpentinized euhedral-subhedral olivine phenocrystals are ominant in the picrites. Electron microproble analyses of the olivine phenocrysts reveal their homogeneous composition, with Fo contents ranging from 79.8% to 81.8% and CaO contents being extremely low (0～0.06%), much lower than their values in typical arc picrites. Based on previous experiments on Ca partitioning between olivine and silicate melt, it can be inferred that such low_Ca and low_Mg olivine crystals might have been generated by crystallization of high-Si, low_Fe and low alkali basalt.

Abstract:Located in the eastern part of the Baiyinwula-Dong Ujimqin Banner alkali granite belt on the southern edge of the Siberian plate, the Qagan Obo quartz diorite stock has an intimate temporal and spatial relationship with the Qagan Obo Fe-Zn deposit. SHRIMP magmatic zircon U-Pb dating of quartz diorite stock yields an age of 237±6 Ma (1σ), with the MSWD value being 0.63. Based on field geological investigation and laboratory data in combination with the result of zircon dating, it is suggested that the quartz diorite and its associated Fe-Zn ore bodies were formed in Indosinian period. Both of them were formed in a post-collision extensional tectonic setting within the Xing'anling-Mongolia orogenic belt.

Abstract:SR-XRF microprobe was used to measure elements in fluid inclusions hosted by quartz associated intimately with Cu mineralization of the Jiama and Nanmu deposits in the Gangdise copper-polymetallic metallogenic belt of Tibet. Analyses show that fluid inclusions from Jiama are rich in Cr and Pb but poor in Fe and Ni. In addition, fluid inclusions from Jiama show Pt and Ir anomalies, with the Pt and Ir concentrations higher than those of the continental crust. Fluid inclusions from Nanmu are rich in Cr, Cu and Pb but poor in Fe, Zn and Ni. In the Nanmu deposit, copper concentrations in highly saline fluid inclusions are by far higher than those in low salinity fluid inclusions and vapor inclusions, suggesting that copper selectively entered saline fluids. SR-XRF microanalysis also reveals that gold was concentrated in late-stage ore-forming fluids.Primitive mantle normalized patterns of the first transitional metal elements in fluid inclusions from Jiama and Nanmu are generally similar to those of mineralizing intrusives in the corresponding areas. These features imply that ore-forming fluids and ineralizing porphyries have similar material resources in Jiama and Nanmu districts. Both mantlederived and crust-derived materials contributed to mineralization. However, the ore-forming fluids did not originate from porphyries but evolved parallel to porphyries. SR-XRF microanalysis results of fluid inclusions fail to support submarine exhalation origin of the Jiama deposit.

Abstract:In view of low permeability of the reservoir and high freezing point of the crude oil, the authors conducted a comprehensive research on reservoir damage, which included petrologic-mineralogical characteristics, pore structure, fluid roperties, sensitivity and water-drive features by using experimental analysis and xploitation test. On such a basis, it is held that the main factors responsible for reservoir damage are as follows: separation of paraffin wax in the crude oil resulted in the falling of the stratigraphic permeability near the bottom of the oil well; the reservoir near to the water-injection well was damaged by bad water_injection quality; particle migration caused deep stratigraphic damage, bacterial plug and stratigraphic sensitivity damage and so on. Based on experimental data analysis, the authors have reached some conclusions and also put forward a few suggestions and schemes for improvement.

Abstract:In this paper, a set of pyroclastic rocks was discovered in the original Heilongjiang Group of Yilan area. They are composed of debris and fine-grained pyroclastics. The debris is in the lenticular and flame forms, whereas the fine-grained pyroclastics have been highly deformed. With similar composition, they are comprised of sodium amphibole, albite, epidote and minor amounts of chlorite; evertheless, there is an obvious difference between them in mineral content and mineral characteristics. Geochemical characteristics of pyroclastic rocks suggest that the debris belongs to alkaline basalt, with its LREE/HREE ratio between 3.87 and 4.24, its La/Yb)n between 7.20 and 8.12 , its Eu */Eu ratio between 1.03 and 1.09 and its REE distribution partition curve being of the right-oblique type. Compared to things of MORB, the trace elements of pyroclastics are more enriched in such incompatible elements as Sr, K, Rb and Ba. Yb is slightly lower than that in MORB. In the Zr-Zr/Y diagram and TiO-MnO×10[CD-P2O5×10 diagram, points of all samples are plotted in the oceanic-island basalt and interpolated area. It is considered that pyroclastics are alkaline basalts formed in an ocean island environment within the oceanic plate. Before the complete coagulation of these oceanic-island alkaline the hotspot in the oceanic plate became active again and broke the previously-formed alkaline basalts intoplastic-semiplastic debris, which was then cemented by pyroclastics. The pyroclastics are ocean island type pepyroclastics formed by “off-axis volcanism" within the oceanic plate. This discovery has provided some new clues to the paleotectonic environment and to the determination of tectonic attributes of the original Heilongjiang Group

Abstract:As natural rutile and Thiobacillus ferrooxidans (T.f) are distributed widely in nature, they may contact with each other in some cases and cause energy exchange. The authors explored the probability of the utilization of photo-induced electrons from natural rutile by T.f and the mechanism of this process. In the experiment, natural rutile could reduce Fe3+ toFe2+ under sunlight, the reduction rate reached 101.8 mg/L·24 h-1, and T.f obtained energy by oxidizing Fe2+ to Fe3+. Based on this experiment, the authors designed a device than could capture photo-induced electrons and pass them to bacteria via Fe2+ /Fe3+ mediator. In this way, T.f could utilize energy derived from photo-electron transition. In 96 hours, the strain under photocatalysis reached a density that was 100 times higher than that of the sample without experiencing photocatalysis. These results show that photocatalysis can give energy to bacteria and accelerate its growth.

Abstract:This paper studied the absorption of three kinds of heavy metal ions (Cu2+, Cd2+, Cr3+) on montmorillonite/humic acid complexes. The result shows that the montmorillonite absorbed humic acid can improve the absorption capacity of three heavy metal ions, and the improvement is increasingly remarkable with the rising concentration of absorbed humic acid. The Langmuir consants of adsorption isotherm can reach over 0.99. The adsorption amount of the three kinds of heavy metal ions increases with the rise of pH, but the adsorption amount decreases with ionic strength. Based on an investigation into kinetic characteristics of the three kinds of heavy metal ions on montmorillonite/humic acid complexes, the authors have found that the Elovicb equation and the two constant equation can describe the kinetic characteristics very well.

Abstract:In order to improve the soil in Hobq desert, this paper has dealt with such characteristics of palygorskite clays as gelatination, water absorbency and water conservation. Using local palygorskite_bearing clays from the Balagong mine, the authors conducted experiments on the formation of colloids, and the results show that the better ways seems to be ball-milling and colloid_milling under the onstant condition that the ratio of poly-acrylic acid sodium (PAAS) to water is 0.05 mL/100 mL. In this way, the ratio of soil to water reaches 20～21 g/100 mL, which is igher than that of rod_milling (18 g/100 mL) or churning up (6 g/100 mL). This study has provided a practicable method for desert control and opened up a new vista for the application of barren palygorskite clays.

Abstract:Due to its toxicity and extensive application, arsenide has already caused serious pollution to the environment, especially to the aqueous environment. Being economical, effective and free from secondary pollution, environmental mineral materials have increasingly shown their superiority in the treatment of water subjected to heavy metal contamination. In this paper, the advances made in the treatment of arsenic pollution by environmental mineral materials are reviewed.

Abstract:As an important group of minerals, sulfides, formed by the combination of one or more metals with sulfur, have great economic importance as a major source of most metals, and the research on sulfur isotope fractionations in sulfides constitutes a focus of discussion in the stable isotope geochemical field. Being an important geochemical tracer, the sulfur isotope fractionation in sulfides can be used to analyze the ore-forming process and the ore-forming material source. Based on the authors' up-to-date research, this paper dealt with the theoretical calculation of sulfur isotope fractionation in sulfides and has reached the conclusion that at present the improved method can be used to approximately calculate the thermodynamic isotope fractionation factors of sulfur in sulfides of geochemical interest.