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The Kuimeishan tungsten deposit is located in the junction area of the eastern segment of the E-W-trending Nanling tectonic zone and southern segment of the NE-NNE trending Wuyishan tectonic zone. It is characterized by intergrowth of quartz vein-type wolframite and skarn-type scheelite in Dingnan county, south of Jiangxi province (Gannan). However, there is no accurate chronological evidence to confirm whether the metallogenesis occured in the Yanshanian period. The SHRIMP U-Pb age of zircons obtained from the metallogenic biotite granite is (157.7±2.7) Ma (n=11, MSWD=1.9), and the Re-Os isochron age of molybdenite from the ore-bearing quartz veins is (153.7±1.5) Ma (n=5, MSWD=0.16). The accurate metallogenic and diagenetic chronology results indicate that the Kuimeishan tungsten deposit was formed during the large-scale diagenesis and mineralization of tungsten ore in the Mesozoic period that occurred in South China. Based on the ‘five levels+basement’ prospecting model and the latest prospecting clues, it is possible that new ore bodies are amassed in the contact zone of deep rock body in Kuimeishan, which has great potential for prospecting. It is significant to the deep and periphery prospecting for tungsten as we proposed the possibility of skarn type tungsten which occurred nearby the deep and periphery part of quartz vein type tungsten in the Gannan region.

Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) is suited to analyze the abundances and spatial distributions of trace elements in sulfide. However, the spread use of the technology on micro area analysis has been hampered by the different characteristics of sulfides from silicates and oxides and the lack of sulfide reference material, especially PGE-bearing reference material. In this study, a PGE-bearing sulfide (SRMD-1) is synthesized by remelted nickel sulfide fire assay button in AN evacuated quartz tube. The examination by BSE imaging revealed that the nickel button SRMD-1 was completely of monosulfide composition. Homogeneity testing by LA-ICP-MS shows that the RSDs of elements, such as S, Ni, Cr, Co, Cu, Pb, Sb, Cd, Bi, are less than 10%. The data suggest the homogeneous distribution of these elements inside SRMD-1, but elements Mn, Zn, Sn, Tl are not as homogeneous with relatively larger RSDs. Elements Ag, Au and Pt are homogeneous inside SRMD-1, but RSDs of other noble metal elements are relatively larger according to low element content, instrument fluctuations or mass spectrometry interference. The homogeneity of the nickel button will be improved by increasing the content for the noble metal elements and lowering the quenching temperature for the molten samples. During the analysis of the nickel sulfide fire assay button, the spectral interferences in light PGEs (Ru, Rh and Pd) by argides is serious, and must be corrected, while the interferences to Os, Ir, Pt and Au can be ignored. Compared to the button which is not remelted, the homogeneity of the elements improved significantly. According to the work documented here, it is possible to synthesized PGE-bearing sulfide reference material for LA-ICP-MS by remelted nickel sulfide fire assay button.

In the recent decade, a series of new progress on geological exploration work have been achieved in China. There have new people-oriented trends in modern mineral geological work. The present geological work related to mineral resources is very different from the previous status. For example, local geological party becomes a national-wide and world-wide geological party, special kind of mineral resources extends to all kinds of mineral resources, and special profession of geology develops to no profession. The new trend of growing two markets (national market and international market) has been formed in utilizing two resources (domestic resources and foreign resources). It requires that the close relationship should be established for geological exploration and rock & mineral analysis. On the one hand, it is urgent that geologists should further understand the features of modern testing technology, and fully utilize the instruments and equipments. On the other hand, the laboratory also need to provide the technological support for the geological exploration, develop the new analytical methods, new techniques, new equipments, to meet the requirement of on-site analysis, quick speed analysis, low cost analysis, easy-operation analysis, full and comprehensive analysis, and rather than only receive samples and export simply analytical data. At the same time, the management department should give an important role for the combining geological exploration with geoanalysis in the whole process of making policy and planning project.

In Re-Os isotope chronology, the acetone extraction process is quicker and easier compared to the anion exchange method. The Re solution which was separated and purified by acetone extraction is suitable for the measurement by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), but unsuitable for Negative Thermal Ionization Mass Spectrometry (N-TIMS) directly because of high salt contents. An improvement was made to the acetone extraction method to separate and purify Re for N-TIMS determination by increasing the alkalinity concentration from 5 mol/L to 10 mol/L. Compared with the anion exchange method, the acetone extraction process is not only easier to operate with lower blank (Re 3-7 pg), but also saves time. The signal intensity of Re was over 100 mV per 1 ng Re, which met the requirements of a high-accuracy instrument measurement completely. The national first grade standard material of JDC (GBW 04436) and the laboratory reference material of JCBY were measured to verify the improved method. The Re contents of JDC and JCBY obtained from this method were (17.17±0.50) μg/g and (38.34±0.44) ng/g, respectively, which were consistent with the certified value of JDC (17.39±0.32) μg/g and the certified value of JCBY (38.61±0.86) ng/g. The improved procedure was applied to practical samples with good long-term results.

Scholars at home and abroad in recent years have focused on researching ammonia nitrogen pollution migration rules in the vadose zone soil. Column simulation and software simulation were primarily conducted for the study of ammonia nitrogen pollution migration. Biotechnology was widely used in degradation of pollutant in soil, but less applied to the study of pollution migration. This study applied Denaturing Gradient Gel Electrophoresis (DGGE) and the sequence analysis of the V3 Region of 16S rRNA combined with canonical correspondence analysis to characterize the bacteria vertical distribution characteristics and bacterial community structure in the soil from three typical contaminated zones in the North China Plain. According to the analysis of physical and chemical soil properties in polluted areas, there were some dominant individual bacteria in the key pathways of the nitrogen cycle and sulfate metabolism. It is suggested that the bacterial communities are affected by the distributions of ammonia, nitrate and nitrite nitrogen, showing that the community structure information of the dominant population in contaminated soil is an important parameter to study the ammonia nitrogen pollution migration rules.

Traditionally, the percentage sum method is used to check the data quality of total analysis of constituents for silicate rock. For samples with a high content of trace elements, the contents of major elements obtained by X-ray Fluorescence Spectrometry (XRF) will deviate from the true values, regardless of trace elements, as will its corresponding matrix effect to the major element. The method described in this paper improves the accuracy of major element content in silicate samples with a high content of Sr and Ba， through extending the calibration curve′s quantitative range of Sr and Ba by Chinese National Standard Materials and artificial standard materials, and applying a matrix correction coefficient of Sr and Ba to the major element calibration procedure. The validity of the method was substantiated by analyzing the national standard materials; the relative standard deviations (RSD) of major elements were less than 2%. Additionally, analysis results of major elements of national standard materials and artificial standard materials, which do not participate in regression were basically in accordance with reference contents. The method can be used to satisfy the analysis of silicate rock and the sum results of all major elements meet the standard of specification of testing quality management for geological laboratories (99.3% to 100.7%).

The accuracy and precision are lower, and the detection limit is higher for the determination of F with low content and low fluorescence yield by using X-ray Fluorescence Spectrometry combined with lower dilution ratio fused bead samples preparation. In this paper a method has been reported for the determination of 12 major, minor and trace elements in phosphate ores by wavelength dispersive X-ray Fluorescence Spectrometry. A lower-dilution ratio (5∶1 reagent to sample) fused bead sample preparation mix was used for measurements. Chinese National Standard Materials with similar matrix elemental compositions to the samples were used to calibrate the matrix effect with the experience coefficient method. Results show that precision and accuracy of the method are greatly improved for 12 components, with lower detection limits and satisfactory results for unknown samples. Especially, precision, accuracy and detection limit of F were better than the analytical results in literature and were obtained by using a 10∶1 fused dilution ratio. Meanwhile, this method solved the technological problem by determining the F component using a pressed pellet sample, and other major and minor components by using fused bead pellet samples. The detection limit of F was also lowered by using this method.