重庆吴家湾铝土矿矿床地质特征及控矿因素探讨

重庆吴家湾铝土矿产于中二叠统梁山组(P₂l)之下,呈假整合覆于中志留统韩家店组粉砂质页岩或中石炭统黄龙组灰岩之上。矿体产状与地层产状基本致,铝土矿呈土状、豆(鲕状)、致密块状、砾屑状。一水硬铝石为主要矿石矿物。控制铝土矿形成的主要因素为古环境、地形地貌、构造位置和地层。     

Ra’s Abdah of the north Eastern Desert of Egypt: the role of granitic dykes in the formation of radioactive mineralization,evidenced by zircon morphology and chemistry

Syenogranitic dykes in the north of Egypt’s Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphology within the syenogranitic dykes allows precise definition of sub-alkaline series granites and crystallized at mean temperature of about 637 °C. The growth pattern of the zircons suggest magmatic and hydrothermal origins of radioactive mineralization. Hydrothermal processes are responsible for the formation of significant zircon overgrowth; high U-zircon margins might have occurred contemporaneously with the emplacement of syenogranitic dykes which show anomalous uranium (eU) and thorium (eTh) contents of up to 1386 and 7330 ppm, respectively. Zircon chemistry revealed a relative increase of Hf consistent with decreasing Zr content, suggesting the replacement of Zr by Hf during hydrothermal activity. Visible uranium mineralization is present and recognized by the presence of uranophane and autunite.     

秦岭凤太矿集区铅锌金矿区域成矿规律研究

陕西秦岭凤太矿集区位于商丹缝合带和勉略缝合带之间,是著名的铅锌金多金属矿集区,区内发育海相沉积改造型铅锌矿和构造蚀变岩型金矿,成矿类型多样.在矿床地质特征、成矿地质条件、铅锌金矿时空分布规律、成矿流体来源研究分析的基础上,对凤太矿集区铅锌金矿成矿规律进行了剖析.认为凤太矿集区铅锌金矿床是多种成矿作用叠加改造形成的,早期...     

淮南矿区煤矸石的物质组成特征及资源化评价

本文利用各种测试方法,对淮南谢桥、新庄孜和张集煤矿采集的不同层位来源的240个煤矸石样品的化学成分、矿物成分和微量元素的进行测试与分析,得出了淮南矿区不同煤矿煤矸石的化学成分特征及其中微量元素的含量变化,评价了煤矸石中有害元素的环境影响作用。结合煤矸石基本特征,提出了合理的资源化利用途径,为煤矿开采过程的主要固体废物煤矸石综合利用和资源化、煤矿环境保护提供了参考资料。     

Geochemical processes controlling arsenic mobility in groundwater: A case study of arsenic mobilization and natural attenuation

The behavior of As in the subsurface environment was examined along a transect of groundwater monitoring wells at a Superfund site, where enhanced reductive dechlorination (ERD) is being used for the remediation of groundwater contaminated with chlorinated solvents. The transect was installed parallel to the groundwater flow direction through the treatment area. The ERD technology involves the injection of organic C (OC) to stimulate in situ microbial dechlorination processes. A secondary effect of the ERD treatment at this site, however, is the mobilization of As, as well as Fe and Mn. The concentrations of these elements are low in groundwater collected upgradient of the ERD treatment area, indicating that, in the absence of the injected OC, the As that occurs naturally in the sediment is relatively immobile. Batch experiments conducted using sediments from the site inoculated with an Fe(III)- and As(V)-reducing bacterium and amended with lactate resulted in mobilization of As, Fe and Mn, suggesting that As mobilization in the field is due to microbial processes.     

盆地模拟技术中的化学动力学生烃模型与应用

油气地表化探数据的失真(特别是数据中的高值失真点)直接影响到化探异常圈定。本文根据油气地表化探数据的分布特点，利用概率统计原理，提出一种适合油气化探资料前期处理的失真数据的概率判定方法和处理手段，在对实际资料的应用中，取得了良好的效果。     

Defining the range of ecological shelter zones in the shore zone of Three Gorges Reservoir,China

To maintaining a health ecological environment in Three Gorges Reservoir (TGR) area, ecological shelter zones (ESZ) need to be built in the TGR shore zone urgently. Based on the implication and function of ESZ, this study first analyzed the relationships amongst three subsystems of the TGR area, including the upstream production-living land, the downstream reservoir water body, and the ESZ. Then a simple and practical hydrological environment model for controlling the eutrophication of the TGR water body was constructed to determine ESZ range of TGR. Additionally, based on the pollutant degradation efficiency of ESZ and the assimilative capacity of reservoir water body, a raster reverse tracking method was proposed to determine the range of ESZ. Thirdly, take Yangdu town in Zhongxian county as a typical region, the ESZ range under three scenarios of different rainfall intensity, degradation efficiency and inflow water quality that corresponding to the three decisive factors of defining ESZ range were discussed. Finally, the statistical laws of the ESZ’s width at each boundary points were discussed to facilitate the ESZ construction projects, and selected standardized rate at 70, 90, and 99 % were labelled as “General”, “Good” and “Excellent” level to represent the performance of the width of the ESZ range. In conclusion, it suggest “Good” level width as basic width of ESZ, and additionally a special protection zone should be put on upstream environment for the extreme large width at the boundary points.     

山西地区的波速比（V_P/V_S）特征研究

利用山西台网的数字地震观测资料,采用单震多台和达法、多震多台联合测定法,对山西北部、中部和南部地区波速比进行分析研究,结果表明：在2010年1月24日的河津万荣4.8级地震、4月4日的大同4.5级地震和6月5日阳曲4.6级地震前均存在波速比下降现象,其中前2次地震发生在波速比下降过程中,第3次地震则发生在波速比异常恢复阶段。之后山西中部和北部的波速比处于低值,尤其是山西北部的波速比低值持续,说明山西省北部是比较危险的区域。     

Analysis of the contributions of topographic,soil, and vegetation features on the spatial distributions of surface soil moisture in a steep natural forested headwater catchment

Surface soil moisture has been extensively studied for various land uses and landforms. Although many studies have reported potential factors that control surface soil moisture over space or time, the findings have not always been consistent, indicating a need for identification of the main factors. This study focused on the static controls of topographic, soil, and vegetation features on surface soil moisture in a steep natural forested headwater catchment consisting of three hillslope units of a gully area, side slope, and valley‐head slope. Using a simple correlation analysis to investigate the effects of the static factors on surface soil moisture at depths of 0–20 cm at 470 points in 13 surveys, we addressed the characteristics of surface soil moisture and its main controlling factors. The results indicated that the mean of surface soil moisture was in the decreasing order of gully area > valley‐head slope > side slope. The relationship between the mean and standard deviation of surface soil moisture showed a convex‐upward shape in the headwater catchment, a negative curvilinear shape in the gully area, and positive curvilinear shapes at the side and valley‐head slopes. At the headwater catchment and valley‐head slope, positive contributions of soil porosity and negative contributions of slope gradient and saturated hydraulic conductivity were the main controlling factors of surface soil moisture under wetter conditions, whereas positive contributions of topographic wetness index and negative contributions of vegetation density were the main controlling factors of surface soil moisture under drier conditions. At the side slope underlain by fractured bedrocks, only saturated hydraulic conductivity and vegetation density were observed to be the controlling factors. Surface soil moisture in the gully area was mainly affected by runoff rather than were static features. Thus, using hillslope units is effective for approximately estimating the hydrological behaviours of surface moisture on a larger scale, whereas dependency between the main static factors and moisture conditions is helpful for estimating the spatial distributions of surface moisture on a smaller scale.     

Determination of arsenic(III) for the investigation of the microbial oxidation of arsenic(III) to arsenic(V)

Recent evaluations of acute and chronical toxicity of arsenic resulted in a reduction of the standard value for total arsenic from 40 μg/L to 10 μg/L in drinking water which will be valid in Germany after a transition period as from January 1996. Arsenic is well known as substance of deep groundwaters, mainly of geogenic origin and normally found as As(III) or As(V). As(V) is well removable by flocculation and filtration after adding iron salts. As(III), however, has to be oxidized first to As(V). Therefore, it is important for treatment techniques to be able to distinguish between As(III) and As(V). A modified determination of As(III) using flow injection analysis was installed and optimized in order to investigate whether As(III) may be oxidized to As(V) by bacteria in natural waters. The results showed that at 4°C, no As(III)-oxidation was observed within 14 days. At room temperature, however, in the bacteria-containing samples, an As(III)-oxidation was found starting after 3 to 7 days. After 14 days, no As(III) was left over. In contrast, in the sterile samples, no As(III)-oxidation could be observed within 14 days. These results demonstrated that microbial processes influence the oxidation of As(III) to As(V) in natural waters.