云南东川因民铜矿金矿化特征及成因初探

因民铜矿发育两种金矿化类型:一是铜矿的伴生金;二是热液构造蚀变岩型。化探样品分析结果显示,金矿化主要赋存于金箔箐断层上、下盘的角砾状蚀变岩内,空间上受岩性和断裂构造的双重控制。邻区拖布卡金矿的成矿地质背景与本区相似,在成矿地质年代上作以类比推测,认为喜马拉雅期是主成矿期。另外通过对光片镜下和化探原生晕样聚类分析研究,发现构造蚀变岩型金矿化具明显的多期多阶段性及热液特征。     

准噶尔盆地中部III 区块原油中25-降藿烷分布特征与成因意义

通过对准噶尔盆地中部Ш区块原油或油砂抽提物的饱和烃气相色谱-质谱分析,研究了原油或油砂抽提物中25-降藿烷的分布规律.结果表明,不同井区或同一口井不同深度(层位)的原油25-降藿烷的相对含量存在比较明显的差别,表明其所遭受的生物降解程度有所差异,沿构造带从南到北,同一油层中原油的生物降解程度增强,比如位于构造北部(构造部位相对较高)的永1井、永3井侏罗系原油25-降藿烷丰度较高,表明生物降解比较明显,而位于南部(构造低部位)的永6井白垩系和侏罗系油层中的原油均无明显的生物降解现象;同一口井随深度增大生物降解作用将弱,如永2井浅部白垩系油层的原油降解较严重,而深部西山窑组的原油降解作用则不明显.根据原油生物降解的特征,结合车-莫古隆起调整对研究区油气成藏的影响,讨论了原油生物降解差异分布的成因机制.     

淮南煤田同变质程度不同煤层煤的成烃作用和储气性研究

本文从煤岩学、有机地球化学及煤的储气性原理出发,研究了淮南煤田同变质程度不同煤层煤(B_11b、B₁₀)在成烃母质、富烃特征、成烃作用和储气性等方面的差异性。B_11b煤层中含有较多的似石油物质、渗出体、显微组分等的荧光浸渍现象、油滴和油膜、微粒体等,它们是煤成烃作用的直接光学标志。B_11b煤层的地化参数指出较强的还原环境将有利于成烃作用。B_11b煤层的孔隙性（孔容、孔径分布、孔隙结构）说明它不仅有较好的储气性能,而且还具有较有利于煤层气体运移的物性条件。而上述特征是B₁₀煤层所不具备的。     

Geochemistry of porewater and sulfate-reducing bacteria in sediment cores from the Chianan Plain, Taiwan

High concentrations of arsenic and humic substances in groundwater from the southwestern coastal plain of Taiwan were well known for their probable relationships with black-foot disease. In order to realize the relationships between the concentrations of humic substances and arsenic in this area, 24 well water samples were analyzed. After filtered through 0.45 μm glass fiber membrane in the field, samples were kept in the dark at 4℃ and then separated into six fractions with varying range of molecular weight （〈0.5, 0.5-1, 1-5, 5-10, 10-50 and 〉50 k Da） by ultrafiltration apparatus （Molecular/Por Stirred Cell system） in the lab. Concentrations of humic substances were measured by fluorescence spectrometer （HITACHI F-2000, ex=370, em=445） and arsenic by FIAS-AA （Perkin Elmer AAnalyst 100, FIAS-400）. On average, only 6.2% of the total arsenic in water existed in the fraction of 〉0.5 k Da. and the others were complexed with humic substances （including humic acid and fulvic acid）. The results demonstrated a distinct positive correlation between the concentrations of humic substances and arsenic.     

Selenium contamination in the Colorado River Basin, western USA： Remediation by leaching and nanof＇dtration membranes

Selenium （Se） is an essential micronutrient to biota, but can become a potent toxicant at elevated concentrations. The natural sources and chemical properties of Se species make the boundary between deficiency and toxicity narrow for some biota, with both phenomena common around the globe. Large areas of farmland in the Colorado River Basin （CRB） generate salinized drainage water with Se concentrations much higher than 5 μg/L, the U.S. Environmental Protection Agency chronic water-quality criterion for the protection of aquatic life. We have carried out detailed field and laboratory studies to investigate Se geochemistry and remediation in two of these areas： the Middle Green River Basin, Utah and the Salton Sea Basin, California, located respectively in the Upper and Lower CRB. Results from these and other studies show that approximately 90% of the dissolved Se in the Colorado River and its tributaries originally is derived from the Upper Cretaceous Mancos Shale and equivalent pyritic marine units that outcrop in the Upper CRB. Selenium is mobilized commonly by biogeochemical oxidation of this pyritic shale and is concentrated mainly as selenate （SeO4^2-） in soils and agricultural drainage water of dry climates by evaporation. Minor （0%-5%） amounts of Se are present as the selenite species （HSeO3^-） and （SEO3^2-）, but these species and the more reduced species, elemental Se （SeO） and selenide （Se^2-）, have much lower solubility and/or have high sorptive affinity towards organic matter, clay minerals and iron oxyhydroxides. The concentration of dissolved Se （-2.5 μg/L） and salinity in the Lower Colorado River water are among the highest of the world major rivers. Because of low precipitation （7 cm/a） and extreme evapotranspiration （-1.8 m/a） rates in the Salton Sea Basin, California, Se values in irrigation water imported from the Colorado River increase to 〉300 μg/L in drainage wastewater. Removal of Se from contaminated wastewater by nanofiltration membranes was demonstrated in laboratory and pilot-scale field experiments.     

High resolution profiles of trace metals in pore waters of marine and riverine sediments assessed by DET and DGT

In polluted aquatic systems, toxic metals are often accumulated in bottom sediments. They are, however, not necessarily stored definitively because diagenetic processs can modify redox, pH and even the amount of complexing ligands, releasing the trace metals back into the pore waters and the water column. Especially the labile metal fraction in the pore waters is important since this is the bioavailable fraction determining the bio-toxicity of the sediments. The goal of our study was therefore to assess, with novel sampling techniques, this bioavailable metal fraction in the pore waters as well as the flux towards the overlying water column. High-resolution profiles of trace metals in pore waters of marine and riverine sediments were assessed by DET （diffusive equilibrium in thin films） and DGT （diffusive gradients in thin films） gel techniques. The DET technique uses a diffusive gel layer that equilibrates with the aquatic system and with this technique the concentrations of total dissolved trace metals are obtained directly. The DGT technique uses an acrylamide diffusive gel backed by a resin gel （Chelex） which binds trace metals. With the DGT technique only labile species of selected metals can be captured. According to the redox potential measurements, the marine sediments were suboxic （200 mV to -220 mV versus Ag/AgCl electrode）, while the riverine sediments were completely anoxic （-160 mV to -220 mV versus Ag/AgCl electrode）. This redox potential was apparently controlling the trace metals species in the pore waters： for example a strong correlation between Mn and Co was found in the riverine sediments （for DET and DGT sampling）, while in the marine sediments trace metals presented various behaviors.     

角度格式转换过程中可靠算法研究

提出了一种可靠算法是将原始度.分秒加上一个与之同符号,且不影响计算精度的有效微小量ｅ,然后再进行格式转换,能有效减少工程返工和损失。     

黄骅坳陷扣村地区古近系沙三段高分辨层序地层分析

通过利用钻井、测井、地震等多种资料，以黄骅坳陷扣村地区古近系沙三段为例，详细论述了开展高分辨层序地层分析的研究流程、方法．在四级层序格架确定的基础上，叙述了以一般湖泛面和更小级别的岩性和结构层序单元界面的识别与类型的确定．指出通过露头、岩心、测井曲线和高分辨地震信息，可以确定短期旋回界面与超短期旋回界面．根据工区的特点选取主干剖面，建立高分辨率层序地层网络格架对比剖面，开展长、中、短期基准面旋回的分析、高分辨率层序地层的单砂体展布分析及其沉积微相研究．     

激光剥蚀等离子体质谱分析中激光剥蚀参数对信号响应的影响

探讨了激光剥蚀等离子体质谱固体微区分析中激光剥蚀参数对元素分析信号灵敏度及稳定性的影响。这些参数包括激光功率、脉冲频率、剥蚀孔经、散焦距离、剥蚀方式等。讨论了优化的激光剥蚀等离子体质谱信号采集及数据处理方式。在全质量范围内选用具有代表性的元素作为研究对象,建立了激光剥蚀的一般性特征规律和266nm紫外激光系统的最佳操作条件。在选定的激光剥蚀参数下,大多数被测元素的检出限为22.8~457ng/g,能够满足固体微区分析的要求。