环境同位素硫在大同南寒武-奥陶系地下水资源研究中的应用

对山西大同口泉沟南寒武-奥陶系碳酸盐岩地下水(岩溶水)资源的开发研究中,利用不同价态硫富集34S的不同以及硫同位素分馏,主要是硫酸盐和硫化物中δ34S(SO₄2-)、δ34S(HS-)的变化,分析了岩溶水的来源,区分出表征循环交替和补给条件的三种地下水类型和环境,识别出口泉南水文地质区内各个地下水子系统及其相互关系。对岩溶水开发中泉域划分问题,使用硫同位素之间的关系,并结合硫酸盐中氧同位素δ18O(SO₄2-)以及14C关系,表明本区与相邻的两泉域相互独立。岩溶水中δ34S(SO₄2-)、δ34S(HS-)和δ18O(SO₄2-)有很大变幅,神头泉Z1岩溶水有罕见的异常值。     

口泉沟南水文地质区地下水补、迳、排条件及综合利用分析

分析了口泉沟南水文地质区地下水补、迳、排条件,提出了水资源综合利用措施：建设淤地坝利用地下水,建设一定数量的渗井利用洪水补给地下水。     

环境同位素方法在平凉市岩溶地下水研究中的应用

应用环境同位素方法对平凉隐伏岩溶水的研究结果表明 ,研究区隐伏岩溶水形成较早 ,且有大量现代水的混入 ,平均混入量为 5 4 %。说明研究区隐伏岩溶水的补给和更新能力较好。环境同位素分析结果还显示 ,大岔河隐伏岩溶水为一相对独立、半开放的水文地质单元。其补给来源部分为流域内大气降水、地表水的补给 ,部分为东南部三道沟岩溶地下水的补给。根据环境同位素 EPM与 EM两种模型计算 ,地下水的滞留时间为 36 a。地下水储存量为 1.314× 10 8m3;储水系数为 7.2 9× 10 - 3。这一结果与传统勘探方法的计算结果基本吻合 ,说明环境同位素方法的实用性 ,可在地下水资源调查中作为传统方法的补充和对比。     

渭北东部奥陶系岩溶地下水环境同位素特征分

本文通过对渭北东部岩溶地下水环境同位素组成特征的研究，分析了大气降水、地表水、地下水三者之间的转化关系，并对研究区岩溶地下水的形成进行了初步探讨，认为大气降水是研究区岩溶地下水的补给源，地表水与地下水之间存在水力联系，地表水对地下水的补给占补给水源的74.3％。西部岩溶裸露区为岩溶水的直接补给区，其周边浅埋区为岩溶水的间接补给区，东南部的岩溶中-深埋区为岩溶水的径流排泄区。     

平凉大岔河隐伏岩溶水补给的环境同位素研究

在干旱、半干旱的隐伏岩溶区进行地下水资源评价中，地下水的形成及补给是最基础，也是最棘手的工作。本文应用环境同位素技术对研究区隐伏岩溶水的来源、补给做了研究。结果表明，区内不同时代的岩溶水均由大气降水组成。隐伏岩溶水的补给局限在大岔河流域内，并有大量现代降水的混入，混入量平均为54％，说明该区隐伏岩溶水汇水条件良好，具有可观的开发利用价值。     

桂林地区岩溶水同位素水文地球化学研究

1984年在桂林地区不同类型岩溶水中取了61个氢氧同位素样品,根据分析数据结合水文地质条件论述了不同岩溶水的同位素组成及其影响因素,取得了如下认识:不同类型岩溶水在δD-δ~(18)O图上的分布具有一定的规律性,反映其补给源及形成过程的差异;同一类型水由于地质环境及补给源不同其δ值有显著差别,岩溶水同位素组成雨量效应掩盖了温度效应;本区岩溶水的同位素组成具有经受了不平衡蒸发的特点。     

渭北东部奥陶系岩溶地下水环境同位素特征分析

本文通过对渭北东部岩溶地下水环境同位素组成特征的研究,分析了大气降水、地表水、地下水三者之间的转化关系,并对研究区岩溶地下水的形成进行了初步探讨,认为大气降水是研究区岩溶地下水的补给源,地表水与地下水之间存在水力联系,地表水对地下水的补给占补给水源的74.3%.西部岩溶裸露区为岩溶水的直接补给区,其周边浅埋区为岩溶水的间接补给区,东南部的岩溶中-深埋区为岩溶水的径流排泄区.     

川滇高原斜坡地带峡谷区岩溶水化学特征及演化规律

岩溶地下水不仅作为重要的生活和生产用水水源,而且作为一种重要的地质营力,对于岩溶演化史具有重要影响,对其进行水化学特征分析及演化规律研究,能够为岩溶水资源及岩溶生态环境保护提供科学依据。以川滇高原斜坡地带峡谷区岩溶地下水为研究对象,结合研究区水文地质条件,对比分析了龙爪坝河岩溶水系统和洛泽河岩溶水系统内地下水化学特征。通过常规地下水化学组分、氢氧同位素分析和水文地球化学反向模拟,识别了地下水化学类型,确定了岩溶水的主要离子来源和补给特征,判别了发生的水岩相互作用过程。研究表明：岩溶地下水以大气降水为补给来源,离子源于岩石风化作用,物质来源为灰岩、白云岩夹灰岩,水岩相互作用均受方解石、白云石和石膏沉淀及溶解作用控制,且龙爪坝河岩溶水系统内矿物饱和指数趋近饱和,岩溶发育趋于停滞,而洛泽河岩溶水系统内矿物饱和指数处于不饱和或饱和的波动态,岩溶仍然发育。     

环境同位素在北京平谷盆地山前侧向补给研究中的应用

利用地下水水化学和同位素测试分析成果,结合区域地质、水文地质条件研究了平谷北山山区侧向补给情况和中桥水源地地区第四系松散孔隙水和下伏岩溶水关系。结果表明：研究区第四系松散孔隙水和基岩岩溶地下水均来源于大气降水,地下水化学类型均为HCO-3-Ca2+?Mg2+ 型;平谷北山山前基岩岩溶水侧向补给平原区第四系松散孔隙水和下伏岩溶地下水;通过D值估算得到中桥水源地第四系浅层地下水的山区岩溶水侧向补给和垂向降水入渗补给比例为57：43;中桥水源地基岩岩溶水接受山区岩溶水侧向补给和第四系孔隙水垂向越流补给比例为87：13。研究成果为平谷地区地下水资源量评价和地下水动力场数值模型的建设提供了关键参数,为区域地下水的合理开采和有序回补涵养提供了科学依据。     

云南维西县仙人洞泉和龙滩泉成因分析

主要根据仙人洞泉和龙滩泉的地质和水文地质调查资料,分析了研究区内岩溶发育特征,并应用水化学分析和同位素测试方法,研究分析了仙人洞泉和龙滩泉形成原因。认为研究区仙人洞泉和龙滩泉水化学及同位素特征相似,二者与金沙江水水化学组成差异较大,二者均以分水岭附近的石炭系地层为主要补给区,但仙人洞泉还接受更远地段地下水的补给,地下水沿岩溶裂隙和管道系统径流。     

高压微波消解法测定醋酸纤维过滤器采集的微尘粒子中的砷镉钴铬铜铁锰镍铅钒锌

最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提     

Analysis of F, Al, Mn, Zn, Fe, Cu, Ca and Mg concentrations in brick teas from main producing areas in China

Brick-tea-type fluorosis is a peculiar endemic disease in China, which had been discovered in minority areas of western China since 1980, and distributed mainly in Tibet, Inner Mongolia, Gansu, Xinjiang, Qinghai and parts of Sichuan Province. The prevalence rate of fluorosis in Tibetan and Mongolian nationality people was higher. Epidemiological investigation showed that fluorosis morbidity and degrees were different in different brick-tea drinking areas, and it was probably caused by drinking various kinds of brick tea from different regions. Therefore, we collected 33 samples of brick tea from six provinces where minority nationalities were accustomed to drinking a large quantity of brick tea. F concentrations were determined by the combustion hydrolysis-ion selective electrode method. The results showed that among the brick teas, the F concentrations ranged from the minimum 74.1 mg/kg in Yunnan Province to the maximum 991.2 mg/kg in Sichuan Province. Besides, there was a great difference among the various kinds of brick tea, and F concentrations decreased in the order of Kang brick tea, Green brick tea, Black brick tea, Mi brick tea, Fu brick tea, Chitsu ping tea, Puerh tea, and Tuo tea. The average F concentration in brick teas was 431.92 mg/kg.     

Shock-induced amorphous textures in plagioclase,Manicouagan, Quebec,Canada

The textural relationships and structural states of optically isotropic labradorite from the Manicouagan, Quebec, impact structure have been examined by light (optical) and transmission electron (TEM) microscopy. Two distinct diaplectic glasses have been recognized based on their contrasting morphology, timing and the inferred modes of formation. The earliest isotropic bands and grain-scale isotropism (maskelynite) optically exhibit a gradational,in situ transformation from crystalline plagioclase with preservation of relict textures (twins, grain boundaries). The same transformation from crystalline to amorphous structure is observed in TEM to occur heterogeneously at scales on the order of the unit cell. The progressive transformation of optical properties reflects an increase in the volume fraction and eventual coalescence of these amorphous units. This maskelynite-type diaplectic glass is interpreted to form in the solid-state directly from crystalline material during the compressional phase of the shock wave. The other isotropic material occurs in spatially discrete tensiongashes and planar deformation features (PDFs) that overprint the maskelynite-type glass. This second type of diaplectic glass (PDF-type) is developed homogeneously within a given glass band and exhibits sharp crystal-glass boundaries, in contrast to the gradational boundaries of the maskelynite-type glass. PDF-type glass is interpreted to form by melting in tensional release zones during passage of the rarefaction wave. These observations emphasize the ability of naturally shocked rocks to preserve subtle evidence of variations in the shock process from highly transient events.     

A catastrophic rockslide-debris flow in Wulong, Chongqing, China in 2009: background, characterization, and causes

On June 5, 2009, a catastrophic rockslide-debris flow occurred at the crest of the Jiweishan Mountain in Wulong, Chongqing, China. Approximately five million cubic meters of limestone blocks slid along a weak interlayer of bituminous and carbonaceous shale. The source mass descended from the upper part of the slope rapidly, crossing a 200-m wide and 50-m deep creek in front of it. Blocked by the opposite steep creek wall, the sliding mass changed its direction and traveled a further 2.2 km along the creek in debris-flow mode, finally forming a large accumulation zone with an average depth of 30 m. This is one of the most catastrophic rockslide events in recent years in China. It buried 12 houses and the entrance of an iron mining tunnel where some 27 miners were working inside. Ten people died, 64 missing, and eight wounded. Immediately after this disaster happened, the government organized an expert team to assist the rescue work. As one of the geological experts, the author did a lot of field investigations and collected first-hand information. Multi-methods including the remote sensing, 3D laser scanning, geophysical exploration, and numerical modeling were used for analyzing the characteristics and the triggering mechanism of the Wulong rockslide. The preliminary investigation results reveal that this rockslide with poor geological conditions was mainly induced by the gravitation and the karst effect and also affected by the previous mining activities. The research in this paper is meaningful and useful for further research on such kind of rockslides that are geologically similar to the Wulong rockslide.     

丘北普者黑岩溶地貌景观特征

通过介绍普者黑地区的岩溶地貌特征,借鉴石林和桂林的研究模式,对普者黑的岩溶地貌形成机理进行了深入研究,并针对普者黑独特的亚热带高原岩溶地貌的特征,阐述了其研究的科学价值。     

夏季长江河口潮间带反硝化作用和N2O的排放与吸收

采用培养箱乙炔抑制和现场静态箱法,于夏季(7月)在长江河口潮滩潮间带进行了采样,研究表明,长江河口潮滩水体自身N2O产生速率很低,在潮汐淹没期沉积物是上覆水体N2O的来源,其来自沉积物中反硝化、硝化等氮素循环的多个反应过程,沉积物中N2O自然产生速率在0.10～8.50μmol/(m2·h)之间,反硝化速率在21.91～35.87μmol/(m2·h)之间。退潮出露期中潮滩是大气N2O的排放源犤交换速率在-11.03～13.17μmol/(m2·h)之间犦,5～10cm地温是影响N2O排放速率的显著性因素;低潮滩-大气界面N2O排放、吸收速率在-5.75～0.49μmol/(m2·h)之间。总体上看,中潮滩是大气N2O的排放源;而低潮滩对大气N2O有明显的吸收作用。潮滩植被(海三棱草和底栖藻类)的光合作用明显抑制了N2O的排放并可能导致吸收,而其呼吸作用则增加了N2O的排放,潮间带-大气界面N2O的排放和吸收与CO2的排放、吸收有显著的正相关关系。     

Wavelength-dispersive X-ray fluorescence spectrometric determination of Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites

Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.     

日本北海道音调津的球状石墨

本文利用光学显微镜、X射线衍射仪、透射电镜等手段对日本北海道音调津球状石墨的成因、结构等进行研究,认为日本北海道音调津球状石墨中除了石墨外,还存在镍黄铁矿﹑黄铜矿﹑磁黄铁矿等金属硫化物矿物。通过透射电子显微镜观察发现音调津石墨中大部分是椭圆状石墨颗粒,高分辨晶格条纹主要是非晶态结构,但是同时也发现了结晶良好的石墨。高结晶度石墨的存在可能是在硫化物Fe-Ni-Cu的触媒作用下形成的。天然球状石墨的微结构和性状研究对天然石墨的形成和开发应用有重要意义,对新型碳材料的制备技术有重要科学意义。     

Parents,permission, and possibility: Young women,college, and imagined futures in Gujarat,India

This article advances critical geographies of youth through examining the spatiality implicit in the imagined futures of young women in rural India. Geographers and other scholars of youth have begun to pay more attention to the interplay between young people’s past, present, and imagined futures. Within this emerging body of scholarship the role of the family and peer group in influencing young people’s orientations toward the future remain underexamined. Drawing on eleven months of ethnographic fieldwork, my research focuses on a first generation of college-going young women from socioeconomically marginalized backgrounds in India’s westernmost state of Gujarat. I draw on the “possible selves” theoretical construct in order to deploy a flexible conceptual framework that links imagined post-educational trajectories with motivation to act in the present. In tracing the physical movement of these young women as they navigate and complete college, my analysis highlights the ways in which particular kinds of spaces and spatial arrangements facilitate and limit intra- and inter-generational contact, and the extent to which this affects young women’s conceptions of the future. I conclude by considering the wider implications of my research for ongoing debates surrounding youth transitions, relational geographies of age, and education in the Global South.     

冀北张家口地区汉诺坝玄武岩中麻粒岩捕虏体的硫化物相

捕虏体麻粒岩是了解下地壳形成和演化的重要样品。汉诺坝新生代玄武岩中的二辉麻粒岩捕虏体样品中富含各种硫化物相,主要类型有:①孤立产出的球状出溶硫化物;②矿物颗粒之间或颗粒内的粗晶硫化物;③次生硫化物包裹体群;④裂隙充填硫化物。电子探针分析表明,硫化物的矿物成分均为贫镍磁黄铁矿,(Ni+Co+Cu)/Fe(原子比)远小于0.2;(Fe+Cu+Co+Ni)/S(原子比)比地幔岩的磁黄铁矿小,多小于0.875,反映了一种S过饱和环境。各种产状的磁黄铁矿中Au、Ag都有一定的含量,其平均值分别为0.19%～0.22%(Au)、0.01%～0.02%(Ag),反映下地壳的麻粒岩化与金矿化的成因联系。磁黄铁矿的Ni、Co、Cu含量与S正相关,说明微量重金属元素与S具有同源的关系,由于地幔去气伴随S而进入下地壳。