遵义附近岩石及其风化成壤过程中元素地球化学特征初探

本文利用一比五万遵义市幅、遵义县幅区域地质调查工作中岩石和土壤测量成果,较系统地论述全区各时代地层岩石元素背景含量、元素共生组合和富集成矿的特征,以及土壤剖面上元素含量变化规律等方面入手,对遵义地层岩石及其风化土壤中元素地球化学特征作一初步探讨,可供该区进行地质找矿、研究环境地球化学、探讨化探工作方法时参考。     

冲积平原区重金属元素异常解析中的矿物学方法

冲积平原区生态地球化学调查方法技术研究中矿物鉴定和化学分析结果对比研究表明，土壤中化学元素的含量及其分布特征主要取决于土壤对成壤母质中各种矿物成分的继承，元素的区域地球化学背景差异和在不同深度的含量变化均可通过矿物和矿物组合特征较为直接地示踪显现，土壤中矿物组成对其化学元素含量的影响是直接的、决定性的。因此，利用土壤的矿物组成确定其常量和微量元素的初始值具有重要意义。据此可进一步解析土壤中元素地球化学异常成因，判别土壤的元素地球化学异常类型。     

成都平原西部元素的分布特征及其研究意义

依据１：２０万都江堰幅区域化探资料,重点对都江堰市、彭州市、温江及大邑等县部分地区土壤中对人体、农作物有益、有害元素的分布及各农业地球化学区无限元素的分布特征进行了较为详细的阐述,并探讨了其在农业,环境及地质填图主面的研究价值。     

土壤表层与深层元素含量比值系数研究

通过研究元素含量在土壤表层和深层的比值,可以了解土壤表层元素含量的富集特征、成因和对环境的影响.将土壤中部分元素表层含量与深层含量进行了对比,统计、研究了比值系数及其分布特征,并对元素Cd区域性富集特征进行了探讨.指出成土母岩、元素化学特性、pH值、人类活动等对土壤中元素含量的富集具有重要的影响作用,应以地质、地球化学、人类活动等综合因素来研究土壤中元素含量的变化.     

内蒙古额济纳旗沙河北幅土壤地球化学特征与异常评价

通过内蒙古额济纳旗沙河北幅1∶5万区域地质调查、1∶5万土壤地球化学测量和1∶1万土壤地球化学剖面测量,结合区域地质特征,对区域土壤地球化学数据进行元素含量特征、单元素异常、元素组合异常的分析,根据异常检查和土壤地球化学剖面验证结果,发现了较好的土壤地球化学异常地段,并对该异常进行解释评价,从而圈定找矿靶区,并提出进一步工作的建议。     

华东多目标区域地球化学调查区土壤常量元素地球化学特征

为了研究土壤常量元素来源及分布特征,分析了华东多目标地球化学调查区表层土壤和深层土壤常量元素质量分数的关系,以及不同成土母质发育的土壤常量元素质量分数之间的相互关系。结果显示：在该地区表层土壤和深层土壤中,常量元素存在显著相关性,质量分数比值为0.75～1.04,说明该区域表层土壤常量元素与深层土壤属于同一物质来源,主要来源于成土母质;常量元素在不同地质单元区土壤质量分数的高低及变异系数的大小除了成土母质原因,元素自身地球化学性质也是其主要影响因素;元素之间相关性及因子分析很好地区分出了在该地区成土过程中元素共生组合特征,即CaO-MgO-Na₂O、Al₂O₃-TFe₂O₃-K₂O、SiO₂3个组合。通过分析可以得出在该地区表层土壤常量元素对成土母质有良好继承性,因此能够利用表层土壤元素组合特征和质量分数高低在一定程度上辨别该地区土壤的成土母质岩性、来源和土壤机械组成。     

土壤—作物系统中重金属元素的地球化学行为

对我国部分土壤和作物中重金属元素的分布特征作了概括性的论述，指出重金属元素的富集或贫化与成土母质、土壤环境等因素密切相关。母质母岩中元素含量高则相应土壤中该元素富集；土壤偏碱性或氧化条件下，重金属元素的有效性低；重金属元素通常富集于土壤表层0-20cm层位。不同种类的粮食、蔬菜对土壤中重金属元素具有不同程度的吸收和富集能力，叶类菜比茎类菜对重金属具有更强的吸收和富集能力，粮食作物的根比籽粒含重金属更多。对已污染的土壤大多采用生物修复和生态修复方法。     

湛江市菠萝主产区基岩-土壤-菠萝元素迁聚特征

为研究元素在基岩-土壤-作物系统的迁聚特征,选取湛江市徐闻县菠萝主产区为研究区,采集土壤和菠萝样品,结合元素迁移系数、生物富集系数评价了基岩-土壤-菠萝系统元素的分布和迁聚特征。结果表明: 研究区土壤含富磷(TP)、土壤全铁(TFe₂O₃)、Co、Ge、S、Se含量丰富,土壤全氮(TN)含量中等,有机质含量以中等—较丰富为主,土壤全钾(TK)含量缺乏。基岩风化成土过程中,土壤中Pb、Cr、TFe₂O₃、Ni相对基岩表现为富集,Al₂O₃、Cu、Zn、Co、Mn、TP、K₂O相对基岩表现为流失; 土壤中Co、Cr、Cu、Ge、Mn、Ni、Zn主要来源于磁铁矿风化蚀变,Se主要来源于黄铁矿风化蚀变。菠萝果实对Cd、Hg为微弱吸收,Cd相对其他元素更容易在菠萝果实中富集。Ge、As、Cd、Se、Ni在菠萝根部最为富集,Pb、Hg、Cr、Cu、Zn在菠萝叶片最为富集,菠萝果实对Cu、Pb、Cr、Hg的吸收存在协同作用。研究成果可为当地菠萝产业发展提供依据。     

江西信丰油山地区土壤硒及重金属元素地球化学特征

为研究江西信丰油山地区绿色富硒土壤的分布特征,进一步指导当地耕种,提高农作物质量,通过在油山地区采集1277件表层土壤样,选取典型土壤横向和纵向剖面,研究该区土壤Se及重金属元素的地球化学特征。油山地区绿色富硒土壤主要分布于西部震旦系;横向上,沿河水流动方向,土壤中的Se、As、Cr、Ni和Cu含量逐渐降低,Se与As、Cr、Ni、Cu呈显著正相关;垂向上,土壤中的Se与重金属元素在地表富集,Se仅与As呈显著正相关;土壤Se与重金属元素来源于震旦纪坝里组黑色碳质板岩,随水共同迁移,富集于母岩近区及河流汇集区。     

黔北白云岩红色风化壳元素地球化学特征

选取贵州高原喀斯特地区典型白云岩风化剖面作为研究对象,探讨了红土剖面元素迁移特征及其影响因素,为进一步认识红色风化壳元素地球化学特征提供依据。结果表明:（1）红土剖面中土壤样品（XPS-4~XPS-25）Fe、K、Mn常量元素及Co、Pb、Zn微量元素的分布曲线相对于其他元素靠近 UCC,元素Mg、Ca、Na、Ti和 Li、Cr、Ba、V 的数据点则显著偏离了上部陆壳的平均组成。（2）元素对协变分析得出Ti与Fe、Ba和V的积累特征一致,呈增加趋势;Ti与Mg呈反向变化特征。（3）以Ti为参比元素的剖面迁移特征表明,绝大部分元素的地球化学行为表现为迁移淋失,仅 Fe 、Cr和V 富集。K、Ba总体上呈迁出趋势,个别层段有轻微富集;Na和Co在风化原岩处有一个富集端点。元素在风化过程中的迁移聚集与土壤剖面的pH值和剖面结构变化、粘土矿物和有机质等的吸附有关。      

Seasonal changes in the soil moisture distribution around bare rock outcrops within a karst rocky desertification area (Fuyuan County,Yunnan Province,China)

The spatial and temporal soil moisture distribution is an important control on surface ecological processes in areas with rock outcrops resulting from karst rocky desertification (KRD). To explore the local effects of bare rocks within different seasons, soil moisture was measured in a KRD region (Fuyuan County, Yunnan Province, southwest China) at different depths and in different directions and distances from rock outcrops in both the dry and the wet seasons. The soil moisture north and east of the rocks was higher compared to the other directions and to the control plot. This effect is attributed to the shading by the rocks. The shading effect is evident in all seasons but more pronounced in the dry season. In the wet season, the directional dependency is restricted to the surface layer and the increase in soil moisture with depth is more pronounced around the rocks than at the control plot. This is attributed to precipitation-induced runoff from the rock outcrops infiltrating into the deeper layers at the rock–soil interface. These findings suggest the redistribution of water in the wet season and the spatial variation of evapotranspiration in the dry season are factors controlling the local soil moisture pattern around the rock outcrops.     

Selenium source in the selenosis area of the Daba region,South Qinling Mountain,China

Naore Village in the Shuang'an countryside, Ziyang County, Shaanxi Province is located in the Daba region of South Qinling Mountain. It is one of two selenosis or selenium poisoning areas in China. Crops grown in the area are enriched in selenium. The soil is derived from high-selenium, pyritic, black carbonaceous slate and volcanic tuff of the Lujiaping Formation, Early Cambrian and Late Neoproterozoic in age, which is exposed in this area. The Lujiaping Formation is more than 40-m thick. Selenium content of the volcanic tuff averages 32 mg/kg Se and the black carbonaceous slate averages 22 mg/kg Se, which represent the highest concentrations recorded among all the strata and rocks sampled in the Daba region of South Qinling Mountain. This series of selenium-enriched rocks is also found in other places in the Daba region, South Qinling Mountain, where the soil contains about 10 to 30 mg/kg Se. These zones are latent selenosis zones in the Daba region. In addition, a selenium-enriched black carbonaceous shale, of Early Cambrian age, and containing 10 to 40 mg/kg Se, occurs in several other provinces in the south of China.     

陇东地区水土流失与地质作用初步分析

陇东地区是黄河上游水土流失严重区 ,也是国家重点治理的地区之一。由于特殊的岩土体的存在 ,加重了这一地区水土流失作用的危害性。本文通过水土流失现象与地质作用的关系进行偿试性探讨 ,旨在从中找到防治水土流失的有效措施 ,开展治理工作     

四川万源地区硒的地球化学特征

利用针对万源地区不同类型岩石、土壤以及茶叶样品进行系统的硒元素含量分析,研究其在岩石、土壤及农作物中的地球化学特征,结果表明万源地区震旦系岩石的硒质量分数最富(0.548×10-6),其次是寒武系(0.274×10-6),最贫为志留系(0.044×10-6);而不同岩性中硒质量分数最高的是页岩(0.355×10-6),碳酸盐岩次之(0.113×10-6),砂岩中最少(0.088×10-6)。土壤中硒质量分数最高为大竹河地区(万源地区东北部,0.51×10-6),大部分片区高于(大竹河、青花0.39×10-6、旧院0.3×10-6等片区)或接近(草坝0.14×10-6、竹峪0.16×10-6等片区)全国土壤平均值(0.215×10-6),属中硒含量水准。对茶叶中硒质量分数的分析表明除草坝(0.068×10-6)、竹峪(0.052 8×10-6)较低,大竹河片区种植的茶叶(0.104 6×10-6)与陕西紫阳富硒茶叶(0.105 8×10-6)的含量水平相近,证实万源地区有发展特色富硒农产品的基础条件。     

土壤元素异常成因研究及生态风险评价

山区岩石与水系沉积物,对山前平原土壤物质组成具有控制作用。土壤地球化学调查,查明北京某地区土壤存在着大面积同心圆状的镉、铜、铅等多金属元素异常。研究表明,西北侧山区分布着种类繁多的岩浆岩、变质与沉积岩,但与山前土壤具有高度正相关的元素组合特征的主要是燕山期中酸性岩浆杂岩体,而且杂岩体周边及其下游的BY沟水系沉积物中的多金属元素也呈现出明显的高背景含量特征。同时,铅同位素组成亦指示山前平原土壤铅与山区岩浆岩铅、沉积岩铅具有一致的物质来源,从而证实山前土壤多金属元素异常主要来源于山区岩浆杂岩体。由于山前平原土壤呈现为碱性且农田仅种植旱地作物,故富含多金属的土壤对农作物生长的生态风险程度低下。     

Mineralogical and geochemical studies of boron-rich bauxite ore deposits in the Songqi region,SW Henan,China

The Songqi region, SW Henan, is an important bauxite province in China. The bauxite ore deposits occur unconformably on the top of Middle Ordovician argillaceous carbonates. The bauxite ores from the Songqi region are characterized by unusually high boron contents. In this paper, we report the mineralogical and chemical compositions of selected bauxite ores from the region. These new data, together with existing geochemical data of soils in the region, are used to evaluate the origin of boron enrichment in the bauxite ores. The compositional characteristics of tourmaline in the bauxite ores suggests that this mineral was likely derived from a meta-sedimentary protolith. Mass balance calculation reveals that tourmaline only accounts for a small portion of boron in the bauxite ores; the majority of boron in the ores must occur in other forms, possibly by ion absorption on the surfaces of diaspore and clay minerals. In the Songqi region, the Precambrian meta-sedimentary rocks are known to contain abundant tourmalines whereas the Cambrian–Ordovician argillaceous carbonates and the Upper Proterozoic shales are all enriched in boron in free ion state. We suggest that these rocks provided tourmaline and boron ion to the bauxite deposits in the region. Most known bauxite deposits in the Songqi region occur at the margins of boron-rich soil domains, suggesting that boron in soils is a potential exploration indicator for unknown bauxite deposits in this region.     

贵州从江那哥铜多金属矿床地一物．化特征与找矿前景

黔东南州从江县那哥铜多金属矿床位于江南造山带西南段,是该区代表性的多金属矿床。工业矿体呈层状、似层状赋存于青白口系甲路组（Qbj）和乌叶组（Qbw）的浅变质沉积岩中,受断层控制明显,产于F2断层破碎带内。区域构造岩浆活动频繁,基性一超基性和中一酸性岩浆广泛发育。那哥铜多金属矿床矿石硫化物的8^34scDT值介于-2．7％0～2．8％0之间,均值为0．1‰;黄铜矿8cuNBs6值变化范围为-（3．09％0～0．33％0;脉石矿物石英包裹体δDSMOW和δ^18H2O值范围,分别为J50．一44．和．～．,暗示该矿床成矿流体具有深源岩浆水和浅变质围岩变质水,O的混合特征,成矿流体7％中0的硫和4％铜0具7有9深％部0岩9浆0％来0源特征。地球物理电性测量结果显示,矿石和不同类型岩石间具有明显的电性（电阻率和视极化率）差异,并以此圈定多个异常靶区,显示本区具有良好的找矿前景。     

Environmental Geochemistry of Fluorine in the Rock—Soil—Water System in the Karst Region of Central Guizhou Province

Systematic determination of and adsorption experiment on fluorine in the carbonate rock-soil-water system in the karst region studied in Guzhou Province,in conjunction with the mineral surface and soil chemistry data,have revealed the geochemical characteristics of F and the mechanisms of its transport and entrichment in the rock-soil-water-system of the karst region central guizhou province,Deep-seated underground waters(-100m or lower)and soil layers in the karst region of central Guizhou are characterized by high-F anomalies whereas shallow-level underground and surface waters by low contents of F(mostly lower than 05mg/L).Fluorine in soil and water in the region studied comes largely from Triassic marine strata dominated by gypsum-bearing carbonate rocks.The special adsorption and desorption of F on the surface of geothite in soil layers are the important mechanisms of its transport and enrichment in the rock-soil-water system of the karst region studied.     

Behavior of mercury in the supergene zone of geothermal deposits,southern Kamchatka

Mercury distribution was determined in all types of solid materials from the supergene zone of geothermal deposits in southern Kamchatka: rocks, hydrothermally altered rocks (metasomatic rocks), soils, soil—pyroclastic cover, bottom sediments of perennial and intermittent streams, hydrothermal clays, artificial siliceous precipitates, and iron sulfides formed owing to thermal water discharge from a well. The mercury content varies from background values for the Kurile-Kamchatka region in fresh rocks to high and extremely high values in hydrothermal clays and monomineralic pyrite samples. The sources, migration conditions, and concentration mechanisms of mercury were evaluated. Mercury is supplied to the surface of geothermal deposits and thermal fields by a deep hydrothermal flow and is concentrated on thermodynamic barriers in hydrothermal clays, siliceous sinters (silica gel), and soils showing high salinity owing to the deposition in them of silica, sulfates, and other compounds from a vapor-water mixture. Newly formed clay minerals, iron sulfides (pyrite), silica gel, and biological materials (peat) can probably efficiently sorb mercury under geothermal conditions at atmospheric pressure and temperatures from 20°C to 120°C.     

湘西沃溪金锑钨矿床矿化蚀变带有机质特征初探

本文以矿床地质特征为基础,对赋矿围岩的有机质特征进行了初步探讨。在热液作用下,岩石中的Au⁺、Au³⁺等组分被有机质还原,有机质转变为二氧化碳。未蚀变岩石、钨矿化蚀变岩石和金锑矿化蚀变岩石的有机质热解色谱谱形、有机质热解参数、有机质成熟度等都有一定差别。未蚀变岩石的热解烃呈一次突发式释放,有机质的最高热解温度、产率指数、降解潜率和烃指数较低,有机质的成熟度最低(位于未成熟区)。钨矿化蚀变岩石的热解烃呈两次缓慢式释放,有机二氧化碳含量较高,有机质类型指数较低,有机质的成熟度较高(位于油区)。金锑矿化蚀变岩石的热解烃呈一次缓慢式释放,有机质的最高热解温度、可溶烃量、产率指数、有效碳、降解潜率和烃指数都较高,有机质成熟度最高(位于气区)。