牙克石市翠干公路岭上铅锌钼多金属矿床地质特征简述

该矿床位于阿尔山—博克图—鄂伦春成矿带的中南部,产于晚侏罗世玛尼吐组之中,矿体受北西向次级构造控制,成因类型为斑岩型及破碎带蚀变岩型。     

地球化学方法在福安堡钨钼矿床的应用

吉林省中部大面积森林覆盖区,分布着大面积华力西期、印支期花岗岩类,受传统成矿理论的束缚,这一地区成为有色金属矿产勘查的"处女地".1∶20万化探扫面之后,相继开展了不同方法的地球化学异常查证工作,发现了很有前景的福安堡钨钼矿床.结果表明,在东北森林覆盖区化探找矿方法十分有效.     

地球化学方法在南祁连天峻县阳康曲一带找矿的应用

通过对南祁连天峻县阳康曲一带1∶20万水系沉积物ZHs-12号Au异常的查证,在该异常范围内圈出了AS22号1:5万Au异常,又对AS22号1:5万Au异常进行查证,采用1:1万土壤测量,又圈出了AP3、AP4两个土壤异常,在AP4号土壤异常中发现了多条金矿体,最终发现了青海省天峻县阳康曲陇王玛珠金、铁多金属矿,该矿床的发现表明了在该地区利用不同的地球化学方法进行找矿效果非常明显,对具有相类似的1:20万或1:5万水系沉积物异常进行查证,最终发现矿体,具有重要的指导意义。     

吉林省中部大中型钼矿发现过程中勘查地球化学方法的应用效果

从全国20世纪70年代末开展的新一轮化探找矿方法应用开始,在吉林省中部相继发现和评价了一批有价值的贵金属、有色金属矿床、矿(化)点。最为突出的是从1998年始至今,通过不懈地努力、探索、研究与实践,发现和评价(有的正在评价过程中)舒兰市福安堡、舒兰市季德屯、永吉县一心屯、磐石市后倒木、桦甸市四方甸子、永吉县芹菜沟等几处中型规模以上矿床。总结其矿床发现过程的经验与教训,研究其找矿方法的应用与效果,对指导今后的地质找矿、尤其勘查地球化学方法与地质找矿理论、方法的应用有着深远的意义。     

论地球化学在地质找矿中的重要性

本文分析了地球化学在地质勘查中的重要作用,包括提升找矿效果、强化找矿有效性,随后介绍了地质找矿中地球化学所获成就,包括地质找矿中地球化学作用地位、地球化学形成的三次大规模矿产开发,最后介绍了地球化学获得成功的原因,包括创建理论基础、标准物质研制和分析技术持续发展、地球化学海量数据支持,希望能给相关人士提供有效参考.     

深穿透地球化学在黔西北隐伏铅锌矿找矿中的应用

黔西北是川、滇、黔铅锌多金属成矿区的重要组成部分,区内矿床沿区域性断裂呈带状分布,矿体主要受断裂构造和岩性的双重控制,且多为高品位的隐伏矿。由于常规化探方法在寻找深部隐伏矿方面存在短板,本文在黔西北杉树林、洗线沟和青山铅锌矿床开展了深穿透地球化学勘查法(土壤吸附烃和地电提取法)的探索并取得了良好的找矿效果。研究发现,有机烃(甲烷、乙烷、丙烷、乙烯等)异常和地电提取离子(Pb、Zn、As、Sb和Hg)异常与深部隐伏铅锌矿体具有明显的对应关系,在青山矿床外围利用地电提取法成矿预测了深部隐伏矿体,有机烃异常也为杉树林矿床下一步找矿指明了方向。     

西安多目标地球化学调查在揭示隐伏断裂中的应用

多目标地球化学调查是一项基础性、公益性地质调查工作,西安地区多目标地球化学调查是西部开展此项工作较早的省份,也是黄土厚覆盖区开展此项工作的一个代表。本文简介了陕西省西安地区多目标地球化学调查工作的基本情况,并阐述了多目标地球化学调查成果在示踪隐伏断裂、追踪地裂缝带等方面的应用。     

北方干旱区水地球化学方法应用效果

北方干旱区由于雨水稀少，地下水多以井水（或泉水）的形式分布。取样宜于同一季节，以旱季最佳，该季节的地下水中元素含量相对较高。水中微量元素含量很低，多为10－9级，野外取水样时多采用元素预富集技术，如共沉淀技术和聚氨脂泡塑吸附技术等，分析测试主要采用光谱定量分析。水地球化学异常解释时必须紧密结合地质特征和水文地质条件，对异常作出正确解释和恰当评价。通过几个已知点试验研究，并扩大调查面积，对铜铅锌等有色金属矿、金银等贵金属矿、放射性铀矿以及地热等矿产资源，均取得了明显的应用效果，指出了试验区外围具有普查找矿价值的异常多处，特别在厚层疏松复盖层地区开展水地球化学调查应用效果尤为独特。水地球化学方法一般适用于区域普查阶段。     

模式识别在地球化学中的应用

地球化学数据模式识别技术，是通过模式识别数学处理方法，对地球化学异常进行多元素信息提取，确定不同地质体及不同类型成矿作用的元素异常特征和异常分带。提取各种不同类型及不同元素组合的成矿异常。     

地球化学勘查综合方法在潞西金矿找矿中的应用

地球化学勘查是找矿预测的重要手段,在云南潞西金矿的地质勘查工作中采用了多种地球化学勘查手段,包括X荧光、γ能谱、氡气测量及地电化学.X荧光测量能快速有效地对成矿有利地段的红色粘土层进行快速评价,圈定矿化带和红色粘土型金矿体;在有红色粘土型金矿矿化异常的地段,采用简便易行的γ能谱和氡气测量进行初查,再进一步开展地电化学勘查工作寻找卡林型原生金矿.多种方法综合运用,取得了良好的找矿效果.     

香炉碗子金矿区水文地球化学方法找金效果探讨

通过对金在地下水中的存在形式及其富集方法相关条件的研究,提出了水文地球化学找金的工作方法,经过对香炉碗子金矿地下水的采样分析及成果的综合研究,其结果与金矿分布规律基本吻合。同时对该方法在找矿中的效益与前景进行了分析。     

大兴安岭乌兰哈达地区铀矿找矿进展与找矿预测

内蒙古乌兰哈达地区位于大兴安岭林西-扎兰屯多金属成矿带上,属于扎兰屯火山岩型铀成矿远景带.通过1/5万伽玛能谱测量工作发现工区内古生代、中生代地层U背景值1.88×10-6~2.54×10-6,海西期花岗岩U背景值为3.74×10-6,具备很好的铀源条件.该区断裂构造及层间破碎带发育,为铀矿运移提供通道和沉淀的场所.粘土矿化、萤石化等热液蚀变发育,可以作为铀矿找矿的热液蚀变标志.通过放射性测量工作圈定9处铀异常区,发现2处铀矿化带,圈定了2个找矿靶区,为该地区铀矿找矿指明了方向.     

Isotope hydrogeochemical models for assessing the hydrological processes in a part of the largest continental flood basalts province of India

Continental Flood Basalts (CFB) occupy one fourth of the world’s land area. Hence, it is important to discern the hydrological processes in this complex hydrogeological setup for the sustainable water resources development. A model assisted isotope, geochemical, geospatial and geophysical study was conducted to understand the monsoonal characteristics, recharge processes, renewability and geochemical evolution in one of the largest continental flood basalt provinces of India. HYSPLIT modelling and stable isotopes were used to assess the monsoonal characteristics. Rayleigh distillation model were used to understand the climatic conditions at the time of groundwater recharge. Lumped parameter models (LPM) were employed to quantify the mean transit time (MTT) of groundwater. Statistical and geochemical models were adopted to understand the geochemical evolution along the groundwater flow path. A geophysical model was used to understand the geometry of the aquifer. The back trajectory analysis confirms the isotopic finding that precipitation in this region is caused by orographic uplifting of air masses originating from the Arabian Sea. Stable isotopic data of groundwater showed its meteoric origin and two recharge processes were discerned; (i) quick and direct recharge by precipitation through fractured and weathered basalt, (ii) low infiltration through the clayey black cotton soil and subjected to evaporation prior to the recharge. Tritium data showed that the groundwater is a renewable source and have shorter transit times (from present day to <30 years). The hydrogeochemical study indicated multiple sources/processes such as: the minerals dissolution, silicate weathering, ion exchange, anthropogenic influences etc. control the chemistry of the groundwater. Based on the geo-electrical resistivity survey, the potential zones (weathered and fractured) were delineated for the groundwater development. Thus, the study highlights the usefulness of model assisted isotopic hydrogeochemical techniques for understanding the recharge and geochemical processes in a basaltic aquifer system.     

Geochemistry and assessment of hydrogeochemical processes in groundwater in the southern part of Bathinda district of Punjab, northwest India

Hydrogeochemistry of groundwater is important for sustainable development and effective management of the groundwater resource. Fifty-six groundwater samples were collected from shallow tube wells of the intensively cultivated southern part of district Bathinda of Punjab, India, during pre- and post-monsoon seasons. Conventional graphical plots were used to define the geochemical evaluation of aquifer system based on the ionic constituents, water types, hydrochemical facies and factors controlling groundwater quality. Negative values of chloroalkaline indices suggest the prevalence of reverse ion exchange process irrespective of the seasons. A significant effect of monsoon is observed in terms chemical facies as a considerable amount of area with temporary hardness of Ca²⁺–Mg²⁺–HCO₃ ^? type in the pre-monsoon switched to Ca²⁺–Mg²⁺–Cl^? type (18%) followed by Na⁺–HCO₃ ^? type (14%) in the post-monsoon. Evaporation is the major geochemical process controlling the chemistry of groundwater process in pre-monsoon; however, in post-monsoon ion exchange reaction dominates over evaporation. Carbonate weathering is the major hydrogeochemical process operating in this part of the district, irrespective of the season. The abundance of Ca²⁺ + Mg²⁺ in groundwater of Bathinda can be attributed mainly to gypsum and carbonate weathering. Silicate weathering also occurs in a few samples in the post-monsoon in addition to the carbonate dissolution. Water chemistry is deteriorated by land-use activities, especially irrigation return flow and synthetic fertilisers (urea, gypsum, etc.) as indicted by concentrations of nitrate, sulphate and chlorides. Overall, results indicate that different natural hydrogeochemical processes such as simple dissolution, mixing, weathering of carbonate minerals locally known as ‘‘kankar’’ and silicate weathering are the key factors in both seasons.     

Early Pleistocene magmatism in the central part of the Greater Caucasus

An isotope-geochronological study of young magmatism in the central part of the Greater Caucasus (Kazbek neovolcanic area) on the territory of Russia and Georgia has been carried out. It was proved for the first time that, in the Early Pleistocene, there was a separate impulse of magmatic activity in this area. The area of endogenic activity for the period identified was contoured on the basis of the integrated isotope-geochronological, petrological-geochemical, and geological data. It has been shown that the Early Pleistocene volcanism inherits the area of Neogene volcanism in the Kazbek region and, therefore, presents the final impulse of the second (Pliocene) stage of the Late Cenozoic magmatism. Thus, Early Pleistocene volcanism was not a precursor of Late Quaternary magmatism as the latter has other spatial patterns of the location of volcanic centers.     

等值反磁通瞬变电磁法在公路隧道塌陷区的探测应用

某在建公路隧道开挖中发生塌陷,选用等值反磁通瞬变电磁法(OCTEM)进行抢险探测.文中介绍了OC-TEM方法原理,针对公路隧道地电结构建立模型,通过正演计算证明了OCTEM具有对地电阻率反映灵敏、分辨率高的特点;将该公路隧道的OCTEM探测结果与高密度电法探测结果进行对比分析,二者异常对应良好,都反映了已知塌陷区.此次抢险探测结果表明,OCTEM设备轻便,施工便捷,作业效率高,适合浅层快速探测,可用于公路隧道塌陷区快速探测.     

Identification and evaluation of the hydrogeochemical processes of the lower part of Wadi Siham catchment area, Tihama plain, Yemen

One hundred forty-eight groundwater samples were collected from the lower part of Wadi Siham catchment area for hydrogeochemical investigations to understand the hydrogeochemical processes affecting groundwater chemistry and their relation with groundwater quality. Groundwater in the study area is abstracted from different aquifers. The study area is characterized by arid climate and extremely high relative humidity. The results indicate that groundwater in the study area is fresh to brackish in nature. The abundance of the major ions is as follows: Na⁺¹?>?Ca⁺²?>?Mg⁺²?≥?K⁺¹ and Cl^?1?>?HCO ₃ ^?1 ?>?SO ₄ ^?2 ?>?NO ₃ ^?1 . Various graphical and ionic ration plots, statistical analyses, and saturation indices calculations have been carried out using chemical data to deduce a hydrochemical evaluation of the study area. The prevailing hydrogeochemical processes operating in the study area are dissolution, mixing, evaporation, ion exchange, and weathering of silicate minerals in the eastern part (recharge areas). The reverse ion exchange and seawater intrusion control the groundwater chemistry along the Red Sea coast areas and few parts of the study area. Deterioration in groundwater quality from anthropogenic activities has resulted from saltwater intrusion along the coastal areas due to groundwater overpumping and extensive use of fertilizers and infiltration of sewage water. Salinity and nitrate contamination are the two major problems in the area, which is alarming considering the use of this water for drinking.     

Groundwater recharge,flow and hydrogeochemical evolution in a complex volcanic aquifer system,central Ethiopia

Hydrochemical, multivariate statistical and inverse hydrogeochemical modeling techniques were used to investigate groundwater recharge, flow and the hydrochemical evolution within the Akaki volcanic aquifer system, central Ethiopia. The hydrochemical and multivariate statistical techniques are mutually supportive and the extracted information was analyzed together with environmental isotope data. Results reveal five spatial groundwater zones with defined hydrochemical facies, residence times, stable isotopic signals and hydrochemical evolution. These zones are designated as the (1) Intoto, (2) central, (3) Filwuha fault, (4) south zones and (5) a highly polluted sub-sector identified within the central zone. Both the hydrochemical and multivariate statistical analyses have shown the central sub-sector as being spite of differentially polluted by , Cl⁻ and and its tritium content shows recent recharge. Due to the fact that the main recharge source is precipitation, the hydrochemical and environmental isotope data clearly indicated that the central and southern sectors are also recharged from domestic waste water and leakage from water mains and reservoirs. Inverse hydrogeochemical modeling demonstrated reactions of silicate minerals in a CO₂ open system and precipitation of kaolinite, chalcedony, and rare calcite satisfy the observed change in water chemistry from north to south following the regional flow direction.

---

Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.

---

Résumé Des techniques relevant de l’hydrochimie, des statistiques multivariées et de la modélisation inverse hydrogéochimique, ont été utilisées dans le cadre de l’étude de la recharge des eaux souterraines, de l’écoulement et de l’évolution hydrochimique dans le système volcanique aquifère d’Akaki au centre de l’Ethiopie. Les techniques hydrochimiques et multivariées se supportent mutuellement et l’information extraite a été analysée avec les données isotopiques environnementales, des temps de résidence, des signaux isotopiques stables et une évolution hydrochimique. Ces zones ont été désignées comme le (1) Intoto, (2) le centre, (3) la faille de Filwuha, (4) les zones sud et (5) un sous-secteur fortement pollué identifié dans la zone centrale. Les analyses statistiques hydrochimiques et multivariées ont montré que le sous-secteur central a été différemment pollué par , Cl⁻ et , tandis que la teneur en tritium montre une recharge récente. Malgré le fait que la principale source de recharge soit les précipitations, les données hydrochimiques et isotopiques indiquent clairement que les secteurs centres et sud sont également rechargés par les eaux usées domestiques et les fuites de réservoirs et canalisations d’eau. La modélisation hydrogéochimique inverse a démontré les réactions des minéraux silicatés dans un système ouvert au CO₂, et la précipitation de kaolinite, de calcédoine, et la rareté de la calcite satisfont les changements observés dans la chimie de l’eau du nord vers le sud en suivant la direction régionale de l’écoulement.

---

Resumen Se utilizaron la hidroquímica y técnicas de modelación hidrogeoquímica inversa y estadística multivariada, para investigar la recarga del agua subterránea, el flujo y la evolución hidroquímica, dentro del sistema acuífero volcánico Akaki, Etiopía Central. La hidroquímica y las técnicas estadísticas multivariadas se complementan entre si y la información así extraída se analizó junto con los datos de isótopos ambientales. Los resultados revelan cinco zonas diferentes de agua subterránea, con facies hidroquímicas, tiempos de residencia, improntas isotópicas estables y una evolución hidroquímica definidas. Estas zonas se designan como (1) Intoto, (2) Central, (3) Falla de Filwuha, (4) las Zonas del sur y (5) un sub-sector altamente contaminado identificado dentro de la zona central. Tanto los análisis estadísticos multivariados como la hidroquímica, han mostrado al sub-sector central como contaminado diferencialmente por , Cl⁻ y y su contenido de tritio muestra una recarga reciente. A pesar del hecho que la fuente principal de recarga es la precipitación, los datos de hidroquímica y de isótopos ambientales indican que los sectores central y del sur, también se recargan a partir de agua doméstica usada y del goteo de las conducciones del acueducto y de sus reservorios. El modelamiento hidrogeoquímico inverso demostró reacciones de minerales silicatados en un sistema de CO₂ abierto, y la precipitación de caolinita, calcedonia, y rara vez de calcita, satisfacen el cambio observado en la química de agua del norte a sur, siguiendo la dirección del flujo regional.

     

水文地球化学方法在赣地横径地区地热水成因分析中的应用

本文根据从横径地区获得的温泉水、气体和同位素化学成分资料，系统地研究了该区地热水的成因。水、气体、同位素地球化学研究表明，横径地区热水的形成与岩浆和火山活动无关；地热水主要起源于大气降水，其中气体组分起源于大气、地壳和地幔的混合；地热水处在中低温的地热储中；地热水的补给区位于乌泥障地区，其补给区可能的高程为337．5－743．6m。