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1.
盐类在金属、非金属成矿过程中的作用 总被引：2，自引：0，他引：2
盐类与金属、油气、固体非金属矿床经常相互共生,在其成矿过程中起到了不可忽视的作用.在成矿过程中提供金属物质和部分硫源,为矿床的形成提供了有利的容矿空间.作为良好的矿化剂增强了在流体活动过程中萃取岩石中的金属(不一定要有高含量)的能力,对金属的活化、迁移与沉淀起到了渗滤、扩散、混染、交代、溶蚀、氧化还原和沸腾等作用.在石油、天然气形成过程中,无机盐类促使干酪根热解生烃,并可作烃源岩;盐类可充当盖层,并对油气的圈闭、运移和保存有控制作用. 相似文献
2.
《International Geology Review》2012,54(5):691-698
An analysis of the calcium chloride brines and the composition of the host rocks occurring in the Bajocian volcanic formation indicate that these formations represent the parent rocks in which the calcium chloride brines were generated. The original brines were of the sodium chloride type and were altered to calcium chloride as the result of ion exchange between the brine and minerals of the rocks and the process of zeolitization, resulting in concentrated calcium chloride brines. — E.A. Alexandrov. 相似文献
3.
G. M. E. Kamh 《Environmental Geology》2007,52(8):1539-1547
Al-hambra is an immense and valuable archaeological site in Spain built on Sabika hill with red brick and natural sandy limestone.
It exhibits weathering features indicating salt weathering process. The main aim of this study is to examine weathering processes
and intensity acting on Al-hambra. Rock petrography and mineralogical composition have been examined using thin sections,
scanning electron microscope, X-ray diffraction and X-ray fluorescence; limits of rock’s physical parameters using ultrasonic
waves and mercury porosimeter; rock salt content through hydrochemical analysis. Salts attacking this structure are mainly
from wet deposition of air pollutants on the long term chemical alteration of rock’s carbonate content to its equivalent salts.
The salts’ concentration limit within the examined rock samples is considerably low but it is effective on the long run through
hydration of sulphate salts and/or crystallization of chloride salts. Rock texture type and its silica as well as clay content
reduces its resistance to internal stresses by salts as well as wetting and drying cycles at such humid area. The recession
in limits of physical parameters examined for deep seated and weathered limestone samples quantitatively reflects weathering
intensity on Al-hambra. 相似文献
4.
Onondaga Lake is a moderately saline, eutrophic lake characterized by waters rich in calcium, sodium, chloride and bicarbonate. Large quantities of CaCO3 that are precipitated in the lake result from excess calcium supplied as calcium chloride wastes produced by soda-ash manufacturing to lake waters that are at or near saturation with respect to CaCO3 from solution of carbonate rocks in the drainage basin. Beaches along the leeward (northeastern) shore of the lake are composed almost entirely of oncolites ranging from a few millimeters to several centimeters in maximum dimension. Offshore, in 1–2 m of water, the oncolites are biscuit-shaped concretions as much as 15 cm in diameter. The oncolites consist mainly of low-magnesium calcite, but dissolution of the carbonate with dilute acid results in a mass of blue-green algal filaments of the same approximate size and shape as the original oncolite. Most oncolites have an obvious nucleus; the most common nucleus is the hollow stem and cortication tubules of charophytes. Charophytes do not occur in Onondaga Lake today although they are common in other limestone-bedrock lakes in central New York State. Charophytes probably were eliminated by the marked increases in salinity of the lake that resulted from the introduction of soda-ash manufacturing on the lake shores around 1880 which means that growth of the oncolites began at least 100 years ago. 相似文献
5.
Paul Thorn 《Hydrogeology Journal》2011,19(2):445-461
Elevated salinity in groundwater (over 250?mg/l chloride) in a fractured chalk aquifer in the municipality of Greve, Denmark, has been attributed to seawater intrusion from the Baltic Sea, resulting in the closure of a number of wells nearest to the coastline. However, a recent study in eastern Denmark shows that the salinity could also be from ancient connate pore waters. Historical chemistry data from bulk-water samples collected from wells have been used to determine the source. The sample data were studied with respect to their historical changes and temporal trends in chloride, carbonate, sulfate, sodium, potassium, magnesium, and calcium. Wells in the southern third of the municipality are relatively low in sodium and carbonate and high in chloride and calcium/magnesium, indicating waters undergoing saline intrusion. Wells in the northern two-thirds of the municipality are high in carbonate and sodium, but low in chloride and calcium/magnesium, indicating a freshening of the aquifer. This is confirmed by the temporal trends in chloride, where chloride levels in the northern wells remain constant, whereas in the south, chloride increases as abstraction continues. Therefore close monitoring for seawater intrusion should be conducted in the southern third of the municipality. 相似文献
6.
Huanzhang Lu 《中国地球化学学报》1983,2(1):45-57
The Fankou Pb-Zn ore deposit occurs in Devonian and Carboniferous carbonate rocks. This deposit was thought to be a hydrothermal ore deposit related to a granite, but the present research suggests it is a stratabound, stratiform mineral deposit. As a result of geological studies, primary sedimentary and later replacement features were found. Part of some ore bodies are concordant with the host rocks, but most are discordant lenses and veins in the carbonate rocks. Thus there are two types of ores, primary sedimentary and later replacement. The replacement type is very common. Isotopic studies indicate that most of the Pb and S are of sedimentary origin, but part of Pb is of radioactive origin, possibly introduced during later replacement. A regional geochemical survey indicates that the Pb and Zn contents of the Fankou region are respectively 1.5 and 3 times the primary sedimentary type. Gas-liquid fluid inclusions were found in the replacement type ore but not in the primary sedimentary type. The fluid which replaced the primary sedimentary rocks had temperatures of 100–200°C, with a salinity of 3–6 wt. % NaCl equiv. Under the action of such fluid the original sedimentary rocks were replaced to form the present ore deposit. 相似文献
7.
The monthly geochemical study of Bizerte lagoon principal affluent water consists in characterizing the water geochemical facies and their inorganic pollution degree by nutrients. The major elements analysis shows calcium sulfate to chloride calcium balanced facies. The geochemical analysis of water nutritive salts shows generally a good to excellent quality. Wadi Guenniche is considered more polluted as we recorded the highest nutrients contents. The principal component analysis of the connections between the physicochemical and geochemical parameters of Bizerte lagoon affluent water show that the low salinities, the turbidity, and the low contents of major sodium, chloride ions, and nutritive elements are the major factors of the environment controlling the good quality of this fresh water. 相似文献
8.
The Porto Alegre region, Southern Brazil, comprises a fractured aquifer system constituted by pre-Cambrian granitic and gneissic
rocks, and a porous aquifer system formed by Cenozoic muddy–sandy to sandy sediments. A model is presented for the origin
of the fluoride in the groundwater of the fractured aquifer system, based on ionic interrelations, a statistical analysis
of physicochemical parameters and geochemical modeling. The fluoride is present at levels of up to 6.13 mg/L in groundwater
and it arises due to the dissolution of secondary fluorite filling fractures in the granitic and gneissic rocks. The dissolution
of fluorite occurs at the same time as calcite and dolomite solubilization. The statistical analysis identified three chemically
distinct groups (named 1, 2 and 3) and two subgroups (1A and 1B) of groundwater in the fractured aquifer. The most significant
differences between these groups are the different concentration ranges of fluoride, calcium, bicarbonate, magnesium, total
dissolved solids and chloride and pH values, as well as the correlations between them. The compositional evolution of each
groundwater group is governed mainly by how much high-salinity groundwater from the porous aquifer system is mixed with them
and the different thermodynamic equilibrium conditions of calcite, dolomite and fluorite. 相似文献
9.
川西磷酸岩的特征,对阐明磷的沉积作用和磷块岩的成因,有一定的重要性。多年来,四川省地质局在该区作了大量的详细的勘查和研究。这里仅就我们的工作所及,讨论磷酸岩的一些沉积学问题。一、含磷岩系的岩性序列与岩相系列掌握含矿岩系本身在纵横两个方向上变化更替的规律,对沉积矿床的勘查是很重要的。这种变化规律,可以用岩性序列与岩相系列表示之。岩性序列是含矿岩系的各个岩类在纵剖面上转换的次序,反映它成生时期沉积盆地的地质、自然地理、物理、化学和生物等诸方面的状况及其在时间上的演化;而岩相系列则是含矿岩系的各个岩类及其组合在横向上的转换次序,反映上述诸方面状况在空间上的演变。 相似文献
10.
The study of “productive” intervals of the Gremyachinsk potash deposit showed that the precipitation of potassic and potassic–magnesium salts was accompanied by large-scale desalting of sodium chloride owing to the interaction of concentrated solutions from the given part of the saliferous basin with diluted solutions. The constant influx of diluted brine was characterized by the high content of sodium chloride, which led to the large-scale precipitation of halite as lenses, crusts, and accumulations of random morphology. Based on the ultramicrochemical analysis of the composition of brine inclusions in halites of different stages of densification, it is suggested that this process was accompanied by the growth of K ion concentrations in the brine and the subsequent desalting of potassium chloride in the carnallite stage brine with the formation of rocks of the carnallite–sylvinite paragenesis. 相似文献
11.
Solubilities of amorphous silica were determined in separate aqueous solutions of sodium chloride, sodium sulfate, magnesium chloride, and magnesium sulfate at temperatures up to 350°C. These salts, of strong interest in hydrothermal oceanography and geothermal energy, generally ranged in concentration from zero to saturation. Solubilities in the sodium chloride solutions followed closely earlier observed decreases in sodium nitrate solutions at high temperatures.Amorphous silica solubilities were depressed most by magnesium chloride, followed by magnesium sulfate, and less by sodium chloride. As the temperature rose the relative decrease in solubility caused by added salt became smaller. Surprisingly, sodium sulfate solutions, showing little effect at 25°C, sharply raised the solubility as the temperature increased to 350°C. Plots of the logarithms of derived activity coefficients against molalities of added salt gave approximately straight lines. These plots allow simple predictions of amorphous silica solubility in single salt solutions. 相似文献
12.
Evaluation of groundwater quality in the Cihanbeyli basin, Konya, Central Anatolia, Turkey 总被引：2，自引：2，他引：0
The Cihanbeyli basin is located in the northern part of Konya in the Central Anatolian region, Turkey and is characterized by semi-arid climatic conditions and scarcity in water resources. The suitability of groundwater quality for drinking and agricultural purposes in the Cihanbeyli basin was assessed by measuring physicochemical parameters, including major cation and anion compositions, pH, total dissolved solid, electrical conductivity, and total hardness. For this purpose, 54 samples were collected from different sources viz. deep wells, shallow wells, and springs. Results from hydrochemical analyses reveal that groundwater is mostly affected by salty and gypsiferous lithologies. Evaporite minerals such as gypsum, anhydrite, and chloride salts make high contributions from the recharge areas (west, northwest, and southwest parts) toward the discharge area (central and eastern parts). High values of total dissolved solids in groundwater are associated with high concentrations of all major ions. A comparison of groundwater quality in relation to drinking water standards showed that most of the water samples are not suitable for drinking. Based on sodium absorption ratio values and percent sodium, salinity appears to be responsible for the poor groundwater quality, rendering most of the samples unsuitable for irrigation usage. It is concluded that evaporation and mineral dissolution are the main processes that determine major ion compositions. 相似文献
13.
Geochemical Evolution of Great Salt Lake, Utah, USA 总被引：1，自引：0，他引：1
Blair F. Jones David L. Naftz Ronald J. Spencer Charles G. Oviatt 《Aquatic Geochemistry》2009,15(1-2):95-121
The Great Salt Lake (GSL) of Utah, USA, is the largest saline lake in North America, and its brines are some of the most concentrated anywhere in the world. The lake occupies a closed basin system whose chemistry reflects solute inputs from the weathering of a diverse suite of rocks in its drainage basin. GSL is the remnant of a much larger lacustrine body, Lake Bonneville, and it has a long history of carbonate deposition. Inflow to the lake is from three major rivers that drain mountain ranges to the east and empty into the southern arm of the lake, from precipitation directly on the lake, and from minor groundwater inflow. Outflow is by evaporation. The greatest solute inputs are from calcium bicarbonate river waters mixed with sodium chloride-type springs and groundwaters. Prior to 1930 the lake concentration inversely tracked lake volume, which reflected climatic variation in the drainage, but since then salt precipitation and re-solution, primarily halite and mirabilite, have periodically modified lake-brine chemistry through density stratification and compositional differentiation. In addition, construction of a railway causeway has restricted circulation, nearly isolating the northern from the southern part of the lake, leading to halite precipitation in the north. These and other conditions have created brine differentiation, mixing, and fractional precipitation of salts as major factors in solute evolution. Pore fluids and diagenetic reactions have been identified as important sources and especially sinks for CaCO3, Mg, and K in the lake, depending on the concentration gradient and clays. 相似文献
14.
Vesna Matović Suzana Erić Danica Srećković-Batoćanin Philippe Colomban Aleksandar Kremenović 《Environmental Earth Sciences》2014,72(6):1939-1951
Blocks of limestone and sandstone used in walls of the Manasija Monastery complex showed damage caused by the efflorescence and subflorescence of different salts in a low-pollution rural environment. In addition to common salts such as thenardite, thermonatrite, trona and gypsum, a small amount of eugsterite and darapskite was also present. Although these sodium and sodium–calcium salts formed where cement mortar was used for repairs, the lithological type and chemical composition of the substrate also had an influence on the development of distinct salts. The interaction between limestone and sandstone (substrates) and a solution rich in sodium (without calcium) was successfully simulated in the laboratory. The presence of gypsum and sodium–calcium sulphate, as experimental products, solely on the limestones indicated that, in addition to the cement-mortar solution, part of the calcium required for the formation of calcium and double sodium–calcium salts could occur from this substrate. 相似文献
15.
陕西富平上奥陶统赵老峪组发育了一套与深水碳酸盐岩伴生的硅质岩沉积,其地化特征对揭示硅质来源及构造背景等具有重要意义.在研究区地层野外剖面实测、硅质岩岩石地化分析基础上,研究了该区硅质岩硅质来源及构造环境.赵老峪组岩性以深灰色薄板状灰岩为主,夹层状放射虫硅质岩、砾屑灰岩、砂屑灰岩、含斑块灰岩和火山凝灰岩,其中硅质岩呈隐晶质－微晶质,含放射虫化石.样品Al/（Al+Fe+Mn）均值0.68,MnO/TiO2均值0.18,ΣREE均值46.41,δCe均值0.95,δEu均值1.13,LaN/YbN均值1.15,LaN/CeN均值1.08,显示大陆边缘的构造环境,硅质来源主要为陆源来源.结果表明赵老峪组硅质岩发育于奥陶纪扬子板块向华北板块俯冲背景下,形成于华北地块南缘与北秦岭之间的二郎坪弧后前陆盆地北部大陆边缘. 相似文献
16.
M. De Fino L. La Volpe A. Peccerillo G. Piccarreta G. Poli 《Contributions to Mineralogy and Petrology》1986,92(2):135-145
The paper presents major and trace element data and mineral compositions for a series of foiditic-tephritic to phonolitic rocks coming from Monte Vulture, Southern Italy, and investigates their origin, evolution and relationship with the other centres of the Roman province.Major and trace element variation in the foiditic to tephritic suite agrees with a hypothesis of evolution by simple crystal/liquid fractionation, whereas the early erupted phonolitic trachytes and phonolites have geochemical characteristics which do not support their derivation from tephritic magma by crystal fractionation. Foiditic and phonolitic rocks have mineral compositions which are interpreted as indicating magma mixing. However geochemical evidence shows that this process did not play an important role during the magma evolution.The Vulture rocks have compositional peculiarities such as high abundance of Na2O, CaO, Cl and S, when compared with other Roman volcanics. Instead, the distribution of incompatible elements is similar to those of Roman rocks, except for a lower content of Rb and K, higher P and lower Th/Ta and Th/Nb ratios which are still close to the values of arc volcanics.The high contents of Na, Ca and of volatile components are tentatively attributed to the interaction of magma with aqueous solutions, rich in calcium sulphate and sodium chloride, related to the Miocene or Triassic evaporites occurring within the sedimentary sequence underlying the volcano. The distribution pattern of the incompatible elements is interpreted as indicative of magma-forming in a subduction modified upper mantle and of the peculiar location of M. Vulture. 相似文献
17.
Suitability assessment of shallow and deep groundwaters for drinking and irrigation use in the El Khairat aquifer (Enfidha, Tunisian Sahel) 总被引：2，自引：1，他引：1
The El Khairat aquifer is an important groundwater aquiferous system, which is considered a major source for drinking and
irrigation water in Enfidha in Tunisian Sahel. The analysis of groundwater chemical characteristics provides much important
information useful in water resources management. Assessing the water quality status for special use is the main objective
of any water monitoring studies. An attempt has been made for the first time in this region to appreciate the quality and/or
the suitability of shallow and deep groundwater for drinking and irrigation. In order to attend this objective, a total of
35 representative water samples were collected during February 2007 from both boreholes (17) and wells (18); and analyzed
for the major cations (sodium, calcium, magnesium and potassium) and anions (chloride, sulphate, bicarbonate, and nitrate)
along with various physical and chemical parameters (temperature, pH, total dissolved salts, and electrical conductivity).
Based on the physico-chemical analyses, irrigation quality parameters like sodium absorption ratio (SAR), residual sodium
carbonate (RSC), percentage of sodium (Na%), and permeability index (PI) were calculated. In addition to this, iso-concentration
maps were constructed using the geographic information system to delineate spatial variation of qualitative parameters of
groundwater samples. The correlation of the analytical data has been attempted by plotting different graphical representations
such as Piper, Wilcox, and US Salinity Laboratory for the classification of water. The suitability of the water from the groundwater
sources for drinking and irrigation purposes was evaluated by comparing the values of different water quality parameters with
World Health Organization guideline values for drinking water. A preliminary hydrochemical characterization shows that most
of the groundwater samples fall in the field of calcium–magnesium–chloride–sulphate type of water. Majority of the samples
are not suitable for drinking purposes and far from drinking water standards. The high EC value and the percentage of Na in
most of the groundwater render it unsuitable for irrigation. Wilcox classification suggested that around 50% of both deep
and shallow groundwater samples are unsuitable for irrigation. According to the US Salinity Classification, most of the groundwater
is unsuitable for irrigation unless special measures are adopted. 相似文献
18.
济阳凹陷火山岩的岩石学与地球化学 总被引：3，自引：1，他引：3
对济阳凹陷的第三系火山岩、基性侵入岩进行了岩石学和地球化学研究,分别总结了火山岩、基性侵入岩岩石类型及其特征。碱性系列玄武岩主要为钠质系列,具上地幔来源的特征。从古新统到渐新统,玄武岩熔融程度降低,岩浆地幔源深度增加。微量元素和同位素的数据表明,第三纪火山岩源区存在不协调现象。稀土元素分析表明,本区玄武岩为大陆裂谷成因。钐-钕、铷-锶及铅同位素的数据表明,火山岩与侵入岩同源,都来自上地幔。玄武岩浆在形成过程中有过不同程度的混合作用,Rb/Sr相关性表明早、晚第三纪的幔源类型上存在差别。第三纪火山岩数据点分布于DMM,EMIH和EMII三个端元之间,反映第三纪火山岩成因与这三个端元不同程度混合有关。本区火山岩成因与幔源有关,地幔不相容成分的特征表明有沉积物混入的可能,不排除是陆壳物质混入,不同深度岩浆的混合也是一种解释。 相似文献
19.
The groundwater in Wadi Queh exists in two main hydrogeological units; fractured Precambrian basement and sedimentary rocks with high contribution for groundwater recharge. To study the impacts of phosphate mining activities on the groundwater quality in the area, three groundwater samples that represent all water wells in the area were collected and analysed for major ions and some heavy metals. In addition, three bulk samples representing the phosphatic sediments collected from upstream and downstream of the drainage basin were collected and analysed to understand the source of groundwater contamination. The total concentrations of dissolved solids suggest that the groundwater in the area grades from fresh to brackish water (961–1,580 mg/l), and is characterized by sodium–calcium–sulphate–chloride and sodium–magnesium–sulphate–chloride chemical types. The results showed high concentrations of the heavy metals in well nos. 1 and 2 in downstream parts compared to well no. 3 in upstream part reflecting their influence by the mining activities. 相似文献
20.
Groundwater salinization of the Sfax superficial aquifer,Tunisia 总被引：5，自引：0，他引：5
Groundwater salinization has become a crucial environmental problem worldwide and is considered the most widespread form of groundwater contamination. The origin of salinity in the coastal aquifer of the Sfax Basin, Tunisia was investigated by means of chemical analyses of groundwater samples from 65 wells. The groundwater samples present a clear gradation from calcium sulphate salinization to that of sodium chloride. The saturation indices for calcite and gypsum, and binary diagrams of different ions, together with multivariate analysis, indicate the existence of various salinization processes such as: dissolution of gypsum and calcite dispersed through the reservoir rock; ion exchange; intensive agricultural practices that produce effluents that infiltrate to the saturated zone; and sea-water intrusion, enhanced by excessive withdrawal of groundwater. 相似文献