Contamination of Water, Dust, Soil, Rock and Urine with Fluoride in Central India

At least 15% of 0.1 million people residing in 117 villages of Tamnar block (Chhattisgarh, central India) are suffering from fluorosis diseases. In this work, the contamination of F- in the environment (i.e. water, soil, rock and urine) of the Tamnar block is described. The concentration variations of F-, Cl-, NO3-, SO42-, Na+, K+, Mg2+, Ca2+, Al, Mn, Fe and Zn in the groundwater are reported. The F- content in the water was ranged from 1.7 - 17 mg/L with mean value of 9.0 ± 3.7 mg/L. Fluoride was enriched up to 3-, 54-, 69- and 244-folds in the urine, soil, dust and rock, respectively. The cluster and factor analysis models were used to apportion sources of F- and other elements in the water.

Geochemistry and Petrogenesis of Tertiary Volcanic Rocks of the Eastern Roodbar, Alborz Mountain, North of Iran

In the Alborz Mountains of the eastern Roodbar (north of Iran), Tertiary volcanic rocks have a variety of composition between olivine basalt, basaltic andesite, pyroxene andesite and andesite. The presence of different xenoliths and xenocrysts is among the evidence of crustal contamination of these rocks. The positive correlations of CaO/Al2O3 vs to MgO and Al2O3 vs. SiO2 are of signs of the olivine and clinopyroxene fractionation in the variation trend of the area rocks. Positive correlations K2O/P2O5 vs with SiO2 and La/Sm vs. K2O/P2O5 demonstrate contamination of magma with the continental crust. The incompatible trace element patterns and their comparison with crustal contents indicate contamination of the rocks of the area with the lower and upper continental crust. Linear trends in the variation diagram of Nb/Y vs. Zr/Y, introduce two different source regions: a MORB source and the other continental crust for the rocks which are the genesis. The variations of Y/Nb vs. Zr/Nb and Rb/Y vs. Nb/Y reveal a crustal contamination of the magma originated from the MORB source. Geochemical studies represent that the area’s rocks were derived from the 15% melting of a mantle source of MORB type with spinel facies within a continental environment, which was contaminated by varying degrees of continental crustal rocks.

Petrogenesis of siliceous high-Mg series:Evidence from Early Paleoproterozoic mafic volcanic rocks of the Vodlozero Domain,Fennoscandian Shield

Compositional peculiarities of the siliceous high-Mg series(SHMS)rocks formed at the Archean-Paleoproterozoic boundary as a function of plume activity are discussed using example of Early Paleoproterozoic mafic volcanic rocks of the Vodlozero Domain,Fennoscandian Shield.These rocks are characterized by wide variations in Mg#(33-67)and Cr contents(25-1123 ppm),LREE enrichment,and weakly negative_(εNd)(from-0.7 to-2.9).The high Gd/Yb ratio in the primitive high-Mg rocks of the Vodlozero Domain suggests their generation from a garnet-bearing source.At the same time,their negative _(εNd)in combination with LREE enrichment points to the crustal contamination.A new model was proposed to explain the remarkable global-scale similarity of SHMS.Such rocks can be generated by the contamination of a high-degree(30%)partial melt derived from a depleted mantle.The lower crustal sanukitoid-type rocks can be considered as a universal crustal contaminant.Modeling showed that such mixing can provide the observed narrow_(εNd)variations in Early Paleoproterozoic volcanics.The Neoarchean sanukitoid suites,which are widespread on all cratons,presumably composed the lower crust at the beginning of the Paleoproterozoic.Therefore,this mechanism can be considered universal for the genesis of the SHMS rocks.The high-to low-Cr rock series can be produced by the fractionation of the mafic melt coupled with an insignificant crustal assimilation of felsic end members of the sanukitoid suite of the Vodlozero Domain en route to the surface,as suggested by the positive correlation of_(εNd)with Cr and Mg#,negative correlation with Th,and slight decrease of_(εNd)in the more evolved varieties.

Assessment of Rock-Eval T_(max) Data in Bambra-2 Well of Barrow Sub-basin, North West Shelf of Australia: A Case Study of Contaminated Rock-Eval Data

The contamination of cuttings and side wall core (SWC) samples in the Bambra 2 well by drilling mud additives and natural hydrocarbons may cause Rock Eval T max (℃) data to be suspect, and affect its utility in the assessment of thermal maturity. The Rock Eval results of 284 cuttings samples, 31 side wall core samples and conventional core samples from the Jurassic Cretaceous sedimentary sequences in the Bambra 2 well are presented in this paper. Significantly lower T max values from cuttings samples compared with T max values from conventional core samples and solvent extracted SWC samples, from the deeper and higher maturity interval, are thought to have been caused by contamination by diesel and other drilling mud additives. The cuttings samples in the Barrow Group of Cretaceous may be contaminated by natural hydrocarbons, resulting their T max values to be 2-10 ℃ lower than a regularly increased T max trend from core samples. This study indicates that more reliable Rock Eval T max data are obtained from the conventional core samples and solvent extracted SWC samples. This study also indicates that the T max values from some SWC samples were also affected by free hydrocarbons, due to the use of diesel as a mud additive as well.

Reduced magma generation and its implications for the Pulang giant porphyry Cu-polymetallic deposit in Northwest Yunnan,China

The Pulang giant porphyry Cu-Mo polymetallic deposit is located in the Zhongdian area in the center of the Sanjiang Tethys tectonic domain,which was formed by the westward subduction of the Garze-Litang oceanic slab beneath the Zhongza massif.Chalcopyrite-pyrrhotite-pyritemolybdenite occurs as disseminations,veins,veinlets,and stockworks distributed in the K-silicate alteration zone in the monzonite porphyry,which is superimposed by propylitization.The chemical compositions of biotite and amphibole analyzed by electron probe microanalysis(EPMA)indicate that the ore-forming magma and exsolved fluids experienced a continuous decrease in the oxygen fugacity(fO_(2)).Primary amphibolite and biotite(type I)crystallized at relatively high temperatures(744-827°C)and low fO_(2)(log fO_(2)=−12.26 to−11.91)during the magmatic stage.Hydrothermal fluids exsolved from the magma have a relatively lower temperature(621-711°C)and fO_(2)(log fO_(2)=−14.36 to−13.32)than the original magma.In addition,the presence of a high abundance of pyrrhotite and an insufficiency of primary magnetite and sulfate in the ore(i.e.,anhydrite and gypsum)indicate that the deposit may be a reduced porphyry deposit.Magma and fluid fO_(2)results,combined with previous research on magmatic fO_(2)at the Pulang deposit,indicate that the magma associated with the reduced Pulang ore assemblages was initially generated as a highly oxidized magma that was subsequently reduced by sedimentary rocks of the Tumugou Formation.

Comprehensive geochemical identification of highly evolved marine carbonate rocks as hydrocarbon-source rocks as exemplified by the Ordos Basin

This study reversed the developing environments of hydrocarbon-source rocks in the Ordos Basin and evaluated carbonate rocks as hydrocarbon-source rocks and their distributions on account of the fact that China’s marine carbonate rocks as hydrocarbon-source rocks are character- ized by intensive thermal evolution and relatively low abundance of organic matter, by taking the Lower Paleozoic of the Ordos Basin for example and in light of the calculated enrichment coefficients of trace elements, the REE distribution patterns, the mathematical statistics analysis of elements and carbon isotopes and their three-dimensional diagrammatization in combination with the necessary organic parameters. As for the Ordos Basin, TOC=0.2% is an important boundary value. Studies have shown that in the strata where TOC is greater than 0.2%, Ba is highly enriched with positive δ 13Ccarb shifts and δ 13Corg less than ?28‰, reflecting a thigh paleo-productivity, high burial amounts of organic matter, relatively good hydrocarbon-generating potentiality and intensive REE fractionation. All these indicated that the settlement rates are low and the geological conditions are good for the preservation of organic matter, hence favoring the development of hydrocarbon-source rocks. The Klimory and Wulalik formations show certain regularities in those aspects and, therefore, they can be regarded as the potential effective hydrocarbon-source rocks. In the strata where total TOC is less than 0.2%, the contents of Ba are low, δ 13Ccarb values are mostly negative, and δ 13Corg values range from ?24‰― ?28‰, demonstrating low burial amounts of organic matter, poor potentialities of hydrocarbon gen- eration, weak REE fractionation and rapid settlement rates. These facts showed that most of the hy- drocarbon-source rocks were formed in shallow-water, high-energy oxidizing environments, thus un- favoring the development of hydrocarbon-source rocks. It is feasible to make use of the geochemical method to comprehensively assess the highly evolved marine carbonates rocks as potential hydro- carbon-source rocks and their distributions.

Possibilities of using silicate rock powder:An overview

This study evaluates the on use of crushed rocks(remineralizers)to increase soil fertility levels and which contributed to increase agricultural productivity,recovery of degraded areas,decontamination of water,and carbon sequestration.The use of these geological materials is part of the assumptions of rock technology and,indirectly,facilitates the achievement of sustainable development goals related to soil management,climate change,and the preservation of water resources.Research over the past 50 years on silicate rocks focused on soil fertility management and agricultural productivity.More recently,the combined use with microorganisms and organic correctives have shown positive results to mitigate soil degradation;to expand carbon sequestration and storage;and to contribute to the adsorption of contaminants from water and soil.In this article we show results obtained in several countries and we show that this technology can contribute to the sustainability of agriculture,as well as to reverse global warming.Although mineral nutrients are released more slowly from these types of inputs,they remain in the soil for a longer time,stimulating the soil biota.In addition,they are a technology to soluble synthetic fertilizers replace,since the few nutrients derived from such inputs not consumed by plants are lost by leaching,contaminating groundwater and water resources.In addition,conventional methods rely heavily on chemical pesticides which cause damage to soil’s microfauna(responsible for the decomposition of organic matter and nutrient cycling)and the loss of organic carbon(in the form of dioxide),which is quickly dispersed in the atmosphere.Silicate rock powders are applied in natura,have long-lasting residual effects and reduce greenhouse gas emissions.

内蒙古河套盆地地表水-浅层地下水化学特征及成因

地表水-地下水的相互作用不仅影响地下水化学演化,而且控制地下水化学组分的空间分布,是地下水研究领域的重要课题之一。在内蒙古河套盆地采集地下水样品58组,雨水和地表水样品32组,分析了主要离子、微量组分和氢氧稳定同位素等18个指标。结果表明,研究区地表水除了受蒸发浓缩作用影响外,还受到人为活动的影响,水中钙离子、硫酸根、硝酸根等组分明显升高。浅层地下水具有与地表水类似的主要组分和同位素特征,表明浅层地下水可能受到地表水的影响。地表水补给进入含水层的过程中,可能发生了硅酸盐矿物的非全等溶解、盐岩全等溶解、重晶石沉淀、硝酸根、铁氧化物矿物和硫酸根还原等作用。其中,铁氧化物矿物的还原是地下水砷含量高的主要原因。此外,砷浓度还受硫酸根还原的影响。因此,地下水-地表水的综合研究有助于揭示地下水的成因及水文地球化学过程。

铜陵舒家店岩体的年代学和地球化学特征研究

舒家店岩体位于长江中下游中部的铜陵断隆区与繁昌断凹区(盆地)的过渡部位,主要的岩石类型有辉石闪长岩、石英闪长玢岩、花岗闪长斑岩、闪长岩以及闪长玢岩。本文通过对岩体中主要岩性-辉石闪长岩锆石LA-ICPMS精确定年、地球化学组成以及Pb同位素的分析,研究舒家店岩体的年代学、岩浆源区、岩浆演化和构造背景等问题。研究显示,舒家店岩体的侵入时间为139.2±2.1Ma(MSWD=2.3,n=12),其活动时代同属于铜陵矿集区岩浆岩活动期,而不属于繁昌火山岩盆地。辉石闪长岩属于高钾钙碱性系列侵入岩,源区可能为接近于EMΠ型富集地幔的交代地幔,岩浆演化的过程中,存在磷灰石、角闪石、辉石、榍石等矿物的结晶分异作用,同时还受到地壳物质的混染作用,是在挤压的构造背景下形成的。

重金属污染物在黏土固化注浆帷幕中的运移规律

基于渗透和弥散作用,探讨了黏土固化注浆帷幕对污染物的阻滞机制,通过土柱试验,分析了注浆帷幕对重金属污染物的渗透性能和弥散性能,采用污染物运移过程数值模拟的一维对流-弥散计算模型,研究了重金属污染物在注浆帷幕中的运移规律。试验表明,不同的污染物质在黏土固化注浆帷幕中的渗透性能和弥散性能不同,镉的迁移速度大于铅。数值计算表明,注浆帷幕的厚度及其渗透性、弥散性和水力梯度等重要控制参数对重金属污染物在帷幕中的运移过程具有显著影响。

磷矿粉稳定铅污染土的溶出特性研究

采用磷矿粉作为稳定剂对铅污染土进行修复处理。通过毒性浸出试验(TCLP),研究磷矿粉稳定铅污染土的溶出特性,探讨了不同磷矿粉掺量和养护龄期对铅、钙溶出量的影响,分析不同初始铅浓度作用下铅、钙的溶出规律。结果表明:铅溶出量随磷矿粉掺量和养护龄期的增加而减小,钙溶出规律与之相反,钙溶出量与铅溶出量存在线性负相关性;稳定污染土和浸出液的pH值受初始铅浓度影响显著,并随着磷矿粉掺量增加而逐渐增大。

贵阳市地表水地下水化学组成:喀斯特水文系统水-岩反应及污染特征

为了解喀斯特地区水-岩相互作用特征和辨别地下水污染物的来源,为揭示人类活动对喀斯特地下水文地球化学环境的影响,研究了贵州省贵阳市不同岩性含水层地下水和地表水的化学特征。结果发现,地表和地下水主要有HCO3型和SO4型以及这两种化学类型的混合型。地下水地表水化学溶解物质主要来源于碳酸盐岩和碎屑沉积岩的化学风化作用,硫酸盐矿物的溶解和硫化物氧化形成的硫酸对岩石矿物的化学风化是导致水体富集硫酸盐的主要因素。区内地表水和地下水的主要污染物质为K+、Na+、Cl-、SO42-和NO3-。这一研究成果为评价地表/地下水环境的质量现状,为喀斯特地区地表水地下水资源的保护和利用提供了科学依据。

赣、粤、湘地区部分硬岩型铀矿山辐射环境污染及治理现状

分析了我国江西、广东和湖南三省几个典型硬岩型铀矿山氡及其子体造成的大气污染,铀、钍、镭等放射性和锰、铬、锌、硫酸根等非放射性水质污染,及废石堆、尾矿库、露天采场废墟等固体辐射环境污染,并阐述了对上述各类污染的治理现状及效果。

新疆北山地区中坡山北镁铁质岩体岩石地球化学与岩石成因

中坡山北镁铁质岩体位于新疆北山裂谷带的中带,岩体形态为相互联通的岩盆状,出露面积约180km^2。由角闪辉长岩、橄榄辉石岩、橄榄辉长岩、苏长辉长岩和斜长岩组成,岩相带呈同心环状展布,相互间呈渐变过渡关系。锆石U-Pb法同位素年龄为274+4Ma。岩相学、岩石化学、造岩矿物晶体化学和稀土元素地球化学特征均显示了非常发育的分离结晶作用。橄榄辉石岩和橄榄辉长岩主要由早期结晶相聚集而成,橄榄石是最初的液相线相,单斜辉石是数量最多的分离结晶相。斜长岩由残余岩浆结晶而成。母岩浆应该是高镁的拉斑玄武岩浆。Nd、Sr、Pb同位素组成和岩石地球化学特征充分证明了岩浆与围岩之间的物质交换。同化混染作用明显地改变了侵入岩的同位素组成和大离子亲石元素丰度。除斜长岩外,各种岩石的TiO_2、Na：O、K_2O、大离子亲石元素和稀土元素丰度均很低,受同化混染作用影响较小的样品的ε_Nd(t)=+6．80,这些特征证明其岩浆源区属亏损型地幔。FeO~*和SiO_2含量证明,熔融作用开始时,源岩为二辉橄榄岩；当熔融作用持续到一定程度时,源岩物质转化为方辉橄榄岩。稀土元素地球化学证明,熔融作用发生于尖晶石稳定域内。综合各方面要素可以证明,中坡山北岩体是塔里木板块二叠纪期间第四种类型地幔源区部分熔融的产物。

攀西裂谷南段鸡街碱性超基性岩矿物学与岩石化学

对攀西裂谷南段云南鸡街碱性超基性岩的岩相学、矿物化学和岩石化学进行了详细研究。单斜辉石和霞石是该岩体的主要造岩矿物,两者互为消长,在霞霓钠辉岩、霓霞岩和磷霞岩中以不同比例组合。辉石多见环带结构,辉石包裹橄榄石的包裹结构和反应边结构发育,共同指示岩浆的快速侵入结晶过程。橄榄石捕掳晶的Fo=75.43～77.42,明显高于同期结晶橄榄石的Fo值(72.02～72.95),可初步判定母岩浆经历了早期的橄榄石分异。通过对全岩主要化学成分及相关组合参数(M、CA、AR、SI、DI)的研究,判定母岩浆系钠质强碱性Si不饱和岩浆。在Harker图解上MgO与其他氧化物均呈良好的相关关系,指示岩浆演化过程中经历了橄榄石和单斜辉石控制的分离结晶作用。lgSI与主量氧化物成分间具有良好的相关关系,指示岩浆演化过程中很少或未受到大陆地壳混染作用。

辽西义县盆地火山岩的基本特征及其成因探讨

通过对辽西义县盆地火山岩的岩石学、矿物学以及地球化学特征的研究，指出本区火山岩属于一套弱碱性、普通型的火山岩系列．通过热力学计算以及对岩石结构和动力学的分析，表明原始岩浆来自上地幔（约６７ｋｍ），并在约１７ｋｍ处（上下地壳附近）形成高位岩浆房．在高位岩浆房中，由于岩浆的双扩散对流作用，发生了伴随有分离结晶作用的液相分异作用，而同化混染作用则发生于岩浆演化的早期。喷出的岩浆成分受断裂切过高位岩浆房的相对位置的控制。

东天山香山中镁铁-超镁铁质岩体岩石学与矿物学特征:对成岩成矿过程的约束

香山中镁铁-超镁铁岩体产出于新疆东天山地区的黄山—镜儿泉镁铁-超镁铁岩带。主要的岩石类型为二辉橄榄岩、(含长)单辉橄榄岩、橄榄辉石岩及角闪辉长岩。矿物学特征显示,岩体造岩矿物的结晶顺序为铬尖晶石→橄榄石→斜方辉石→单斜辉石→斜长石→角闪石。电子探针分析显示,同一侵入期次中各岩相具有良好的过渡渐变关系,钻孔剖面上橄榄石含量与颗粒大小、单斜辉石的成分有随深度连续变化的特征,铬尖晶石则具有良好的Cr→Fe3+、Ti的演化趋势,由此反映岩体的形成主要受结晶分异作用的控制;含长单辉橄榄岩中橄榄石和单斜辉石成分的突然变化显示岩浆结晶过程中受到了地壳物质阶段性的混染;模拟计算表明,橄榄石分离结晶伴随着硫化物的熔离;钻孔ZK3693深度为295~325 m,含长单辉橄榄岩中橄榄石、斜长石、单颗粒单斜辉石成分突然性的变化指示在区间内有新鲜的基性程度更高的岩浆注入,而此区间内矿石的Cu、Ni品位明显高于区间外同一岩相岩体,说明新鲜岩浆的注入是香山中岩体硫化物富集的重要原因。

裂隙岩体中污染物运移过程的数值模拟

基于双重介质理论模型建立了污染物在地下环境中运移的耦合数学模型,给出了有限元离散的数值格式。并以核废料储存过程中核素90Sr为例,采用所建立的数值模型模拟其在裂隙岩体中运移过程,预测了污染物的浓度分布范围和发展趋势。模拟结果表明:核素90Sr在处置库中运行40年后,下游地区的抽水井的浓度可达到3 100 Bq/m3,超出了国家规定的标准,为固体废物场址的选择以及污染的控制提供了决策依据。