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The purpose of this research was to identify the major environmental impacts occurring in Melo Creek, Minas Gerais, Brazil, especially as regards to its water quality.

Initial evaluation was based on aerial photograph interpretation. All the small creek catchments were delimited and 12 stream segments were chosen for sampling and analyses. The segments had their water discharge calculated and channel pattern described. Also determined for these segments were the physical and chemical parameters of the water, as well as the microbiological content. Both water and sediment samples were analyzed for metals and trace element quantification. Meanwhile, an environmental inquiry was conducted in all the small villages along the creek.

Data show a decrease in water discharge during the last decades, related to the increased destruction of the Atlantic Forest, especially at the riverheads and in permanent preservation areas (PPA). Most of the native vegetation was cut down to create farmlands and pasture. The water quality is also diminishing because for most of the properties, the main activities are pig raising and sugarcane liqueur production, which discharge their untreated effluents, along with domestic wastewater and sewage, directly into the creek. The results indicated that during its passage through the catchment, stream water became significantly contaminated with fecal coliform bacteria. As a consequence, the area possesses a high endemic disease index for water transmitted parasitism, especially for Schistosomiasis mansoni.

This was the first study done in the Melo catchment, a small rural basin without basic sanitation and with a highly prevalent schistosomiasis rate.

This paper describes the organic geochemical characteristics and their roles on barium enrichment in the No. 2 Coal from Huanglong Jurassic Coalfield, China. A total of 18 bench samples were taken from Huangling Mine 2. The average content of barium (3701 mg/kg) was about 23 times higher than that of common world coals. Terrestrial higher plants were the main coal-forming parent material. Relying on the parameters of OEP, Pr/Ph and so on, there is little correlation between organic geochemical characteristics and barium enrichment. Therefore, organic material has little influence on the process of coal-forming and the enrichment of barium.

In this paper, the geochemical characteristics of the trace elements of the No. 6 coal seam from Tanggongta mine, Jungar Coalfield, were studied using the methods of an energydispersive X-ray spectrometer (SEM-EDX) analysis, X-ray powder diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence spectrometric (XRF) techniques. The content of sulfur ranges from 0.09% to 2.83% (1.09% on average). The ash is from 11.70% to 31.47% (20.72% on average), and the moisture is from 2.72% to 6.82% (4.72% on average). The main minerals are kaolinite, carbonate minerals and pyrite. Compared with the average values of Chinese coal, the contents of Ga, Cd, Tl, Li, Sr, and Ag are high. Compared with the values of world coal, Li and Sr are found at high levels. The distribution mode of the REE shows that LREE is concentrated, but HREE is relatively low. The Yinshan Oldland should be the most likely source of the coal’s Li. The bauxite of the Benxi formation could be another source of the coal’s Li in the NE Jungar Coalfield.

A total of 283 coal and parting samples were taken from the Pingshuo mine district, Ningwu coalfield, China. The contents, distribution and enrichment mechanism of 12 hazardous trace elements were studied. The results indicate that Co, Ni, Zn, Cu, Ag and Cr have the chalcophile affinity; Ba, Cd, U are related with clay mineral; Mn is mainly related with carbonate minerals; Pb and Be may be related with sulfide, clay mineral and organic matter. Most of trace elements were associated with terrigenous clastic and clay. The elements (Cr, Pb, Be, Ag, Cu, U, Cd) were enriched in the wet forest and low swamps.

This study aims to present the results of inductively coupled plasma mass spectrometry (ICP-MS) determination of economically significant metals including rare-earth elements and Y (REY), Co + Ni + Cu obtained from the Fe-Mn deposits (FMD) of different areas selected along the Atlantic Ocean.

The description of the instrumental part of the analysis was shown in detail, including the choice of the acquisition mode and other settings of the quadrupole ICP-MS Agilent 7700x, which allow to eliminate spectral overlaps as much as possible and to achieve good precision and accuracy of the measurement. The accuracy of the obtained results was controlled by analysis of certified reference materials (CRM) of Fe-Mn nodules of the US Geological Survey – NOD-A-1 and NOD-P-1, as well as the Russian CRM samples of Fe-Mn nodule OOPE 603 (SDO-6) and ore crust OOPE 604 (SDO-7). Statistical processing of the analysis results demonstrated the acceptability of chosen sample preparation technique and ICP-MS tunes for the determination of REY in FMD.

The performed analytical research allowed giving a geochemical characteristic of studied FMD. The precision for the elements to be determined according to the relative standard deviation (RSD) was within 5.0%.

To move away from the subjective visual assessment of the analytical results quality in terms of absence (or presence) of the REE sawtooth distribution, an original objective mathematical method was proposed.

The purpose of this research is to determine the major environmental impacts and, especially, to evaluate the geochemical characteristics of water of the lakes formed in abandoned quarries of ornamental rock of the Campo Belo Metamorphic Complex.

To do so, 12 quarries were chosen to be studied. They were mapped in a detail scale and their rocks were described and sampled for petrography analysis. Whenever present, the lakes were evaluated too. In situ measurements included pH, Eh, conductivity, resistivity, total dissolved solids and temperature. Water samples were collected to determine alkalinity, sulfates, chlorates, turbidity, suspended sediments and the concentrations of major and trace elements using the ICP‐OES.

Abandoned open‐pit mining operations have resulted in the creation of numerous pit lakes. About 90 per cent of the quarries visited and studied were abandoned or interdicted by environmental organs, what will probably lead to its subsequent abandonment. The quarries Borges and Gêmeos were two quarries of the abandoned quarries in the region, which has a lake formed in its trench. Gêmeos and Borges pit lakes analytical data shows clear correlation between the chemical compositions of the solute and the geological characteristics of the quarries. In spite of the differences found, the results showed a relatively quality water according to Brazilian legislation control values.

This was the first study done of pit lakes formed in abandoned ornamental rock quarries of Campo Belo Metamorphic Complex/Minas Gerais – Brazil. This research provides a better understanding of the gneisses pit lakes hydrogeochemistry, a subject neglected in scientific literature.

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration.

Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer.

Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe₂O₃ replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

The contamination of groundwater by natural arsenic is currently a worldwide epidemic. Arsenic-contaminated groundwater has been reported in Argentina, Chile, Mexico, China, Hungary, West Bengal in India, Bangladesh, and Vietnam. Of these regions, Bangladesh and West Bengal are the most seriously affected in terms of the size of the population at risk and magnitude of health problems. Hence, chronic exposure to arsenic >50′′μg/L in drinking water can result in serious health problems. Common symptoms of arsenic-related ailments are skin, cardiovascular, renal, hematological, and respiratory disorders. Therefore, this chapter focuses on nature, origin, and extent of groundwater arsenic contamination, probable causes, and its impacts on food, drinking water, and social coverage. It further discloses mitigation approaches proposed and practiced by the different research groups to combat this problem and finally concludes.

The purpose of this paper is to find the relationship of palaeontology, palaeobotany and coal thickness of Taiyuan Formation during Late Carboniferous – Early Permian Period in Shanxi Province.

This paper selects three regions, namely, Baode, Xishan and Lingchuan, to analyse the distribution characteristics of palaeontology, palaeobotany and variation of coal thickness.

It was found that in a certain period of geological history, palaeontology and palaeobotany play a dominant role in shaping of a coal-bearing basin. Coal seam thickness changes largely from the northwest to the southeast, gradually thinning in Taiyuan Formation.

Palaeontology and palaeobotany play a dominant role in the shaping of a coal-bearing basin.

The purpose of this paper is to examine the presence of geogenic contaminants in groundwater from shallow aquifers of the crystalline basement complex rocks of Ibadan south-western, Nigeria.

A total of 30 drinking water samples, (six samples each from the five major lithologic formations of the study area) were collected from hand dug wells during the rainy season. Atomic absorption spectrophotometry was used to determine concentrations of arsenic, iron and fluoride in drinking water samples and also concentrations of other chemical parameters that could affect the concentrations of the geogenic contaminants including pH, Ca, Mg, Na and SO₄2−. Descriptive statistics, multiple correlation and analysis of variance were used to examine the relationship between the geogenic contaminants and concentration of other chemical parameters while inverse distance weighting was used to produce risk maps.

The results showed Arsenic concentration exceeding the WHO recommended concentration for drinking water in all the samples within the area. Samples from 16.6 per cent of the wells exceeded the recommended limit for fluoride while iron was present in most of the samples within acceptable limits. The study also revealed no significant difference in concentration of contaminants between the geologic formations.

Geogenic contamination has been scarcely studied in Nigeria. This research, therefore, is a paradigm shift in the study of groundwater contamination which had been mainly focused on anthropogenic contaminants. The outcome of this research will engender policy makers and researchers to pay more attention to geogenic contamination than anthropogenic contaminants in Nigeria.