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In the present report, thermally stimulated luminescence (TSL) of quartz and limestone samples irradiated with β and γ-rays has been investigated. Herein the formation of trap depths and calculation of kinetic parameters of β and γ - irradiated quartz and limestone samples were studied through thermoluminescence (TL) glow curve analyses. The quartz and limestone samples were collected from various sites of Chhattisgarh (Patharia and Dalli-Rajhara mines). The collected raw samples were annealed at 400 °C. The phase formation of collected samples is confirmed by X-ray diffraction studies. The grain sizes of the samples are determined by using Debye-Scherrer formula. TL glow curves of the collected samples were recorded for various doses of β and γ-rays. Kinetic parameters such as order of kinetics frequency factor and trap depth were calculated by employing CGCD methods. A comparative study on the TL properties of the geological materials under β and γ-irradiation was done. The trap model analysis was executed to determine the nature of traps responsible for dominant TL peaks of β and γ-irradiated limestone and quartz samples. [ABSTRACT FROM AUTHOR]

Summary: A high concentration of Arsenic (As) contamination in ground water has been reported in the village of Kaudikasa in Rajnandgaon district, wherein around 10% of the population is suffering from As-borne diseases. The region does not share any demographic or geological similarity with the sedimentary aquifers of the Bengal Delta Plain in Eastern India, but represents an igneous terrain with elevated As concentrations in groundwater. There is limited information about the source of As in groundwater and its mobility constraints. In this area, almost all the wells are located in the granitic terrain with pegmatitic intrusions. Most of these wells are characterized by As concentration above the World Health Organization () and the BIS (Bureau of Indian Standards) standards, with the highest being found in a well with more than 250μg/L of As. Here we report petrographic studies of the granitic host rock and X-ray diffraction results that indicate that altered realgar (α-As4S4), para realgar (AsS), and/or tennantite (Cu12As4S13), are the main mineral that contain As. This element is leached during the weathering and water–rock interactions. Microprobe analysis of the altered realgar grains of in pegmatitic intrusions of the host granite indicate 23–27wt.% As. Remote sensing is useful to delineate the source of this contaminant, which appears to lie at the intersection of a mineralized NW-SE and N–S lineaments associated with the Kotri rift zone. These lineaments are structurally controlled as rifting followed by thrusting and other types of faulting caused left-lateral displacement of N–S Kotri lineament along a NW-SE fault plane showing sinistral shearing. This process caused water drainage in the areas to flow along these highly mineralized weak zones. Thus, the water becomes highly contaminated due to leaching of minerals at the intersection of these lineaments, clearly visible at two areas of high contamination that lie very near to this intersection over granitic rock. The source of As affecting the Rajnandgaon district is located in granites that have pegmatitic intrusions likely generated by hydrothermal activity. [Copyright &y& Elsevier]