Uranium mining activities have contributed to the distribution and uptake of radionuclides, which have increased the active concentrations of natural radionuclides in environmental media, causing elevated human health risks. The present study aims to assess the spatial distribution characteristics of natural radionuclides in the surface soils and river sediments of the typical granite uranium mining area in South China, as well as investigate the geochemical features of natural radionuclides in the soil and sediments to understand their migration processes. The activity concentrations for ²³⁸U, ²²⁶Ra, ²³²Th, and ⁴⁰K ranged from 17–3925 Bq/kg, 50–1180 Bq/kg, 29–459 Bq/kg, and 240–1890 Bq/kg, respectively. The open-pit mining areas and tailings pond locations exhibited the highest concentrations of activity for all these radionuclides. This distribution points to an elevated potential health risk due to radiological exposure in these specific areas. Additionally, the values of radium equivalent activity (Ra_eq) and annual gonadal dose equivalent (AGDE) in those areas were higher than the limits recommended by ICRP (2021). ²³⁸U and ²²⁶Ra have a significant correlation (0.724), and the cluster analysis was showing a statistically meaningful cluster below 5 indicated that they have similar behavior during parent rock weathering and watershed erosion, and the distribution of ²³²Th and ⁴⁰K were influenced by the addition of rock types. The activity ratios of ²²⁶Ra/²³⁸U, ²²⁶Ra/²³²Th, ²³⁸U/⁴⁰K, and ²²⁶Ra/⁴⁰K variation indicated that ⁴⁰K more mobile than ²²⁶Ra and ²³⁸U, U(VI) was reduced to U(IV) by organic matter in the downstream area and re-entered into the sediment during the sediment surface runoff in the small watershed of the uranium ore open-pit mining area. Therefore, it is necessary to further seal up and repair the tailings landfill area.

Robust U–Pb dating of accessory minerals (e.g., apatite, titanite, wolframite, and cassiterite) by LA-ICP-MS is often impeded by variable contents of common Pb in matrix-matched reference material (RM). Therefore, common Pb needs to be corrected in these RMs analyses that are used as standards to calibrate isotope fractionation during data reduction. In this study, a novel stand-alone computer program (called Isoclock) focused on the deduction of common Pb from RM, and the corrected RM were used for isotope fractionation. A new common Pb correction method was introduced into the program that allows the deduction of common Pb not only in ²⁰⁶Pb and ²⁰⁷Pb, but also in ²⁰⁸Pb, so that both U/Pb and Th/Pb age calculations can be performed. The software contains several processing steps for the raw files of different mass spectrometers. The processing interface contains data import and view, background correction and filtering of outliers, calculation of common Pb for RMs, fractionation calibration, and age calculation. Isoclock is written using the free and open-source Python language and can either run the code directly or by using a graphical interface. Finally, we discuss the main advantages of this software and its geological application using six examples of apatite, cassiterite, titanite, monazite and wolframite U–Pb dating.

The SW Songliao Basin is an extremely significant part of the giant sandstone uranium metallogenic belt in northern China. The Yaojia Formation is the most significant ore-bearing layer in the region. However, the poorly constrained sedimentology of the Yaojia Formation has substantially hindered the understanding of the basin and the exploration of uranium deposits within it. To determine the sedimentology, provenance, and tectonic setting of the Yaojia Formation in the study area, we conducted petrography, whole-rock geochemical analysis, and electron probe research. Based on the results of the study, it appears that the Yaojia Formation sandstone is predominantly composed of lithic sandstone and feldspar lithic sandstone. Uranium exists in two forms: as independent minerals and as adsorption uranium. Pitchblende is the most common independent uranium mineral, with small amounts of coffinite also occurring. The ratios of Sr/Ba, V/(V+Ni), V/Cr, Ni/Co, and (Cu+Mo)/Zn of the samples indicate that the Yaojia Formation was deposited in a sub- to oxygen-rich freshwater environment with a moderately stratified bottom water body and smooth circulation. The geochemical characteristics of the Yaojia Formation sandstones imply that they are primarily derived from felsic igneous rocks in the upper continental crust in active continental margin and continental island arc environments. According to geochemistry and previous detrital zircon U-Pb chronology studies, the Mesozoic and Late Paleozoic felsic igneous rocks of the southern Great Xing’an Mountains are the principal sources of the Yaojia Formation in the SW Songliao Basin. Besides providing sediments for the study area, the uranium-rich felsic igneous rocks in the source areas also represent a long-term, stable, and ideal source of uranium, suggesting substantial potential for uranium exploration in the study area.

The Ordos Basin is an important sandstone-type uranium enrichment region in China, and the Lower Cretaceous Huanhe Formation has attracted significant attention as a newly discovered ore-bearing stratum. To elucidate the provenance, tectonic background, and sedimentary environment constraints on uranium enrichment in the Huanhe Formation sandstone-type uranium deposits, 10 representative sandstone samples from the study area were analyzed by using electron microscopy, X-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), and electron probe microanalysis. Independent uranium minerals in the Yihewusu area of Hangjin Banner were shown for the first time to be composed mainly of coffinite and titanium-uranium oxide, with trace amounts of pitchblende. The major element diagrams of the sandstone and ratios of Sr/Ba, V/Cr, and U/Th and enrichment factors of Mo and U revealed that the source rocks of the Huanhe Formation sandstone in the study area were intermediate-felsic igneous rocks. The tectonic setting is characterized as an active continental margin, with later deposition in brackish-to-marine water environments. The ore-bearing strata indicate a reducing environment, whereas the nonore-bearing strata indicate a weakly oxidizing environment. With reference to previous studies, the sedimentary material primarily originated from the medium-acidic intrusive rocks exposed in the northern portion of the basin, including the Daqing-Wula Mountains, the Yin Mountains, and middle-acidic intrusions along the eastern margin of the Alxa region in the western part of the basin. The uranium-rich granitic pluton of the source area contributed to the preenrichment of uranium in the target sandstone layer. Under oxidizing aqueous conditions, U⁶⁺ migration was activated, whereas under reducing aqueous conditions, U⁶⁺ was reduced to U⁴⁺, resulting in eventual sedimentation of coffinite as ore.

Illegal mining is one of the biggest problems in many coal mines. With the rapid development of the economy, driven by huge economic benefits, some outlaws illegally exploit mineral resources without a mining license, which is destructive and a potential safety hazard. In order to avoid inspection by law enforcement officials, some outlaws, regardless of the cost or risk, privately and surreptitiously excavate coal mines in self-built houses. The coal resources they excavate are shallow coal resources. Because surface buildings can maintain strong and stable radar scattering characteristics over a long time series, in this study, we combined PS-InSAR technology and high-resolution optical remote sensing to extract the subsidence information of surface buildings corresponding to PS point sets and analyzed their spatiotemporal characteristics. Finally, we developed a fast and accurate method for detecting suspected illegal mining sites from building subsidence information over a larger area. We also carried out a case study using Shandi Village, a suburb of Yangquan City, Shanxi Province, China, as our research object. QuickBird-2, WorldView-2 data, and 20 PALSAR scenes were selected for the experimental research, and two illegal mining sites were detected from 29 December 2006 to 9 January 2011. By comparing our results with previous investigation data, it was found that the accuracy rate reached 40% in local areas, and the detection rate reached 66.67%. In addition, the mining periods were basically consistent. This research shows that our method is feasible and has certain engineering applicability and practical value.