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The compositions and transfer processes affecting coastal sea sediments from the Seto Inland Sea and the Pacific Ocean are examined through the construction of comprehensive terrestrial and marine geochemical maps for western Japan. Two-way analysis of variance (ANOVA) suggests that the elemental concentrations of marine sediments vary with particle size, and that this has a greater effect than the regional provenance of the terrestrial material. Cluster analysis is employed to reveal similarities and differences in the geochemistry of coastal sea and stream sediments. This analysis suggests that the geochemical features of fine sands and silts in the marine environment reflect those of stream sediments in the adjacent terrestrial areas. However, gravels and coarse sands do not show this direct relationship, which is likely a result of mineral segregation by strong tidal currents and the denudation of old basement rocks. Finally, the transport processes for the fine-grained sediments are discussed, using the spatial distribution patterns of outliers for those elements enriched in silt and clay. Silty and clayey sediments are found to be transported and dispersed widely by a periodic current in the inner sea, and are selectively deposited at the boundary of different water masses in the outer sea.

The traditional methods for classifying elemental concentrations such as the cumulative frequency method, the logarithmic interval method, and the mean–standard deviation method all have the limitation of depending on a specific dataset. An objective “ruler” that can measure the elemental concentration level regardless of the amount of data (even for a single sample) and enables comparisons among different elements and regions is highly necessary. Recently, the 19-level fixed-value method was proposed as a “ruler” to measure the elemental concentrations of Sn, Li, Mo, and Ni objectively and to facilitate comparisons across elements and regions. However, the method for Au has not been proposed until now. In this paper, we propose the “ruler” for Au, which objectively divides Au concentrations into 19 levels with 18 fixed values from the detection limit to the cut-off grade with easily understood numbers. The “ruler” for Au along with those for Mo and Sn was applied to geochemical survey data at 1:200,000 and 1:50,000 scales, respectively, in the Zhongchuan area of Western Qinling, China, to classify elemental concentrations and draw geochemical maps. The results show that elemental concentrations can be measured using the “ruler” to assess the background, anomaly, and mineralization levels objectively, and the levels can be compared across different elements, regions, and even different scales. Geochemical maps show that in the study area, known gold deposits are all associated with high anomalies or mineralization levels of Au, while the Mo and Sn concentrations are predominantly at background levels. These results are consistent with the known mineral resources in this area. When superimposing geochemical maps of larger scales onto those of smaller scales, the variation in the elemental concentration levels with different survey scales indicates valuable geochemical meanings for mineral exploration.

Geochemical maps are essential visualization tools for studying the distribution patterns of elements on the Earth’s surface. They provide critical insights into geological structure, mineralization processes, and environmental evolution. Traditional interpolation methods often fail to adequately reconstruct high-frequency details in geochemical maps with low sampling density. This study proposes a super-resolution (SR) reconstruction method for geochemical maps based on an enhanced U-Net architecture, validated in the Gouli area of Qinghai Province. By integrating residual blocks, multi-scale neural networks, and constraints from topographic features (elevation, slope, aspect) and geological map embeddings, our method enhances the resolution of stream sediment geochemical maps from 1:50,000 to 1:25,000 scale. Experimental results demonstrate that the proposed method outperforms SRCNN, VDSR, and standard U-Net models in both peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM). Specifically, with all constraints incorporated, the method achieves maximum and mean PSNR values of 38.486 and 25.334, respectively, and maximum and mean SSIM values of 0.968 and 0.817. The reconstructed high-resolution (HR) geochemical maps exhibit superior detail clarity and maintain strong spatial correlation with the original HR data. Studies have shown that this method can effectively learn multi-scale geochemical patterns and detect subtle anomalies missed in low-resolution (LR) maps. Moreover, the reconstructed HR geochemical maps exhibit better alignment with the Ag, Cu, and Pb anomalies in known mineralization zones (Maixiulongwa and Sanchakou areas), thereby providing strong support for precise mineral exploration.

With the explosive growth in demand for lithium (Li) resources, the Mufushan area has been a hotspot for Li deposit exploration in China in recent years. Geochemical maps and geochemical anomaly maps are basic maps in the geochemical exploration of mineral resources. A fixed-value method to contour a Li geochemical map is presented here, in which Li concentrations are divided into 19 levels on 18 fixed values, ranging from 5 μg/g (corresponding to the detection limit) to 1858 μg/g (corresponding to the cut-off grade of Li deposit in hard-rock type) and illustrated in six color tones corresponding to Li areas of low background, high background, low anomaly, high anomaly, mineralization in clay-type, and mineralization in hard-rock type. The geochemical map of Li in the Mufushan area using the new fixed-value method indicates that the study area belongs to the high background area, and the known Li deposits are located in the high anomaly areas. In addition, the geochemical anomaly map of the Mufushan area is drawn using the method of seven levels of classification, and indicates that the known Li deposits are all in the anomaly areas, with anomaly levels not lower than the second level. Furthermore, four other areas are recognized for Li resource potential based on the geochemical map and geochemical anomaly map in the Mufushan area.

Geochemical maps play an important role in mineral resource exploration. There are three traditional methods for creating geochemical maps: the cumulative frequency method, the logarithmic interval method, and the Avg±k∗Std (where Avg and Std are the abbreviations of average and standard deviation, and k is a multiple of Std) method. However, with the increasing scope of the study area and cumulative data, the limitations of traditional methods, which depend on the amount of data, are exposed. A fixed-value method for Sn geological mapping is proposed to overcome the limitations of traditional methods. In the fixed-value method, Sn concentrations are divided into 19 levels on 18 fixed values ranging from 1 μg/g (corresponding to the detection limit) to 1000 μg/g (corresponding to the cut-off grade of Sn in hard rocks). The 19 levels are mapped in six color tones. The first to fifth levels are the lowest background areas in blue tones, which correspond to Sn concentrations ranging from the minimum to 3.4 μg/g. The sixth to ninth levels are high background areas in yellow tones corresponding to concentrations less than 10 μg/g, the 10th to 12th are low anomaly areas in pink tones less than 28 μg/g, the 13th to 15th are high anomaly areas in red tones less than 200 μg/g (corresponding to the placer cut-off grade), the 16th to 18th in gray tones less than 1000 μg/g, and the 19th level is in black corresponding to Sn ores with Sn concentration not less than 1000 μg/g. The fixed-value method along with three traditional methods was used to contour the Sn geochemical maps in the Gejiu area in Southwest China. The illustration results of the presented fixed-value method and three traditional methods for geochemical mapping of Sn are all feasible for Sn deposit exploration in the Gejiu area, Southwest China. Compared to traditional methods, the presented fixed-value method overcomes the flaws of traditional methods and is also more meaningful in geochemistry.

Topsoil geochemistry maps of the city of Sisak were compared with historical maps to explain the geochemistry of the topsoil. Historically, three periods of Sisak's development can be distinguished: 1) the Celtic and Roman period; 2) the Medieval period, and 3) the industrial era during the 20th century. Comparison of the geochemical maps with the historical maps reveals 1) the accumulation of elements in the soil and their preservation over 2,000 years; 2) the influence of infrastructural interventions on the geochemical composition of the topsoil and 3) the high rate of accumulation of potentially toxic elements in the topsoil due to rapid industrialisation on purely arable land.

A The regional geochemical mapping project was conducted by the Centre for Geological Survey, Geological Agency, Ministry of Energy and Mineral Resources during 2011 to 2012 in Banten and West Java Provinces areas. Geological and topographic maps with scale of 1:100.000 as the base maps were used. Stream sediment samples were collected in this geochemical mapping project with the fraction size are 80# and the density of samples represent one sample for about 25 km2. The project already successfully collected 1215 stream sediment samples covering twenty one base maps. The samples collecting were the result of collaboration between Geological Agency and universities. Moreover, the geochemical analysis was conducted with the XRF (X-Ray Fluorescence) method at the Geological Laboratory of Centre for Geological Survey. This method could analyze for 30 elements and show significant anomalies with presuming result from natural product or derived from human or urban activities. The volcanic products from quaternary volcanoes are clearly identified on distribution of As, Ba, Cl, Cu and Zr elements. Epithermal mineralization zone has an anomaly of distribution of Cu, Fe, Pb, and Zn. Meanwhile the human activities are showing from geochemical map of Cl, Cr, Cu, Hg, Pb and Zn that show scattered anomalies localized close to the cities, industries and mining area.

The contents and distribution patterns of alkali and alkaline earth metals in soils and rocks of the southern Cis-Ural region were studied. A database on the contents of these metals was developed, the soils were classified with respect to their provision with these metals, and corresponding schematic maps showing their distribution in soils of the region were compiled. It was found that the contents of these metals decrease from east to west (from the Yuryuzan–Aisk Piedmont Plain to the Ufa Plateau and to the Belebeevsk Upland), and their distribution patterns change. Among alkali metals, the highest accumulation in the soils is typical of potassium, sodium, and cesium; among alkaline earth metals, of strontium and barium.

Geochemical map of western and souther part of Serbia covers an area of about 30 000 km2 and also basins of rivers Ibar, Western Morava, Kolubara, Drina and Grand Morava. Representative samples from relevant profiles were collected according to WEGS (Western European Geochemical association). Samples were collected at the A-horizon at a depth of 15-20 cm from the ground surface; OB-overbank sediments at the depth of 80-100 cm and S-modern stream sediment. Geochemical mapping of lithological members was performed at 66 locations. The contents of natural radionuclides238 U,232 Th and40 K were analyzed. The results are shown on maps at a scale of 1: 1000000. Preserved geochemical record in the coastal profile of river flows will contribute to the assessment of anthropogenic impacts in the environment of rural settlements, particularly in the identification of geopathogenic zones of influence of natural radionuclides on human health. Research results have been shown on geochemical maps, diagrams and tables.

Geochemical mapping based on the stream sediment method has been carried out in the whole of Java Region by the Centre for Geological Survey. The Regional Geochemistry Bandung Quadrangle as part of West Java Region has been mapped in 1:100.000 scale map, base on the Geological Map of Bandung Quadrangle. About 82 stream sediment samples collected and sieved in the 80 mesh sieve fraction during the field work session at 2011. This fraction was prepared and analysed for 30 elements by X-ray fluorescence spectrometry at the Centre for Geological Survey Laboratory. There are some elements indicating significant anomaly in this region, and it is important to determine the present abundance and spatial distribution of the elements for presuming result from natural product or derived from human activities. The volcanic products (Tangkuban Perahu Volcano, Volcanic Rock Complex and Quarternary Volcanic-Alluvial Deposit) are clearly identified on the distribution of As, Ba, Cl, Cu, Zr and La elements. However Mn, Zn, V and Sr are related to precipitation in the Tertiary Sediments, while the influence of human activities are showing from a geochemical map of Cl, Cr, Cu, Pb and Zn that show scattered anomalies localized close to the cities, farming and industries.