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Papua New Guinea (PNG) is located at the convergence edge of the Pacific Plate and the Indo-Australian Plate, consisting of three units. There are three chromium mineralization types in PNG. Based on national-scale geochemical mapping in PNG during 2015–2018, 1399 samples of stream sediments were collected from Highland Region, Papua Peninsula, and New Guinea Islands. This paper preliminarily studied chromium’s geochemical background, spatial distribution characteristics, and geochemical anomalies. The chromium concentration ranged from 3 ppm to 74,600 ppm, with a median value of 145 ppm, which was higher than the upper crustal abundance of chromium and the chromium geochemical baseline of Europe, Australia, North America, and China. In terms of stream sediment samples in different tectonic units, as mafic–ultramafic magmatic rocks are widely developed, the median chromium values of the New Guinea Orogen, including the Papuan Fold Belt, the New Guinea Thrust Belt, the Finisterre Terrane, the Aure Fold Belt, the Eastern Fold Belt, and the Eastern Papuan Composite Terrane, were higher than the value of the Melanesian Arc. The ophiolitic complexes, such as the April ophiolite, the Marum ophiolite, and the Papua ultramafic belt, significantly correlated with the higher chromium concentration. Eleven chromium high anomalies with mineralization potential were delineated, including three laterite and podiform prospecting areas and eight placer prospecting areas. Based on the chromium–nickel integrated anomaly map, comprehensive exploration and exploitation of nickel and chromium can be carried out in 1 and 11 high anomaly areas related to lateritic mineralization.

Quantification and recognition of geochemical patterns are extremely important for geochemical prospecting and can facilitate a better understanding of regional metallogenesis. Recognition of such patterns with deep learning (DL) algorithms has attracted considerable attention, as these algorithms can generally extract high-level geochemical features and thus create models in which geochemical patterns are fully exploited. These DL algorithms are usually constructed to be compatible and consistent with the underlying data, but their interpretability and pertinent physical constraints (such as granitic intrusions related to magmatic-hydrothermal mineralization) are generally overlooked. This paper introduces a physically constrained variational autoencoder (VAE) architecture to identify geochemical patterns associated with tungsten polymetallic mineralization. We first identify physical constraints from geological characteristics and metallogenic regulation via the methods of fry analysis, standard deviation ellipses, and fractal analysis to reveal the controlling function of granitic intrusions on mineralization. Subsequently, we construct the physical constraints based on the nonlinear controlling function and add the geological constraints into the VAE loss function as a penalty term. After optimization of the network parameters, the well-trained physically constrained VAE architecture can recognize the geochemical anomaly patterns that the conventional VAE cannot. These extracted geochemical anomaly patterns generally show a strong spatial relationship with the granitic intrusions. In addition, the performance measures involving the receiver operating characteristic curve and success-rate further indicate that the generalization accuracy of the conventional VAE can be enhanced via physics-based regularization. These results suggest that the proposed physically constrained VAE, which integrates physical knowledge into the VAE loss function, not only improves the geochemical pattern recognition performance but also demonstrates consistency with geological and physical domain knowledge.

Background Colon adenocarcinoma (COAD) is one of the most common malignancies worldwide. Genomic instability is one of the hallmarks of colon cancer and is associated with prognosis. Nevertheless, the impact of genome instability-associated long non-coding RNAs (lncRNAs) along with their clinical significance in cancers has remained mostly unexplored. Methods In this study, a mutator hypothesis-derived computational frame integrating the somatic mutation profiles and lncRNA expression profiles in a tumor genome was developed, which enabled the identification of 137 novel genomic instability-associated lncRNAs in colon cancer. Subsequently, a genome instability-derived lncRNA signature (GILncSig) segregated the patients into low- and high-risk groups with prominent differences in outcomes. Results Combined with the overall survival data, we established 6 six lncRNA-based signature to predict prognosis, which were LINC00896, AC007996.1, NKILA, AP003555.2, MIRLET7BHG, and AC009237.14. We found that the expression level of PD-L1 (CD274) and somatic mutations in the high-risk group were higher than those in the low-risk group. This suggests that high-risk patients may be sensitive to immunotherapy. We further found that the prognosis of patients in the high-risk group was significantly lower than that of patients in the low-risk group, and that patients' prognosis was likely to be worse as the patient's risk score increased. Conclusions In conclusion, this study explores the role of lncRNAs in genomic instability and cancer prognosis and provides a new idea for the prognostic prediction of colon cancer.

Geochemical baselines are crucial to explore mineral resources and monitor environmental changes. This study presents the first Laos geochemical baseline values of 69 elements. The National-scale Geochemical Mapping Project of Lao People’s Democratic Republic conducted comprehensive stream sediment sampling across Laos, yielding 2079 samples collected at 1 sample/100 km2, and 69 elements were analyzed. Based on the results of LGB value, R-mode factor analysis, and scatter plot analysis, this paper analyzes the relationship between the 69 elements and the geological background, mineralization, hypergene processes and human activities in the study area. The median values of element contents related to the average crustal values were: As, B, Br, Cs, Hf, Li, N, Pb, Sb, Zr, and SiO2, >1.3 times; Ba, Be, Cl, Co, Cr, Cu, F, Ga, Mn, Mo, Ni, S, Sc, Sr, Ti, Tl, V, Zn, Eu, Al2O3, Tot.Fe2O3, MgO, CaO, and Na2O

Geochemical background is the basis of anomaly evaluation in mineral exploration and environmental investigation. However, the background value obtained from secondary media is inevitably affected by weathering, transportation, and sorting, which leads to secondary depletion or enrichment of chemical elements. This problem can be avoided by the geochemical mapping of the exposed crust. In this paper, more than 38,000 samples of rocks data were collected, and an original method was presented for the first time to produce the cobalt geochemical map of exposed crust across the whole of China. Using a geological map grid of 1:200,000 as the basic calculation unit, the area and content of rock types in each unit were calculated, and then the grid was assigned using the area-weighted average method. Based on this, an geochemical contour map was drawn in ArcGIS. The results show that the median of the exposed crust is 9.74 mg/kg, which is lower than that of the whole crust and soils. This value is explained by the vertical heterogeneity of the crust and the secondary enrichment, respectively. Co anomalies and anomalous centers of exposed crust are distributed in southwest, north, and northwest China, where they are primarily related to Permian Emeishan Large Igneous Province (ELIP), Pacific plate, and the big mantle wedge (BMW), Archean metamorphic basic rocks, and ophiolite belts.

The Changkeng–Fuwan Au-Ag deposit is representative in South China, which is located in the southwest of the Qin–Hang metallogenic belt (QHMB). The Au and Ag orebodies are located in the same altered fracture zone, forming independent gold and silver orebodies respectively, with the characteristics of “upper gold and lower silver” in space. Three metallogenic stages have been identified: the pyrite–quartz–sericite stage, the polymetallic sulfide stage, and the quartz–calcite stage. The fluid inclusions (FIs) from the deposit are the two-phase liquid-rich (type I) and the pure liquid FIs (type II). The microthermometric measurements of type I FIs are characterized by temperatures of 158–282 °C and 146–289 °C and salinities of 0.35–9.88 wt.% NaCl equiv. and 0.18–11.70 wt.% NaCl equiv. The H, O, He, and Ar isotopic data show that the ore-forming fluids of the deposit were derived from a mixture of magmatic and meteoric fluids. The C and O isotopic data suggest that the carbon of the fluid may derive from a magmatic source. The S and Pb isotopic data indicate that the primary source of the metals in the Changkeng–Fuwan deposit may be a magma source. Based on the geological characteristics, FI microthermometry, and isotope data (C, H, O, He, Ar, S, and Pb), we propose that the Changkeng–Fuwan deposit should be classified as a far-source low-temperature magmatic–hydrothermal deposit.

The objective of this work was to estimate the influence of climate variability on viticultural zoning and variety regionalisation in China in the past 50 years. A multicriteria climatic indices system, which includes Frost-Free Season (FFS), Dryness Index (DI), and Extreme Low Temperature (ELT), was used to define climatic suitable areas and classify different climate zones for wine grape-growing in China. The Accumulated Effective Temperature (AET) was used as an index of variety regionalisation. Indices were calculated based on daily climatic observations from national ground weather stations throughout China from between 1967 and 2016. The variation trends were analysed by Sen’s slope and Mann-Kendall non-parametric tests in 13 representative wine growing sites. Based on the studied criteria, the suitable viticultural zone exhibited a continuous northward expansion with an average increase of 0.204 million km2/decade, largely due to increasing FFS. A significant increase of FFS was detected in most representative sites, with almost no detectable change of DI during the growing season. The analysis also revealed that the North East Region, Inner Mongolia Region, and Xinjiang Region are the three most profitable wine regions. Movement of the soil-burying line was limited to Shandong and Hebei provinces. Although the suitable viticultural zone increased, the data also revealed a decrease in the area for high quality wine production when considering varietal suitability. These results have important implications for understanding both new opportunities and challenges under changing climate and the latter’s effects on viticultural viability in China. They can also help guide stakeholders to develop adaptive strategies for maintaining the profitability of currently used regions and for developing new regions for viticulture.

The three-dimensional (3-D) electrical structure of the upper-mantle was used to examine the deep origins of and relationship among the Cenozoic volcanoes located in Northeast China (NEC). High-quality, long-period magnetotelluric (LMT) full-impedance tensor data were collected in NEC and subjected to 3-D Gauss-Newton inversion in order to construct a resistivity model. The resulting model reveals the presence of multiple localized low-resistivity anomalies (LRAs) within the high resistivity lithosphere beneath NEC. These LRAs partially coincide with Cenozoic volcanoes on the surface. Three LRAs that form a larger, annular LRA were observed in the deep upper mantle beneath the Songliao Basin, whereas vein-like LRAs were found in the asthenosphere that connect the lithosphere and deep upper mantle. Petrophysical analyses suggest that the LRAs may have been caused by fluid-induced melting. Based on our electrical model, we propose that, following dehydration of the subducted Western Pacific slab into the mantle transition zone (MTZ) beneath NEC, the released water migrated upward and caused partial melting at the top of the MTZ beneath the Songliao Basin. Under the effect of buoyancy, the melted mantle formed a thermal upwelling that caused melting of asthenosphere before diapiring at the base of the dry lithosphere. The magma then penetrated structural boundaries (such as thinner, weaker, or activated suture zones) and finally reached the Earth’s surface. This melting and upwelling of hot mantle materials may have resulted in large-scale volcanism in the region throughout the Cenozoic, including the eruption of Changbai Mountain and Halaha Volcanoes. Our results suggest that the Cenozoic NEC volcanoes may all share a similar mode of genesis, and probably originated from the annular LRA in the deep upper mantle.

In recent years, mineral resources near the surface are becoming scarce, causing focused mineral exploration on concealed deposits in covered terrains. In northern China, covered terrains are widespread and conceal bedrock sequences and mineralization. These represent geochemical challenges for mineral exploration in China. As a deep-penetrating geochemical technology that can reflect the information of deep anomalies, the fine-grained soil prospecting method has achieved ideal test results in arid Gobi Desert covered terrain, semi-arid grassland covered terrain, and alluvium soil covered terrain of northern China. The anomaly range indicated by the fine-grained soil prospecting method is very good with the known ore body location. The corresponding relationship can effectively indicate deep ore bodies and delineate anomalies in unknown areas. Overall, the fine-grained soil prospecting method can be applied to geochemical prospecting and exploration in covered terrains.

Colon adenocarcinoma (COAD) is globally one of the most frequently occurring malignant tumors. The patients' 5-year survival rate with colon cancer was poor. There is a usual form of mRNA modification called N6-methyl adenosine (m6A). It is adjusted by the m6A RNA methylation modulator. Nevertheless, few studies of COAD can fully discuss m6A-related lncRNAs' prognostic function.From The Cancer Genome Atlas (TCGA) database, this study of COAD samples discussed 23 m6A regulator-related lncRNAs systemically. 2 m6A patterns with various clinical results were recognized, and a remarkable correlation between various m6A clusters and tumor immune microenvironment was discovered.According to prognostic analysis, cluster1 had a higher immune checkpoint programmed death-ligand 1 (PD-L1) expression and a better prognosis. A 6 m6A-related lncRNAs model was constructed through least absolute shrinkage and selection operator (LASSO), univariate, multivariate Cox regression and stratified analysis. The outcomes reported that compared with the low-risk group, high-risk groups that were based on model closely were related to poor overall survival (OS). The study ensured a risk model consisting of 6 m6A-related lncRNAs as independent prognosis predictors. For the expression differences between the two groups, Genomes Pathway Analysis, Kyoto Encyclopedia of Genes (KEGG) and Gene Ontology (GO) biological process analyses were conducted. In addition, on the basis of full analysis of OS, a nomogram based on gender, age, lncRNA feature and the stage was constructed. One year, two years, and three years are the periods when the calibration chart performed best.The outcomes of the study confirmed the underlying function of m6A-related lncRNAs and offered fresh perspectives to COAD prognosis.

The concentrations, variations and distribution of molybdenum (Mo) in catchment outlet sediments from China were studied in this contribution based on the results of recently-finished, continental-scale, China Geochemical Baselines (CGB) project. The data from CGB were combined with other published data-sets with the purpose of understanding the spatial distribution of Mo in China and, in addition, relating the observed geochemical features to natural and/or anthropogenic processes. This geochemical mapping with a density of ca. 3000 km2 per site involves catchment sediments in two horizons at each site: a top sample (TOS) at a depth of 0–25 cm and a bottom sample (BOS) at a depth greater than 100 cm. In total, 3382 TOS and 3380 BOS samples were collected. The analytical results show that the concentrations of Mo in the catchment outlet sediments of China range from 0.07 to 57.86 μg/g for the TOS and 0.09–32.43 μg/g for the BOS. The median and mean values of the TOS data are 0.73 and 1.01 μg/g respectively, and those of the BOS data are 0.71 and 0.94 μg/g. The variations of both the TOS and BOS are high at this continental scale. The Mo concentrations vary greatly from one geological and/or geographic unit to another. For instance, from the Cathaysia Block with the TOS and BOS median values of 1.22 and 1.46 μg/g to the North China craton with those of approximately 0.61 and 0.58 μg/g. Various processes govern the spatial distribution of Mo in the catchment sediments of China but regional-scale natural sources (e.g. lithologies) predominate. Sedimentary sandstones and carbonate rocks, alluvium in plain terrain and aeolian materials (e.g. loess) account for the extensive low concentrations ( 1.2 μg/g) in the Yangtze and Cathaysia blocks. Simultaneously, some local mineralized areas can be also identified at this scale because the sampled sites just happened to fall on sediments derived from mineralized rocks or anthropogenic addition by mining activities. Furthermore, the TOS share the similar patterns with the BOS indicating relatively stable inheritance and no apparent extensive secondary enrichment or depletion in the catchment sediments of China. The CGB demonstrates that a series of baseline levels of Mo are needed at different regions and scales and ultra-low density mapping can still deliver robust geochemical patterns.

The 1:1, 000, 000 geochemical mapping across the boundary area of China and Mongolia has acquired high-quality basic geochemical data, yielding more than 9000 stream sediment samples and over 400 rock samples. Each stream sediment and rock sample site was assigned to the regional tectonic unit, geological background and geomorphic landscape maps, respectively, resulting in spatial data for three categorical variables. The contents and spatial distributions of Cu in stream sediment and rock samples across the boundary area of China and Mongolia were studied. The stream sediment geochemical data set was centered logratio transformed (clr) to avoid the closure effect. Random forest regression (RFR) was applied to predict Cu geochemical background for each sample with tectonic unit, geological background, and geomorphic landscape as characteristic variables, then the residuals were used to map geochemical anomalies. The study shows that Cu contents in stream sediments and rocks are high in the west and low in the east of the study area, and the median Cu varies with different tectonic units, geological backgrounds, and geomorphic landscapes. The background values of Cu are strongly spatial heterogeneous. The distributions of predicted Cu background values by random forest regression algorithm are similar to the distribution characteristics of Cu in stream sediments and rocks. The influence of tectonic units on the spatial variations of Cu geochemical background was greatest, followed by geological background, the influence of geomorphic landscape was smallest. The geochemical anomalies drawn by the residuals produced in random forest regression are in good agreement with the known deposits, indicating that the predicted geochemical background of Cu is reasonable and accurate, and has certain theoretical and practical significance.

The China Geochemical Baseline (CGB) project (2008–2012) obtained comparable, continental-scale, geochemical data including lead (Pb) concentrations in the pedosphere. Some 3382 topsoil samples were collected at depths of 0–25 cm. Lead concentrations in soil were determined by inductively coupled plasma mass spectrometry (ICP-MS) using 4-acid extraction under strict quality control. The median Pb concentration throughout China was 22.1 mg/kg and varied between 15.6 and 30 mg/kg according to the morphological landscape. There were predominantly low Pb concentrations in northwestern China and much higher concentrations in southeastern China. This is mainly due to differences in climate and landscape, geology (parent rocks) and the presence of mineralization. The arid and semi-arid landforms in northern and northwestern China had low Pb concentrations. High Pb concentrations were most often linked to geology (occurrence of granite) and climate. The most important Pb anomalies occurred in the southern and southwestern parts of China in areas with known polymetallic mineralization. Such anomalies may be further enhanced by mining or smelting activities.

There are many Late Triassic mafic–ultramafic intrusions in the Hongqiling magmatic Ni–Cu sulfide deposit, Northeast China. Research on magma evolution leading to formation of these mafic–ultramafic intrusions is of great significance for understanding the mantle beneath Northeast China and associated Ni–Cu mineralization. A trace element study of the No. 1, 3, and 7 intrusions in the Hongqiling deposit reveals that these mafic–ultramafic intrusions are characterized by enrichment of incompatible elements, which however cannot be interpreted by subduction modification. Furthermore, model of batch partial melting of depleted mantle accompanied by upper crustal contamination can simulate the trace element patterns of these mafic–ultramafic intrusions, but partial melting of depleted mantle accompanied by lower crustal contamination model cannot work. In addition, Sr–Nd isotopic compositions of the Hongqiling No. 1, 3, and 7 intrusions also indicate that crustal contamination could have occurred mainly during the magma ascent. Consequently, a possible scenario for the magma evolution is that the primary mafic–ultramafic magma was derived from batch partial melting of a depleted mantle, and then contaminated by Cambrian–Ordovician metamorphic rocks of the Hulan Group during ascent. We conclude that the mantle source contained no significant crustal component in the Late Triassic and was also independent of substantial contribution from subducted material, and therefore the Mesozoic large-scale lithospheric delamination beneath eastern China may happen after a period of time of the Late Triassic.

Based on the data of China Geochemical Baselines project, geostatistical analysis was used to investigate the spatial variations in soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents across the “Three Rivers” regions of southwest China, and the factors affecting them were analyzed by the redundancy analysis (RDA) and Person's correlation. Results showed that, the average content of SOC, TN and TP in the study area were 7.20 g/kg, 0.84 g/kg and 0.55 g/kg, respectively. The SOC and TN contents showed an obvious enrichment characteristic with great spatial variability, while TP content was stable on regional scale. The SOC, TN and TP contents decreased with elevation increase in the northern frigid highland, but showed an opposite character in the southern tropical & subtropical, which actually reflected the control of temperature on them. Combined with that there were higher SOC, TN and TP contents in subalpine meadow soil and red earth–yellow earth of the middle latitude zone, these suggested that the suitable temperature was conducive to the accumulation of soil nutrients. The weak positive correlation between population density and soil nutrients, together with high level of soil nutrients in the vicinity of large cities, demonstrated that human activities had significantly increased the soil nutrients contents in the study area. The RDA results showed that soil nutrients in the northern frigid highland were mainly controlled by the environmental factors dominated by temperature and soil structural factors dominated by parent materials with the total explanatory power as high as 75.87%, while in the southern tropical & subtropical mainly by the environmental factors dominated by chemical and biological weathering and the biological factors dominated by vegetation with the total explanatory power as high as 88.53%. The above factors superimposing a certain degree of human activities converged to cause that the SOC and TP contents in the south were higher than that in the north while the TN content was lower than that in the north.

This paper proposes using a simulated annealing (SA) calculation to perform one-dimensional inversion of Geomagnetic Depth Sounding (GDS) to obtain the conductivity information of the lower mantle beneath the Tarim area, to calculate the temperature of the lower mantle according to the relevant formula of the petrophysical experiment, and to provide evidence of the existence of the Tarim mantle plume. The data used for inversion originate from the China Geomagnetic Network Center. This article uses theoretical data to prove that the simulated annealing algorithm can invert the true conductivity model when the data do not contain noise. However, when the data contain noise, it is more accurate to use the statistical expected value of the high-quality conductivity model during the simulated annealing inversion process as the optimal conductivity model rather than the classic simulated annealing algorithm. The simulated annealing inversion results of only four stations in Tarim area show that the conductivity of the top of the lower mantle and the upper part of the mantle transition zone in Tarim area is higher than the global average, and it is speculated that the temperature is 150k&ndash, 450k higher than the global average. This is important evidence for the existence of the mantle plume beneath the Tarim Basin.

The objective of this work was to perform preliminary assessment of the performance of different models for the simulation of three main phenology stages (budburst, flowering, and veraison) of grapevine in China. This work utilized observations from five representative wine regions (Changli, Laixi, Shangri-La, Xiaxian, and Yanqi) and four widely cultivated grape cultivars (Cabernet Sauvignon, Cabernet Franc, Merlot, and Chardonnay) in China. The corresponding daily temperature data were used to simulate the timing of grape phenology stages based on the different phenological models. The dates based on the simulation and the actual dates were compared and the performance of these models were assessed for different cultivars and wine regions. The GDD10 model exhibited the best performance for budburst simulation in soil-burying regions, irrespective of the cultivar and location. For flowering and veraison, the optimal model varied in performance between cultivars and locations, and non-linear models exhibited better performance than linear models. In general, the performance of these models was better for the latter two stages than for budburst. The models with relatively good performance were selected for further calibration using these limited Chinese observations. The impact of soil-burying management on budburst simulation was also estimated. These results highlight the strengths of some phenological models for use in China. This study also reiterates the strong need for establishment of a grapevine phenology observation network in China to obtain more comprehensive data.