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The newly discovered Baogudi gold district is located in the southwestern Guizhou Province, China, where there are numerous Carlin-type gold deposits. To better understand the geological and geochemical characteristics of the Baogudi gold district, we carried out petrographic observations, elemental analyses, and fluid inclusion and isotopic composition studies. We also compared the results with those of typical Carlin-type gold deposits in southwestern Guizhou. Three mineralization stages, namely, the sedimentation diagenesis, hydrothermal (main-ore and late-ore substages), and supergene stages, were identified based on field and petrographic observations. The main-ore and late-ore stages correspond to Au and Sb mineralization, respectively, which are similar to typical Carlin-type mineralization. The mass transfer associated with alteration and mineralization shows that a significant amount of Au, As, Sb, Hg, Tl, Mo, and S were added to mineralized rocks during the main-ore stage. Remarkably, arsenic, Sb, and S were added to the mineralized rocks during the late-ore stage. Element migration indicates that the sulfidation process was responsible for ore formation. Four types of fluid inclusions were identified in ore-related quartz and fluorite. The main-ore stage fluids are characterized by an H2O–NaCl–CO2–CH4 ± N2 system, with medium to low temperatures (180–260 °C) and low salinity (0–9.08% NaCl equivalent). The late-ore stage fluids featured H2O–NaCl ± CO2 ± CH4, with low temperature (120–200 °C) and low salinity (0–7.48% NaCl equivalent). The temperature, salinity, and CO2 and CH4 concentrations of ore-forming fluids decreased from the main-ore stage to the late-ore stage. The calculated δ13C, δD, and δ18O values of the ore-forming fluids range from − 14.3 to − 7.0‰, −76 to −55.7‰, and 4.5–15.0‰, respectively. Late-ore-stage stibnite had δ34S values ranging from − 0.6 to 1.9‰. These stable isotopic compositions indicate that the ore-forming fluids originated mainly from deep magmatic hydrothermal fluids, with minor contributions from strata. Collectively, the Baogudi metallogenic district has geological and geochemical characteristics that are typical of Carlin-type gold deposits in southwest Guizhou. It is likely that the Baogudi gold district, together with other Carlin-type gold deposits in southwestern Guizhou, was formed in response to a single widespread metallogenic event. [ABSTRACT FROM AUTHOR]

The present study aims to explore the effects of grandiose and vulnerable narcissism on emotion dysregulation and examine the mediating role of self-esteem on these associations. Undergraduates (N = 426) completed self-report measurements on grandiose narcissism, vulnerable narcissism, self-esteem and emotion dysregulation. Correlation analyses indicated that grandiose narcissism was negatively correlated with emotion dysregulation, while vulnerable narcissism was positively correlated with emotion dysregulation. Moreover, mediational analyses revealed that self-esteem fully mediated the association between grandiose narcissism and emotion dysregulation, and partially mediated the association between vulnerable narcissism and emotion dysregulation. The present study highlights the importance of selfesteem and deepens the understanding of the associations between the two forms of narcissism and emotion dysregulation. [ABSTRACT FROM AUTHOR]

The Shuiyindong Gold Mine hosts one of the largest and highest-grade, strata-bound Carlin-type gold deposits discovered to date in Southwestern China. The outcrop stratigraphy and drill core data of the deposit reveal Middle–Upper Permian and Lower Triassic formations. The ore is mainly hosted in Upper Permian bioclastic limestone near the axis of an anticline. The gold is mainly hosted in arsenian pyrite and arsenopyrite, mainly existing in the form of crystal lattice gold, submicroscopic particles and nanoparticles. Fluorite commonly occurs at the vicinity of an unconformity between the Middle–Upper Permian formations, which is proposed to be the structural conduit that fed the ore fluids. Calcite commonly fills fractures at the periphery of decarbonated rocks, which contain high grade orebodies. This study aimed to verify the occurrence of two distinct hydrothermal events at the Shuiyindong, based on Sm–Nd isotope dating of the fluorite and calcite. For this purpose, rare-earth element (REE) concentrations, Sm/Nd isotope ratios, and Sm–Nd isochron ages of the fluorite and calcite were determined. The fluorite and calcite contain relatively high total concentrations of REE (12.3–25.6 μg/g and 5.71–31.7 μg/g, respectively), exhibit variable Sm/Nd ratios (0.52–1.03 and 0.57–1.71, respectively), and yield Sm–Nd isochron ages of 200.1 ± 8.6 Ma and 150.2 ± 2.2 Ma, with slightly different initial ε Nd (t) values of −4.4 and −1.1, respectively. These two groups of Sm–Nd isochron ages suggest two episodes of hydrothermal events at the Shuiyindong gold deposit. The age of the calcite probably represents the late stage of the gold mineralization period. The initial ε Nd (t) values of the fluorite and calcite indicate that the Nd was probably derived from mixtures of basaltic volcanic tuff and bioclastic limestone from the Permian formations. [ABSTRACT FROM AUTHOR]

This study seeks to provide a basic approach to fulfill the spatial visualization of geopolitical environmental factors required for the navigation of vessels in the Arctic. Multi-dimensional geopolitical environmental factors of the Arctic Passage are analyzed and classified into geopolitics, geoeconomics, geo-military, geoculture, and laws and regulations related to geography. Their characteristics are extracted to form an attribute information table matching spatial layers. Based on the information category and basic characteristics, the spatial match method is applied and connected with the spatial layers to examine the spatial point, polyline, and polygon. According to the qualitative description, the study extracted the quantitative indicators for the following spatial-temporal pattern analysis. The standard deviational ellipse is used to analyze the spatial-temporal patterns and trends of the geopolitical environmental indicators of the Arctic Passage in the Arctic and Northeast Asia. The expansion and contraction of geoinformation coexist in the countries surrounding the Arctic Passage. The spatial-temporal changes indicate that the Arctic channel has a great economic impact on the Nordic countries and Northeast Asia, especially the coastal areas of China and Japan. The characteristic extraction and spatial match of the geopolitical environment provide integrated Arctic geoinformation inquiry and services for the diplomatic, administrative, and legal preparations required for Arctic navigation. Therefore, the geospatial analysis conducted provides scientific support and a basis for the geographical distribution and developing trends of visualization and spatial-temporal pattern in Arctic navigation. The results of this research will help decision-makers to make a comprehensive judgment on governance related to the sustainable development of the Arctic Passage., Competing Interests: The authors have declared that no competing interests exist.