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The early Cambrian period is a critical time in Earth's history, marked by the second oxygenation of the atmosphere (known as the Neoproterozoic Oxidation Event) and the rapid evolution of animals, as well as the worldwide large-scale deposits. Polymetallic Ni-Mo deposits have been previously reported in the black rocks at the base of the Cambrian strata on the Yangtze Block, South China, while their genesis is still controversial, and their global occurrences are uncertain. Therefore, we conduct a comprehensive analysis of trace elements and rare earth elements in the black rocks at the base of the Yurtus Formation in the Sugaitblak section (SGT) in Aksu, Tarim Block, and then make a comprehensive study by combining our and other data from the Tarim and Yangtze Block. The distribution patterns of the trace and rare earth element data from our study and another two sections in the Aksu area have shown that the black rocks in the Tarim were strongly enriched in V, Sr, Mo, Ba, and U, moderately enriched in Zn, Cu, Cr, and Pb, and slightly depleted in Ni, and Co during the early Cambrian. These enriched elements could mainly originate from the waning hydrothermal fluids, and then precipitate and preserve in sediments under anoxic environment. The comparison of trace elements in the black rocks between the Tarim and the Yangtze Block suggests that the types of enriched metal elements in these two regions were different, and metal concentrations in the Yangtze Block were much higher than those in the Tarim by 1-3 orders of magnitude. This result indicates that there are no polymetallic Ni-Mo enrichment layers in the black rocks in the Tarim during the early Cambrian, and the widespread polymetallic Ni-Mo enrichments in South China have been more likely influenced by the local hydrothermal activity. It could be further speculated that the early Cambrian period may have been an active period for seafloor hydrothermal activity, with locally different chemical components in hydrothermal fluids. Abundant metal nutrients brought by these hydrothermal activities may have been a potential factor for the rapid evolution of life during this period. [ABSTRACT FROM AUTHOR]

Global climate change is becoming an increasingly serious issue. China, the largest carbon emitter, has a long way towards its sustainable development goals (SDGs) and take on its carbon reduction responsibility, especially in the industrial sector. In this vein, industrial intelligence, a key driver in the "Industry 4.0 era", offers an opportunity in this carbon reduction campaign. This paper seeks to examine the influences of industrial intelligence on carbon emissions, their heterogeneous characteristics and transmission mechanisms, and the moderating role of human capital. Therefore, we properly probed theoretical aspects, and then we used China's provincial data from 2006 to 2019 and a number of tests, namely the fixed effect model, the two‐stage test, and the moderating effect model, to test the relevant assumptions. We first unfolded that industrial intelligence can significantly mitigate carbon emissions. Specifically, the heterogeneous analysis found that carbon reduction efforts are more pronounced in China's central and western regions and resource‐based regions. We further highlight the mechanism identification, which reveals that industrial structure upgrading and technological innovation are the main channels for industrial intelligence to abate CO2 emissions. Importantly, we pinpoint the role of human capital, which positively moderates the relationship between industrial intelligence and carbon emissions and can well amplify the industrial structure effect of industrial intelligence. These results are conducive to accurately assessing the environmental benefits of industrial intelligence and providing policy enlightenment for China to alleviate carbon emissions, and they will also offer a reference for other developing countries to learn from. [ABSTRACT FROM AUTHOR]

Ultra-deep crude oils have become one of the most important targets for petroleum exploration. In ultra-deep petroleum systems, differential hydrocarbon generation of various source rocks and multistage oil accumulation and secondary alteration processes led to the coexistence of crude oils with diverse sources and formation mechanisms. How to effectively identify complicated crude oil categories is a difficult issue confronted with ultra-deep petroleum exploration. Because crude oils are generally fluorescent, fluorescence analysis methods exhibit great application potential for classifying ultra-deep crude oils. However, due to the lack of other restrictive parameters, previous methods based on fluorescence color and fluorescence spectra limit the geological application of fluorescence analysis methods in ultra-deep petroleum systems. Based on the combination of fluorescence spectral parameters and fluorescence lifetimes, this study innovatively provides a new fluorescence analysis method for identifying complex crude oil categories in ultra-deep petroleum systems. Moreover, the sources and formation mechanisms of the ultra-deep crude oil can be further identified by combining fluorescence parameters with physical and geochemical parameters. By applying the above method, this study effectively identified three categories of crude oils and revealed their sources and formation mechanisms in the ultra-deep petroleum system of the southwestern Tabei Uplift, Tarim Basin, China. The new fluorescence analysis method may have practical significance for revealing the sources and formation mechanisms of ultra-deep crude oils. • The new fluorescence method can effectively classify ultra-deep crude oil categories. • The fluorescence characteristics of biodegraded and non-biodegraded oils are diverse. • Fluorescence parameters can be used for direct reservoir and inclusion oil correlation. • Three categories of crude oils are identified in the southwestern Tabei Uplift. [ABSTRACT FROM AUTHOR]

• Organic petrology and biomarkers in the Lower Cretaceous Jiufotang Formation from the Kazuo Basin were investigated. • Terrigenous organic matter was diluted by detrital minerals and phytoplankton was the most important organic matter source. • Anoxic bottom water may be necessary for organic matter enrichment in lake systems. • Climate changes controlled the organic matter enrichment model during deposition of the Jiufotang Formation. The Lower Cretaceous Jiufotang Formation, situated in western Liaoning Province, China, has attracted attention for abundant Jehol Biota fossils and the potential to improve understanding of the relationships among climate change, evolution of terrigenous organisms, and organic matter (OM) enrichment in lake systems during the Early Cretaceous. Based on organic petrology and biomarker analyses, this study investigated the depositional environment, OM sources, and enrichment mechanism of Jiufotang mudstone in the Kazuo Basin. Maceral composition shows that the OM source of Jiufotang mudstone shifted from mainly aquatic to terrigenous, and biomarkers such as abundant diterpenoids and retene indicate that terrigenous higher plants were mainly conifers during deposition of the Jiufotang Formation. Pr/Ph ratios (0.07–0.65) show that the studied section was deposited in anoxic bottom water that may be necessary for OM enrichment in lake systems. Gravity flows were accompanied by input of many clastic minerals and oxygenation of bottom waters, which is unfavorable for OM enrichment. Therefore, the best OM enrichment model for lake systems includes anoxic bottom water, stable water column stratification, low sedimentation rates, and high phytoplankton contributions. The climate changed from relatively dry to humid, which drove changes in the OM enrichment model in the lake. More importantly, the climate and terrigenous plant information obtained by biomarkers is useful to reconstruct the ecological environment of the Jehol Biota. [ABSTRACT FROM AUTHOR]