Placing cratons, orogens, terranes, and igneous whole-rock U-Pb zircon samples in their past positions within paleogeographic reconstructions provides insight into global geodynamics, enables testing of reconstruction models, and stimulates new hypotheses. We integrated these data with recent full-plate paleogeographic reconstructions spanning 1800–0 Ma. Their temporal and paleogeographic distribution: (1) indicates a strong correlation between zircons associated with convergent margins and subduction zones; (2) are consistent with the supercontinent cycle; and (3) generally supports (with some exceptions) the adopted paleogeographic model. We also propose a new “continent-only” global paleogeographic animation for 2000–1800 Ma.
The lunar surface is characterized by extreme temperature variations and intense space weathering, which continuously shape the physical and mechanical properties of lunar regolith. However, the micro-mechanical response of authentic lunar particles under extreme thermal environments remains largely unexplored. This study investigates the mechanical properties of Chang’e-5 lunar regolith between −120 ℃ and 130 ℃. The lunar regolith mainly consists of five categories: plagioclase, pyroxene, olivine, ilmenite, and glass. Raman spectroscopy and particle identification were initially applied to identify these five samples. High- and low-temperature nanoindentation tests were then conducted to measure mechanical properties. The results reveal that all particles exhibit a continuous, monotonic temperature-dependent mechanical response governed by Arrhenius-type thermal activation, displaying continuous thermal softening at elevated temperatures up to 130 °C and pronounced thermal strengthening down to −120 °C relative to ambient conditions (20 °C). By comparing the mechanical responses of lunar and terrestrial counterparts across extreme temperatures, the observed property divergence is found to be consistent with potential space-weathering effects, providing insights into the physical evolution of lunar regolith. Finally, the significance of these findings for the engineering implications for lunar base construction and ISRU are discussed.
South Africa is recorded as the largest anthropogenic carbon emitter on the African continent. A large portion of these emissions are linked to the country’s reliance on coal for energy generation and socioeconomic development. The South African Government has committed to reducing the country’s carbon emissions by at least half over the next ten years. The complexity of South Africa’s coal-climate economy implies that the country will reduce emissions within a Just Transition framework. This means that coal will still feature prominently within this period. Carbon Capture, Utilisation and Storage (CCUS) provides a potential pathway to support South Africa’s climate change goals while advancing the intended Just Transition. The success of CCUS technologies depends significantly on suitable geological storage reservoirs, deployment costs, and associated economic incentives. This paper contributes to this body of knowledge by presenting findings from integrated geoscience research of a proposed CCUS site in the Govan Mbeki Municipality in the Mpumalanga Province. These findings draw on newly reported geoscience data from regional geological and structural mapping, airborne geophysics, 3D reflection seismics, mineralogy, petrography, and geochemistry. Volumetric estimates suggest that the basalt sequences alone may store at least 1× 106 t of carbon dioxide. The contiguous nature of the geology across much of northern South Africa implies substantial additional underground storage potential. These reservoirs are also located proximal to South Africa’s coalfields and major carbon emitters. Economic models are also presented to evaluate the potential role of CCUS within South Africa’s coal-economy-climate change nexus. Under current policy considerations, CCUS adoption may support a coal value chain to at least USD 20 billion per annum by 2050, alongside the production of at least 16×106 GWh of coal-fired power. Successful pilot-scale demonstration is, however, imperative. South Africa should focus on the deployment of pilot-scale CCUS technologies to validate reservoir performance and support a sustainable Just Transition.
The geochemical and mineralogical composition of sedimentary rocks from the Talchir, Barakar, and Motur formations of the Wardha Basin, Pranhita-Godavari Rift Valley, Peninsular India, was investigated to constrain the late Carboniferous to early Permian chemical weathering responses during post-glacial warming. The objective is to document climatic and environmental changes during deglaciation in mid- to high-latitude regions of Gondwana. Provenance analysis indicates granitic sources for the Talchir Formation, with a transition toward metamorphic-mafic (granite-gneissic) input in the Barakar and Motur formations. Geochemical indices reveal persistent low-to-moderate chemical weathering in the Talchir interval and moderate weathering in the Barakar and Motur intervals, suggesting a predominantly cold-to-semiarid climate in the source region. Stratigraphic comparison with the Satpura Basin, the terminal depocenter of the Pranhita-Godavari Rift, reveals contrasting paleoclimate conditions: the Wardha Basin remained relatively colder and drier, whereas the Satpura Basin experienced a warmer, more humid climate. These regional contrasts reveal spatial variability in Gondwanan climatic responses during the late Paleozoic. The results indicate that late Paleozoic climate change in Gondwana was gradual and spatially heterogeneous, with relatively persistent cold conditions in high- to mid-latitude basins sustained by upland glaciation through the Permian. The correlations among the Gondwana Basins suggest that both regional paleotopography and global forcing factors together drove the late Paleozoic climate transition.
Lacustrine shale oil has become an increasingly important contributor to oil supply in China, yet its enrichment mechanisms remain more difficult to generalize than those of marine shale systems because of stronger heterogeneity, more variable organic matter inputs, and wider maturity ranges. Although numerous case studies have investigated the factors controlling shale oil enrichment, existing strategies for evaluating potential targets still rely heavily on empirically selected parameters (such as TOC content, S1 value, and OSI ratio) and basin-specific experience. As a result, a conceptual screening framework for evaluating potential targets in lacustrine shale oil systems remains insufficiently developed. This study synthesizes current knowledge of lacustrine shale oil systems in China and establishes an integrated framework for understanding their enrichment mechanisms. Four controlling factors are identified: hydrocarbon generation, storage capacity, preservation conditions, and fracability coupled with dynamic enrichment (fluid properties and oil mobility). Correspondingly, the key geological and geochemical proxies used in potential target evaluation are systematically summarized, and their geological significance, applicability, and limitations are clarified. On this basis, Rock-Eval pyrolysis is further positioned as a practical and cost-effective screening tool, from which an operational workflow is developed to support the rapid identification of potential intervals. Another central contribution of this study is the reinterpretation of Tmax value suppression in shale oil systems, a phenomenon that has traditionally been regarded in conventional petroleum systems as an anomaly that hinders the objective assessment of thermal maturity. Here, we show that, under geological conditions favorable for lacustrine shale oil enrichment, Tmax value suppression may instead serve as a potential screening indicator of oil enrichment and help identify intervals warranting further evaluation. Building on this insight, a four step Tmax value suppression-based workflow for shale oil exploration potential evaluation is proposed: recognition of anomalous Tmax values, data-quality screening, exclusion of kerogen and mineral-related effects using multiple constraints, and cross-checking with complementary parameters. A detailed examination of the Paleogene Shahejie Formation in the Bohai Bay Basin illustrates the potential applicability of this approach, while evidence from three additional lacustrine shale systems in China further supports its potential applicability across different lacustrine settings. This study links enrichment mechanisms, assessment proxies, and operational decision-making within a unified framework for lacustrine shale oil enrichment. The proposed workflow not only refines the geological interpretation of Rock-Eval parameters, but also provides a rapid and practical screening approach that helps identify intervals requiring further geological, geochemical, and engineering evaluation.
