Despite the growing concern regarding post-mineralization thermo-tectonic processes in recent years, the relative roles in exhuming and preserving ore deposits remain highly controversial. This study presents new apatite fission track and (U-Th)/He data from the Xishimen iron skarn deposit in the Handan-Xingtai district, central North China Craton. Apatite fission track dating yielded central ages ranging from 88 ± 18 Ma to 125 ± 9 Ma, with mean confined track lengths varying between 11.9 ± 0.4 μm and 13.3 ± 0.2 μm. Integrated apatite (U-Th)/He dating provided ages of 42.5 ± 0.8 Ma to 48.1 ± 3.3 Ma. Our new data, combined with previous zircon U-Pb and potassium-bearing mineral 40Ar/39Ar ages, revealed three cooling episodes: very rapid cooling (100–140 °C/Ma) at ca. 130–120 Ma, a protracted slow cooling period (0.2–0.4 °C/Ma) at ca. 120–50 Ma, and moderate cooling (0.8–1.0 °C/Ma) since ca. 50 Ma. The initial rapid cooling phase was primarily attributed to post-magmatic thermal equilibration following the shallow emplacement of the Xishimen deposit. The subsequent cooling phases were controlled by uplift and exhumation processes. Our thermal models indicate an estimated total unroofing thickness of < 3 km, which is shallower than the emplacement depth of the ore deposit (3–5 km). This suggests significant potential for mineral exploration. Furthermore, a comprehensive review of preservation mechanisms for various ore deposits underscores the significant role of tectonics in both exhuming and preserving ore bodies.
Understanding the tectono-magmatic evolution history of the Tengchong block is crucial for elucidating the formation of the Eastern Tethys tectonic domain. However, the correlation and evolution of the Tengchong block with the Sibumasu and Lhasa blocks is controversial during the Permian and Cretaceous. This study explores the information contained within magmatic rocks using big data and spatio-temporal analysis, providing quantitative constraints for the discussion of the tectono-magmatic evolution of the Tengchong block. To more accurately assess true magma activities and reduce errors caused by preservation and sampling processes, we utilized local singularity analysis to obtain the singularity index time-series. Correlation analysis of zircon ages and εHf(t) (correlation coefficient ≥ 0.5) values indicates that the Tengchong block is more similar to the Sibumasu block. Results from time-lagged cross-correlation analysis indicate that the Tengchong block and Sibumasu block exhibit a shorter lag in magmatic activities (3 Myr). Wavelet analysis reveals similar periods of collision-related magmatic activities (57 Myr and 43 Myr). Integrating evidence from paleontology and ophiolite belts, we propose that the Tengchong block co-evolved more closely with the Sibumasu block than with the Lhasa block, suggesting similar tectonic processes during the Early Permian to Early Cretaceous. Approximately 250–236 Ma, in the western Tengchong block, partial melting of the lower crust occurs due to crustal thickening. Around 219–213 Ma and 198–180 Ma, after the Tengchong block collided with the Eurasian continent, the subduction of the Meso-Tethys Ocean commenced. Around 130–111 Ma, the overall tectonic feature was a scissor-like closure of the Meso-Tethys Ocean from north to south.
Shale gas is being hailed as the green energy of the future due to high heating value, low carbon emissions, and large reserves. Gas content of shale is a key parameter for evaluating the shale gas potential and screening for the shale gas sweet spots. Although the concept of gas content has been well defined, obtaining a reliable gas content data still remains a challenge. A significant barrier is the method for evaluating the gas content. In this paper, we provide a review of the long-established and recently developed gas content evaluation methods. In the first part of this review article, the history of gas content evaluation methods is summarized since 1910s, relied on published and unpublished literatures as well as our own experiences. Then, the fundamental contents and concepts involved in gas content evaluation are introduced to provide a clear theoretical foundation for the methods. In the third part, eleven evaluation methods, including four direct methods and seven indirect methods, are systematically reviewed. In each method, its application to evaluating the gas content is presented, the key advances are highlighted, and the advantages and limitations are discussed. Finally, future directions are discussed to promote creative thinking across disciplines to develop new methods or improve current methods for evaluating the gas content more accurately and efficiently.
Understanding the intricate relationships between the solid Earth and its surface systems in deep time necessitates comprehensive full-plate tectonic reconstructions that include evolving plate boundaries and oceanic plates. In particular, a tectonic reconstruction that spans multiple supercontinent cycles is important to understand the long-term evolution of Earth’s interior, surface environments and mineral resources. Here, we present a new full-plate tectonic reconstruction from 1.8 Ga to present that combines and refines three published models: one full-plate tectonic model spanning 1 Ga to present and two continental-drift models focused on the late Paleoproterozoic to Mesoproterozoic eras. Our model is constrained by geological and geophysical data, and presented as a relative plate motion model in a paleomagnetic reference frame. The model encompasses three supercontinents, Nuna (Columbia), Rodinia, and Gondwana/Pangea, and more than two complete supercontinent cycles, covering ∼40% of the Earth’s history. Our refinements to the base models are focused on times before 1.0 Ga, with minor changes for the Neoproterozoic. For times between 1.8 Ga and 1.0 Ga, the root mean square speeds for all plates generally range between 4 cm/yr and 7 cm/yr (despite short-term fast motion around 1.1 Ga), which are kinematically consistent with post-Pangean plate tectonic constraints. The time span of the existence of Nuna is updated to between 1.6 Ga (1.65 Ga in the base model) and 1.46 Ga based on geological and paleomagnetic data. We follow the base models to leave Amazonia/West Africa separate from Nuna (as well as Western Australia, which only collides with the remnants of Nuna after initial break-up), and South China/India separate from Rodinia. Contrary to the concept of a “boring billion”, our model reveals a dynamic geological history between 1.8 Ga and 0.8 Ga, characterized by supercontinent assembly and breakup, and continuous accretion events. The model is publicly accessible, providing a framework for future refinements and facilitating deep time studies of Earth’s system. We suggest that the model can serve as a valuable working hypothesis, laying the groundwork for future hypothesis testing.
Climate change is the most phenomenal challenge to humanity, and its roots are intervened with unsustainable industrialization, exercising overexploitation of natural resources. Therefore, the departure from non-renewable to renewables has become inevitable, though thought-provoking. In this respect, we explore how green energy transformation moderates the impacts of multifaceted natural resources on sustainable industrial development in the presence of other covariates involving technological progress, financial development, and economic progress. We compiled data from Group of Seven (G-7) members over the 1995−2018 period and applied panel quantile regression (PQREG) to capture the effects across varying levels of quantiles of sustainable industrial development. Results revealed a positive role of natural gas rents, while coal, forest, and total natural resource rents contributed adverse implications for sustainable industrial development. However, the green energy transformation proved to be the game changer because it not only directly induced sustainable industrial development improvement but also turned the unfavorable effects of coal, forest, and total natural resources into favorable ones by interacting with those multifaceted natural resources. Technological, financial, and economic progress supported sustainable industrial development in G-7 nations, particularly in members with existing middle and upper scales of sustainable industrial development. These findings are robust enough when subjected to different estimation tools. In light of these outcomes, the interaction between green energy transformation and natural resource policy is inevitably critical to attaining natural resource efficiency for sustainable industrial development. Therefore, it is imperative to establish a close policy coordination between advancing green energy technology and allocating natural resource revenue to achieve sustainable development goals (SDGs), with a particular emphasis on SDG-7 and SDG-13.
Reliability analysis plays an important role in the risk management of geotechnical engineering. For the random field-based method, it is expected that the uncertainty characterization of geo-material parameters and the realization of random field can be integrated effectively. Moreover, as the increase in measured data size is generally difficult in the field investigation of geotechnical engineering due to limitation of budget and time etc., the statistical uncertainty resulting from sparse data should be paid great attention. Therefore, taking the determination of hyper-parameters for Bayesian-based conditional random field as the breakthrough, this study proposed a reliability analysis framework to achieve the expectation above. In this proposed reliability analysis framework, the present characterization method of statistical uncertainty is improved by setting the lognormal distribution as the prior distribution of scale of fluctuation (SOF). Subsequently, the performance of statistical uncertainty characterization method is tested by a set of unconfined compressive strength (UCS) database about rocks. Then, a case study about the stability analysis of slope is employed to demonstrate the beneficial effect of the proposed reliability analysis framework. It is found that the uncertainty in both the realization of random field and the reliability analysis results can be significantly mitigated by the proposed reliability analysis framework.
In a paper in 1970, Brian Windley first recognised that early terrestrial and lunar anorthosites both have calcic plagioclase, and low TiO2 and high CaO and Al2O3 contents. Despite these similarities, the geochemistry of early terrestrial and lunar anorthosites has not been rigorously compared and contrasted. To this end, we compiled 425 analyses from 212 early terrestrial anorthosite occurrences and 306 analyses from 16 lunar anorthosite occurrences. This was supplemented by a compilation of plagioclase anorthite (An) contents and pyroxene Mg# from early terrestrial and lunar anorthosites. Early terrestrial anorthosites have lower whole-rock An contents but similar Mg# to lunar anorthosites. The CaO contents of lunar anorthosites are higher than those of early terrestrial anorthosites for a given MgO and Al2O3 content, early terrestrial anorthosites have higher SiO2 contents than lunar anorthosites at a given MgO content, and lunar anorthosites have higher Eu/Eu* anomaly ratios yet broadly similar La/Yb and Nd/Sm ratios than early terrestrial anorthosites. Some early terrestrial anorthosites have less fractionated chondrite-normalised rare earth element (REE) patterns and less prominent positive Eu anomalies than lunar anorthosites. Lunar anorthosites have higher plagioclase An contents, yet a similar range of pyroxene Mg# compared to their early terrestrial counterparts. Some early terrestrial anorthosites are more fractionated than some lunar anorthosites. Our interpretations imply that most early terrestrial anorthosites crystallised from basaltic parental magmas that were generated by high-degree partial melting of sub-arc asthenosphere mantle wedge sources that were hydrated by slab-derived fluids, with the remainder being associated with mid-ocean ridge and mantle plume settings. Some of the arc-related early terrestrial anorthosites were influenced by crustal contamination. In addition, early terrestrial anorthosites originated from partial melting of the mantle at various depths with variable garnet residua, whereas lunar anorthosites formed without any significant garnet residua. Lower plagioclase CaO contents and pyroxene Mg# in early terrestrial anorthosites can be explained by higher proportions of clinopyroxene and olivine fractionation in terrestrial magma chambers than in the lunar magma ocean where orthopyroxene and olivine fractionation occurred. Low TiO2 contents in both terrestrial and lunar anorthosites reflect rutile and/or ilmenite fractionation.
Water temperature is a critical indicator and weathervane of aquatic ecosystems. However, the vast majority of rivers lack long-term continuous and complete water temperature datasets. In this study, ensemble models by combining NARX (nonlinear autoregressive network with exogenous inputs) and air2stream were used to reconstruct daily river water temperatures for 27 hydrological stations in the Odra River Basin, one of the largest river systems in Europe. For each hydrological station, both the NARX and air2stream models were calibrated and validated, and the better-performed model was selected to reconstruct daily river water temperatures from 1985 to 2022. The results showed that hybrid modeling by combining NARX and air2stream is promising for reconstructing daily river water temperatures. Based on the reconstructed dataset, annual and seasonal trends of water temperature and characteristics of river heatwaves were evaluated. The results indicated that annual river water temperatures showed a consistent warming trend over the past 40 years with an average warming rate of 0.315 °C/decade. Seasonal river water temperatures indicated that summer warms faster, followed by autumn and spring, and winter river water temperatures showed an insignificant warming trend. River heatwaves are increased in frequency, duration, and intensity in the Odra River Basin, and 6 out of 27 hydrological stations have river heatwaves categorized as ‘severe’ and ‘extreme’, suggesting that mitigation measures are needed to reduce the impact of climate warming on aquatic systems. Moreover, results showed that air temperature is the major controller of river heatwaves, and river heatwaves tend to intensify with the warming of air temperatures.
The phenomenon of carbon isotopic fractionation, induced by the transport of methane in tight sedimentary rocks through processes primarily involving diffusion and adsorption/desorption, is ubiquitous in nature and plays a significant role in numerous geological and geochemical systems. Consequently, understanding the mechanisms of transport-induced carbon isotopic fractionation both theoretically and experimentally is of considerable scientific importance. However, previous experimental studies have observed carbon isotope fractionation phenomena that are entirely distinct, and even exhibit opposing characteristics. At present, there is a lack of a convincing mechanistic explanation and valid numerical model for this discrepancy. Here, we performed gas transport experiments under different gas pressures (1–5 MPa) and confining pressures (10–20 MPa). The results show that methane carbon isotope fractionation during natural gas transport through shale is controlled by its pore structure and evolves regularly with increasing effective stress. Compared with the carbon isotopic composition of the source gas, the initial effluent methane is predominantly depleted in 13C, but occasionally exhibits 13C enrichment. The carbon isotopic composition of effluent methane converges to that of the source gas as mass transport reaches a steady state. The evolution patterns of the isotope fractionation curve, transitioning from the initial non-steady state to the final steady state, can be categorized into five distinct types. The combined effect of multi-level transport channels offers the most compelling mechanistic explanation for the observed evolution patterns and their interconversion. Numerical simulation studies demonstrate that existing models, including the Rayleigh model, the diffusion model, and the coupled diffusion-adsorption/desorption model, are unable to describe the observed complex isotope fractionation behavior. In contrast, the multi-scale multi-mechanism coupled model developed herein, incorporating diffusion and adsorption/desorption across multi-level transport channels, effectively reproduces all the observed fractionation patterns and supports the mechanistic rationale for the combined effect. Finally, the potential carbon isotopic fractionation resulting from natural gas transport in/through porous media and its geological implications are discussed in several hypothetical scenarios combining numerical simulations. These findings highlight the limitations of carbon isotopic parameters for determining the origin and maturity of natural gas, and underscore their potential in identifying greenhouse gas leaks and tracing sources.
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