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<jats:p>Following the latest Permian mass extinction (LPME), abundant unusual sedimentary features and fabrics were widely distributed in Early Triassic carbonate platforms. As a unique type of carbonate grain, spheroids from the Lower Triassic are infrequently reported, yet differ significantly from giant ooids and oncoids. Griesbachian micritic spheroids are well preserved in the Lower Triassic Feixianguan Formation at the Baimiaozi (BMZ) outcrop in Beibei, Chongqing, southwestern China. These spheroids (diameter: 3.9–10.8 mm) were in a marl layer interbedded with massive oolites. They were deposited in the wave troughs of ripple marks comprising micritic clots, sparry calcite, clay minerals, organic matter and pyrite. A microbial spheroid origin is implied based on the coccoidal microbes (coccoid‐like microspherules and bacterial clump‐like microspherules), numerous pyrite framboids (indications suggest the presence of many sulphate‐reducing bacteria and the high iron content in seawater can promote nitrogen‐fixing cyanobacteria proliferation) and microbial‐derived microspherules. The dark‐coloured matrix between the spheroids primarily included microcrystalline calcite, clay minerals, organic matter and metazoan fossils. The spherical and ellipsoidal shapes of the spheroids suggested rapid accretion and lithification. As a unique carbonate depositional mode, Greisbachian spheroids may have been recorded for a palaeo‐ocean with dysoxic and calcium carbonate supersaturation shortly after the LPME.</jats:p>

<jats:p>Malan loess possesses unfavourable engineering mechanical properties that may vary depending on the geological context in which it exists. In the context of roadbed loading, the structural characteristics of the loess roadbed often result in uneven settlement, which significantly impacts transportation safety. To investigate the dynamic behaviour of loess under the influence of vehicle loading, groups of dynamic rebound modulus tests were conducted using a dynamic triaxial apparatus. Three key aspects are highlighted: compaction degree, moisture content and stress state. The results reveal that the dynamic rebound modulus of loess tends to increase with higher compaction degrees, decrease with increased moisture content and rise under greater confining pressure. For Maran loess, the water content has the greatest influence on its physical and mechanical properties. Under conditions of a confining pressure of 60 kPa and a deviatoric stress of 30 kPa, as the moisture content increased from <jats:italic>w</jats:italic> = 9% to <jats:italic>w</jats:italic> = 18%, the minimum dynamic rebound modulus decreased by 63%.</jats:p>

<jats:p>Tunnelling in complex geological strata is a challenging task that can affect the performance of shield machines and result in unexpected hazards. Therefore, extensive knowledge of unfavourable environments and shield operational parameters is essential for ensuring successful and safe tunnelling. This study aims to analyse the geological and hydrological conditions of the Chunfeng Tunnel and present the key construction technologies of a large slurry shield machine when crossing complex strata. To this end, attempts were made to (i) discuss the geological and environmental challenges encountered during the tunnelling process and present some early interpretations based on the database information, (ii) analyse the factors affecting tunnel performance and simulate the ground surface settlement along the tunnel alignment and (iii) discuss the countermeasures under adverse ground conditions and propose future directions. The results revealed that tunnelling in fault zones with soft upper and hard lower strata led to severe wear of disc cutters and controlling the tunnelling parameters could provide a suitable method for adjusting the construction process. This study leveraged extensive experience gained during tunnelling using a large slurry shield machine, with special emphasis on mixed ground strata, by providing valuable insights and suggested responses for effective tunnelling strategies.</jats:p>

<jats:p>The Ramagiri greenstone terrane (RGT) of Central Dharwar craton, India, is recognized as remnants of Archean oceanic crust squeezed between ancient proto‐continental terranes. The granites and gneisses formed as a result of partial melting, resisted subduction and collided, sinking the intervening ocean basin. The geochemical characteristics of the bimodal metavolcanics of RGT were carefully assessed using suitable proxy. An insight into them suggests that the mafic rocks bear characteristics of island arc tholeiites belonging to suprasubduction zone setting, as corroborated by their low TiO<jats:sub>2</jats:sub>/Yb (avg 443) and high Th/Nb (avg 0.8). Their high V/Ti (avg 0.3) ratio points towards a mantle source that has been influenced by subduction, whereas low Ti/Yb echoes high degrees of shallow melting with little residual garnet. The felsic rocks on the other hand are metaluminous–peraluminous, mostly calc‐alkaline and geochemically akin to I‐ and S‐type syncollisional and volcanic arc granite emplaced during intercontinent collision. Their immobile element plot with low Nb + Y (avg 25) concentration also points towards a volcanic arc environment.</jats:p>

<jats:p>The Dunhuang Basin, situated in western China along the Altyn Tagh Fault (ATF) zone, intersects the Tethys and Paleo‐Asian Ocean tectonic domains. Influenced by both the ATF system and the far‐field effects of the Qiangtang‐Lhasa‐Eurasia collision during the Mesozoic, the mechanism of the Jurassic sedimentary migration of the basin in response to tectonic movements is unclear so far. The paper uses a comprehensive approach, including field geological surveys, lithologic and lithofacies discern, stratigraphic relationships analysis and 2D seismic profile interpretation, to examine the distribution of Jurassic residual strata in the basin. The comprehensive results of our study suggest that the Dunhuang Basin exists as an isolated block with unique tectonic and sedimentary evolution characteristics. In the Early Jurassic, the Dunhuang Basin underwent initial rifting, leading to the formation of small segmented intermontane sags. This phase was marked by the coarse particle sedimentary system of alluvial fans and braided rivers, represented the near source rapid deposition in the initial formation period of the basin. Stratigraphic distribution was primarily influenced by pre‐Jurassic basement topography and was not significantly constrained by faulting during this period. The formation of these isolated discontinuous small intermontane sags indicates the segmented activities of the ATF in the Early Jurassic period. In the Middle Jurassic period, influenced by the ATF dextral strike‐slip faulting, sedimentation extended eastward and the depocenter migrated clockwise compared with the distribution of the Middle Jurassic strata within the Dunhuang Basin. This period witnessed the development of coal measure strata at the basin's margins and lacustrine fine‐grained clastic deposition in the centre. The segmented fracture of the ATF gradually initiated a unified dextral strike‐slip tectonic movement. In the Late Jurassic period, sedimentary strata were locally present in the Wanyao Sag but absent in other sags. The depocenter migrated counterclockwise compared with the distribution of Middle Jurassic strata within the Dunhuang Basin, due to regional uplift accompanied by the ATF sinistral strike‐slip faulting caused by the collision between the Lhasa Block and the Eurasia Plate. The depocenter migration of the Dunhuang Basin constrained within the ATF system from the Early to Middle and Late Jurassic can be attributed to the transition of the ATF strike‐slip faulting in context of the stress relaxation and compression between the collision of the Qiangtang and Lhasa blocks to the Eurasia Plate, respectively.</jats:p>

<jats:p>Carbon emissions, ecological pollution and a steadily rising global temperature have been widely acknowledged as the most severe risks to human survival in the last few decades. Alarming increases in global temperature and sudden climatic shifts are nature's way of warning us to curb the use of fossil fuels and adopt more sustainable practices. Therefore, the present study investigates the impact of financial stability, environmental regulations and uncertain economic policies on carbon emissions and investment in renewable energy. The study used a nonparametric DEA‐DDF technique to fulfil this objective using a balanced panel dataset comprising 28 Chinese provinces from 2011 to 2021. Overall results demonstrated that financial stability reduces carbon emissions and accelerates investment in renewable energy projects. The findings imply that a financially stable economy like China encourages businesses to invest in cutting‐edge, environmentally friendly technology to boost productivity while reducing carbon emissions. Likewise, results show that stringent ecological regulations decrease carbon emissions and promote investment in renewable energy. Hence, stakeholders are keen to comply with environmental regulations in China to reduce carbon emissions by investing in renewable energy resources to avoid penalties. Finally, results suggest that uncertain economic policies increase carbon emissions and restrict access to credit from financial institutions for investment in renewable energy purposes in China. Findings imply that uncertainty in economic policies could lead to less environmentally friendly production practices that may increase carbon emissions and reduce the demand for renewable energy products.</jats:p>

<jats:p>Large igneous provinces (LIPs) are often the surface expressions of mantle plume process. Intensive magma could occur in the continental crust when a mantle plume penetrates the Moho. How magmas migrate in the crust, forming LIPs, remains debated. In this study, we employ 2D thermo‐mechanical numerical modelling to study the dynamics of magma intrusion and migration within the continental crust affected by a mantle plume. Our results suggest that (1) lateral magma migration dominates crustal deformation, promoting the possible formation of metamorphic core complexes; (2) two distinct crustal deformation modes are recognized regarding the presence or absence of crustal break‐up, affected by whether a significant vertical magma migration occurs; (3) the crustal thickness, Moho temperature and the length of the preset weak crust–mantle decoupling zone are the three key parameters controlling crustal magma migration. This study highlights the importance of lateral magma migration in the lower crust and provides physical mechanisms for the interpretation of magma migration under LIPs.</jats:p>

<jats:p>The Early‐Middle Jurassic is one of the crucial coal‐forming geologic periods in the world and an important target for hydrocarbon exploration in the Turpan‐Hami Basin, China. The paleoenvironment and vegetation reconstruction of the Early‐Middle Jurassic have been investigated using elemental geochemistry and palynological analysis to reveal paleoclimate evolution. A total of 48 genera of pteridophyte spore and 35 genera of gymnosperm pollen were identified, and 5 palynological assemblages were longitudinally divided, which showed significant differences in geochemical behaviours. The paleoenvironment was a transition from suboxidation to anoxia and then to an oxidation environment under freshwater conditions. The paleowater in the northern Taibei Sag was deeper than that in the southern part during the Middle Jurassic, which coincided with the sedimentary background of the sublacustrine fan in the north and the shallow braided river delta in the south. The paleovegetation evolved from mixed lowland–upland forest in the Hettangian‐Toarcian, to lowland fern forest in the Aalenian‐Bajocian, to upland conifers forest in the early Bathonian, to upland Cheirolepidiaceae forest in the late Bathonian‐Callovian. The Toarcian and Bathonian‐Callovian arid climate and the Hettangian‐Pliensbachian and Aalenian‐Bajocian warm‐humid climate were responses to the continued global warming events and the intensification of the East Asian monsoon circulation, respectively. The influence of the Bathonian‐Callovian aridification event on the sedimentary response in the southern Taibei Sag will be delayed due to the gradual southward migration of the depositional centre.</jats:p>

<jats:p>This comprehensive study investigates the organic matter characteristics within the Late Cretaceous Rakopi and Taniwha formations, based on data from four exploration wells situated in New Zealand's Taranaki Basin. It employs a multifaceted approach, integrating bulk geochemical analyses, biomarker measurements and carbon isotopes to unveil the geological history of these formations. Analytical results include total organic carbon content, ranging from 7.27 to 75.78 wt%, and generation potentials spanning from 28.24 to 309.16 mg hydrocarbon/g rock. These observations underscore the source rock potential of these Late Cretaceous strata. These rocks show a mixed organic matter of hydrogen‐rich Type II and Type II/III kerogens, as evidenced by hydrogen index values (HI) between 237 to 428 mg hydrocarbon/g rock. These formations demonstrate promise potential for both oil and gas generation. Biomarker analysis uncovers distinct signatures, featuring a pristane/phytane (Pr/Ph) ratio ranging from 3.27 to 10.91, a Tm/Ts ratio surpassing 7 and elevated concentrations of C<jats:sub>29</jats:sub> regular steranes relative to C<jats:sub>27</jats:sub> and C<jats:sub>28</jats:sub> regular steranes. These biomarker characteristics suggest a composite organic matter composition, influenced by terrigenous organic matter, likely deposited in oxygenated fluvial deltaic environments. Bulk carbon isotopic data corroborate these findings, highlighting the abundance of terrigenous organic matter. Collectively, these insights reveal that the coal and carbonaceous shale intervals in the examined wells are in the early stages of oil generation. Therefore, the Rakopi and Taniwha formations have not yet yielded commercially viable oil and/or gas quantities. In this case, these formations hold substantial promise for future exploration activities in relatively deep wells, with limited oil expulsion from coals.</jats:p>

<jats:p>The Weiningbeishan fold‐thrust belt (WFTB), located in the transitional zone of the Tibetan Plateau, Alxa Block and Ordos Basin, is an ancient intracontinental orogenic belt. In this article, structural analysis is conducted to more finely reveal differential deformation between the Devonian and Carboniferous strata in the WFTB. We found that the E–W‐trending open folds are mainly developed in the Upper Devonian Zhongning Formation (D<jats:sub>3</jats:sub><jats:italic>z</jats:italic>), while the E–W‐trending close and tight folds are mainly developed in the Carboniferous strata. The N–S minimum shortening strain of the bottom boundary of Member 2 of the Upper Devonian Zhongning Formation (D<jats:sub>3</jats:sub><jats:italic>z</jats:italic><jats:sup><jats:italic>2</jats:italic></jats:sup>) is 21.1%, whereas the N–S minimum shortening strain of the bottom boundary of Member 2 of the Upper Carboniferous Danliangshan Formation (C<jats:sub>2</jats:sub><jats:italic>d</jats:italic><jats:sup><jats:italic>2</jats:italic></jats:sup>) is 64.1%. We propose that the E–W‐trending open folds in the Upper Devonian Zhongning Formation (D<jats:sub>3</jats:sub><jats:italic>z</jats:italic>) and E–W‐trending close and tight folds in the Carboniferous strata were formed under the N–S compression during the Middle–Late Triassic. The Zhangyigou and Laoyagou faults are the main tear faults to accommodate differential displacement on the surface between the Upper Devonian Zhongning Formation (D<jats:sub>3</jats:sub><jats:italic>z</jats:italic>) in the east and Carboniferous strata in the middle, which change into a décollement fault in the deep part of the Dafosigou fold area in the middle to accommodate differential deformation between the deep Upper Devonian Zhongning Formation (D<jats:sub>3</jats:sub><jats:italic>z</jats:italic>) and Carboniferous strata. This study enables us to better understand the Mesozoic intracontinental deformation in response to far‐field plate‐boundary convergence in NW China.</jats:p>