Continent and Life Evolution
ISSN: 3008-0851 (Print)
ISSN: 3008-086X (Online)
CODEN: CLEABK
Continent and life evolution: an international platform for earth system science
Among the planets currently known, Earth is unique not only because it harbors life, but also because its continents, oceans, atmosphere, climate, and biosphere have co-evolved as an integrated and self-transforming system over billions of years. The emergence and long-term persistence of habitable environments have not resulted from any single process, but from sustained interactions among deep Earth dynamics, surface processes, environmental change, and biological evolution. Since the formation of Earth approximately 4.6 billion years ago, continental growth and reworking, plate tectonics, ocean–atmosphere evolution, climatic transitions, biological innovation, mass extinctions, and Earth surface processes have been coupled within a dynamic Earth system (Wilde et al. 2001; Santosh 2010; Zerkle 2018; Zhai and Peng 2020; Zhu et al. 2021; Young et al. 2023; Zhao et al. 2023; Stern and Gerya 2024). Continents have not merely provided a passive physical substrate for weathering, sedimentation, nutrient cycling, ecological diversification, and human civilization; they have also actively regulated the environmental conditions under which life originated, diversified, and repeatedly reorganized. Conversely, life has profoundly reshaped Earth’s surface environments through the ecological engineering of reef structures and shell beds, modifying atmospheric composition, mediating biogeochemical cycles, influencing mineral formation, and transforming sedimentary and ecological systems (Peccerillo 2021; Hamidi 2022). Comparative studies of other terrestrial planets further broaden this perspective, particularly for reconstructing early Earth conditions where the geological record remains fragmentary. Understanding these long-term feedbacks among solid Earth processes, surface environments, and biological evolution is essential not only for reconstructing the history of our planet, but also for evaluating its future trajectory under climate change, biodiversity loss, resource exploitation, environmental degradation, and increasing human disturbance (Costanza et al. 2007; Bonan and Doney 2018; Folke et al. 2021). At the same time, Earth science is being rapidly transformed by the convergence of artificial intelligence and big-data analytics, cloud computing, human–machine interaction, quantum technologies, genomics and genome editing, nanoscience, polymer nanomaterial, and clean-energy technologies (Melnikov et al. 2018; Nayfach et al. 2021; Hultman et al. 2024). These technological breakthroughs provide opportunities and challenges for continent and life evolution under extreme conditions, spanning scales from microscopic mechanisms to planetary-scale processes and integrating insights across multiple scientific disciplines.
Freeze–thaw-driven microstructural evolution and collapsibility of Xinjiang loess: implications for climate-sensitive continental near-surface materials
Loess in seasonally frozen arid regions is highly sensitive to both freeze–thaw disturbance and subsequent wetting-induced collapse, yet the microstructural pathway by which freeze–thaw cycling modifies its collapsibility remains insufficiently quantified. In this study, Xinjiang loess was subjected to 0, 1, 3, 5, 7, and 10 freeze–thaw cycles, and its collapse behavior and microstructural evolution were investigated using collapsibility tests, particle-size analysis, scanning electron microscopy (SEM), Avizo-based quantitative pore analysis, and multivariate statistical methods. The results show that freeze–thaw cycling enhanced the collapsibility of the loess, with the collapsibility coefficient at 200 kPa increasing overall from 0.0809 in the untreated state to 0.115 after 10 cycles. This response was not strictly linear: limited changes occurred after 1–3 cycles, whereas a pronounced increase in collapsibility and microstructural deterioration appeared during 5–7 cycles, indicating a transition from local freeze–thaw disturbance to more extensive structural reorganization. Repeated freeze–thaw cycling promoted aggregate disintegration and particle refinement, as reflected by increased clay and silt contents and decreased sand content. However, the enhancement of collapsibility was more closely associated with pore-system reconstruction than with particle-size redistribution alone. Quantitative pore analysis showed that the total pore area ratio increased from 48.22% to 51.20% after 7 cycles and remained high after 10 cycles, while the macropore area ratio increased markedly from 6.75% to 20.01%, accompanied by reduced mesopore content and lower pore roundness. Pearson correlation analysis, PCA, and HCA consistently indicated that total pore area ratio and macropore area ratio were the pore-related parameters most strongly associated with the collapse response, whereas particle-size redistribution and pore-shape modification played secondary roles. These findings demonstrate that freeze–thaw-enhanced collapsibility in Xinjiang loess is controlled primarily by nonlinear pore-system opening and macropore development, providing a microstructure-based explanation for the destabilization of climate-sensitive continental near-surface materials under repeated freeze–thaw forcing.
Late Cenomanian radiolitid rudists from the Jingzhushan Formation of the northern Lhasa Terrane
This study documents a late Cenomanian (Late Cretaceous) radiolitid rudist assemblage from the basal part of the Jingzhushan Formation in the northern Lhasa Terrane, Qinghai-Tibetan Plateau. The radiolitid fauna includes Paronaites zuffardii, Eoradiolites liratus, Sauvagesia cf. sharpei, and Auroradiolites biconvexus, with the first three species constituting a characteristic late Cenomanian association widely distributed in the Mediterranean Tethys and the Middle East. Their presence in the Jingzhushan Formation, previously interpreted as deposited in alluvial-fan and braided-river systems, provides definitive evidence for a shallow-marine carbonate platform environment in the northern Lhasa Terrane during the late Cenomanian. The co-occurrence of the primitive genus Auroradiolites with more advanced radiolitids suggests a significant faunal transition and a notable radiation event of the Family Radiolitidae in eastern Tethys during the early Late Cretaceous. These findings contribute to understanding the paleogeographic evolution of the eastern Tethys, and the stratigraphic correlation of Cenomanian shallow-water carbonates between the eastern and western Tethys.
Geochronology and geochemistry of mafic rocks in the Wutai area, North China: constraints on the latest Neoarchean–Paleoproterozoic tectonic setting of the Trans-North China Orogen and the onset of plate tectonics
The Neoarchean-Paleoproterozoic is a key period for the North China Craton due to the formation of continental crust and the beginning of oceanic subduction. The amalgamation of the Eastern and Western blocks of the North China Craton remains debated, particularly regarding the timing, directionality (eastward vs. westward subduction), and number of collisional phases. Previous studies disproportionately focus on felsic lithologies, creating a critical mafic blind spot that obscures insights into mantle dynamics and crust-mantle interactions. Systematic investigation of Late Archean to Paleoproterozoic mafic suites was essential to reconcile conflicting tectonic models and refine the craton’s amalgamation history. In order to constrain the complex geological processes more clearly, we present new whole-rock geochemistry and zircon U-Pb geochronology for mafic rocks in the Wutai Complex. The Late Archean (2.56~2.54 Ga) gabbros are characterized by relatively depleted Nb–Ta and Zr–Hf anomalies, slightly positive Eu* anomalies, low K₂O concentrations, enrichments of LILE (Ba, CS, Th, and Rb), differentiated HFSE patterns and moderate Mg# values (43–53). They show positive εNd (t) values (+4.9–+6.1) and high (⁸⁷Sr/⁸⁶Sr)i ratios (0.70063–0.70091). Additionally, these gabbros have high Nb concentration (13.3–23.3) and display enrichments in light rare earth elements (LREE) (La/Yb)N = 7.00–8.96), high-field strength elements (HFSE, e.g., Nb, Ta, Zr), and high Nb/U and Nb/La ratios, suggesting a derivation from an arc-like mantle source. The gabbro melts were generated by a low degree of 4%–5% partial melting of garnet-spinel lherzolite mantle. The Paleoproterozoic (2.16~2.08 Ga) amphibolites also display depleted Nb-Ta and Zr-Hf anomalies, enriched light rare earth elements (LREEs), but show lower Eu* anomalies, εNd(t) values (+0.9–+1.2), and (⁸⁷Sr/⁸⁶Sr)i ratios (0.69770–0.69930). The amphibolites exhibit a geochemical signature marked by LREE enrichment, negative HFSE anomalies, and distinct Sm-Nd isotopic composition, suggesting a subduction-related magma source. The enrichment of Cs, Rb, Ba, and the depletion of Nb, Ta, P, and Ti, imply that their magma source was significantly modified by subducted crustal materials. The trace element ratios, such as K/Rb, Rb/Y, Nb/Y, Th/Zr, and so on, further indicate that the gabbros were derived from a mantle substantially altered by siliceous slab-derived melts, whereas the amphibolites originated from a mantle influenced by slab-derived melts and fluids. The amphibolites were generated by the 15% partial melting of garnet-spinel lherzolite and the 15% melting of spinel lherzolite at a shallower mantle source. In combination with the previously published data of mafic rocks in the Wutai Complex, we infer that the Late Archean gabbros suggest their derivation in a subduction-related setting, whereas the Paleoproterozoic amphibolites formed in a back-arc basin setting. These findings underscore a tectonic transition from Late Archean oceanic subduction to Paleoproterozoic lithospheric extension in the North China Craton, indicating that plate tectonics at least partly happened most likely in the latest Neoarchean.
Stratigraphic refinement unveils high-resolution shallow marine biotic dynamics immediately preceding the Late Ordovician Mass Extinction in South China
Exceptionally preserved Late Ordovician successions in South China offer a globally significant archive for investigating both the Great Ordovician Biodiversification Event (GOBE) and the Late Ordovician Mass Extinction (LOME). In contrast to the graptolitic facies that dominate much of the region, the late Katian carbonate deposits in the Jiangshan–Changshan–Yushan (JCY) area of East China (South China paleoplate), formerly referred to as the Sanqushan Formation (or its equivalents), are virtually the only strata in South China preserving diverse shallow marine biotas, providing rare ecological snapshots of the final biodiversity peak of the GOBE immediately preceding the LOME. Despite their importance, the lithostratigraphic framework and age constraints of these fossiliferous rocks remain debated. The prevailing view interprets the Xiazhen Formation as a nearshore equivalent of the Sanqushan Formation, with both units broadly assigned to a generalized late Katian age. Based on a critical review of integrated sedimentologic and paleontologic data, supplemented by new field observations, we support the interpretation that the Xiazhen Formation represents the upper portion of the ‘Sanqushan Formation’, and propose to elevate the latter to group rank to represent platform facies of this entire interval. The revised Sanqushan Group comprises, in ascending order, the Yaojiakeng, the Jitoushan, and the Xiazhen formations. The Yaojiakeng and the Jitoushan formations correlate more precisely with the Dicellograptus complexus Biozone, while the Xiazhen Formation aligns with the Paraorthograptus pacificus Biozone. This refined stratigraphic framework enables high-resolution reconstruction of biotic evolution prior to the LOME, offering new insights into regional ecological dynamics and their broader global significance.
Surface subsidence patterns and mechanisms of underlying goaf beneath a railway tunnel
Long-term deformation of abandoned mine workings endangers surface infrastructure, causing wall cracking, beam–column distortion and, in extreme cases, tilting or collapse. Here we track surface movement above the Taoping tunnel goaf beneath the Houyue railway (Shanxi, China) by combining 2015–2024 InSAR time-series, numerical modelling and probability-integral analysis. Contrary to widely held stability assumptions, subsidence is still accelerating more than a decade after extraction ceased. Five evolutionary stages are identified: (1) initial roof failure and local basin formation; (2) stress redistribution that loads the safety coal pillar; (3) progressive pillar crushing; (4) merger of adjacent goafs into a “balanced” instability structure; and (5) transformation of the local basin into a regional trough. Probability-integral forecasting indicates residual settlement will continue for roughly ten years before stabilization. The proposed stage-based framework enables long-term stability assessment and targeted remediation of similar legacy goafs, and supports safe railway operation and future land reuse.
