地球科学最新文献

{"title":"Fluid-inclusion-petrography-guided chlorine isotopes in deeply buried continental halite reveal paleobrine and hydroclimate evolution","authors":"Xintao Wang, Yunqi Ma, Pei Ni, Yuqin Sun, Peng Cheng, Hui Tian, Yong Chen","doi":"10.1016/j.chemgeo.2026.123785","DOIUrl":"https://doi.org/10.1016/j.chemgeo.2026.123785","url":null,"abstract":"Halite δ<ce:sup loc=\"post\">37</ce:sup>Cl is a promising proxy for reconstructing paleobrine and hydroclimate evolution in continental evaporite systems, but its reliability in deeply buried deposits depends on distinguishing primary isotopic signals from diagenetic modification. Here, we integrate fluid-inclusion petrography with targeted Cl isotope analysis of modern halite from the Qarhan Playa and deeply buried Early Eocene bedded halite from the Dongying Depression, China. Paired FI-rich and FI-poor primary crystals from modern halite show absolute δ<ce:sup loc=\"post\">37</ce:sup>Cl differences of 0.01‰–0.54‰ (mean 0.28‰), but no systematic directional offset (mean signed difference = −0.02‰). Together with mass-balance constraints, these results indicate that inclusion-hosted brines exert a limited influence on measured primary-halite δ<ce:sup loc=\"post\">37</ce:sup>Cl without producing a detectable systematic isotopic bias. In contrast, altered crystals from deep-buried halite show larger absolute δ<ce:sup loc=\"post\">37</ce:sup>Cl differences from paired FI-rich primary crystals (0.23‰–2.02‰; mean 0.79‰), with shifts varying in both magnitude and direction. Burial-related closed-system brine–halite re-equilibration may modify the Cl concentration and potentially the δ<ce:sup loc=\"post\">37</ce:sup>Cl composition of inclusion-hosted brines without necessarily resetting bulk whole-crystal δ<ce:sup loc=\"post\">37</ce:sup>Cl, whereas open-system diagenetic fluid–halite interaction can overprint primary isotopic signatures. Petrographically screened FI-rich primary halite from the Dongying Depression preserves coherent δ<ce:sup loc=\"post\">37</ce:sup>Cl trends that, combined with sedimentological evidence, reveal spatially variable brine evolution during the mid- to late Early Eocene Climate Optimum and an overall arid hydroclimate punctuated by short-term dry–wet fluctuations, followed by generally wetter conditions in the late interval. These findings establish petrographic screening as critical for reliable δ<ce:sup loc=\"post\">37</ce:sup>Cl-based reconstruction of paleobrine and hydroclimate evolution in deeply buried continental evaporite systems.","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"14 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149274620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A multi-media review of polycyclic aromatic compounds in the Alberta Oil Sands Region","authors":"Md Noim Imtiazy, Prabin Rokaya","doi":"10.1016/j.earscirev.2026.105748","DOIUrl":"https://doi.org/10.1016/j.earscirev.2026.105748","url":null,"abstract":"Polycyclic aromatic compounds (PAC) are contaminants of major concern in Alberta's Oil Sands Region (OSR), yet research remains fragmented across environmental media and disciplines. This review synthesizes 107 peer-reviewed studies (2001–2025) to provide the first cross-media synthesis of PAC dynamics in the OSR. Atmospheric PAC concentrations generally fall within ranges reported for rural and semi-rural environments globally, with fugitive dust, wind-blown petroleum coke, and tailings ponds identified as key industrial sources. Atmospheric concentrations and deposition to snowpack and vegetation show consistent exponential distance-decay gradients, with alkylated PAC and dibenzothiophenes dominating near-industrial signatures. In aquatic systems, PAC concentrations are generally low to moderate and infrequently exceed available guidelines, which cover only a few parent PAC. Natural McMurray Formation outcrop erosion and hydrological processes exert strong, sometimes dominant, control over PAC loading in the Athabasca River and its tributaries, complicating source attribution. Nonetheless, lake sediment records document post-development increases in PAC fluxes and shifts toward petrogenic signatures, indicating industrial atmospheric inputs. In biota, PAC can cause sublethal developmental, immunological, and endocrine effects, but population-level impacts remain difficult to disentangle from co-occurring stressors such as nutrient enrichment and climate change. Persistent knowledge gaps include analytical heterogeneity across studies, widespread reliance on diagnostic ratios for source attribution, inadequate guidelines, spatial bias toward the surface-mineable Athabasca OSR, and arbitrarily designated central reference points that oversimplify emission heterogeneity. Advancing OSR PAC science will require standardized analytical frameworks, expanded compound coverage, integrated multi-media monitoring designs, advanced source-attribution tools, comprehensive and validated emissions/release inventories, and meaningful Indigenous community engagement.","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"6 1","pages":""},"PeriodicalIF":12.1,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149274838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards fractional vegetation cover mapping in complex mountain environments through a knowledge-guided unmixing framework","authors":"Yi Zhang, Bowen Li, Tao Yu, Shiming Li, Guiru Liu, Qing Liu, Letong Xu","doi":"10.1016/j.jag.2026.105652","DOIUrl":"https://doi.org/10.1016/j.jag.2026.105652","url":null,"abstract":"Mountain vegetation dynamics serve as sensitive indicators of environmental change, making accurate fractional cover mapping of primary components crucial for understanding ecosystem responses. This task has been facilitated by multispectral satellite imagery, particularly Sentinel-2, which provides continuous observations. To translate these observations into fractional cover maps, existing studies typically apply fraction estimation models to synthetic spectra derived from field-measured signatures. However, limited field surveys in mountain terrain present a data bottleneck for synthetic spectra construction, while complex vegetation composition introduces spectral ambiguities that existing methods struggle to represent. Therefore, this study develops a knowledge-guided unmixing framework for annual mapping of the fractional cover of herbaceous vegetation, woody vegetation, and bare land in mountain environments using Sentinel-2 time series. Specifically, to overcome data bottleneck, we develop a knowledge-guided strategy that automatically builds adaptive physio-phenological feature spaces to extract representative signatures. To resolve spectral ambiguity, we incorporate nonlinear mixing mechanisms to synthesize spectra that better represent complex mixing relationships. The synthetic library was then used to train Unmix-Net, a spectral-temporal regression model for fraction estimation. The framework was applied to the central Qilian Mountains and southern Hengduan Mountains spanning broad climatic gradients, validated with high-resolution UAV data. It achieved MAEs of 12.38 %, 8.58 %, and 9.82 % for herbaceous, woody, and bare land, outperforming existing models by up to 7.80 %. When implemented across landscapes ranging from arid steppes and alpine meadows to tropical rainforests, the framework maintained comparable performance. The comparative experiments further confirmed that the proposed extraction strategy improved the balance of component estimates, while combining complementary mixing mechanisms reduced estimation errors. By integrating domain knowledge into data-driven learning, this framework supports spatially continuous fractional vegetation mapping in mountain environments.","PeriodicalId":50341,"journal":{"name":"International Journal of Applied Earth Observation and Geoinformation","volume":"6 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149292753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic effects of the spring tropical Atlantic and Indian Ocean on early-summer Meiyu","authors":"Shankai Tang, Bicheng Huang, Xueying Wang, Yulai Gong, Xi Liu, Shaobo Qiao, Guolin Feng","doi":"10.1016/j.atmosres.2026.109412","DOIUrl":"https://doi.org/10.1016/j.atmosres.2026.109412","url":null,"abstract":"The early-summer Meiyu over the Yangtze River Basin (YRB) is jointly modulated by multiple factors, and the synergistic effect by the tropical Atlantic and Indian Oceans remains to be systematically revealed. By presenting the convergent empirical and modeling evidence, this study identifies three leading joint modes of the boreal spring tropical Atlantic and Indian Ocean (IO) sea surface temperature (SST)—the warm pool mode, the Atlantic dipole mode, and the Atlantic–IO gradient mode—that synergistically modulate Meiyu through distinct cross-seasonal and cross-basin pathways. The warm pool mode, often phase-locked with a preceding El Niño, acts as an important precondition sustaining the western North Pacific anomalous anticyclone (WNPAC) and leading to enhanced Meiyu. The Atlantic dipole mode emerges independently of ENSO but triggers a summertime developing La Niña, which enhances Meiyu over the lower YRB via triggering an eastward-displaced WNPAC. The Atlantic–IO gradient mode, coupled with a persistent La Niña, intensifies the Indian Summer Monsoon via cross-equatorial flows and upstream wave trains, subsequently exciting the Circumglobal Teleconnection (CGT) wave train. This induces a barotropic high-pressure anomaly over the YRB, resulting in a Meiyu deficit but more frequent heatwaves there. This work should help deepen the understanding of the complex causes of Meiyu and provide a reference for improving prediction capability.","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"13 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149290712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"River Basin Ecohydrological Processes under Changing Environments","authors":"Jianyun Zhang, Yanqing Lian, Dingbao Wang, Guoqing Wang, Changsen Zhao","doi":"10.1016/j.jhydrol.2026.136688","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136688","url":null,"abstract":"","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"35 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149292399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research Note: Enhancing the Convergent POCS Method Through Intermediate Value Correction","authors":"Yimin Sun,&nbsp;Miaoyang Yuan","doi":"10.1111/1365-2478.70272","DOIUrl":"https://doi.org/10.1111/1365-2478.70272","url":null,"abstract":"<div>\u0000 \u0000 <p>The convergent POCS (CP) method is a mathematically convergent approach for data reconstruction; however, its results are often contaminated by ringing noise. Through analysis, we identify the root cause as the multi-solution nature of the CP method. To address this issue, we propose the CP+ method, which proactively adjusts the intermediate value in the outer loop of the CP process, guiding the projection trajectory toward an improved solution. This enhancement improves reconstruction quality while suppressing ringing noise. A 2D seismic data reconstruction example is presented to demonstrate the effectiveness of the CP+ method.</p>\u0000 </div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"74 9","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149259409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"100-million-years-old “island-surfing”: SRµCT of Cretaceous genitals reveals the first fossils of the Gondwanan group Dalodesmidae","authors":"Jéhan Le Cadre, Dolev Fabrikant, Jörg U. Hammel, Jörg Spelda, Roland R. Melzer","doi":"10.1016/j.gr.2026.09.010","DOIUrl":"https://doi.org/10.1016/j.gr.2026.09.010","url":null,"abstract":"Lack of diagnostic characters in fossils is a widespread issue in palaeontology. Although Kachin amber (∼100 Ma) is yielding exceptional specimens, a major proportion of low preservation fossils are disregarded. In flat-backed millipedes (Polydesmida), this issue is critical as only two species are identified out of hundreds of reported fossils. With the popularisation of micro-tomography and synchrotron-based micro-tomography for palaeontology, it is important to assess their strengths in investigating difficult and low-preservation specimens. We report its success in capturing fully intact gonopods from two fossils of low preservation. Both specimens belong to the same new genus <ce:italic>Dalocarinatus</ce:italic> gen. nov., but represent two species: <ce:italic>D. luxuriosus</ce:italic> sp. nov. and <ce:italic>D. inopinatus</ce:italic> sp. nov. They are the oldest and definitive fossil representatives of the group Dalodesmidae, they also offer a glimpse of their presence on Burma Terrane, expanding their current-day geographical distribution, which is restricted to past Gondwanan regions.","PeriodicalId":12761,"journal":{"name":"Gondwana Research","volume":"5 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149290953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measuring and Mapping Urban NO2 Pollution Heterogeneity Using a Custom Pandora Spectrometer Experiment and Observations From TEMPO","authors":"R. H. Mooers,&nbsp;J. A. Geddes,&nbsp;C. Naughton,&nbsp;A. Pandey,&nbsp;B. K. Place,&nbsp;G. González Abad,&nbsp;N. Lombel","doi":"10.1029/2026JD047935","DOIUrl":"https://doi.org/10.1029/2026JD047935","url":null,"abstract":"<p>Nitrogen dioxide (NO₂) is a primary pollutant present at high concentrations in urban areas. Ground based measurements remain sparse and satellite observations rely on retrievals, so understanding intraurban, diurnal-scale changes in NO₂ is challenging. We present a novel methodology leveraging the sky scan capabilities of four Pandora spectrometers deployed around the Boston area to improve our understanding of intra-urban NO₂ variability. We collected sky scans in up to four directions per instrument per hour in addition to direct sun observations, yielding high-quality data across all site-azimuth pairs. The observations were applied to understand the role of wind conditions on driving spatial heterogeneity in column NO₂ abundance and local-scale diurnal patterns, finding that each wind type influences NO₂ differently. We leverage our experiment to understand the capabilities of the Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite instrument for tracking changes in NO₂ on intra-urban spatial scales and individual days, something that has not yet been examined in prior validation studies. Due to its value for measuring spatiotemporal variability, this approach can be used to more robustly constrain TEMPO and its uncertainties. Our comparisons with TEMPO in Boston advise caution when using data before 13 UTC as a bias persists, but in the afternoon we show that TEMPO captures similar dynamic range to the Pandoras, with differences likely attributable to spatial sampling mismatches. Our findings support the viability of a multi-azimuth sky scan experiment, and potentially broader adoption of such methodology across the global network of Pandoras.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 20","pages":""},"PeriodicalIF":3.8,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JD047935","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149259558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How climate change intensifies methane emissions from inland freshwater ecosystems: mechanisms, pathways, and feedback loops","authors":"Shuang Liu, Yu Xue, Feng Zhao, Meiqi Huang, Panpan Cui, Xiaoyu Cui, Yindong Tong","doi":"10.1016/j.earscirev.2026.105747","DOIUrl":"https://doi.org/10.1016/j.earscirev.2026.105747","url":null,"abstract":"Inland freshwater ecosystems are substantial but highly uncertain sources of atmospheric methane (CH<ce:inf loc=\"post\">4</ce:inf>), and their emissions can offset part of the apparent climatic benefit of terrestrial carbon uptake. Existing assessments have often examined CH<ce:inf loc=\"post\">4</ce:inf> production, oxidation, transport, and release as separate processes, limiting understanding of how climate change alters net emissions. Here, we argue that climate change does not simply enhance individual methane-producing processes. Instead, it can reorganize CH<ce:inf loc=\"post\">4</ce:inf> cycling in inland freshwater ecosystems by simultaneously altering CH<ce:inf loc=\"post\">4</ce:inf> production, storage, oxidation, transport, and pathway-specific release. We integrate recent advances into a source-filter-release continuum that links climatic forcing, ecosystem responses, CH<ce:inf loc=\"post\">4</ce:inf> biogeochemistry, and atmospheric emission. This framework shows how warming, ice loss, hydrological change, extreme events, and altered catchment inputs reshape thermal structure, oxygen and redox conditions, substrate supply, residence time, and gas-transfer pathways. The resulting responses are nonlinear and system specific. Storage and water-column structure are often important in lakes and reservoirs, whereas transport, habitat exchange and rapid evasion commonly exert stronger controls in rivers and streams. Net emissions may increase, decrease, or shift among pathways depending on the balance among methanogenesis, oxidative filtering, retention, and release. We further evaluate mitigation options that target source strength, oxidative filtering, internal storage, and hydrodynamically mediated release, while emphasizing annual whole-system emissions and the risk of shifting emissions across seasons, locations, or pathways. This perspective provides a mechanistic basis for improving greenhouse gas accounting, climate-feedback projections, and coordinated freshwater management.","PeriodicalId":11483,"journal":{"name":"Earth-Science Reviews","volume":"6 1","pages":""},"PeriodicalIF":12.1,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149274874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Progressive fracture and energy response of granite subjected to rapid localized flame heating","authors":"Qifeng Guo, Yunhong Guo, Libo Liu, Xiong Yin, Siying Wu, Yan Li, Pengbo Liu, Chao Peng","doi":"10.1016/j.enggeo.2026.109185","DOIUrl":"https://doi.org/10.1016/j.enggeo.2026.109185","url":null,"abstract":"The progressive fracture and energy responses of granite following rapid localized flame heating were investigated using three-point bending tests on untreated single-edge-notched beams and specimens heated to target surface temperatures of 200–600 °C and naturally cooled to room temperature. Acoustic emission (AE) and digital image correlation (DIC) measurements were combined with fracture-surface SEM observations and main-crack-path analysis. The results showed that the mean peak nominal stress decreased from 15.17 to 5.39 MPa with increasing target surface temperature, a reduction of approximately 64.5%, while mean failure CMOD and LPD increased monotonically and reached their maxima at 600 °C. Post-peak load degradation and crack propagation occupied most of the loading history, with 97.27–99.87% of the final cumulative AE absolute energy recorded after peak load. Representative post-peak b-values were lower than pre-peak values, indicating a greater relative contribution from high-amplitude events, while tensile-type AE events dominated the RA–AF classification. DIC showed upward strain localization from the notch tip and macroscopic failure dominated by opening. Crack paths varied non-monotonically with temperature, with the greatest deflection and tortuosity at 400 °C, where path correction reduced the calculated fracture energy by approximately 11.2%. Among the representative specimens, path-corrected fracture energy peaked at 180.51 N/m at 500 °C, whereas cumulative AE absolute energy peaked at 300 °C. These findings provide an experimental basis for evaluating granite fracture following localized thermal disturbance and for thermally assisted rock breaking.","PeriodicalId":11567,"journal":{"name":"Engineering Geology","volume":"28 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149290949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}