Pub Date : 2026-06-01Epub Date: 2026-01-30DOI: 10.1016/j.geotexmem.2026.01.006
Xinbei Lin , Zhen Huang , Li Shi , Yuanqiang Cai
Recently, a novel soft ground improvement technique termed airlift-assisted vacuum preloading (AAVP) has been proposed, which is featured by cyclically injecting pressurized air at the bottom of prefabricated vertical drains (PVDs) to expel water from the drain. This airlift process can achieve nearly lossless transmission of vacuum pressure along the PVDs and induce pneumatic fractures that enhance soil permeability. In this study, a nonlinear consolidation model was developed with full consideration of the time-varying pressure condition and the permeability improvement associated with cyclic airlift operations. The analytical solution was obtained by employing the piecewise linearization technique, and was first verified by degenerating it into conventional vacuum preloading (CVP) process and comparing to the classical drain-well solution. The complete solution was further validated against large-scale model test data. Parametric analyses revealed that, compared with CVP, AAVP significantly accelerates the consolidation process, exhibiting not only faster pore pressure dissipation but also a greater magnitude of dissipation that exceeds the applied vacuum. Theoretical results indicate that the advantages of AAVP become more pronounced under greater treatment depths and in soil with adverse conditions such as smear and clogging effects, highlighting its strong potential for application in ultra-thick soft deposits and high-water-content reclamation land.
{"title":"Consolidation model for soft ground under airlift-assisted vacuum preloading","authors":"Xinbei Lin , Zhen Huang , Li Shi , Yuanqiang Cai","doi":"10.1016/j.geotexmem.2026.01.006","DOIUrl":"10.1016/j.geotexmem.2026.01.006","url":null,"abstract":"<div><div>Recently, a novel soft ground improvement technique termed airlift-assisted vacuum preloading (AAVP) has been proposed, which is featured by cyclically injecting pressurized air at the bottom of prefabricated vertical drains (PVDs) to expel water from the drain. This airlift process can achieve nearly lossless transmission of vacuum pressure along the PVDs and induce pneumatic fractures that enhance soil permeability. In this study, a nonlinear consolidation model was developed with full consideration of the time-varying pressure condition and the permeability improvement associated with cyclic airlift operations. The analytical solution was obtained by employing the piecewise linearization technique, and was first verified by degenerating it into conventional vacuum preloading (CVP) process and comparing to the classical drain-well solution. The complete solution was further validated against large-scale model test data. Parametric analyses revealed that, compared with CVP, AAVP significantly accelerates the consolidation process, exhibiting not only faster pore pressure dissipation but also a greater magnitude of dissipation that exceeds the applied vacuum. Theoretical results indicate that the advantages of AAVP become more pronounced under greater treatment depths and in soil with adverse conditions such as smear and clogging effects, highlighting its strong potential for application in ultra-thick soft deposits and high-water-content reclamation land.</div></div>","PeriodicalId":55096,"journal":{"name":"Geotextiles and Geomembranes","volume":"54 3","pages":"Pages 430-442"},"PeriodicalIF":6.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080572","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}
Pub Date : 2026-06-01Epub Date: 2026-02-10DOI: 10.1016/j.atmosres.2026.108847
Dickson Mbigi, Zacharia Florence Mtewele
As one of the prominent oceanic regions exhibiting high interannual variability of sea surface temperature (SST), the southern Indian and Atlantic Oceans have been found to exert strong impacts on January–February-March (JFM) rainfall in southern Tanzania. The JFM rainfall is found to be significantly linked to the subtropical Indian Ocean Dipole (SIOD)-like SST pattern over the southern Indian Ocean and southern Atlantic Ocean Tripole (SAOT)-like SST structure over the southern Atlantic Ocean. This relationship is linearly independent of the effects of El Niño–Southern Oscillation and the Indian Ocean dipole. The presence of a weakened Mascarene high associated with the negative SIOD phase leads to southerly wind anomalies across the Mozambique Channel, which enhances moisture transport into southern Tanzania and rainfall over the region. The SAOT, on the other hand, excites a zonal elongated wave train-like pattern that induces large-scale cyclonic circulation over the southern Indian Ocean. Subsequently, the western flank of the cyclonic circulation excites southerly wind anomalies traversing through the Mozambique Channel towards the study region, leading to rainfall over the study region. Moreover, the observed wave train-like pattern is echoed in the upper levels, but the anticyclonic center over southern Australia expands further towards northern Madagascar. At this position, the associated anticyclonic wind anomalies reach southern Tanzania to create a divergence condition, enhancing rainfall conditions. Finally, the joint SIOD and SAOT indices show enhanced contribution to the rainfall, explaining about 28% of rainfall variability.
{"title":"Influence of sea surface temperature in the southern Indian and Atlantic Oceans on austral summer rainfall in southern Tanzania","authors":"Dickson Mbigi, Zacharia Florence Mtewele","doi":"10.1016/j.atmosres.2026.108847","DOIUrl":"10.1016/j.atmosres.2026.108847","url":null,"abstract":"<div><div>As one of the prominent oceanic regions exhibiting high interannual variability of sea surface temperature (SST), the southern Indian and Atlantic Oceans have been found to exert strong impacts on January–February-March (JFM) rainfall in southern Tanzania. The JFM rainfall is found to be significantly linked to the subtropical Indian Ocean Dipole (SIOD)-like SST pattern over the southern Indian Ocean and southern Atlantic Ocean Tripole (SAOT)-like SST structure over the southern Atlantic Ocean. This relationship is linearly independent of the effects of El Niño–Southern Oscillation and the Indian Ocean dipole. The presence of a weakened Mascarene high associated with the negative SIOD phase leads to southerly wind anomalies across the Mozambique Channel, which enhances moisture transport into southern Tanzania and rainfall over the region. The SAOT, on the other hand, excites a zonal elongated wave train-like pattern that induces large-scale cyclonic circulation over the southern Indian Ocean. Subsequently, the western flank of the cyclonic circulation excites southerly wind anomalies traversing through the Mozambique Channel towards the study region, leading to rainfall over the study region. Moreover, the observed wave train-like pattern is echoed in the upper levels, but the anticyclonic center over southern Australia expands further towards northern Madagascar. At this position, the associated anticyclonic wind anomalies reach southern Tanzania to create a divergence condition, enhancing rainfall conditions. Finally, the joint SIOD and SAOT indices show enhanced contribution to the rainfall, explaining about 28% of rainfall variability.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"336 ","pages":"Article 108847"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153121","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}
Pub Date : 2026-06-01Epub Date: 2026-01-21DOI: 10.1016/j.cretres.2026.106317
Vladimir N. Makarkin
The subfamily Cretanallachiinae is elevated to a family level, Cretanallachiidae, stat. nov. Its autapomorphies are bipectinate antennae in males and a long ventro-caudal extension of the 9th tergite in females. The family is known only from mid-Cretaceous Kachin amber. It is likely closely related to Dilaridae, an undescribed ithonoid-like taxon from the Middle Jurassic, and to a lesser extent Ithonidae. They lived in humid tropical forests with diverse angiosperms and probably fed on their flowers (nectar and/or pollen) using relatively long sucking mouthparts.
{"title":"Cretanallachiidae – a new family of the specialized Cretaceous Neuroptera","authors":"Vladimir N. Makarkin","doi":"10.1016/j.cretres.2026.106317","DOIUrl":"10.1016/j.cretres.2026.106317","url":null,"abstract":"<div><div>The subfamily Cretanallachiinae is elevated to a family level, Cretanallachiidae, stat. nov. Its autapomorphies are bipectinate antennae in males and a long ventro-caudal extension of the 9th tergite in females. The family is known only from mid-Cretaceous Kachin amber. It is likely closely related to Dilaridae, an undescribed ithonoid-like taxon from the Middle Jurassic, and to a lesser extent Ithonidae. They lived in humid tropical forests with diverse angiosperms and probably fed on their flowers (nectar and/or pollen) using relatively long sucking mouthparts.</div></div>","PeriodicalId":55207,"journal":{"name":"Cretaceous Research","volume":"182 ","pages":"Article 106317"},"PeriodicalIF":1.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147385521","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}
Pub Date : 2026-06-01Epub Date: 2026-01-26DOI: 10.1016/j.gr.2025.12.022
Xiang Ren , Yunpeng Dong , Inna Safonova , Shengsi Sun , Dengfeng He , Xiaoyan Zhao , Yuangang Yue , Bo Hui , Qiuming Pei , Baoping Gan
The southern East Kunlun Orogen (EKO) experienced protracted orogeny linked to the Proto-Tethys and Paleo-Tethys oceans. However, the evolution of the Proto-Tethys Ocean remains much less understood leaving the question of the timing of subduction initiation and magmatism. Here, we studied three early Paleozoic plutons exposed in the southern EKO: Kekesha (KKS) and Xialawen (XLW) gabbro-dioritic plutons and Longwakalu (LWKL) granitic pluton for geochronology, geochemistry and Sr-Nd-Hf isotopes. A KKS quartz diorite, XLW hornblende gabbro, and LWKL granite crystallized at 494, 470 and 477 Ma, respectively. The KKS gabbro-granodiorite series and XLW hornblende gabbros are enriched in light rare earth elements and large ion lithophile elements, but depleted in high strength field elements. The LWKL granites possess adakitic features: high Na2O content, Sr/Y and La/YbN ratios and differentiated heavy REEs. Isotopically, XLW hornblende gabbros and LWKL granites are less enriched isotopes (εNd(t) = −4.3 to −3.9; εHf(t) = −4.6 to +2.0) than KKS gabbro and granodiorite (εNd(t) = −7.0; εHf(t) = −7.2 to −4.8). Sr-Nd isotopic modeling suggests that KKS and XLW plutons were derived through partial melting of mantle wedge modified by different amounts of subducted terrigenous-dominated sediment derived melts. The LWKL adakitic granites were formed by high-pressure reworking of underplated arc-type intermediate rocks. The emplacement of early Paleozoic gabbro-granodiorite series and adakitic granites was related to subduction of the Proto-Tethys Ocean which started no later than ca. 500 Ma. Our new data along with available ages suggest that the supra-subduction magmatism of the Proto-Tethys Ocean in the southern EKO is episodic with peaks at ca. 495, 470, and 430 Ma. The first two episodes of magmatism mainly represent melting of enriched mantle wedge, and the third is the main pulse of magmatism formed by simultaneous melting of multiple sources of crustal rocks, subducted oceanic slab and mantle wedge.
{"title":"Episodic early Paleozoic arc magmatism of the Proto-Tethys Ocean: Evidence from geochronology, geochemistry and Sr-Nd-Hf isotopes of plutonic rocks in the southern East Kunlun Orogen","authors":"Xiang Ren , Yunpeng Dong , Inna Safonova , Shengsi Sun , Dengfeng He , Xiaoyan Zhao , Yuangang Yue , Bo Hui , Qiuming Pei , Baoping Gan","doi":"10.1016/j.gr.2025.12.022","DOIUrl":"10.1016/j.gr.2025.12.022","url":null,"abstract":"<div><div>The southern East Kunlun Orogen (EKO) experienced protracted orogeny linked to the Proto-Tethys and Paleo-Tethys oceans. However, the evolution of the Proto-Tethys Ocean remains much less understood leaving the question of the timing of subduction initiation and magmatism. Here, we studied three early Paleozoic plutons exposed in the southern EKO: Kekesha (KKS) and Xialawen (XLW) gabbro-dioritic plutons and Longwakalu (LWKL) granitic pluton for geochronology, geochemistry and Sr-Nd-Hf isotopes. A KKS quartz diorite, XLW hornblende gabbro, and LWKL granite crystallized at 494, 470 and 477 Ma, respectively. The KKS gabbro-granodiorite series and XLW hornblende gabbros are enriched in light rare earth elements and large ion lithophile elements, but depleted in high strength field elements. The LWKL granites possess adakitic features: high Na<sub>2</sub>O content, Sr/Y and La/Yb<sub>N</sub> ratios and differentiated heavy REEs. Isotopically, XLW hornblende gabbros and LWKL granites are less enriched isotopes (εNd<sub>(t)</sub> = −4.3 to −3.9; εHf<sub>(t)</sub> = −4.6 to +2.0) than KKS gabbro and granodiorite (εNd<sub>(t)</sub> = −7.0; εHf<sub>(t)</sub> = −7.2 to −4.8). Sr-Nd isotopic modeling suggests that KKS and XLW plutons were derived through partial melting of mantle wedge modified by different amounts of subducted terrigenous-dominated sediment derived melts. The LWKL adakitic granites were formed by high-pressure reworking of underplated arc-type intermediate rocks. The emplacement of early Paleozoic gabbro-granodiorite series and adakitic granites was related to subduction of the Proto-Tethys Ocean which started no later than ca. 500 Ma. Our new data along with available ages suggest that the supra-subduction magmatism of the Proto-Tethys Ocean in the southern EKO is episodic with peaks at ca. 495, 470, and 430 Ma. The first two episodes of magmatism mainly represent melting of enriched mantle wedge, and the third is the main pulse of magmatism formed by simultaneous melting of multiple sources of crustal rocks, subducted oceanic slab and mantle wedge.</div></div>","PeriodicalId":12761,"journal":{"name":"Gondwana Research","volume":"154 ","pages":"Pages 44-63"},"PeriodicalIF":7.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048047","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}
Pub Date : 2026-06-01Epub Date: 2026-01-18DOI: 10.1016/j.gr.2025.12.010
Yue Feng , Xianming Xiao , Enze Wang , Chengang Lu , Changrong Li , Gang Li , Yineng Tan
Organic matter-rich shale, a widely developed fine-grained sedimentary rock, hosts critical unconventional petroleum resources. Accurately assessing the resource potential and economic value of shale oil reservoirs is crucial for energy strategy decision-making, yet two challenges persist: evaluating oil mobility, and addressing light hydrocarbon evaporation. This study provides a review of these two critical dimensions. Laboratory testing forms the foundation of oil mobility assessment. In practice, method selection should be guided by the specific geological settings, data availability, and economic considerations. Notably, artificial intelligence offers the potential to generate accurate predictions even from limited datasets. This study establishes a generalizable framework validated through a case study on oil mobility evaluation under small-sample dataset scenarios. The second part divides the light hydrocarbon loss process from coring to experimental data acquisition into four distinct stages. The loss is continuously influenced by time-related degradation, with each stage characterized by different controlling factors. Nonetheless, the oil properties of shale and its own attributes remain consistent overarching influences. Minimizing additional losses through comprehensive and practical strategies represents the most effective solution. Future advances in experimental technologies, refined frameworks, and the deep mining and integration of data will enhance assessment accuracy. The findings of this study are expected to provide a solid theoretical foundation for the precise evaluation of resources in shale systems and the efficient delineation of prospective exploration targets.
{"title":"Oil mobility evaluation and light hydrocarbon restoration in shale reservoirs: a review","authors":"Yue Feng , Xianming Xiao , Enze Wang , Chengang Lu , Changrong Li , Gang Li , Yineng Tan","doi":"10.1016/j.gr.2025.12.010","DOIUrl":"10.1016/j.gr.2025.12.010","url":null,"abstract":"<div><div>Organic matter-rich shale, a widely developed fine-grained sedimentary rock, hosts critical unconventional petroleum resources. Accurately assessing the resource potential and economic value of shale oil reservoirs is crucial for energy strategy decision-making, yet two challenges persist: evaluating oil mobility, and addressing light hydrocarbon evaporation. This study provides a review of these two critical dimensions. Laboratory testing forms the foundation of oil mobility assessment. In practice, method selection should be guided by the specific geological settings, data availability, and economic considerations. Notably, artificial intelligence offers the potential to generate accurate predictions even from limited datasets. This study establishes a generalizable framework validated through a case study on oil mobility evaluation under small-sample dataset scenarios. The second part divides the light hydrocarbon loss process from coring to experimental data acquisition into four distinct stages. The loss is continuously influenced by time-related degradation, with each stage characterized by different controlling factors. Nonetheless, the oil properties of shale and its own attributes remain consistent overarching influences. Minimizing additional losses through comprehensive and practical strategies represents the most effective solution. Future advances in experimental technologies, refined frameworks, and the deep mining and integration of data will enhance assessment accuracy. The findings of this study are expected to provide a solid theoretical foundation for the precise evaluation of resources in shale systems and the efficient delineation of prospective exploration targets.</div></div>","PeriodicalId":12761,"journal":{"name":"Gondwana Research","volume":"154 ","pages":"Pages 122-154"},"PeriodicalIF":7.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995720","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}
Pub Date : 2026-06-01Epub Date: 2026-01-16DOI: 10.1016/j.palwor.2026.201078
Luciano Alessandretti , Lucas Veríssimo Warren , Heitor Francischini , Caio César Rangel , Beatriz Christofoletti , Leandro Gustavo da Silva Albino , Leonardo Cardoso Moura , Daniel Sedorko
Dinosaur undertracks are described in the Upper Cretaceous Capacete Formation of the Sanfranciscana Basin, southeastern Brazil. These vertebrate traces are preserved in fine-grained deposits deposited in muddy and vegetated floodplain settings associated with a meandering river system active during the Campanian–Maastrichtian. Based on sedimentologic data, morphostructural analysis, and comparisons with analogous Cretaceous ichnofossils, we interpret these structures as undertracks produced by sauropods. Notably, although other occurrences of footprints and undertracks are known in younger units, no dinosaur fossils have yet been recovered in the Upper Cretaceous of the Sanfranciscana Basin. However, they are widespread in chronocorrelated units from the Bauru Basin, deposited by fluvial distributary and lacustrine systems under arid to semi-arid climatic conditions. During the Late Cretaceous, these two basins were putatively separated due to the uplift of the Alto Paranaíba High (APH) in the central part of the South American Platform. Our new sedimentologic and paleontologic data from the Sanfranciscana Basin, combined with regional paleogeography and paleoclimate reconstructions, suggest that a rain shadow effect played a key role in influencing precipitation patterns in the northern side of the APH. In this scenario of orographic rainfall, sauropod populations likely migrated from the Bauru Basin in the Southern Hot Arid Belt to the Sanfranciscana Basin in the Equatorial Humid Belt, possibly driven by droughts and shortages of food and water. This inferred migratory pathway likely involved a lowland-upland-lowland journey of dinosaur herds through the APH, eventually leading them to the humid floodplains of the Sanfranciscana Basin, where resources such as food and water were more abundant.
在巴西东南部圣弗朗西斯卡纳盆地的上白垩纪Capacete组中描述了恐龙的足迹。这些脊椎动物的痕迹被保存在细小的沉积物中，这些沉积物沉积在泥泞和植被覆盖的洪泛区，与坎帕尼亚-马斯特里赫特时期活跃的蜿蜒河流系统有关。根据沉积学资料、形态结构分析以及与类似白垩纪鱼化石的比较，我们认为这些结构是蜥脚类动物留下的足迹。值得注意的是，尽管在更年轻的恐龙群中也发现了其他的脚印和足迹，但在旧金山盆地的上白垩纪还没有发现恐龙化石。然而，它们广泛存在于宝鲁盆地的时间相关单元中，这些单元是在干旱至半干旱气候条件下由河流支流和湖泊系统沉积的。在晚白垩世，由于南美地台中部的Alto Paranaíba High （APH）的隆升，推测这两个盆地是分开的。本文利用旧金山盆地沉积学和古生物学的新资料，结合区域古地理和古气候的重建，表明雨影效应在影响APH北侧降水格局中发挥了关键作用。在这种地形降雨的情况下，蜥脚类动物可能会从南部热干旱带的博鲁盆地迁移到赤道湿润带的旧金山盆地，这可能是由于干旱和食物和水的短缺。这种推断的迁徙路径可能涉及恐龙群通过APH的低地-高地-低地之旅，最终将它们带到旧金山盆地潮湿的洪泛平原，那里的食物和水等资源更为丰富。
{"title":"Late Cretaceous sauropod dinosaur undertracks in floodplain deposits of Sanfranciscana Basin, Brazil, and their paleoecological significance","authors":"Luciano Alessandretti , Lucas Veríssimo Warren , Heitor Francischini , Caio César Rangel , Beatriz Christofoletti , Leandro Gustavo da Silva Albino , Leonardo Cardoso Moura , Daniel Sedorko","doi":"10.1016/j.palwor.2026.201078","DOIUrl":"10.1016/j.palwor.2026.201078","url":null,"abstract":"<div><div>Dinosaur undertracks are described in the Upper Cretaceous Capacete Formation of the Sanfranciscana Basin, southeastern Brazil. These vertebrate traces are preserved in fine-grained deposits deposited in muddy and vegetated floodplain settings associated with a meandering river system active during the Campanian–Maastrichtian. Based on sedimentologic data, morphostructural analysis, and comparisons with analogous Cretaceous ichnofossils, we interpret these structures as undertracks produced by sauropods. Notably, although other occurrences of footprints and undertracks are known in younger units, no dinosaur fossils have yet been recovered in the Upper Cretaceous of the Sanfranciscana Basin. However, they are widespread in chronocorrelated units from the Bauru Basin, deposited by fluvial distributary and lacustrine systems under arid to semi-arid climatic conditions. During the Late Cretaceous, these two basins were putatively separated due to the uplift of the Alto Paranaíba High (APH) in the central part of the South American Platform. Our new sedimentologic and paleontologic data from the Sanfranciscana Basin, combined with regional paleogeography and paleoclimate reconstructions, suggest that a rain shadow effect played a key role in influencing precipitation patterns in the northern side of the APH. In this scenario of orographic rainfall, sauropod populations likely migrated from the Bauru Basin in the Southern Hot Arid Belt to the Sanfranciscana Basin in the Equatorial Humid Belt, possibly driven by droughts and shortages of food and water. This inferred migratory pathway likely involved a lowland-upland-lowland journey of dinosaur herds through the APH, eventually leading them to the humid floodplains of the Sanfranciscana Basin, where resources such as food and water were more abundant.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 3","pages":"Article 201078"},"PeriodicalIF":1.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116668","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}
Pub Date : 2026-06-01Epub Date: 2026-01-30DOI: 10.1016/j.atmosres.2026.108819
Min Zhao , Tie Dai , Yueming Cheng , Daisuke Goto , Keiya Yumimoto , Guangyu Shi
This study investigates the accuracy of aerosol optical thickness (AOT) forecasts and analyses during a whole year, by assimilating AOT retrievals from the Naval Research Laboratory (NRL) Moderate Resolution Imaging Spectroradiometer (MODIS) into the aerosol-coupled Non-hydrostatic ICosahedral Atmospheric Model. We explore the impact of data assimilation on aerosol direct radiative effect (DRE), taking into account the interactions between aerosol particles and radiation. Evaluation against the assimilated MODIS AOT data shows an improvement in the AOT fields. The root mean square error (RMSE) dropped from 0.027 in the free-run to 0.018 (a 33% reduction) for the forecast and to 0.017 (a 37% reduction) for the analysis, while the correlation coefficient rose from 0.640 (free-run) to 0.911 (forecast) and 0.986 (analysis), respectively. Furthermore, the most significant improvements were observed during the peak biomass burning period from August to October. This enhanced performance is further certified independently by Aerosol Robotic Network (AERONET) observations, which show a reduction in RMSE from 0.050 (free-run) to 0.038 (forecast) and 0.040 (analysis), alongside a marked rise in correlation coefficient to 0.810 and 0.884, respectively. The forecast DRE under clear-sky condition at the TOA is −2.69 ± 2.02 W/m2 and at the surface is −4.04 ± 2.96 W/m2. Under all-sky conditions, aerosol DRE are influenced by clouds, the forecast DRE under all-sky condition at the TOA is −1.45 ± 1.26 W/m2 and at the surface is −2.74 ± 1.98 W/m2.
{"title":"Global assimilation of NRL MODIS aerosol optical thickness and its impact on aerosol direct radiative effect over a full year","authors":"Min Zhao , Tie Dai , Yueming Cheng , Daisuke Goto , Keiya Yumimoto , Guangyu Shi","doi":"10.1016/j.atmosres.2026.108819","DOIUrl":"10.1016/j.atmosres.2026.108819","url":null,"abstract":"<div><div>This study investigates the accuracy of aerosol optical thickness (AOT) forecasts and analyses during a whole year, by assimilating AOT retrievals from the Naval Research Laboratory (NRL) Moderate Resolution Imaging Spectroradiometer (MODIS) into the aerosol-coupled Non-hydrostatic ICosahedral Atmospheric Model. We explore the impact of data assimilation on aerosol direct radiative effect (DRE), taking into account the interactions between aerosol particles and radiation. Evaluation against the assimilated MODIS AOT data shows an improvement in the AOT fields. The root mean square error (RMSE) dropped from 0.027 in the free-run to 0.018 (a 33% reduction) for the forecast and to 0.017 (a 37% reduction) for the analysis, while the correlation coefficient rose from 0.640 (free-run) to 0.911 (forecast) and 0.986 (analysis), respectively. Furthermore, the most significant improvements were observed during the peak biomass burning period from August to October. This enhanced performance is further certified independently by Aerosol Robotic Network (AERONET) observations, which show a reduction in RMSE from 0.050 (free-run) to 0.038 (forecast) and 0.040 (analysis), alongside a marked rise in correlation coefficient to 0.810 and 0.884, respectively. The forecast DRE under clear-sky condition at the TOA is −2.69 ± 2.02 W/m<sup>2</sup> and at the surface is −4.04 ± 2.96 W/m<sup>2</sup>. Under all-sky conditions, aerosol DRE are influenced by clouds, the forecast DRE under all-sky condition at the TOA is −1.45 ± 1.26 W/m<sup>2</sup> and at the surface is −2.74 ± 1.98 W/m<sup>2</sup>.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"336 ","pages":"Article 108819"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089730","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}
Urban environments alter local climate and air quality through concentrated emissions of heat and pollutants, giving rise to effects such as Urban Heat Island (UHI) and Urban Pollution Island (UPI). These microclimatic phenomena have seen growth due to industrialisation and urbanisation. Their coupled interaction in the context of Indian cities, however, remains poorly understood. In this study, we have investigated the evolution of UHI and UPI over a megacity of India, Kolkata, with a focus on Kolkata Metropolitan Area (KMA) by analysing Remote Sensing (MODIS) and in situ measurements (CPCB) of Land Surface Temperature (LST), UHI, Aerosol Optical Depth (AOD), Direct and Diffuse Solar Radiation, and Particulate Matter (PM2.5 and PM10) for a collective period of 2001–2024. UHI and UPI were observed over KMA, with both Nighttime LST (NLST) and Daytime LST (DLST) as well as AOD having significantly higher values over the urban region by +1.79 °C, +2.92 °C, and 0.18, respectively, than in rural areas. The results also suggested that the magnitudes of UHI and UPI are increasing over the years for KMA. As a result of increasing UPI, the study observed a simultaneous reduction of direct solar radiation by 22.64 W/m2 and an increase of diffuse radiation by 18.82 W/m2 over urban areas for the study period. The study suggests that the UPI and UHI may influence each other through direct and diffuse radiative forcing, and that the modulation of urban surface energy balance may occur due to these changes, which may be a link to unprecedented weather events over the region. The results provide a scientific basis for developing policies on regional climate adaptation and air quality management in Indian cities.
{"title":"Revisiting the Urban heat and pollution Islands over the Kolkata metropolitan area, India","authors":"Pragya Pandey , Bhishma Tyagi , Pradeep Kumar , Saroj Kumar Sahu , Kuldeep Sharma","doi":"10.1016/j.pce.2026.104330","DOIUrl":"10.1016/j.pce.2026.104330","url":null,"abstract":"<div><div>Urban environments alter local climate and air quality through concentrated emissions of heat and pollutants, giving rise to effects such as Urban Heat Island (UHI) and Urban Pollution Island (UPI). These microclimatic phenomena have seen growth due to industrialisation and urbanisation. Their coupled interaction in the context of Indian cities, however, remains poorly understood. In this study, we have investigated the evolution of UHI and UPI over a megacity of India, Kolkata, with a focus on Kolkata Metropolitan Area (KMA) by analysing Remote Sensing (MODIS) and in situ measurements (CPCB) of Land Surface Temperature (LST), UHI, Aerosol Optical Depth (AOD), Direct and Diffuse Solar Radiation, and Particulate Matter (PM<sub>2.5</sub> and PM<sub>10</sub>) for a collective period of 2001–2024. UHI and UPI were observed over KMA, with both Nighttime LST (NLST) and Daytime LST (DLST) as well as AOD having significantly higher values over the urban region by +1.79 °C, +2.92 °C, and 0.18, respectively, than in rural areas. The results also suggested that the magnitudes of UHI and UPI are increasing over the years for KMA. As a result of increasing UPI, the study observed a simultaneous reduction of direct solar radiation by 22.64 W/m<sup>2</sup> and an increase of diffuse radiation by 18.82 W/m<sup>2</sup> over urban areas for the study period. The study suggests that the UPI and UHI may influence each other through direct and diffuse radiative forcing, and that the modulation of urban surface energy balance may occur due to these changes, which may be a link to unprecedented weather events over the region. The results provide a scientific basis for developing policies on regional climate adaptation and air quality management in Indian cities.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"143 ","pages":"Article 104330"},"PeriodicalIF":4.1,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146174200","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}
Pub Date : 2026-06-01Epub Date: 2026-02-11DOI: 10.1016/j.clay.2026.108163
Seongyeop Kim, Yeongkyoo Kim
Understanding the mechanisms of biotite weathering is critical for elucidating geochemical cycling and soil formation. This study provides key mechanistic insights by systematically investigating artificial biotite weathering using a sodium tetraphenylborate (Na-TPB)-based method and evaluating the effects of reaction conditions—namely, the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition, including the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition on weathering pathways, using two biotite samples (BR and CA) with different initial Mg/(Mg + Fe) ratios and halogen contents. The results demonstrated that increasing the number of K+ extraction cycles led to greater weathering than prolonging the reaction time, as this created a sustained, steep K+ concentration gradient. A critical finding was that the pre-oxidation of structural iron significantly retarded K+ leaching by altering the biotite's internal electrostatic forces. This was quantitatively confirmed by X-ray photoelectron spectroscopy (XPS), which showed a clear correlation between increased surface Fe3+/Fe2+ ratios and slower weathering kinetics. Furthermore, iron oxidation appeared to promote the formation of irregular mixed-layer structures (biotite–vermiculite layers), a plausible mechanistic consequence of heterogeneous structural cation redistribution. Comparative experiments of different initial compositions revealed that the CA biotite exhibited greater weathering resistance than the BR sample. This is because its distinct initial composition (higher halogen content and Fe3+/Fe2+ ratio) enhanced K+ retention. These findings highlight the decisive roles of structural iron oxidation and initial chemical composition in controlling biotite weathering rates and pathways and the formation of secondary mineral phases.
{"title":"Mechanistic insights into biotite weathering: effects of structural and physicochemical factors on Na-TPB-induced potassium leaching","authors":"Seongyeop Kim, Yeongkyoo Kim","doi":"10.1016/j.clay.2026.108163","DOIUrl":"10.1016/j.clay.2026.108163","url":null,"abstract":"<div><div>Understanding the mechanisms of biotite weathering is critical for elucidating geochemical cycling and soil formation. This study provides key mechanistic insights by systematically investigating artificial biotite weathering using a sodium tetraphenylborate (Na-TPB)-based method and evaluating the effects of reaction conditions—namely, the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition, including the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition on weathering pathways, using two biotite samples (BR and CA) with different initial Mg/(Mg + Fe) ratios and halogen contents. The results demonstrated that increasing the number of K<sup>+</sup> extraction cycles led to greater weathering than prolonging the reaction time, as this created a sustained, steep K<sup>+</sup> concentration gradient. A critical finding was that the pre-oxidation of structural iron significantly retarded K<sup>+</sup> leaching by altering the biotite's internal electrostatic forces. This was quantitatively confirmed by X-ray photoelectron spectroscopy (XPS), which showed a clear correlation between increased surface Fe<sup>3+</sup>/Fe<sup>2+</sup> ratios and slower weathering kinetics. Furthermore, iron oxidation appeared to promote the formation of irregular mixed-layer structures (biotite–vermiculite layers), a plausible mechanistic consequence of heterogeneous structural cation redistribution. Comparative experiments of different initial compositions revealed that the CA biotite exhibited greater weathering resistance than the BR sample. This is because its distinct initial composition (higher halogen content and Fe<sup>3+</sup>/Fe<sup>2+</sup> ratio) enhanced K<sup>+</sup> retention. These findings highlight the decisive roles of structural iron oxidation and initial chemical composition in controlling biotite weathering rates and pathways and the formation of secondary mineral phases.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"285 ","pages":"Article 108163"},"PeriodicalIF":5.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171412","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}
Pub Date : 2026-06-01Epub Date: 2026-02-28DOI: 10.1016/j.precamres.2026.108067
Carina G. Lopes-Mira , Fernando F. Alkmim , Cristiano C. Lana
The basement of the São Francisco Craton in eastern Brazil records a complex history of growth and deformation that extends from the Paleoarchean up to the Orosirian Period. It hosts a segment of the Minas-Bahia Orogen, likely developed during the Orosirian assembly of the Central African block, a continental mass that would encompass the São Francisco-Congo, Borborema, Trans-Saharian, Rio de la Plata, and Kalahari shield provinces of South America and Africa. Aiming to unravel the tectonic scenarios of the Minas-Bahia Orogen generation, we conducted a stratigraphic, structural, geochemical, and geochronological study of the Rio Salitre belt of the Gavião microcontinent, the largest terrane of the Minas-Bahia Orogen exposed in the northern São Francisco craton. The Rio Salitre succession comprises a basal sedimentary unit (A), a middle volcano-sedimentary package (B), and an upper clastic sedimentary assemblage (C). Intruded by small granitic bodies and diabase dikes of unknown age, and unconformably covered by Meso- to Neoproterozoic strata, the Rio Salitre succession experienced two phases of deformation, a WNW-ESE contraction, followed by a left-lateral transtensional shearing that led to the development of a large-scale synformal keel, bound on all sides by basement uplifts. U-Pb zircon dating reveals Neoarchean (2666 ± 13 Ma) and Orosirian (1936 ± 21 Ma) maximum depositional ages, respectively, for Units A and C, and a Rhyacian depositional age of c. 2200 Ma for Unit B calc-alkaline to shoshonitic metatuffs. Our results point to a three-stage tectonic evolution of the Gavião microcontinent. Unit A represents the fill of an interior depocenter likely connected to a continental margin after 2666 Ma, whereas Unit B records its conversion into an extensional back-arc basin in the time interval of 2200 and 2100 Ma. Eventually, the Rio Salitre Basin evolved into a retro-foreland depocenter and received the clastic wedge of Unit C, accumulated after the collision of the various components of the Minas Bahia orogen. Our findings support a correlation between the Rio Salitre succession and classic Paleoproterozoic units of the São Francisco, Congo, and Kalahari cratons, thus favoring the existence of the Orosirian Central African paleocontinent.
{"title":"The Rio Salitre Volcano-Sedimentary Succession, São Francisco Craton, Eastern Brazil: Record of a Siderian-Orosirian tectonic cycle","authors":"Carina G. Lopes-Mira , Fernando F. Alkmim , Cristiano C. Lana","doi":"10.1016/j.precamres.2026.108067","DOIUrl":"10.1016/j.precamres.2026.108067","url":null,"abstract":"<div><div>The basement of the São Francisco Craton in eastern Brazil records a complex history of growth and deformation that extends from the Paleoarchean up to the Orosirian Period. It hosts a segment of the Minas-Bahia Orogen, likely developed during the Orosirian assembly of the Central African block, a continental mass that would encompass the São Francisco-Congo, Borborema, Trans-Saharian, Rio de la Plata, and Kalahari shield provinces of South America and Africa. Aiming to unravel the tectonic scenarios of the Minas-Bahia Orogen generation, we conducted a stratigraphic, structural, geochemical, and geochronological study of the Rio Salitre belt of the Gavião microcontinent, the largest terrane of the Minas-Bahia Orogen exposed in the northern São Francisco craton. The Rio Salitre succession comprises a basal sedimentary unit (A), a middle volcano-sedimentary package (B), and an upper clastic sedimentary assemblage (C). Intruded by small granitic bodies and diabase dikes of unknown age, and unconformably covered by Meso- to Neoproterozoic strata, the Rio Salitre succession experienced two phases of deformation, a WNW-ESE contraction, followed by a left-lateral transtensional shearing that led to the development of a large-scale synformal keel, bound on all sides by basement uplifts. U-Pb zircon dating reveals Neoarchean (2666 ± 13 Ma) and Orosirian (1936 ± 21 Ma) maximum depositional ages, respectively, for Units A and C, and a Rhyacian depositional age of c. 2200 Ma for Unit B calc-alkaline to shoshonitic metatuffs. Our results point to a three-stage tectonic evolution of the Gavião microcontinent. Unit A represents the fill of an interior depocenter likely connected to a continental margin after 2666 Ma, whereas Unit B records its conversion into an extensional back-arc basin in the time interval of 2200 and 2100 Ma. Eventually, the Rio Salitre Basin evolved into a <em>retro</em>-foreland depocenter and received the clastic wedge of Unit C, accumulated after the collision of the various components of the Minas Bahia orogen. Our findings support a correlation between the Rio Salitre succession and classic Paleoproterozoic units of the São Francisco, Congo, and Kalahari cratons, thus favoring the existence of the Orosirian Central African paleocontinent.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"437 ","pages":"Article 108067"},"PeriodicalIF":3.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147387445","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}
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