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Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOV Ekaterina V.LEBEDEVA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data available.The authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric characteristics.It has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal activity.While lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric indicators.It was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their basins.The volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous processes.For the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were calculated.Repeated observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 years.This analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their study.The results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying other volcanic lakes.

关键词： Volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands

Volcanically Driven Terrestrial Environmental Perturbations during the Carnian Pluvial Episode in the Eastern Tethys

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 753-770页

作者： Naveed Ur RAHMAN XIAN Benzhong FANG Linhao CHEN Sirui CHEN Peng Zaheen ULLAH WANG Pengyu National Key Laboratory of Petroleum Resources and Engineering Beijing 102249China College of Geosciences China University of PetroleumBeijing 102249China Centre for Earth and Space Sciences University of SwatSwat 19120Pakistan

The Carnian Pluvial Episode(CPE)fingerprints global environmental perturbations and biological extinction on land and oceans and is potentially linked to the Wrangellia Large Igneous Province(LIP).However,the correlation between terrestrial environmental changes and Wrangellia volcanism in the Ordos Basin during the CPE remains poorly understood.Records of negative carbon isotopic excursions(NCIEs),mercury(Hg),Hg/TOC,and Hg enrichment factor(HgEF)from oil shales in a large-scale terrestrial Ordos Basin in the Eastern Tethys were correlated with marine and other terrestrial successions.The three significant NCIEs in the study section were consistently correlated with those in the CPE successions of Europe,the UK,and South and North China.The U-Pb geochronology indicates a Ladinian-Carnian age for the Chang 7 Member.A comprehensive overview of the geochronology,NCIE correlation,and previous bio-and chronostratigraphic frameworks shows that the Ladinian-Carnian boundary is located in the lower part of Chang 7 in the Yishicun section.HgEF may be a more reliable proxy for tracing volcanic eruptions than the Hg/TOC ratio because the accumulation rates of TOC content largely vary in terrestrial and marine successions.The records of Hg,Hg/TOC,HgEF,and NCIEs in the Ordos Basin aligned with Carnian successions worldwide and were marked by similar anomalies,indicating a global response to the Wrangellia LIP during the CPE.Anoxia,a warm-humid climate,enhancement of detrital input,and NCIEs are synchronous with the CPE interval in the Ordos Basin,which suggests that the CPE combined with the regional Qinling Orogeny should dominate the enhanced rate of terrigenous input and paleoenvironmental evolution in the Ordos Basin.

关键词： Chang 7 Member oil shale Carnian Pluvial Episode volcanism environmental perturbations

The formation and growth mechanisms of young back-arc spreading ridges from high-resolution bathymetry:The Marsili Seamount(Tyrrhenian Sea,Italy)

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Geoscience Frontiers 2024年第1期15卷 325-338页

作者： Eugenio Nicotra Salvatore Passaro Guido Ventura Dipartimento di Biologia Ecologia e Scienze della Terra Universitàdella Calabria87036 Arcavacata di RendeCosenzaItaly Istituto di Scienze Marine CNR 80133 NapoliItaly Istituto Nazionale di Geofisica e Vulcanologia 00143 RomaItaly Istituto per lo Studio degli impatti Antropici e Sostenibilitáin ambiente marino CNR 91026 Capo GranitolaTrapaniItaly

The formation and growth mechanisms of Mid-Ocean Ridges(MOR)are relatively well known,whereas those of back-arc spreading ridges are comparatively less known because geophysical,geochemical,and morphological data are scarce and of low density.Here we present a high-resolution bathymetry of the Marsili Seamount(MS;1 Ma-3 ka),which represents the inflated spreading ridge of the 2 Ma old Marsili back-arc basin associated to the subduction of the Ionian Sea below the Calabrian Arc and Tyrrhenian Sea.MS is 70 km long,30 km wide,and its height reaches about 3000 m from surrounding seafloor.Our new digital bathymetric model has a 5 m grid cell size resolution and covers the MS bathymetry from-1670 mbsl to the top at-491 mbsl.We conduct morphometric and morphological analyses of the bathymetry and recognize landforms due to volcanic,tectonic,hydrothermal and gravity processes.MS consists of volcanoes related to fissural and central-type activity,this latter located at the northern and southern tips of the main dike swarms.Dike swarms represent the surface expression of different ridge segments whose strikes are controlled by the larger scale back-arc spreading processes and by the local occurrence of an active hydrothermal field.This latter develops in a flat area between two partly overlapping ridge segments where historical volcanism and extensional processes concentrate.Such ridges represent the embryonic stage of the formation of transform-like faults.Central volcanoes,the northern of which is characterized by a caldera,form at the tips of MS because the decrease in width of the major volcanic fissures promotes vent localization associated with the formation of sill-like reservoirs from which central-type vents may develop.Gravity processes affecting the MS flanks are due to shallow seafloor sliding.Caldera collapses affecting the northernmost central-type polygenic volcano must be included in the evaluation of the hazard related to potential tsunami.Inward dipping faults characterize the MS eastern flank suggesting

关键词： Back-arc spreading ridge Morphology Tectonics volcanism Marsili seamount

volcanism in the Solar System

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Science China Earth Sciences 2023年第11期66卷 2419-2440页

作者： Long XIAO Jun HUANG Zhiyong XIAO Chao QI Yuqi QIAN School of Earth Sciences China University of GeosciencesWuhan 430074China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Volcanic activity is the main process for heat-material exchange and circulation for differentiated planets. All terrestrial planets in the Solar System, the Moon, the satellites of giant planets, and the dwarf planets once experienced or are currently experiencing volcanic activities. This paper summarized the volcanism(main volcanic features and their formation) on the Moon, Mars, Venus, and Mercury in the inner Solar System, volcanism and cryovolcanism on satellites(Io, Europa,Enceladus) of giant planets, as well as volcanism on dwarf planets including Cere in the main asteroid belt and Pluto in the Kuiper belt. This work shows volcanism in the Solar System is driven by various factors, forming abundant volcanic landforms.It has significant meanings to compare volcanism happening on different planets using comparative planetology approaches for a better understanding of volcanism, the planetary habitability, and the information contained on the origin and evolution of planets in the Solar System.

关键词： volcanism Terrestrial planets Planetary evolution Solar System

volcanism Pacing Slumping Gravity Flow Deposits during the Late Carboniferous in the Southern Margin of the Junggar Basin,China

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地质学报:英文版 2023年第5期97卷 1422-1450页

作者： LI Shixin ZHANG Tingshan ZHANG Xi LIANG Zeliang JI Dongsheng Mihai Emilian POPA YONG Jinjie LUO Jinyu ZENG Jianli ZHU Haihua School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Natural Gas Geology Key Laboratory of Sichuan Province Southwest Petroleum UniversityChengdu 610500China PetroChina Xinjiang Oilfield Company KaramayXinjiang 834000China Faculty of Geology and Geophysics University of BucharestBucharest 010041Romania

Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years.This study discusses the co-evolution of volcanism and deep-water gravity flow deposits at the southern margin of the Junggar Basin,based on petrology,geochronology and geochemical analyses.The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism,resulting in the formation of slumping gravity flows.The occurrence of volcanic beds in the slump deposits confirm that synchronous volcanism likely affected sediment instability,triggering gravity flows.The Th/Yb,Ta/Yb and Th/Ta elemental ratios,U-Pb ages of detrital zircons and paleocurrent directions indicate that the North Tianshan(NTS)island arc represents the provenance of the Qianxia Formation.Moreover,statistical data on the pyroclastic components in the gravity flow deposits reveal an intensity index of volcanism,indicating that volcanism is strongly related to gravity flow deposits,especially in terms of the type and distribution of the deposits.A model for volcanically-triggered deep-water gravity flow deposits is established,in order to provide a more in-depth understanding of the co-evolution of volcanism and gravity flow deposits within the depositional setting of the late Paleozoic NTS oceanic subduction margin in the Junggar Basin.

关键词： volcanism trigger gravity flow deposits island arc Qianxia Formation Junggar Basin

Revisiting the mechanisms of mid-Tertiary uplift of the NE Tibetan Plateau

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National Science Review 2023年第4期10卷 169-190页

作者： Hong-Hong Wei Guo-Li Wu Lin Ding Long-Gang Fan Lin Li Qing-Ren Meng State Key Laboratory of Tibetan Plateau Earth System Environment and Resources (TPESER) Institute of Tibetan Plateau Research Chinese Academy of Sciences Institute of Geomechanics Chinese Academy of Geological Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Department of Geosciences University of Arizona University of Chinese Academy of Sciences

Contrasting views exist on timing and mechanisms of Tertiary crustal uplift in the NE Tibetan Plateau based on different approaches, with many models atributing surface uplift to crustal shortening. We carry out a comprehensive investigation of mid-Tertiary stratigraphy, sedimentology, and volcanism in the West Qinling, Hoh Xil and Qaidam basin, and the results challenge previous views. It was held that the discordance between Oligocene and Miocene strata is an angular unconformity in the West Qinling, but our field observations show that it is actually a disconformity, indicative of vertical crustal uplifting rather than crustal shortening at the Oligocene to Miocene transition. Widespread occurrence of synsedimentary normal faults in mid-Tertiary successions implicates supracrustal stretching. Miocene potassic–ultrapassic and mafic–ultramafic volcanics in the Hoh Xil and West Qinling suggest a crucial role of deep thermomechanical processes in generating crust-and mantle-sourced magmatism. Also noticeable are the continuity of mid-Tertiary successions and absence of volcanics in the Qaidam basin. Based on a holistic assessment of stratigraphic–sedimentary processes, volcanic petrogenesis, and spatial variations of lithospheric thicknesses, we speculate that small-sale mantle convection might have been operating beneath northeast Tibet in the mid-Tertiary. It is assumed that northward asthenospheric flow was impeded by thicker cratonic lithosphere of the Qaidam and Alxa blocks, thereby leading to edge convection. The edge-driven convection could bring about surface uplift, induce supracrustal stretching, and trigger vigorous volcanism in the Hoh Xil and West Qinling in the mid-Tertiary period. This mechanism satisfactorily explains many key geologic phenomena that are hardly reconciled by previous models.

关键词： NE Tibetan Plateau mid-Tertiary unconformity volcanism edge convection

Cretaceous basin evolution in northeast Asia:tectonic responses to the paleo-Pacific plate subduction

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National Science Review 2022年第1期9卷 144-161页

作者： Qing-Ren Meng Zhong-He Zhou Ri-Xiang Zhu Yi-Gang Xu Zheng-Tang Guo State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Innovation Academy for Earth Science Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Cenozoic Geology and Environment Chinese Academy of Sciences

Cretaceous rift basin evolution was an important part of the tectonic history of northeast Asia in the late Mesozoic.Three types of rift basins are identified—active,passive and wide rift basins—and they developed in different regions.Passive rift basins in the eastern North China craton are thought to be the consequence of crustal stretching and passive asthenospheric upwelling.Wide rift basins in the eastern Central Asian orogen are assumed to originate from gravitational collapse of the thickened and heated orogenic crust.Active rift basins in the northern North China craton are attributed to uprising of asthenospheric materials along a lithospheric-scale tear fault.Slab tearing of the sub ducting paleo-Pacific plate is postulated and well explains the spatial distribution of different types of rift basins and the eastward shifting of magmatism in the northern North China craton.The Late Cretaceous witnessed a period of mild deformation and weak magmatism,which was possibly due to kinematic variation of the paleo-Pacific plate.

关键词： NE Asia Cretaceous rift basin volcanism paleo-Pacific plate

Sedimentary features and sequence stratigraphy of the successions around the Carboniferous-Permian boundary in the Ordos Basin:links to glacial and volcanic impacts

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Journal of Palaeogeography 2023年第3期12卷 358-383页

作者： Zhong-Shuai Hou Shi-Yue Chen Zhao Liang Hebei Key Laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuang 050031China Interdisciplinary Science Research Institute Hebei GEO UniversityShijiazhuang 050031China School of Geosciences China University of PetroleumQingdao 266580China

The sedimentary successions around the Carboniferous-Permian boundary(CPB)in the Ordos Basin were investigated using extensive outcrop,borehole,well logging,thin section,and geochemistry data to study sedimentary and sequence stratigraphic responses to glaciation and volcanism in paleotropical transitional strata.Within the studied interval,five distinct lithofacies have been identified,including bauxite,coal,and carbonaceous shale(No.8+9 coal seams),sandstone(Qiaotou),limestone(Baode),and mudstone,which can be classified into three lithofacies associations.The most complete lithofacies associ-ation is composed of bauxite,coal,carbonaceous shale,sandstone,limestone/mudstone or their combinations from the bottom to the top,while coal and carbonaceous shale,as well as sandstone,are absent locally,resulting in the formation of the other two types of lithofacies associations.The occurrence of bauxite in-dicates shelf exposure and weathering,the occurrence of coal and carbonaceous shale indicates swampiness of the shelf,and the occurrence of sandstone reveals river rejuvenation;all of these are thought to be sedimentary responses to the transcontinental glacier expansion in Gondwana around the CPB.The presence of limestone and mudstone indicates carbonate platform and lagoon deposition,respectively,in the context of the earliest Asselian transgression caused by volcanism-induced glacier melting.The lithofacies associations record the regressive-transgressive cycles that occurred because of glaciation and volcanism near the CPB.The top surface of bauxite can be used as a sequence boundary,while the lowstand systems tract consists of the No.8+9 coal seams and the Qiaotou sandstone,and the transgressive systems tract consists of the overlying Baode limestone and laterally equivalent mudstone.The lowstand systems tract,which contains source rock and hydrocarbon reservoirs,and the overlying transgressive systems tract,which serves as cap rock,form an excellent source-reservoir-seal combination.

关键词： Glaciation volcanism Incised valley Sequence stratigraphy Ordos basin

Cenozoic volcanism and lithospheric tectonic evolution in Qiangtang area, northern Qinghai-Tibet Plateau

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Science China Earth Sciences 2005年第7期48卷 1011-1024页

作者： CHI Xiaoguo LI Cai JIN Wei College of Earth Sciences Jilin University Changchun 130061 China College of Earth Sciences Jilin University Changchun 130061 China College of Earth Sciences Jilin University Changchun 130061 China

Following the collision between the Indian and Eurasian plates, the Cenozoic vol- canic activities are rather frequent in the Qiangtang area of northern Qinghai-Tibet Plateau. They can be divided into four series: alkaline basalt series, high-K calc-alkaline series, shoshonitic series and peralkaline potassic-ultrapotassic series. Geochemical data suggest that the magma sources of Cenozoic volcanic rocks have transferred from spinel lherzolite mantle in the early stage to garnet peridotite enriched mantle (EM2) in the later stage. The high Mg# number and extremely high Cr-Ni-Co abundance of high-K calc-alkaline and shoshonitic series andesites in the Qiangtang area indicate that the primary magma might be derived from subduction of conti- nent lithosphere from the Lhasa block. Incompatible element ratios of La/Rb, Zr/Rb, Rb/Nb, K/Nb, Pb/La and K/La of peralkaline potassic-ultrapotassic series lavas in northern Qinghai-Tibet Pla- teau are lower than island arc volcanic rocks and higher than and similar to oceanic island ba- salts. This signature indicates that the primary magma derive from a paleo-mantle wedge inter- fused by fluids derived from asthenosphere and/or subducted mantle lithosphere. But the above element ratios of ultrapotassic lavas in southern Tibet and ultrapotassic lamprophyres in eastern Tibet are higher than and similar to island arc volcanic rocks, which means that the primary magma sources contained a large quantity of crust contaminant from fluids and/or melts derived from subducted continent lithosphere. The studies result supports that the indian continental lithosphere has underthrust beneath Tibet to about the middle of the plateau, and Eurasian (Qaidam basin) mantle lithosphere has underthrust beneath the Qiangtang area of northern Tibet Plateau. In the paper we demonstrate further that the pulsing cycles of potassic-ultrapotassic volcanism of the Qinghai-Tibet Plateau result from an asthenospher pulsing upwelling caused by the intraplate subduction and the stress relaxation in hinterlan

关键词： Cenozoic volcanism magmatic source lithosphere tectonic evolution northern Tibet.