{"title":"火星火成碎屑斜坡的形态及其在确定喷口-近端喷发动力学中的应用","authors":"B. Pieterek, T. J. Jones, L. Wilson","doi":"10.1029/2023JE008233","DOIUrl":null,"url":null,"abstract":"<p>High-resolution investigations of Late Amazonian volcanic landforms provide previously unrevealed insights into the dynamics of Martian volcanic eruptions. On Earth, the formation of vent-proximal accumulations of spatter deposits is attributed to low-intensity lava fountaining episodes representing eruptions on the very edge of explosive activity. Martian spatter deposits form small-scale volcanic landforms that are rarely reported, and thus the dynamics of Martian mafic explosive eruptions are still not fully constrained. We conducted high-resolution Context Camera-based mapping coupled with a stereo-pair-generated digital elevation model to reconstruct the eruptive history of a fissure system and its associated products south of Ascraeus Mons, Mars. The studied volcanic fissure clearly demonstrates both explosive and effusive deposits and, in addition, is spatially associated with a lava channel. For the first time, these observations allowed us to conduct a comparative analysis of vent-proximal volcanic products and reconstruct the late-stage eruption dynamics of a fissure system. We found that the spatial distribution of the pyroclastic (spatter) rampart along the fissure vent is heterogeneous and generated using dynamic eruption processes. Moreover, the lava channel fed from the fissure vent shows evidence of successive lava overspills whose emplacement was topographically controlled. These observations suggest that, in contrast to the general inference that Amazonian-age volcanism mainly involves effusive eruptions, explosive-origin landforms might have been overlooked. Therefore, we argue that high-resolution mapping of pyroclastic deposits may provide critical insights into understanding the dynamic nature of Martian fissure eruptions and explosive-associated volatile release during the last stages of eruptions.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9000,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The Morphology of Martian Pyroclastic Ramparts and Their Use in Determining Vent-Proximal Eruption Dynamics\",\"authors\":\"B. Pieterek, T. J. Jones, L. Wilson\",\"doi\":\"10.1029/2023JE008233\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>High-resolution investigations of Late Amazonian volcanic landforms provide previously unrevealed insights into the dynamics of Martian volcanic eruptions. On Earth, the formation of vent-proximal accumulations of spatter deposits is attributed to low-intensity lava fountaining episodes representing eruptions on the very edge of explosive activity. Martian spatter deposits form small-scale volcanic landforms that are rarely reported, and thus the dynamics of Martian mafic explosive eruptions are still not fully constrained. We conducted high-resolution Context Camera-based mapping coupled with a stereo-pair-generated digital elevation model to reconstruct the eruptive history of a fissure system and its associated products south of Ascraeus Mons, Mars. The studied volcanic fissure clearly demonstrates both explosive and effusive deposits and, in addition, is spatially associated with a lava channel. For the first time, these observations allowed us to conduct a comparative analysis of vent-proximal volcanic products and reconstruct the late-stage eruption dynamics of a fissure system. We found that the spatial distribution of the pyroclastic (spatter) rampart along the fissure vent is heterogeneous and generated using dynamic eruption processes. Moreover, the lava channel fed from the fissure vent shows evidence of successive lava overspills whose emplacement was topographically controlled. These observations suggest that, in contrast to the general inference that Amazonian-age volcanism mainly involves effusive eruptions, explosive-origin landforms might have been overlooked. Therefore, we argue that high-resolution mapping of pyroclastic deposits may provide critical insights into understanding the dynamic nature of Martian fissure eruptions and explosive-associated volatile release during the last stages of eruptions.</p>\",\"PeriodicalId\":16101,\"journal\":{\"name\":\"Journal of Geophysical Research: Planets\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.9000,\"publicationDate\":\"2024-05-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Geophysical Research: Planets\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1029/2023JE008233\",\"RegionNum\":1,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOCHEMISTRY & GEOPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Geophysical Research: Planets","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2023JE008233","RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
The Morphology of Martian Pyroclastic Ramparts and Their Use in Determining Vent-Proximal Eruption Dynamics
High-resolution investigations of Late Amazonian volcanic landforms provide previously unrevealed insights into the dynamics of Martian volcanic eruptions. On Earth, the formation of vent-proximal accumulations of spatter deposits is attributed to low-intensity lava fountaining episodes representing eruptions on the very edge of explosive activity. Martian spatter deposits form small-scale volcanic landforms that are rarely reported, and thus the dynamics of Martian mafic explosive eruptions are still not fully constrained. We conducted high-resolution Context Camera-based mapping coupled with a stereo-pair-generated digital elevation model to reconstruct the eruptive history of a fissure system and its associated products south of Ascraeus Mons, Mars. The studied volcanic fissure clearly demonstrates both explosive and effusive deposits and, in addition, is spatially associated with a lava channel. For the first time, these observations allowed us to conduct a comparative analysis of vent-proximal volcanic products and reconstruct the late-stage eruption dynamics of a fissure system. We found that the spatial distribution of the pyroclastic (spatter) rampart along the fissure vent is heterogeneous and generated using dynamic eruption processes. Moreover, the lava channel fed from the fissure vent shows evidence of successive lava overspills whose emplacement was topographically controlled. These observations suggest that, in contrast to the general inference that Amazonian-age volcanism mainly involves effusive eruptions, explosive-origin landforms might have been overlooked. Therefore, we argue that high-resolution mapping of pyroclastic deposits may provide critical insights into understanding the dynamic nature of Martian fissure eruptions and explosive-associated volatile release during the last stages of eruptions.
期刊介绍:
The Journal of Geophysical Research Planets is dedicated to the publication of new and original research in the broad field of planetary science. Manuscripts concerning planetary geology, geophysics, geochemistry, atmospheres, and dynamics are appropriate for the journal when they increase knowledge about the processes that affect Solar System objects. Manuscripts concerning other planetary systems, exoplanets or Earth are welcome when presented in a comparative planetology perspective. Studies in the field of astrobiology will be considered when they have immediate consequences for the interpretation of planetary data. JGR: Planets does not publish manuscripts that deal with future missions and instrumentation, nor those that are primarily of an engineering interest. Instrument, calibration or data processing papers may be appropriate for the journal, but only when accompanied by scientific analysis and interpretation that increases understanding of the studied object. A manuscript that describes a new method or technique would be acceptable for JGR: Planets if it contained new and relevant scientific results obtained using the method. Review articles are generally not appropriate for JGR: Planets, but they may be considered if they form an integral part of a special issue.