The in-flight deformation of pyroclasts: insights from analogue experiments.

Saved in:
Bibliographic Details
Title: The in-flight deformation of pyroclasts: insights from analogue experiments.
Authors: Ogbuagu, Chiedozie C.1,2,3 (AUTHOR) Chiedozie.Ogbuagu@liverpool.ac.uk, Jones, Thomas J.4 (AUTHOR)
Source: Bulletin of Volcanology. May2025, Vol. 87 Issue 5, p1-20. 20p.
Subject Terms: *Weber number, *Deformation potential, *Earth sciences, *Air flow, *Dimensionless numbers
Abstract: Explosive eruptions of basaltic and other low-viscosity, magmas are widespread and mostly characterised by lava fountains and jets that produce a diverse array of pyroclasts. Considering the hazardous nature and potentially long duration of most low-viscosity eruptions, understanding the eruption dynamics and range in pyroclast characteristics (i.e., their shape and size) remains an important goal. Analogue experiments provide a robust means of studying the same dynamic processes within a controlled laboratory environment. In this study, we used scaled analogue experiments to investigate the in-flight deformation of pyroclasts. A total of 30 experiments, grouped into three different experiment sets, were conducted to cover a range of pyroclast properties (e.g., viscosity) and eruption conditions. Analogue fluid droplets were released at various heights in the presence of a controlled background air flow, replicating pyroclast transport within a fountain or jet after primary magmatic fragmentation. High-speed videography and accompanying image analysis documented any change in the droplet shape during flight. Droplets falling from constant height, with increasing background gas velocities increasingly deformed, progressing from regimes of positive and negative deformation, through oscillatory deformation to bag-stamen deformation, at dimensionless Weber numbers (We) ranging from 0.52 to 8.26. This study, through an experimentally validated in-flight deformation map, illustrates that all explosive eruptions of low viscosity magma (e.g., carbonatites, kimberlites, basanites, basalts) are susceptible to in-flight pyroclast deformation and potential secondary fragmentation. These processes need to be considered when examining pyroclasts within the stratigraphic record and inverting textures for dynamic eruption processes. [ABSTRACT FROM AUTHOR]
Database: Energy & Power Source
Full text is not displayed to guests.
FullText Links:
  – Type: pdflink
Text:
  Availability: 1
Header DbId: enr
DbLabel: Energy & Power Source
An: 185280429
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: The in-flight deformation of pyroclasts: insights from analogue experiments.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Ogbuagu%2C+Chiedozie+C%2E%22">Ogbuagu, Chiedozie C.</searchLink><relatesTo>1,2,3</relatesTo> (AUTHOR)<i> Chiedozie.Ogbuagu@liverpool.ac.uk</i><br /><searchLink fieldCode="AR" term="%22Jones%2C+Thomas+J%2E%22">Jones, Thomas J.</searchLink><relatesTo>4</relatesTo> (AUTHOR)
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Bulletin+of+Volcanology%22">Bulletin of Volcanology</searchLink>. May2025, Vol. 87 Issue 5, p1-20. 20p.
– Name: Subject
  Label: Subject Terms
  Group: Su
  Data: *<searchLink fieldCode="DE" term="%22Weber+number%22">Weber number</searchLink><br />*<searchLink fieldCode="DE" term="%22Deformation+potential%22">Deformation potential</searchLink><br />*<searchLink fieldCode="DE" term="%22Earth+sciences%22">Earth sciences</searchLink><br />*<searchLink fieldCode="DE" term="%22Air+flow%22">Air flow</searchLink><br />*<searchLink fieldCode="DE" term="%22Dimensionless+numbers%22">Dimensionless numbers</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Explosive eruptions of basaltic and other low-viscosity, magmas are widespread and mostly characterised by lava fountains and jets that produce a diverse array of pyroclasts. Considering the hazardous nature and potentially long duration of most low-viscosity eruptions, understanding the eruption dynamics and range in pyroclast characteristics (i.e., their shape and size) remains an important goal. Analogue experiments provide a robust means of studying the same dynamic processes within a controlled laboratory environment. In this study, we used scaled analogue experiments to investigate the in-flight deformation of pyroclasts. A total of 30 experiments, grouped into three different experiment sets, were conducted to cover a range of pyroclast properties (e.g., viscosity) and eruption conditions. Analogue fluid droplets were released at various heights in the presence of a controlled background air flow, replicating pyroclast transport within a fountain or jet after primary magmatic fragmentation. High-speed videography and accompanying image analysis documented any change in the droplet shape during flight. Droplets falling from constant height, with increasing background gas velocities increasingly deformed, progressing from regimes of positive and negative deformation, through oscillatory deformation to bag-stamen deformation, at dimensionless Weber numbers (We) ranging from 0.52 to 8.26. This study, through an experimentally validated in-flight deformation map, illustrates that all explosive eruptions of low viscosity magma (e.g., carbonatites, kimberlites, basanites, basalts) are susceptible to in-flight pyroclast deformation and potential secondary fragmentation. These processes need to be considered when examining pyroclasts within the stratigraphic record and inverting textures for dynamic eruption processes. [ABSTRACT FROM AUTHOR]
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=enr&AN=185280429
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1007/s00445-025-01814-3
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 20
        StartPage: 1
    Subjects:
      – SubjectFull: Weber number
        Type: general
      – SubjectFull: Deformation potential
        Type: general
      – SubjectFull: Earth sciences
        Type: general
      – SubjectFull: Air flow
        Type: general
      – SubjectFull: Dimensionless numbers
        Type: general
    Titles:
      – TitleFull: The in-flight deformation of pyroclasts: insights from analogue experiments.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Ogbuagu, Chiedozie C.
      – PersonEntity:
          Name:
            NameFull: Jones, Thomas J.
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 05
              Text: May2025
              Type: published
              Y: 2025
          Identifiers:
            – Type: issn-print
              Value: 02588900
          Numbering:
            – Type: volume
              Value: 87
            – Type: issue
              Value: 5
          Titles:
            – TitleFull: Bulletin of Volcanology
              Type: main
ResultId 1