Eruption dynamics of Anak Krakatau volcano (Indonesia) estimated using photogrammetric methods

Research output: Contribution to journalResearch articleContributedpeer-review


  • Isabell Hochfeld - , University of Hamburg (First author)
  • Matthias Hort - , University of Hamburg (Author)
  • Ellen Schwalbe - , Chair of Photogrammetry (Author)
  • Tobias Dürig - , Institute of Earth Sciences, University of Iceland (Author)


Analyzing video data from an uncrewed aerial vehicle (UAV) of two short-lived dome building events at Anak Krakatau volcano (Indonesia), we determine vertical and horizontal movements of the dome surface prior to explosions, as well as initial eruption velocities and mass eruption rates via automated feature tracking and other photogrammetric methods. Initial eruption velocities and mass eruption rates are estimated as a proxy for eruptive strength. Eruptive strength is found to correlate with deformation magnitude, i.e., larger pre-explosion surface displacements are followed by both higher initial eruption velocities and mass fluxes. In accord with other studies, our observations can be explained by an overpressure underneath the dome’s surface. We assume that the dome seals the underlying vent efficiently, meaning that pre-explosion pressure build-up controls both deformation magnitude and eruptive strength. We support this assumption by a simple numerical model indicating that pre-explosion pressure increases between 8 and 16 MPa. The model further reveals that the two events vary significantly with respect to the importance of lateral visco-elastic flow for pressurization and deformation. The video sequences also show considerable variations in the gas release and associated deformation characteristics. Both constant and accelerating deformation is observed. Our case study demonstrates that photogrammetric methods are suitable to provide quantitative constraints on both effusive and explosive activity. Future work can build on our or similar approaches to develop automated monitoring strategies that would enable the observation and analysis of volcanic activity in near real time during a volcanic crisis.


Original languageEnglish
Article number73
Number of pages18
JournalBulletin of volcanology : official journal of the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI)
Early online date8 Jul 2022
Publication statusPublished - Aug 2022

External IDs

Scopus 85133650599


DFG Classification of Subject Areas according to Review Boards

Subject groups, research areas, subject areas according to Destatis


  • Photogrammetrie, Photogrammetrie, Vulkanismus, Bildanalyse, Bewegungsanalyse

Library keywords