Bulletin of Volcanology

, 77:15

Experiments with vertically and laterally migrating subsurface explosions with applications to the geology of phreatomagmatic and hydrothermal explosion craters and diatremes

  • Greg A. Valentine
  • Alison H. Graettinger
  • Élodie Macorps
  • Pierre-Simon Ross
  • James D. L. White
  • Erika Döhring
  • Ingo Sonder
Research Article

DOI: 10.1007/s00445-015-0901-7

Cite this article as:
Valentine, G.A., Graettinger, A.H., Macorps, É. et al. Bull Volcanol (2015) 77: 15. doi:10.1007/s00445-015-0901-7

Abstract

We present results of experiments that use small chemical explosive charges buried in layered aggregates to simulate the effects of subsurface hydrothermal and phreatomagmatic explosions at varying depths and lateral locations, extending earlier experimental results that changed explosion locations only along a vertical axis. The focus is on the resulting crater size and shape and subcrater structures. Final crater shapes tend to be roughly circular if subsurface explosion epicenters occur within each other’s footprints (defined as the plan view area of reference crater produced by a single explosion of a given energy, as predicted by an empirical relationship). Craters are elongate if an epicenter lies somewhat beyond the footprint of the previous explosion, such that their footprints overlap, but if epicenters are too far apart, the footprints do not overlap and separate craters result. Explosions beneath crater walls formed by previous blasts tend to produce inclined (laterally directed) ejecta jets, while those beneath crater centers are vertically focused. Lateral shifting of explosion sites results in mixing of subcrater materials by development of multiple subvertical domains of otherwise pure materials, which progressively break down with repeated blasts, and by ejection and fallback of deeper-seated material that had experienced net upward displacement to very shallow levels by previous explosions. A variably developed collar of material that experienced net downward displacement surrounds the subvertical domains. The results demonstrate key processes related to mixing and ejection of materials from different depths during an eruptive episode at a maar-diatreme volcano as well as at other phreatomagmatic and hydrothermal explosion sites.

Keywords

Phreatomagmatic Hydrothermal explosion Crater Ejecta Diatreme Maar Phreatic Kimberlite pipe 

Supplementary material

Online Resource 1

High-speed video (300 frames per second) of blast 3 at pad 4. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 10,000 kb)

Online Resource 2

High-speed video (300 frames per second) of blast 1 at pad 2. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 10,952 kb)

Online Resource 3

High-speed video (300 frames per second) of blast 4 at pad 2. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 10,447 kb)

Online Resource 4

High-speed video (300 frames per second) of blast 1 at pad 3. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 10,526 kb)

Online Resource 5

High-speed video (300 frames per second) of blast 1 at pad 1. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 11,382 kb)

Online Resource 6

High-speed video (300 frames per second) of blast 5 at pad 1. Playback speed is 30 frames per second (slowed compared to real time by a factor of ten). (MOV 11,303 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Greg A. Valentine
    • 1
  • Alison H. Graettinger
    • 1
  • Élodie Macorps
    • 1
    • 2
  • Pierre-Simon Ross
    • 3
  • James D. L. White
    • 4
  • Erika Döhring
    • 5
  • Ingo Sonder
    • 1
  1. 1.Department of Geology and Center for Geohazards StudiesState University of New YorkBuffaloUSA
  2. 2.Laboratoire Magmas et Volcans, Observatoire de Physique du Globe de Clermont-FerrandUniversité Blaise PascalClermont-FerrandFrance
  3. 3.Institut National de la Recherche ScientifiqueCentre Eau Terre EnvironnementQuébecCanada
  4. 4.Geology DepartmentUniversity of OtagoDunedinNew Zealand
  5. 5.Institut Polytechnique LaSalle BeauvaisBeauvaisFrance

Personalised recommendations