pure and applied geophysics

, Volume 121, Issue 1, pp 27–38 | Cite as

Icequakes and glacier motion: The hans glacier, spitsbergen

  • Artur Cichowicz
Article
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Abstract

The recording of glacier icequakes has been carried out on the Hans glacier, Spitsbergen. The icequakes have been connected with the formation of open cracks. The energy of the main group of icequakes has ranged from 0.01 J to 6 J, their seismic moment being from 0.5 · 1014 dyne · cm to 26 · 1014 dyne · cm. The nonelastic volume increase corresponding to each crack has ranged from 0.2 · 10−2 m3 to 8.8 · 10−2 m3. The stresses released due to extensional faulting ranged from 25N/m2 to 500 N/m2; these values are so small that they suggest an incomplete release of the medium. The contribution into the glacier flow rate of the deformation in the surface glacier layer due to extensional faulting is lower by 2 to 3 orders of magnitude than the total plastic deformation associated with the ice creeping.

Key words

Icequake Tensile fracture 
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Copyright information

© Birkhäuser-Verlag 1983

Authors and Affiliations

  • Artur Cichowicz
    • 1
  1. 1.Institute of GeophysicsPolish Academy of SciencesWarsawPoland

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