Borehole observations of continuous strain and fluid pressure

  • Evelyn A. Roeloffs
  • Alan T. Linde
Part of the Springer Praxis Books book series (PRAXIS)


Strain is expansion, contraction, or distortion of the volcanic edifice and surrounding crust. As a result of magma movement, volcanoes may undergo enormous strain prior to and during eruption. Global Positioning System (GPS) observations can in principle be used to determine strain by taking the difference between two nearby observations and dividing by the distance between them. Two GPS stations 1 km apart, each providing displacement information accurate to the nearest millimeter, could detect strain as small as 2 mm km-1, or 2 × 10-6. It is possible, however, to measure strains at least three orders of magnitude smaller using borehole strainmeters. In fact, it is even possible to measure strains as small as 10-8 using observations of groundwater levels in boreholes.


Global Position System Groundwater Level Volumetric Strain Earth Tide Water Level Change 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Praxis Publishing Ltd, Chichester, UK 2007

Authors and Affiliations

  • Evelyn A. Roeloffs
  • Alan T. Linde

There are no affiliations available

Personalised recommendations