Fibre Optic Remote Displacement Sensor for Seismic Events at High Temperature

  • W. Ecke
  • K.-H. Jäckel
  • P. Pfeifer
  • J. Schauer
  • R. Willsch

Abstract

Recent geophysical research includes measurement of seismic events in non-trivial surroundings. Seismic sensors have to be installed in very deep boreholes as well as in volcanic regions at measuring sites with temperatures above 250°C and with several km of transmission lines between sensor and signal processing. The application in a three-dimensional seismic network requires detection of vibration amplitudes Δs=0.1nm. 100μm at frequencies 0.1Hz..30Hz. Under these conditions, interferometric detection and signal transmission using optoelectronic and fibre-optic components of photonic technology seems to be the only possibility to perform long-term measurement of seismic waves. In this paper, results are presented concerning high-temperature parameters of fibre-optic key components and interferometer construction, signal processing for evaluation of optical phase, and first results of the sensor test.

Keywords

Signal Scheme Wavelength Modulation Michelson Interferometer Optical Phase Deep Borehole 
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.

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • W. Ecke
    • 1
  • K.-H. Jäckel
    • 2
  • P. Pfeifer
    • 1
  • J. Schauer
    • 1
  • R. Willsch
    • 1
  1. 1.Institut für Physikalische Hochtechnologie (IPHT)JenaGermany
  2. 2.GeoForschungsZentrum PotsdamPotsdamGermany

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