Summary
We discuss the design principles involved in long baseline fluid tiltmeters and describe the construction and operation of a 240 m long half-filled tube tiltmeter using laser-interferometer end-transducers. The prototype operates in a warehouse at Suffern, NY and is subject to large ambient temperature changes (± 5°C). Several important design features are identified that enable thermal and random noise to be minimised: these include the incorporation of a central reservoir of large area in the system to reduce thermal effects and to provide decoupling between the end transducers, the use of predictive filtering in data analysis to suppress end-mount noise and the use of porous linings in end transducers to eliminate adhesion tension. It is shown that a symmetrical tiltmeter with a central reservoir of large surface area can be used to monitor flexure of the Earth’s surface in addition to tilt. The noise level of the 240 m tiltmeter is approximately 10-8 radians at daily periods and 10-7 radians at periods between a week and a year. The resolution of the present design is limited by the wavelength of light to 4 x 10-9 radians.
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References
Sacks, I. S., Borehole strainmeters, USGS Conf. Measurement of Ground Strain Phenomena Related to Earthquake Prediction, Carmel, Sept, 7-9, 1978.
Takahasi, R., Preliminary report on the observation of the tilting of the Earth’s crust with a pair of water pipes, Bull. Earthq. Res. Inst., Univ. Tokyo, 8, 143–152, 1931.
Hagiwara, T., and J. Yamada, Changes in inclination of the Earth’s surface observed with the water-tube tiltmeter, Spec. Bull. Earthq. Res. Inst., Univ. Tokyo, 5, 179–185, 1947.
Hagiwara, T., and T. Rikitake, Observation of the deformation of the Earthd’s surface in the vicinity of the epicenters of the Imaichi earthquake, Bull. Earthq. Res. Inst., Univ. Tokyo, 4, 435–441, 1950.
Davis, P., K. Evans, J. Horsfall, and G. King, Long baseline tilt and strain measurement, Recent Crustal Movement Symposium, Stamford, August 1977.
Horsfall, J. A. C., A new geophysical tiltmeter, Ph.D. Thesis, Cambridge Univ., 1977.
Karcz, I., J. Morreale, and F. Porebski, Assessment of benchmark credibility in the study of recent crustal movements, Tectonophysics, 33, 1–6, 1976.
Gagnon, P., J. Jobin, and R. Sanchez, Evaluation and monitoring of long-term tilting of the crust by geometric levelling, Canad. Geophys. Union (Abstract), May 15-17, London, Ontario, 1978.
Michelson, A. A., and H. G. Gale, The rigidity of the Earth, Astrophys. J., 50, 330–345, 1919.
Egedal, J., and J. E. Fjeldstad, Observations of tidal motions of the Earth’s crust made at the Geophysical Institute, Bergen Geofysiske Publikjoner, 11, 4, Norwegian Acad. Sci., 1937.
Egedal, J., On the application of the hydrostatic method to levelling and to determination of vertical movements in the Earth’s crust, Danish Meteorological Inst. Pub. 10, 1–64, 1947.
Kasahara, K., Earthquake fault studies in Japan, Phil. Trans. R. Soc. Lond A-274, 287–296, 1973.
Bower, D. R., and N. Courtier, Long baseline tilt observations in a mine near Ottawa, Canad. Geophys. Union Meeting, London, Ontario, May 13-17, 1978.
Plumb, R., R. Bilham, and J. Beavan, A stable long baseline fluid tiltmeter for tectonic studies, USGS Conf. Measurement of Ground Strain Phenomena Related to Earthquake Prediction, Carmel, Sept. 7-9, 1978.
Michelson, A. A., Preliminary results of measurements of the rigidity of the Earth, Astrophys. J., 39, 105–138, 1914.
Haalck, H., Ein quecksilberneigungsmesser von hoher empfindlich-kier, Z. Geophysik, 8, 256–271, 1932.
Eaton, J. P., A portable water tube tiltmeter, Bull. Seism. Soc. Am., 49, 301–306, 1959.
Eto, T., A recording water tube tiltmeter, Bull. Pis. Prev. Res. Inst., 15,3, 98, 21-59, 1966.
Kääriäinen, J., Über die 50 m lange rohrlibelle zur Untersuchung der neigung der erdkruste, Rept. Finnish Geod. Inst. ISBN 951-711-002-2, Helsinki, 1973.
Bower, D. R., A sensitive water-level tiltmeter, Phil. Trans. R. Soc. Lond A-274, 223–226, 1973.
Zharimov, N. A., Izvestia Earth Physics, Akad. Nauk. USSR, 3, 83–90, 1975.
Weber, J. R., and M. Erdelyi, Ice and ocean tilt measurements in the Beaufort Sea, J. Glaciology, 17, 61–71, 1976.
Huggett, G. R., L. E. Slater, and G. Pavlis, Precision levelling with a two fluid tiltmeter, Geophys. Res. Lett., 3, 754–756, 1976.
Beavan, J., and R. Bilham, Thermally induced errors in fluid tube tiltmeters, J. Geophys. Res., 82, 5699–5704, 1977.
Horsfall, J. A. C., and G. C. P. King, A new geophysical tilt-meter, Nature, 274, 675–676, 1978.
Beavan, R. J., and N. R. Goulty, Earth strain observations made with the Cambridge laser strainmeter, Geophys. J. R. astr. Soc, 48, 293–305, 1977.
Harrison, J. C., Cavity and topographic effects on tilt and strain measurement, J. Geophys. Res., 81, 319–328, 1976.
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Bilham, R., Plumb, R., Beavan, J. (1979). Design Considerations in an Ultra-Stable, Long Baseline Tiltmeter — Results from a Laser Tiltmeter. In: Vogel, A. (eds) Terrestrial and Space Techniques in Earthquake Prediction Research. Vieweg+Teubner Verlag, Wiesbaden. https://doi.org/10.1007/978-3-322-86323-2_15
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DOI: https://doi.org/10.1007/978-3-322-86323-2_15
Publisher Name: Vieweg+Teubner Verlag, Wiesbaden
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