Measurements and interpretations of tilt-strain gauges in seismically active areas

Earth Science Reviews

Volumn 47, Issue 3-4, 1999, Pages 151-187

  Zadro, Maria ^a   Braitenberg, Carla ^a  

^a UNIVERSITY OF TRIESTE   (Italy)

Author keywords

Co seismic processes; Deformation; Precursors; Strainmeters; Tiltmeters

Indexed keywords

DEFORMATION; SEISMICITY; STRAIN MEASUREMENT; TILT;

EID: 0033399129     PISSN: 00128252     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0012-8252(99)00028-8     Document Type: Article

References (144)

1. Agnew D.C. Strainmeters and tiltmeters. Rev. Geophys. 24:1986;579-624.
2. Bawden G.W., Donnellan A., Kellogg L.H., Dong D., Rundle J.B. Geodetic measurements of horizontal strain near the White Wolf fault, Kern County, CA 1926-1993. J. Geophys. Res. 102:1997;4957-4967.
3. Beaumont C., Berger J. Earthquake prediction: modification of the earth tide tilts and strains by dilatancy. Geophys. J. R. Astron. Soc. 39:1974;111-121.
4. Bella F., Biagi P.F., Caputo M., Della Monica G., Ermini A., Manjgaladze P.V., Sgrigna V., Zilpimiani D.O. Possibile creep-related tilt precursors obtained in the Central Apennines (Italy) and in the Southern Caucasus (GA). Pure Appl. Geophys. 144:1995;277-300.
5. Benioff H. A linear strain seismograph. Bull. Seismol. Soc. Am. 25:1935;283-309.
6. Berger J., Lovberg R. Earth strain measurements with a laser interferometer. Science. 170:1970;296-303.
7. Berger J. A note on thermoelastic strains and tilts. J. Geophys. Res. 80:1976;274-277.
8. Biagi P.F., Caloi P., Migani M., Spadea M.C. Le variazioni d'inclinazione e la sismicità che hanno preceduto il forte terremoto del Friuli del 6 maggio 1976. Annali Geofis. 29:1976;137-146.
9. Bilham, R., 1981. Delays in the onset times of near-surface strain and tilt precursors to earthquakes. In: Simpson D.W., Richards, P.G. (Eds.), Earthquake Prediction, An International Review. AGU, Washington, pp. 411-421.
10. Biot M.A. General theory of three-dimensional consolidation. J. Appl. Phys. 12:1941;155-164.
11. Bolt B.A., Marussi A. Eigenvibrations of the earth observed at Trieste. Geophys. J. R. Astron. Soc. 6:1962;299-311.
12. Bonafede M., Boschi E., Dragoni M. Viscoelastic stress relaxation on deep fault sections as a possible source of very long period elastic waves. J. Geophys. Res. 88:1983;2251-2260.
13. Braitenberg C. Estimating the hydrologic induced signal in geodetic measurements with predictive filtering methods. Geophys. Res. Lett. 26:1999;775-778.
14. Braitenberg, C., Zadro, M., Bardelli, M., Mao, W.J., 1993. Variations of tidal responses in a seismic region: the Friuli-NE Italy case. In: Hsu, H.T. (Ed.), Proc. of the Twelfth International Symposium on Earth Tides, August 4-7, 1993, Beijing, pp. 395-401.
15. Braitenberg, C., Zadro, M., 1994. Strains, seismicity and rain. Proc. XXIV EUC General Assembly, September 19-24, Athens, Greece, Univ. Athens, Dept. Geophysics and Geothermy, pp. 1216-1224.
16. Brimich, L., 1992. Air pressure and temperature influence on the extensometric measurements at the Vyhne tidal station. In: Montag, H., Reigber, C. (Eds.), Proceedings of 7th International Symposium 'Geodesy and Physics of the Earth', Potsdam, October 5-10, 1992, Springer, pp. 190-193.
17. Bullen, K.E., Bolt, B.A., 1985. An Introduction to the Theory of Seismology. Cambridge Univ. Press, Cambridge.
18. Chapman, S., Lindzen, R.S., 1970. Atmospheric Tides. D. Reidel Publishing, Dordrecht-Holland, 200 pp.
19. Dal Moro, G., 1997. Deformazioni crostali nell'area sismica friulana: osservazioni e modelli. Doctoral Thesis, Trieste University, 192 pp.
20. Dal Moro G., Zadro M. Subsurface deformations induced by rainfall and atmospheric pressure: tilt/strain measurements in the NE-Italy seismic area. Earth Planet. Sci. Lett. 164:1998;193-303.
21. Dal Moro, G., Zadro, M., 1999. Remarkable tilt-strain anomalies preceding two seismic events in Friuli (NE Italy): their interpretation as precursors. Earth Planet. Sci. Lett., in press.
22. Delorme, H., Blum, P.-A., 1991. Tiltmeter network observations at Piton de la Fournaise Volcano (Reunion Island), 1985-1990. In: van Ruymbeke, M., d'Oreye, N. (Eds.), Proceedings of the Workshop: Geodynamical Instrumentation Applied to Volcanic Areas, Walferdange, 1-3 October, 1990. Centre Europeen de Geodynamique et de Seismologie, Luxembourg, pp. 99-109.
23. Dobrovolsky I.P., Zubkov S.I., Miachkin V.I. Estimation of the size of earthquake preparation zones. Pure Appl. Geophys. 117:1979;1025-1044.
24. Dragoni, M., Bonafede, M., Boschi, E., 1984-1985. On the interpretation of slow ground deformation precursory to the 1976 Friuli earthquake. Pure Appl. Geophys. 122, 781-792.
25. Du Y., Segall P., Gao H. Dislocations in inhomogeneous media via a moduli perturbation approach: general formulation and two-dimensional solutions. J. Geophys. Res. 99:1994;13767-13779.
26. Dubrov M.N., Alyoshin V.A. Laser starinmeters: new developments and earthquake prediction applications. Tectonophysics. 202:1992;209-213.
27. Eaton J.P. A portable water-tube tiltmeter. Bull. Seismol. Soc. Am. 49:1959;301-306.
28. Ebblin C. First estimates of the principal directions of strains compared to those of stresses in seismic Friuli, NE, Italy. Pure Appl. Geophys. 124:1986;897-917.
29. Ebblin, C., Zadro, M., 1979. On strain and tilt measurements in seismic areas. Proc. ESA-Council of Europe Seminar on Earthquake Prediction Strasbourg 5-7 March, 1979 ESA SP 149, 33-39.
30. Edge R.J., Baker T.F., Jeffries G. Borehole tilt measurements: aperiodic crustal tilt in an aseismic area. Tectonophysics. 71:1981;97-109.
31. Emter, D., Zürn, W., 1985. Observations of local elastic effects on earth tide strains. In: Harrison, J.C. (Ed.), Earth Tides. Van Nostrand-Reinhold, New York, 309-327.
32. Evans K., Wyatt F. Water table effects on the measurement of earth strain. Tectonophysics. 108:1984;323-337.
33. Flach, D., 1976. Present state of the development of the Askania borehole tiltmeter. In: Szadeczky-Kardoss, G. (Ed.), Proceedings of the Seventh Int. Symp. on Earth Tides. E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, pp. 249-258.
34. Furuya I., Fukudome A. Characteristics of borehole volume strainmeter and its application to seismology. J. Phys. Earth. 34:1986;257-296.
35. Gerstenecker, C., 1986. The investigation of air pressure and temperature effects on the Hughes Borehole tiltmeter by finite element analysis. In: Vieira, R. (Ed.), Proceedings of the Tenth International Symposium on Earth Tides. Madrid, pp. 923-932.
36. Gladwin M.T., Hart R. Design parameters for borehole strain instrumentation. Pure Appl. Geophys. 123:1985;59-77.
37. Gladwin M.T., Gwyther R.L., Hart R., Francis M., Johnston M.J.S. Borehole tensor strain measurements in California. J. Geophys. Res. 92:1987;7981-7988.
38. Gladwin M.T., Gwyther R.L., Higbie J.W., Hart R.G. A medium term precursor to the Loma Prieta earthquake? Geophys. Res. Lett. 18:1991;1377-1380.
39. Goulty N.R., King C.P., Wallard A.J. Iodine stilized laser strainmeter. Geophys. J. R. Astronom. Soc. 9:1974;269-282.
40. Groten, E., 1980. Geodesy and the Earth's Gravity Field, Vol. II: Geodynamics and Advanced Methods. Dümmler Verlag, Bonn, pp. 411-724.
41. Hagiwara T. Observations of changes in the inclination of the earth's surface at Mt. Tsukuba. Bull. Earthq. Res. Inst., Univ. Tokyo. 25:1947;27-32.
42. Harrison J.C. Cavity and topographic affects in tilt and strain measurement. J. Geophys. Res. 81:1976;319-328.
43. Hart R.H.G., Gladwin M.T., Gwyther R.L., Agnew D.C., Wyatt F.K. Tidal calibration of borehole strain meters: removing the effects of small-scale inhomogeneity. J. Geophys. Res. 101:1996;25553-25571.
44. Hast N. Global measurements of absolute stress. Philos. Trans. R. Soc. London A. 274:1973;409-419.
45. Horsfall J.A.C., King G.C.P. A new geophysical tiltmeter. Nature. 274:1977;675-676.
46. Haykin, S., 1983. Nonlinear methods in spectral analysis. Springer, Berlin, 263 pp.
47. Hudson J.A., Knopoff L. Predicting the overall properties of composite materials with small-scale inclusions or cracks. Pure Appl. Geophys. 131:1989;551-576.
48. Jaeger, J.C., 1983. Elasticity, Fracture and flow, Science paperbacks. Chapman & Hall, London, 268 pp.
49. L 3.2) near San Juan Bautista, CA. J. Geophys. Res. 91(B11):1986;11497-11502.
50. Johnston M.J.S., Linde A.T., Gladwin M.T., Borcherdt R.D. Fault failure with moderate earthquakes. Tectonophysics. 144:1987;189-206.
51. Johnston M.J.S., Linde A.T., Gladwin M.T. Near-field high resolution strain measurements prior to the October 18, 1989, Loma prieta Ms 7.1 earthquake. Geophys. Res. Lett. 17:1990;1777-1780.
52. Johnston M.J.S., Linde A.T., Agnew D.C. Continuous borehole strain in the San Andreas Fault zone before, during, and after the 28 June 1992, Mw 7.3 Landers, California. Earthquake, Bull. Seismol. Soc. Am. 84:1994;799-805.
53. Kanamori H. Re-examination of the earth's free oscillations excited by the Kamchatka earthquake of November 4, 1952. Phys. Earth Planet. Inter. 11:1976;216-226.
54. Kasahara K. Migration of crustal deformation. Tectonophysics. 52:1979;329-341.
55. Kasahara M., Shichi R., Okada Y. On the cause of long-period crustal movement. Tectonophysics. 97:1983;327-336.
56. Kawasaki I., Asai Y., Tamura Y., Sagiya T., Mikami N., Okada Y., Sakata M., Kasahara M. The 1992 Sanriku-Oki, Japan, ultra-slow earthquake. J. Phys. Earth. 43:1995;105-116.
57. King G.C.P., Bilham R. A geophysical wire strainmeter. Bull. Seismol. Soc. Am. 66:1976;2039-2047.
58. King C.-Y., Koizumi N., Kitagawa Y. Hydrogeochemical anomalies and the 1995 Kobe earthquake. Science. 269:1995;38-39.
59. Kirsch R., Zschau J. The influence of a dilatant region in the earth's crust on the earth tid tilt and strain. J. Geophys. 59:1986;157-163.
60. Kohl M.L., Levine J. Measurements and interpretation of tidal tilts in a small array. J. Geophys. Res. 100:1995;3929-3941.
61. Kümpel, H.J., 1986. Model calculations for rainfall induced tilt and strain anomalies. In: Vieira, R. (Ed.), Proceedings of the Tenth International Symposium on Earth Tides. Madrid, pp. 889-901.
62. Kümpel, H.J., 1989. Verformungen in der Umgebung von Brunnen. Habil. Thesis, Univ. of Kiel, Faculty of Mathematics and Natural Sciences, 198 pp.
63. Kümpel H.J., Peters J.A., Bower D.R. Nontidal tilt and water table variations in a seismically active region in Quebec, Canada. Tectonophysics. 152:1988;253-265.
64. Langbein J.O., Burford R.O., Slater L.E. Variations in fault slip and strain accumulation at Parkfield, California: initial result using two-color geodimeter measurements, 1984-1988. J. Geophys. Res. 95(B3):1990;2533-2552.
65. Larsen S., Reilinger R. Global positioning system measurements of strain accumulation across the Imperial Valley, California: 1986-1989. J. Geophys. Res. 97:1992;8865-8876.
66. Latynina L.A., Rizaeva S.D. On tidal-strain variations before earthquakes. Tectonophysics. 31:1976;121-127.
67. Latynina L.A., Abashizde V.G., Alexandrov, Kapanadze A.A., Karmaleeva P.M. Deformation observations in epicentral areas. Fizika Zemli. 3:1993;78-84. in Russian.
68. Levine J., Hall J.L. Design and operation of a methane absorption stabilized laser strainmeter. J. Geophys. Res. 77:1972;2595-2609.
69. Levine J., Meertens C., Busby R. Tilt observations using borehole tiltmeters: 1. Analysis of tidal and secular tilt. J. Geophys. Res. 94(B1):1989;574-586.
70. Linde A.T., Johnston M.J.S. Source parameters of the October 1, 1987 Whittier Narrows earthquake f crustal deformation data. J. Geophys. Res. 94(B7):1987;9633-9643.
71. Linde A.T., Gladwin M.T., Johnston M.J.S. The Loma Prieta earthquake, 1989 and earth strain tidal amplitudes: an unsuccessful search for associated changes. Geophys. Res. Lett. 19:1992;317-320.
72. Lorenzetti E., Tullis T.E. Geodetic predictions of a strike-slip fault model: Implications for intermediate- and short-term earthquake prediction. J. Geophys. Res. 94:1989;12343-12361.
73. Malvern, L.E., 1969. Introduction to the Mechanics of a Continuous Medium. Prentice-Hall, Englewood Cliffs, NJ, 713 pp.
74. Mao W.J., Ebblin C., Zadro M. Evidence for variations of mechanical properties in the Friuli seismic area. Tectonophysics. 170:1989;231-242.
75. Mao W.J., Santero P., Zadro M. Long- and middle-term behaviour of the tilt and strain variations in the decade following the 1976 Friuli earthquake in NE Italy. Pure Appl. Geophys. 132:1990;653-677.
76. Marussi, A., 1960. The University of Trieste station for the study of the tides of the vertical in the Grotta Gigante. Proceedings of the III Int. Symposium on Earth Tides, Trieste, pp. 45-52.
77. Matsu'ura M., Tanimoto T. Quasi-static deformations due to an inclined, rectangular fault in a viscoelastic half-space. J. Phys. Earth. 28:1980;103-118.
78. Meertens C., Levine J., Busby R. Tilt observations using borehole tiltmeters: 2. Analysis of data from Yellowstone National Park. J. Geophys. Res. 94:1989;587-601.
79. McHugh S., Johnston M.J.S. Short-period nonseismic tilt perturbations and their relation to episodic slip on the San Andreas fault in Central California. J. Geophys. Res. 81:1976;6341-6346.
80. McTigue D.F., Segall P. Displacements and tilts from dip-slip faults and magma chambers beneath irregular surface topography. Geophys. Res. Lett. 15:1988;601-604.
81. Melchior, P., 1983. The Tides of the Planet Earth. Pergamon, Oxford, 641 pp.
82. Melchior P., Ducarme B. The ratio l/h: A simple method for the prospection of tidal deformations of cavities in the Earth's crust. Bull. Geod. 50:1976;137-138.
83. Michelson A.A. Preliminary results of measurements of the rigidity of the earth. Astrophys. J. 39:1914;105-134.
84. Mjachkin V.I., Brace W.F., Sobolev G.A., Dieterich J.H. Two models for earthquake forerunners. Pure Appl. Geophys. 113:1975;169-181.
85. Mogi K. Sequential occurrence of recent great earthquakes. J. Phys. Earth. 16:1968;30-36.
86. Mogi, K., 1981. Earthquake Prediction program in Japan. In: Simpson, D.W., Richards, P.G. (Eds.), Earthquake prediction, An international Review. AGU, Washington, 635-666.
87. Mueller R., Johnston M.J.S., Myren G.D. Lake level observations to detect crustal tilt: the San Andreas Lake, California, 1979-1989. Geophys. Res. Lett. 16:1989;661-664.
88. Nersesov I.L., Latynina L.A. Strain processes before Spitak earthquake. Tectonophysics. 202:1992;221-225.
89. O'Connell R.J., Budiansky B. Seismic velocities in dry and saturated cracked solids. J. Geophys. Res. 79:1974;5412-5426.
90. Ohya F. Crustal movements related to the earthquake on March 18, 1987 in Hyuganada. Bull. Disas. Prev. Res. Inst., Kyoto Univ. 38:1988;99-114.
91. Okada Y. Surface deformation due to shear and tensile faults in a half-space. Bull. Seismol. Soc. Am. 75:1985;1135-1154.
92. Ostrovsky Le clinomètre à enregistrement photo-électrique. B.I.M. 25:1961;500-536.
93. Pagiatakis, S.D., Vaníček, P., 1986. Atmospheric perturbations of tidal tilt and gravity measurements at the U.N.B. earth tides station. In: Vieira, R. (Ed.), Proceedings of the Tenth International Symposium on Earth Tides. Madrid, pp. 905-922.
94. Pearson C.F., Beavan J., Darby D.J., Blick G.H., Walcott R.I. Strain distribution across the Australian-Pacific plate boundary in the central South Island, New Zealand, from 1992 GPS and earlier terrestrial observations. J. Geophys. Res. 100:1995;22071-22081.
95. Peters, J., Beaumont, C., 1981. Preliminary results from a new borehole tiltmeter at Charlevoix, Québec. Proceedings of the Ninth International Symposium on Earth Tides. New York City, pp. 69-77.
96. Prescott W.H., Savage J.C., Kinoshita W.T. Strain accumulation rates in the western United States between 1970 and 1978. J. Geophys. Res. 84:1979;5423-5435.
97. Rabbel W., Zschau J. Static deformations and gravity changes at the earth's surface due to atmospheric loading. J. Geophys. 56:1985;1-99.
98. Rikitake, T., 1976. Earthquake Prediction. Elsevier, Amsterdam, 357 pp.
99. Rodgers P.W. The response of the horizontal pendulum seismometer to Rayleigh and Love waves, tilt, and free oscillations of the earth. Bull. Seismol. Soc. Am. 58:1968;1384-1406.
100. Roeloffs E., Quilty E. Water level and strain changes preceeding and following the August 4, 1985 Kettleman Hills, California, earthquake. Pure Appl. Geophys. 149:1997;21-60.
101. Rojstaczer S. Intermediate period response of water levels in wells to crustal strain: sensitivity and noise level. J. Geophys. Res. 93:1988;13619-13630.
102. Rossi G., Zadro M. Long-term crustal deformations in NE Italy revealed by tilt-strain gauges. Phys. Earth Planet. Int. 97:1996;55-70.
103. van Ruymbeke, M., d'Oreye, N., 1991. Design and construction of instruments adapted to volcanic zones. In: van Ruymbeke, M., d'Oreye, N. (Eds.), Proceedings of the Workshop: Geodynamical Instrumentation Applied to Volcanic Areas, Walferdange, 1-3 October, 1990. Centre Europeen de Geodynamique et de Seismologie, Luxembourg, pp. 57-70.
104. Sacks I.S., Evertson D.W. A sensitive borehole strain-rate meter. Carnegie Inst. Washington Yearbook. 68:1968;448-455.
105. Sato K. Numerical experiments on strain migration. J. Geod. Soc. Jpn. 35:1989;27-36.
106. Sato T., Harrison J.C. Local effects on tidal strain measurements at Esashi, Japan. Geophys. J. Int. 102:1990;513-526.
107. Savage J.C., Lisowski M. Strain accumulation in Owens Valley, California, 1974 to 1988. Bull. Seismol. Soc. Am. 85:1995;151-158.
108. Savage J.C., Lisowski M., Svarc J.L., Gross W.K. Strain accumulation across the central Nevada seismic zone, 1973-1994. J. Geophys. Res. 100:1995;20257-20269.
109. Schmitz-Hübsch, H., 1986. Use of a 30 m vertical tiltmeter for the detection of the actual crustal movement. In: Vieira, R. (Ed.), Proc. Tenth Int. Symp. on Earth tides, Consejs Sup. de Invets. Cientif., Madrid, pp. 855-864.
110. Scholz, C.H., 1990. The Mechanics of Earthquake Faulting. Cambridge Univ. Press, Cambridge, 439 pp.
111. Scholz C.H., Sykes L.R., Aggarwal Y.P. Earthquake prediction: a physical basis. Science. 181:1973;803-809.
112. Simon D., Schneider M.M. Zum Auftreten luftdruckbedingter Storungen in Horizontalpendelaufzeichnungen auf drei verschiedenen Erdgezeitenstationen. B.I.M. 49:1967;2218-2225.
113. Stuart W.D., Tullis T.E. Fault model for preseismic deformation at Parkfield, California. J. Geophys. Res. 100(B12):1995;24079-24099.
114. Takemoto S. Laser interferometer systems for precise measurements of ground-strains. Bull. Disaster Prev. Res. Inst. Kyoto Univ. 29:1979;65-81.
115. Takemoto S. Application of laser holographic tecniques to investigate crustal deformations. Nature. 322:1986;49-51.
116. Takemoto S. Laser holographic measurements of tidal deformation of a tunnel. Geophys. J. Int. 100:1990;99-106.
117. Takemoto S. Some problems on detection of earthquake precursors by means of continuous monitoring of crustal strains and tilts. J. Geophys. Res. 96:1991;10377-10390.
118. Takemoto S. Recent results obtained from continuous monitoring of crustal deformation. J. Phys. Earth. 43:1995;407-420.
119. Tanaka, T., Shimojima, E., Mitamura, K., Hoso, Y., Ishihara, Y., 1989. Precipitation, groundwater and ground deformation. In: Vyskocil, P., Reigber, C., Cross, P.A. (Eds.), Global and regional geodynamics, Edinburgh, Scotland, August 3-5, 1989, Springer, Berlin, pp. 132-139.
120. Tomaschek R. Non-elastic tilt of the earth's crust due to meteorological pressure distributions. Geof. Pura e Applicata. 25:1953;17-25.
121. Tse S.T., Rice J.R. Crustal earthquake instability in relation to the depth variation of frictional slip properties. J. Geophys. Res. 91:1986;9452-9472.
122. Tsunogai U., Wakita H. Precursory chemical changes in ground water: Kobe earthquake, Japan. Science. 269:1995;61-63.
123. Varga P. Long-term variations recorded by extensometers. J. Geophys. 55:1984;68-70.
124. Varga P., Varga T. Horizontal deformations recorded with the extensometers. B.I.M. 122:1995;9272-9276.
125. Verbaandert J. L'étalonnage des pendules horizontaux. Boll. Geofis. Teor. Appl. 4:1962;419-446.
126. Verbaandert J., Melchior P. Les stations geophysiques souterraines et les pendules horizontaux de l'Observatoire Royal de Belgique. Monogr. Obs. R. Belg. 7:1961;1-147.
127. Vieira, R., van Ruymbeke, M., Fernandez, J., Arnoso, J., Toro, C., 1991. The Lanzarore Underground laboratory. In: van Ruymbeke, M., d'Oreye, N. (Eds.), Proceedings of the workshop: Geodynamical instrumentation applied to volcanic areas, Walferdange, 1-3 October, 1990. Centre Europeen de Geodynamique et de Seismologie, Luxembourg, pp. 71-86.
128. Weise, A., Jentzsch, G., Kääriäinen, J., Kiviniemi, A., Ruotsalainen, H., 1995. Tilt measurements in geodynamics-results from the 3-component-station Metsähovi and the clinometric station Lohja-Finland. In: Hsu, H.T. (Ed.), Proceedings of the Twelth Int. Symp. on Earth Tides, Beijing, August 4-7, 1993, pp. 105-114.
129. Weise A., Jentzsch G., Kiviniemi A., Kääriäinen J. Comparison of long-period tilt measurements: results from the two clinometric stations Metsähovi and Lohja, Finland. J. Geodynamics. 27:1999;237-257.
130. Westerhaus, M., 1997. Tidal tilt modification along an active fault. In: Wilhelm, H., Zürn, W., Wenzel, H.-G. (Eds.), Tidal Phenomena, Lecture Notes in Earth Sciences 66. Springer, Heidelberg, pp. 311-339.
131. Wolfe J.E., Berg E., Sutton G.H. The change in strain comes mainly from the rain: Kipapa, Oahu. Bull. Seismol. Soc. Am. 71:1981;1625-1635.
132. Wood M.D., Allen R.V. Anomalous microtilt preceding a local earthquake. Bull. Seismol. Soc. Am. 61:1971;1801-1809.
133. Wood M.D., King N.E. Relation between earthquakes, weather, and soil tilt. Science. 197:1977;154-156.
134. Wyatt F.K. Measurements of coseismic deformation in Southern California: 1972-1982. J. Geophys. Res. 93:1988;7923-7942.
135. Wyatt F.K., Agnew D.C., Gladwin M. Continuous measurements of crustal deformation for the 1992 Landers earthquake sequence. Bull. Seismol. Soc. Am. 84:1994;768-779.
136. Wyatt F.K., Morrissey S.-T., Agnew D.C. Shallow borehole tilt: a reprise. J. Geophys. Res. 93:1988;9127-9201.
137. Yamauchi T. Anomalous strain response to rainfall in relation to earthquake occurrence in the Tokai area, Japan. J. Phys. Earth. 35:1987;19-36.
138. Yamauchi T. Earthquake occurrence and temporal variations in Earth tidal amplitudes. J. Geod. Soc. Jpn. 35:1989;149-157.
139. Zadro M. Use of tiltmeters for the detection of forerunning events in seismic areas. Boll. Geod. Sc. Aff. 2 to 3:1978;597-618.
140. Zadro M., Plenizio E., Ebblin C., Chiaruttini C. Influence of groundwater table level variations and of rainfall on tilting in the Friuli area, NE, Italy. Acta Geophysica Polonica. 35:1987;323-338.
141. Zadro M., 1992. Tilt and strain variations in Friuli, NE Italy, after the 1976 Eartquake. In: Boschi, E., Dragoni, M. (Eds.), Earthquake Prediction (International School on Earthquake Prediction, Erice, Italy, July 1989), Il Cigno Galileo Galilei, Roma, pp. 295-315.
142. Zschau, J., 1977. Air pressure induced tilt in porous media. Proc. 8th Int. Symp. on Earth Tides, Bonn, pp. 418-433.
143. Zürn W. Local observation and interpretation of geodynamic phenomena. Acta Geod. Geophys. Hung. 29:1994;339-362.
144. Zürn, W., Emter, D., Heil, E., Neuberg, J., Grüninger, W., 1986. Comparison of short and long baseline tidal tilts. In: Vieira, R. (Ed.), Proc. 10th Int. Symp. Earth Tides, Cons. Sup. Inv. Cient., Madrid, pp. 61-69.