Abstract
Coda wave data from California microearthquakes were studied in order to delineate regional fluctuations of apparent crustal attenuation in the band 1.5 to 24 Hz. Apparent attenuation was estimated using a single back scattering model of coda waves. The coda wave data were restricted to ≤ 30 s following the origin time; this insures that crustal effects dominate the results as the backscattered shear waves thought to form the coda would not have had time to penetrate much deeper. Results indicate a strong variation in apparent crustal attenuation at high frequencies between the Franciscan and Salinian regions of central California and the Long Valley area of the Sierra Nevada. Although the coda Q measurements coincide at 1.5 Hz (Q c = 100), at 24 Hz there is a factor of four difference between the measurements made in Franciscan (Q c = 525) and Long Valley (Q c = 2100) with the Salinian midway between (Q c = 900). These are extremely large variations compared to measures of seismic velocities of comparable resolution, demonstrating the exceptional sensitivity of the high frequency coda Q measurement to regional geology. In addition, the frequency trend of the results is opposite to that seen in a compilation of coda Q measurements made worldwide by other authors which tend to converge at high and diverge at low frequencies, however, the worldwide results generally were obtained without limiting the coda lengths and probably reflect upper mantle rather than crustal properties. Our results match those expected due to scattering in random media represented by Von Karman autocorrelation functions of orders 1/2 to 1/3. The Von Karman medium of order 1/3 corresponding to the Franciscan coda Q measurement contains greater amounts of high wavenumber fluctuations. This indicates relatively large medium fluctuations with wavelengths on the order of 100 m in the highly deformed crust associated with the Franciscan, however, the influence of scattering on the coda Q measurement is currently a matter of controversy.
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References
Aki, K. (1980a), Attenuation of shear waves in the lithosphere for frequencies from 0.05 to 25 Hz, Phys. Earth Planet. Interiors 21, 50–60.
Aki, K. (1980b), Scattering and attenuation of shear waves in the lithosphere, J. Geophys. Res. 85, 6496–6504.
Aki, K. and Chouet, B. (1975), Origin of coda waves: Source, attenuation and scattering effects, J. Geophys. Res. 80, 3322–3342.
Chouet, B. (1979), Temporal variations in the attenuation of earthquake coda near Stone Canyon, California, Geophys. Res. Lett. 6, 143–146.
Chouet, B., Aki, K., and Tsujiura, M. (1978), Regional variation of the scaling law of earthquake source spectra, Bull. Seism. Soc. Am. 68, 59–79.
Eaton, J. P. (1977), Frequency response of the USGS short-period telemetered seismic system and its suitability for network studies of local earthquakes, USGS Open File Report 77–844.
Eaton, J. P. (1980), Response arrays and sensitivity coefficients for standard configurations of the USGS short period telemetered system, USGS Open File Report 80–316.
Ernst, W. G., Summary of the geotectonic development of California, in Geotectonic Development of California (W. G. Ernst, ed.) (Prentice-Hall, Englewood Cliffs, N.J. 1981) pp. 602–613.
Fehler, M. C., Fairbanks, T., and Roberts, P. M. (1987), Variation in coda Q before and after an eruption of Mount St. Helens, Hawaii Symposium on How Volcanoes Work, 71.
Frankel, A. and Clayton, R. W. (1984), A finite difference simulation of wave propagation in twodimensional random media, Bull. Seism. Soc. Am. 74, 2167–2186.
Frankel, A. and Clayton, R. W. (1986), Finite difference simulations of seismic scattering: Implications for the propagation of short period seismic waves in the crust and models of crustal heterogeneity, J. Geophys. Res. 91, 6465–6490.
Guzev, A. H. and Lemzikov, V. K. (1985), Properties of scattered elastic waves in the lithosphere of Kamchatka: Parameters and temporal variations, Tectonphys. 112, 137–153.
**, A., Cao, T., and Aki, K. (1985), Regional change of coda Q in the oceanic lithosphere, J. Geophys. Res. 90, 8651–8659.
**, A. and Aki, K. (1986), Temporal change in coda Q before the Tangshan earthquake of 1976 and the Haicheng earthquake of 1975, J. Geophys. Res. 91, 665–674.
Lee, W. H. K. and Stewart, S. W., Principles and Applications of Microearthquake Networks (Academic Press, New York 1981).
Lee, W. H. K., Aki, K., Chouet, B., Johnson, P., Marks, S., Newberry, J. T., Ryall, A. S., Stewart, S. W., and Tottingham, D. M. (1986), Preliminary study of coda Q in California and Nevada, Bull. Seism. Soc. Am. 76, 1143–1150.
Mooney, W. D. and Luetgart, J. H. (1982), A seismic refraction study of the Santa Clara Valley and southern Santa Cruz Mountains, west-central California, Bull. Seism. Soc. Am. 72, 901–909.
Peng, J. Y., Aki, K., Lee, W. H. K., Chouet, B., Johnson, P., Marks, S., Newberry, J. T., Ryall, A. S., Stewart, S., and Tottingham, D. M. (1987), Temporal change in coda Q associated with the Round Valley, California, earthquake of November 23, 1984, J. Geophys. Res. 92, 3507–3526.
Phillips, W. S. (1985), The separation of source, path and site effects on high frequency seismic waves: An analysis using coda wave techniques, Ph.D. thesis, M.I.T., Cambridge, MA.
Phillips, W. S. and Aki, K. (1986), Site amplification of coda waves from local earthquakes in central California, Bull. Seism. Soc. Am. 76, 627–648.
Pulli, J. J. (1984), Attenuation of coda waves in New England, Bull. Seism. Soc. Am. 74, 1149–1166.
Rautian, T. G. and Khalturin, V. I. (1978), The use of the coda for determination of the earthquake source spectrum, Bull. Seism. Soc. Am. 68, 923–948.
Reiter, L. and Monfort, M. E. (1977), Variations in initial pulse width as a function of anelastic properties and surface geology in central California, Bull. Seism. Soc. Am. 67, 1319–1338.
Roberts, P. M. (1985), A study of coda and S-wave attenuation at Mammoth Lakes, California, Abstract, EOS, 66, 984.
Roecker, S. W., Tucker, B., King, J., and Hatzfeld, D. (1982), Estimates of Q in Central Asia as a function of frequency and depth using the coda of locally recorded earthquakes, Bull. Seism. Soc. Am. 72, 129–149.
Sato, H. (1977), Energy propagation including scattering effects, single isotropic scattering approximation, J. Phys. Earth 25, 27–41.
Sato, H. (1982), Amplitude attenuation of impulsive waves in random media based on travel time corrected mean wave formalism, J. Acoust. Soc. Am. 71, 559–564.
Sato, H. (1987), A precursorlike change in coda excitation before the Western Nagano earthquake (M s = 6.8) of 1984 in central Japan, J. Geophys. Res. 92 1356–1360.
Singh, S. K. and Herrmann, R. B. (1983), Regionalization of crustal coda Q in the continental United States, J. Geophys. Res. 88, 527–538.
Stewart, S. W. and O’neill, M. E. (1980), Calculation of the frequency response of the USGS telemetered short-period seismic system, USGS Open File Report 80–143.
Tsujiura, M. (1978), Spectral analysis of the coda waves from local earthquakes, Bull. Earthquake Res. Inst., Univ. Tokyo 53, 1–48.
Walter, A. W. and Mooney, W. P. (1982), Crustal structure of the Diablo and Gabilan Ranges, central California: A reinterpretation of existing data, Bull. Seism. Soc. Am. 72, 1567–1590.
Wesson, R. L., Roller, J. C., and Lee, W. H. K. (1973), Time-term analysis and geological interpretation of seismic travel time data from the Coast Ranges of central California, Bull. Seism. Soc. Am. 63, 1447–1471.
Wilson, M., Wyss, M., and Koyanagi, R. (1983), Temporal attenuation changes in the Koae fault system, southern Hawaii, EOS, 64, 761.
Wu, R. S. (1982), Attenuation of short period seismic waves due to scattering, Geophys. Res. Lett. 9, 9–12.
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Phillips, W.S., Lee, W.H.K., Newberry, J.T. (1988). Spatial Variation of Crustal Coda Q in California. In: Aki, K., Wu, RS. (eds) Scattering and Attenuations of Seismic Waves, Part I. Pageoph Topical Volumes. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-7722-0_13
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DOI: https://doi.org/10.1007/978-3-0348-7722-0_13
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