none 10.1190/1.1442776 Society of Exploration Geophysicists Society of Exploration Geophysicists 186 4729584 5981 2025121110275724200 10.1190 2025-12-11T15:28:03Z 2002-10-11T15:09:34Z 69 Geophysics 1942-2156 0016-8033 01 01 1990 01 01 1990 55 1 Mark Sams Imp. Coll., Dep. Geol., London, United Kingdom David Goldberg Lamont-Doherty Geol. Obs., United States Abstract The measurement from borehole sonic data of Q, the acoustic attenuation coefficient of an earth section, can be achieved in three ways: forward modeling (Chuen and Toksoez, 1981), spectral ratios (Gladwin and Stacey, 1974), and inversion (Cheng et al., 1986). The spectral-ratio technique has been applied to real data (Goldberg et al., 1985) but is unstable and not very reliable. Experiments have shown that the spectral-ratio technique applied to waveforms gives Q estimates which are lower than those measured from cores in the laboratory (Goldberg and Zinszner, 1989). We investigate this phenomenon using synthetic and real data. 01 01 1990 01 01 1990 01 01 1990 97 101 10.1190/1.1442776 https://pubs.geoscienceworld.org/geophysics/article/55/1/97/72318/The-validity-of-Q-estimates-from-borehole-data https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/55/1/97/3160301/97.pdf https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/55/1/97/3160301/97.pdf http://geophysics.geoscienceworld.org/cgi/doi/10.1190/1.1442776