{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T11:57:37Z","timestamp":1781697457537,"version":"3.54.5"},"reference-count":32,"publisher":"American Association for the Advancement of Science (AAAS)","issue":"5463","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Science"],"published-print":{"date-parts":[[2000,4,7]]},"abstract":"<jats:p>Regional distance seismic moment tensor determinations and broadband waveforms of moment magnitude 4.6 to 4.9 earthquakes from a November 1997 Long Valley Caldera swarm, during an inflation episode, display evidence of anomalous seismic radiation characterized by non\u2013double couple (NDC) moment tensors with significant volumetric components. Observed coseismic dilation suggests that hydrothermal or magmatic processes are directly triggering some of the seismicity in the region. Similarity in the NDC solutions implies a common source process, and the anomalous events may have been triggered by net fault-normal stress reduction due to high-pressure fluid injection or pressurization of fluid-saturated faults due to magmatic heating.<\/jats:p>","DOI":"10.1126\/science.288.5463.122","type":"journal-article","created":{"date-parts":[[2002,7,27]],"date-time":"2002-07-27T09:48:21Z","timestamp":1027763301000},"page":"122-125","source":"Crossref","is-referenced-by-count":163,"title":["Dilational Processes Accompanying Earthquakes in the Long Valley Caldera"],"prefix":"10.1126","volume":"288","author":[{"given":"Douglas S.","family":"Dreger","sequence":"first","affiliation":[{"name":"Berkeley Seismological Laboratory, University of California, Berkeley, CA 94720, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hrvoje","family":"Tkalc\u030cic\u0301","sequence":"additional","affiliation":[{"name":"Berkeley Seismological Laboratory, University of California, Berkeley, CA 94720, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malcolm","family":"Johnston","sequence":"additional","affiliation":[{"name":"U.S. Geological Survey, Menlo Park, CA 94025, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"221","reference":[{"key":"e_1_3_1_2_2","doi-asserted-by":"crossref","first-page":"11111","DOI":"10.1029\/JB090iB13p11111","volume":"90","author":"Hill D. P.","year":"1985","unstructured":"Hill D. P., Bailey R. A., Ryall A. S., J. Geophys. Res. 90, 11111 (1985).","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_3_2","doi-asserted-by":"crossref","first-page":"1093","DOI":"10.1785\/BSSA0720041093","volume":"72","author":"Given J. W.","year":"1982","unstructured":"Given J. W., Wallace T. C., Kanamori H., Bull. Seismol. Soc. Am. 72, 1093 (1982);","journal-title":"Bull. Seismol. Soc. Am."},{"key":"e_1_3_1_3_3","first-page":"769","volume":"64","author":"Ekstrom G.","year":"1983","unstructured":"Ekstrom G., Eos 64, 769 (1983);","journal-title":"Eos"},{"key":"e_1_3_1_3_4","first-page":"262","volume":"64","author":"Ekstrom G.","year":"1983","unstructured":"Ekstrom G., Dziewonski A. M., Eos 64, 262 (1983);","journal-title":"Eos"},{"key":"e_1_3_1_3_5","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1038\/303323a0","volume":"303","author":"Julian B. R.","year":"1983","unstructured":"Julian B. R., Nature 303, 323 (1983);","journal-title":"Nature"},{"key":"e_1_3_1_3_6","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1785\/BSSA0730020419","volume":"73","author":"Barker J. S.","year":"1983","unstructured":"Barker J. S., Langston C. A., Bull. Seismol. Soc. Am. 73, 419 (1983);","journal-title":"Bull. Seismol. Soc. Am."},{"key":"e_1_3_1_3_7","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1029\/GL009i010p01131","volume":"9","author":"Wallace T.","year":"1982","unstructured":"Wallace T., Given J., Kanamori H., Geophys. Res. Lett. 9, 1131 (1982).","journal-title":"Geophys. Res. Lett."},{"key":"e_1_3_1_4_2","first-page":"E963","volume":"79","author":"Langbein J.","year":"1998","unstructured":"Langbein J., Wilkinson S., Feinberg J., Johnston M., Eos 79, E963 (1998);","journal-title":"Eos"},{"key":"e_1_3_1_4_3","first-page":"E949","volume":"79","author":"Hill D. P.","year":"1998","unstructured":"Hill D. P., Eos 79, E949 (1998).","journal-title":"Eos"},{"key":"e_1_3_1_5_2","unstructured":"The method used inverts complete three-component long-period (50 to 20 s) displacement seismograms for the six independent elements of the symmetric seismic moment tensor. A synchronous and impulsive source time function and spatial point-source are assumed. A linear inversion for moment tensor amplitudes is then possible. The event source depth is determined iteratively by performing independent inversions for depths of 5 8 11 14 and 17 km. See for example"},{"key":"e_1_3_1_5_3","doi-asserted-by":"crossref","first-page":"8107","DOI":"10.1029\/93JB00023","volume":"98","author":"Dreger D. S.","year":"1993","unstructured":"Dreger D. S., Helmberger D. V., J. Geophys. Res. 98, 8107 (1993);","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_5_4","doi-asserted-by":"crossref","first-page":"1255","DOI":"10.1785\/BSSA0860051255","volume":"86","author":"Pasyanos M. E.","year":"1996","unstructured":"Pasyanos M. E., Dreger D. S., Romanowicz B., Bull. Seismol. Soc. Am. 86, 1255 (1996) .","journal-title":"Bull. Seismol. Soc. Am."},{"key":"e_1_3_1_6_2","doi-asserted-by":"crossref","first-page":"4957","DOI":"10.1029\/JB075i026p04957","volume":"75","author":"Knopoff L.","year":"1970","unstructured":"Knopoff L., Randall M. J., J. Geophys. Res. 75, 4957 (1970);","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_6_3","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1785\/gssrl.60.2.37","volume":"60","author":"Jost M. L.","year":"1989","unstructured":"Jost M. L., Hermann R. B., Seismol. Res. Lett. 60, 37 (1989).","journal-title":"Seismol. Res. Lett."},{"key":"e_1_3_1_7_2","unstructured":"The percent CLVD is calculated from the minimum and maximum eigenvalues defined by (\u2016\u03bb 3 \u2016 > \u2016\u03bb 2 \u2016 > \u2016\u03bb 1 \u2016) where \u03b5 = \u2016\u03bb 1 \/\u03bb 3 \u2016 and PCLVD = 200\u03b5 and PDC = 100 \u2212 200\u03b5. The percent isotropic (ISO) is the ratio of the isotropic moment to the sum of the isotropic and deviatoric moments."},{"key":"e_1_3_1_8_2","doi-asserted-by":"crossref","first-page":"11171","DOI":"10.1029\/JB090iB13p11171","volume":"90","author":"Wallace T. C.","year":"1985","unstructured":"Wallace T. C., J. Geophys. Res. 90, 11171 (1985).","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_9_2","doi-asserted-by":"crossref","first-page":"15457","DOI":"10.1029\/94JB00140","volume":"99","author":"Kuge K.","year":"1994","unstructured":"Kuge K., Lay T., J. Geophys. Res. 99, 15457 (1994).","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_10_2","doi-asserted-by":"crossref","first-page":"804","DOI":"10.1126\/science.264.5160.804","volume":"264","author":"Frohlich C.","year":"1994","unstructured":"Frohlich C., Science 264, 804 (1994).","journal-title":"Science"},{"key":"e_1_3_1_11_2","doi-asserted-by":"crossref","first-page":"11155","DOI":"10.1029\/JB090iB13p11155","volume":"90","author":"Julian B. R.","year":"1985","unstructured":"Julian B. R., Sipkin S. A., J. Geophys. Res. 90, 11155 (1985).","journal-title":"J. Geophys. Res."},{"key":"e_1_3_1_12_2","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1111\/j.1365-246X.1996.tb05308.x","volume":"126","author":"Kawakatsu H.","year":"1996","unstructured":"Kawakatsu H., Geophys. J. Int. 126, 525 (1996);","journal-title":"Geophys. J. 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F., Sileny J., Tectonophysics 261, 147 (1996);","journal-title":"Tectonophysics"},{"key":"e_1_3_1_13_4","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1111\/j.1365-246X.1996.tb04737.x","volume":"127","author":"Hara T.","year":"1996","unstructured":"Hara T., Kuge K., Kawakatsu H., Geophys. J. Int. 127, 515 (1996).","journal-title":"Geophys. J. Int."},{"key":"e_1_3_1_14_2","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1029\/98RG00717","volume":"36","author":"Miller A. D.","year":"1998","unstructured":"Miller A. D., Foulger G. R., Julian B. R., Rev. Geophys. 36, 551 (1998).","journal-title":"Rev. Geophys."},{"key":"e_1_3_1_15_2","unstructured":"U. S. Geological Survey Volcano Hazards Program Long Valley Caldera Monitoring Report 1997."},{"key":"e_1_3_1_16_2","unstructured":"It is possible to fit the data better with models that have a greater number of unknowns. The F test is used to determine whether a model with a change in the number of free parameters fits the data significantly better than might be expected from random fluctuations in the data [W. Menke Geophysical Data Analysis: Discrete Inverse Theory (Academic Press New York 1989) pp. 96\u201397. There are five unknowns in the DC inversions (depth scalar seismic moment strike rake and dip) six in the deviatoric moment tensor inversion and seven in the full moment tensor inversion. To perform the test the variance \u03c3 2 of the data is estimated from the model prediction error e i = (data i \u2212 synthetic i ) where \u03c3 2 = \u2211 e i 2 \/( N \u2212 M ) and N and M are the number of observations and model parameters respectively. The F statistic is the ratio of the two data variance estimates. Critical values of F above which the difference in the variance is significant can be calculated from the F distribution. For the calculations in this report considering a 20-s correlation length for the data the critical values of F are 1.36 (95% confidence) and 1.55 (99% confidence)."},{"key":"e_1_3_1_17_2","unstructured":"Given the definitions of scalar seismic moment M 0 = \u03bc AD and static stress drop \u0394\u03c3 = c \u03bc D \/ L where \u03bc is the material rigidity at the source A (equal to L 2 ) is the source area and D is the average slip L is the source dimension and c is a geometrical constant approximately equal to 1 the following relationship for L is found: L \u2248 ( M 0 \/\u0394\u03c3) 1\/3 . The source duration \u03c4 is then found to approximately equal ( M 0 \/\u0394\u03c3) 1\/3 \/\u03b2 where \u03b2 is the seismic shear-wave velocity."},{"key":"e_1_3_1_18_2","first-page":"1073","volume":"65","author":"Kanamori H.","year":"1975","unstructured":"Kanamori H., Anderson D., Bull. Seismol. Soc. Am. 65, 1073 (1975).","journal-title":"Bull. Seismol. Soc. Am."},{"key":"e_1_3_1_19_2","unstructured":"K. Aki and P. Richards Quantitative Seismology Theory and Methods (Freeman San Francisco 1980) p. 932."},{"key":"e_1_3_1_20_2","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/0040-1951(87)90017-5","volume":"144","author":"Johnston M. J. S.","year":"1987","unstructured":"Johnston M. J. S., Linde A. T., Gladwin M. T., Borcherdt R. D., Tectonophysics 144, 189 (1987).","journal-title":"Tectonophysics"},{"key":"e_1_3_1_21_2","unstructured":"This is contribution 00-02 of the Berkeley Seismological Laboratory."}],"container-title":["Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.science.org\/doi\/pdf\/10.1126\/science.288.5463.122","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,1,13]],"date-time":"2024-01-13T10:10:52Z","timestamp":1705140652000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.science.org\/doi\/10.1126\/science.288.5463.122"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2000,4,7]]},"references-count":32,"journal-issue":{"issue":"5463","published-print":{"date-parts":[[2000,4,7]]}},"alternative-id":["10.1126\/science.288.5463.122"],"URL":"https:\/\/doi.org\/10.1126\/science.288.5463.122","relation":{},"ISSN":["0036-8075","1095-9203"],"issn-type":[{"value":"0036-8075","type":"print"},{"value":"1095-9203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2000,4,7]]}}}