Historical Seismograms - Evidence from the AD 2000 Izu Islands ...

The U. S. Geological Survey’s Databases of Seismic Events 149computer facility at the Stanford Linear Accelerator Center (SLAC). The designof this system is described in Lee et al. (1983), its implementation is presented inCrane et al. (1984), and a guide to its use is given in Crane et al. (1985). The SLACcomputer and the VAX-type computers are accessible via high-speed commercialdata transfer networks, which are linked to computers at major universities in theU.S. and abroad.5. ConclusionIn recent years many new parameters have been added to those already used todescribe earthquakes. Among the new parameters are moment tensor components,seismic moment, stress drop, average displacement, rupture length (and width),rupture area, fault plane and stress axes descriptors, M, magnitude, ML, magnitude,Md magnitude, magnitude statistics, and ground motion descriptors. Theglobal database format contains alphanumeric flags, which, when set, indicate theexistence of some of the above data. The primary format of the national databaseaccommodates many of these parameters, and binary flags point to secondary filesin the database that contain much of the remaining new data. Furthermore, thenational database can be expanded as necessary to acccommodate new event parametersthat may be routinely determined in the future.REFERENCESAbe, K. (1981). Magnitudes of large shallow earthquakes from 1904 to 1980, Phys. EarthPlanet. Interiors, 27, 72-92.Abe, K. and S. Noguchi (1983). Revision of magnitudes of large shallow earthquakes,1897-1912, Phys. Earth Planet. Interiors, 33, 1-11.Coffman, J. L., C. A. von Hake, and C. W. Stover (1982). Earthquake history of theUnited States, revised edition with supplement (through 1980): Washington, D.C,US. Government Printing Office, 208+50a p.Crane, G. R., W. H. K. Lee, and J. T. Newberry (1984). Earthquake data archiving andretrieval system: reference manual, U.S. Geol. Surv. Open-File Rept. 84-840, 159 p.Crane, G. R., W. H. K. Lee, and M. E. O’Neill (1985). Earthquake data archiving andretrieval system: user’s manual, U. S. Geol. Surv. Open-File Rept. 85-368, 24 p.Dewey, J. W. and D. W. Gordon (1983). Seismicity of the eastern United States andadjacent Canada, 1925-1976, U.S. Geological Survey, written commun., 1985.Gordon, D. W. (1985). Revised instrumental hypocenters and correlation of earthquakelocations and tectonics in the Central United States, U.S. Geological Survey, writtencommun., 1985.Gutenberg, B. and C. F. Richter (1954). Seismicity of the Earth, New York, Hafner PublishingCompany, 310 p.Jeffreys, H. and K. E. Bullen (1940), Seismological Tables, London, British Association forthe Advancement of Science, Gray Milne Trust, 50 p.Lee, W. H. K., D. L. Scharre, and G. R. Crane (1983). A computer-based system fororganizing earthquake-related data, U. S. Geol. Surv. Open-File Rept. 83-518, 28 p.Lienkaemper, J. J. (1984). Comparison of two surface-wave magnitude scales: A4 ofGutenberg and Richter (1954) and Ms of “Preliminary Determination of Epicenters”,Bull. Seism. Soe. Am., 74, 2357-2378.Milne, J. (1911). Catalogue of destructive earthquakes, British Association for the Advancementof Science, Report of 81st Annual Meeting, Appendix No. 1, 649-740.Usami, Tatsuo (1987). Study of historical earthquakes in Japan, this volume, p. 276-288.Xie, Yushou, (1987) Historical materials on Chinese earthquakes and its seismologicalanalysis, this volume, p. 162-170.