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Catalogue of Earthquakes in Finland, Sweden, and the Baltic Shield Area of the USSR Recorded by Finnish and Swedish Seismograph Stations. Time Period: 1963-1979
DDC:
550 - Earth sciences
Abstract:
Station corrections have been introduced into the M"SUB L"-scale hitherto used for Baltic Shield earthquakes. This increases the consistency of the scale. The new formula has the design: M"SUB L"(UPP) = log a + log V(T) + 1.61 log DELTA - 3.22 + C"SUB I" + C"SUB s", where a = ground amplitude (mu m), V(T) = Wood-Anderson short-period seismometer magnification at period T, DELTA = epicentral distance (km), C"SUB I" = instrument type constant and C"SUB s" = station correction. The formula is valid for Benioff and Grenet seismograph stations in Finland and Sweden. An extension of the magnitude scale to distances as small as 30km has been made.-from Authors