MSK64 Seismic Intensity Scale

The Medvedev-Sponheuer-Karnik scale of seismic intensity was widely used in Europe and India starting in 1964. The MSK64 scale is based on typical masonry structures, many of which are very old. MSK64 was revised in 1981 (MSK81) and was superseded by the European Macroseismic Scale in 1998.

During those years it was found that some of the behavioral effects in MSK64, such as "panic" and "fright," as well as most of the natural geological effects, were not consistently useful. People's responses to earthquakes depend on many variables besides the actual shaking, and seismic effects on the landscape are even less predictable given the differences in soils, bedrock and structural geology from place to place. Therefore MSK64 ratings of historical earthquakes should be used skeptically; if reliable details on building damage are known, they should outweigh the behavioral and geological evidence. Because it doesn't match up well with modern scales, the MSK scale is not included in the master table of intensity scales.

Degree
Force
Behavioral effects
Structural effects
Geologic effects
  IImperceptibleNot felt
  IIVery lightFelt sporadically
  IIILightFelt only by people at rest
  IVModerateFelt indoors, many awakenedWindows vibrate
  VFairly strongWidely felt outdoorsInterior plaster cracks, hanging objects swing, tables shift
  VIStrongFrightDamage to chimneys and masonryIsolated cracks in soft ground
  VIIVery strongMany people flee their dwellingsSerious damage to buildings in poor condition, chimneys collapseIsolated landslides on steep slopes
  VIIIDamagingGeneral frightMany old houses undergo partial collapse, breaks in canalsChanges in wells, rockfalls onto roads
  IXDestructivePanicLarge breaks in substandard structures, damage to well-constructed houses, underground pipe breakagesCracks in ground, sand eruptions, widespread landslides
  XDevastatingGeneral panicBrick buildings destroyedRails twisted, landslides on riverbanks, formation of new lakes
  XICatastrophic
Few buildings remain standing, water thrown from canalsWidespread ground disturbances, tsunamis
  XIIVery catastrophic
Surface and underground structures completely destroyedUpheaval of the landscape, tsunamis

More earthquake magnitudes

More geology-related scales

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