Medvedev–Sponheuer–Karnik scale

The Medvedev-Sponheuer-Karnik scale (MSK-64) is a macroseismic intensity scale.

The scale was first published by V. Medvedev (USSR), W. Sponheuer (East Germany), and V. Karnik (Czechoslovakia) in 1964 and became widely used in Europe between 1964 and 1996. It received minor modifications in the mid-1970s and early 1980s. The European Seismological Commission (ESC) used MSK-64 as a basis for the development of the European Macroseismic Scale, which is now a Europe's de facto standard for evaluation of earthquakes.

MSK-64 is still widely used in Russia and other member countries of the Commonwealth of Independent States.

The Medvedev-Sponheuer-Karnik scale is somewhat similar to the Modified Mercalli intensity scale used in the United States. Just like the Mercalli scale, MSK-64 has 12 levels of intensity, which describe the effects of earthquakes on natural and man-made structures:

1. Imperceptible - Not felt, registered only by seismographs.
2. Very light - Felt only by people at rest.
3. Light - Felt sporadically.
4. Moderate - Felt indoors by many people.
5. Fairly strong - Widely felt outdoors. Buildings tremble.
6. Strong - Visible damage to masonry structures, fine cracks in plaster. Isolated cracks on ground surfaces.
7. Very strong - Serious damage to older buildings, masonry chimneys collapse. Small landslides.
8. Damaging - Older structures partially collapse or considerably damaged. Substantial subsoil shifts, rockfalls.
9. Destructive - Substandard structures collapse, substantial damage to well-constructed structures, underground pipelines raptured. Ground fracturing, widespread landslides.
10. Devastating - Masonry buildings destroyed, infrastructure crippled. Massive landslides, formation of new water bodies.
11. Catastrophic - Most buildings and structures collapse. Widespread ground disturbances, tsunamis.
12. Very catastrophic - All surface and underground structures completely destroyed. Landscape generaly changed, rivers change paths, tsunamis.

Other seismic intensity scales

Unlike the magnitude scales (such as the Richter scale), which measure the amount of seismic energy released at the hypocenter of the earthquake, intensity scales are used to assess the effects of ground motions on people, buildings, and objects of nature. Below is an incomplete list of other seismic intensity scales.

• European Macroseismic Scale
• Mercalli scale
• Omori scale
• Rossi-Forel scale
• Shindo scale

External links

• Seismic intensity maps of Russia based on MSK-64