Mercalli intensity scale
Escala de intensidad de Mercalli
- Date
- 1902 · confidence medium
- Place
- Milan, Lombardy, Italy
- Credited to
- Giuseppe Mercalli
- Field
- Knowledge & symbols
⚠️ Disputed: the sources disagree.
What it is
A scale of earthquake intensity in ten (later twelve) degrees based on the effects observed on people, objects and buildings, not on instruments. It complements magnitude, which measures energy, with a measure of damage at each place.
The scale derives from Rossi-Forel's (1883); Mercalli's version (1902) was extended by Cancani (1904) and Sieberg (1923), and modified by Wood and Neumann (1931). It is placed in Milan because of Mercalli's work at that city's seminary; the location is approximate.
What it led to
- intensity and seismic damage maps
- the Modified Mercalli scale (1931) and EMS-98
- earthquake-resistant building codes based on observed damage