Strong
Strong shaking · Light damage potential
Felt by all; many frightened. Some run outdoors. Walking feels unsteady. Damage slight.
Effects
People & Response
- Felt by everyone; many frightened
- Many run outdoors
- Walking feels unsteady
- Some difficulty standing
Objects & Furnishings
- Windows and dishes fall and break
- Books and objects fall from shelves
- Small bells ring loudly
- Heavy furniture moved or overturned
Structures & Environment
- Plaster falls from walls and ceilings
- Chimneys crack
- Trees shaken slightly to moderately
- Slight damage to ordinary buildings
Also at this level, in other versions of the scale
- Liquid set in strong motion Wood & Neumann (1931), Bulletin of the Seismological Society of America 21, 277-283
- People and animals alarmed New Zealand Modified Mercalli scale, GeoNet (MM6)
Observed at this level
Camera footage our reviewer rated VI from the effects it shows. All 9 clips at VI · Random clip at VI
Simulated at this level
Our physics animations of familiar objects, shaken by the ground motion estimated for a city at intensity VI.
Video Example
Descriptions are verbatim from the USGS MMI Scale, based on Wood & Neumann (1931) and Richter (1958). Source: USGS Modified Mercalli Intensity Scale .
Instrumental intensity values and PGA/PGV ranges from USGS ShakeMap V4 Technical Documentation (Worden et al.). Intensity Lab reports MMI derived via the Worden et al. (2012) GMICE, interpolated from USGS ShakeMap. PGA/PGV ranges are approximate; actual values overlap between adjacent levels.