Επαφή | RSS | EN | DE | EL | ES | FR | IT | RU

The Modified Mercalli Intensity Scale (MMI)

In short, the intensity of a quake is its effect on the ground at a given point.
While the perhaps more familiar parameter of magnitude is a measure of the energy that an earthquake releases, the "intensity" of a quake is a measure of the ground shaking severity at a given point. It is thus depending primarily on the earthquake's magnitude and distance from where the quake occurred inside the earth (hypocenter), i.e. a combination of distance from its epicenter and depth.
The larger a quake, the closer to the epicenter and the shallower the quake, the more shaking is noticeable on the ground.
Intensity of earthquakes at given locations is thus a much more appropriate value to asses potential damage etc . It is most commonly measured on the so-called Modified Mercalli Intensity scale, or short as MMI given in Roman numbers from I to X (1-10), where I describes the lowest possible shaking perceived by only the most sensitive persons under favorable conditions, while intensities of IX and X are catastrophic ground movments that would level (nearly) every structure.
The MMI is based on an original scale presented and used by Italian seismologist Giuseppe Mercalli's in 1902, and adapted in 1931 by the American seismologists Harry Wood and Frank Neumann.
The Mercalli Intensity Scale explained
The Mercalli Intensity Scale explained
Try our free app!
Volcanoes & Earthquakes - new app for Android
Android | iOS version

Support us - Help us upgrade our services!

We truly love working to bring you the latest volcano and earthquake data from around the world. Maintaining our website and our free apps does require, however, considerable time and resources.
We need financing to increase hard- and software capacity as well as support our editor team. We're aiming to achieve uninterrupted service wherever an earthquake or volcano eruption unfolds, and your donations can make it happen! Every donation will be highly appreciated. If you find the information useful and would like to support our team in integrating further features, write great content, and in upgrading our soft- and hardware, please make a donation (PayPal or Online credit card payment).

Planned features:
  • Improved multilanguage support
  • Tsunami alerts
  • Faster responsiveness
Thanks to your past donations, these features have been added recently:
  • Design upgrade
  • Detailed quake stats
  • Additional seismic data sources
Download and Upgrade the Volcanoes & Earthquakes app to get one of the fastest seismic and volcano alerts online:
Android | IOS
Thank you!
Sources: VolcanoDiscovery / VolcanoAdventures and other sources as noted.
Use of material: Most text and images on our websites are owned by us. Re-use is generally not permitted without authorization. Contact us for licensing rights.
Volcanoes & Earthquakes
VolcanoDiscovery Home
Ηφαίστεια | Σεισμοί | Photos | News | App
Adventure & Study Travel
Tours to Volcanoes and Volcanic Areas: walking tours, photo tours, study tours
Tours & Dates | FAQ | About us
Get our newsletter!
Company info
Contact | Legal info | Terms & conditions
Follow us
Follow us on facebook Follow us on Instagram Follow us on Twitter Visit our Youtube channel
EN | DE | EL | ES | FR | IT | RU
VolcanoDiscovery GmbH, Germany, Reg. nr.: HRB 103744, EU Tax Id: DE 310 395 322 owned and created by
Dr. Tom Pfeiffer, volcanologist, volcano photographer, tour organizer member of
IAVCEI
Volcanological Society
Ecotourism Greece
Insured by R+V
VolcanoDiscovery © 2004- All Rights Reserved | Privacy - cookie settings