Italian geologist, seismologist, volcanologist and priest. Who was Giuseppe Mercalli e what does the scale measure invented by him?
Who was the seismologist Giuseppe Mercalli?
Giuseppe Mercalli was born on May 21, 1850. He studied at the Monza seminary for literary and scientific culture and was a pupil of the geologist Antonio Stoppani. In 1874 he graduated in Natural Sciences and subsequently began teaching natural sciences at the Monza seminary. During the years between 1880 and 1913 he conducted an intense research activity and devoted himself to the study of alpine glacial deposits in Lombardy. He became a teacher of religious secondary schools in Monza, for which he also makes school texts.
His greatest contributions in the seismic field were the conception of the Mercalli scale, a very useful tool for classifying the intensity of an earthquake, and the realization of the first seismic map of the Italian territory.
The Mercalli scale
What are the characteristics of the Mercalli scale? What kind of quantity does it measure?
La Mercalli scale it is used to measure themacroseismic intensity of an earthquake through the observation of damage and environmental changes produced by a seismic event.
What is the difference between the Mercalli scale and the Richter scale?
The Mercalli scale, unlike the Richter scale which tends to measure the energy that the earthquake releases expressed in magnitude, measures the intensity of an earthquake based on the damage to buildings and the human perception of the seismic phenomenon and evaluates it qualitatively rather than quantitatively.
The grades that make it up are the following:
La Mercalli scale is not defined in relation to physical quantities, with objectively quantifiable measurements such as shock amplitude, peak velocity, acceleration, or period and has, therefore, the advantage of being usable even in the absence of specific instrumentation and that it can also be applied to descriptions of earthquakes that occurred in historical periods, during which they did not exist seismometers suitable for recording the tremors.