Glossary

Ratio of the Fourier Amplitude Spectrum of horizontal (vectorial sum) and vertical components of ambient noise

A point in the Earth (also called earthquake focus) where the rupture of the rocks initiates during an earthquake.

The Hypocentral depth is the distance between the hypocenter and the epicenter of the earthquake (see Fault Distance).

The distance between the site and the earthquake hypocenter.

The historical record of ca. pre-XXth century earthquakes that have been parameterized in specific historical catalogues.

Feature of the station indicating the type of basement of the recording instrument (i.e. Building floor, Pillar, Building basement and Buried).

A two character code that identify the general sampling rate and the response band of the instrument (1th letter)

The recent and ongoing record of earthquakes that have occurred since the availability of modern-era seismometers (i.e. since the XXth century).

An event or process possibly detected by geological/geophysical tools and analyses that occurs between two significant earthquakes.

A zero-to-two alphanumeric code to identify the sensor location of a recording station

Cut-off frequency [Hz] of the low-pass filter.

The macroseismic intensity classifies empirically the earthquake severity according to an ordinal scale of the effects produced by the ground shaking.

The earthquake magnitude measures the intensity of the seismic event, based on an appropriate processing of the seismic signal.

Continuous ground motion constituting the background noise for any seismic measurement.

Microzonation is the identification of separate individual areas having different potentials for hazardous earthquake effects.