Un periodo sismico nella zona dei Monti della Tolfa

• Main Author: M. DE PANFILIS
• Format: Article
• Language: English
• Published: Istituto Nazionale di Geofisica e Vulcanologia (INGV) 1969-06-01
• Series: Annals of Geophysics
• Online Access: http://www.annalsofgeophysics.eu/index.php/annals/article/view/5091

On July 2nd, 1969, at about 07h56m (Greenwich Mean<br />Time), an intense earthquake shock, followed by a series of minor ones,<br />occurred in the Tolfa Mountains, located between the Bracciano Lake and<br />the littoral of Civitavecchia. The phenomenon was of a particular interest,<br />since it occurred in an area that until present days had seemed to be rather<br />quiet seismically.<br />With the present note, on the base of thorough investigations conducted<br />in the hardest-hit area and in all places where the seismic movement had<br />been perceivsd by the inhabitants, the coordinates of the epicenter are<br />determinated and the macroseismic propagation of the main shock is represented<br />with the map of isoseismical lines. With the data obtained from seismograms recorded by the stations<br />of Rome and of Monte Porzio Catone, the hypocentral depth and the origin<br />time of the main shock have been calculated.<br />Tliis is followed by a description of the seismic activity in the region<br />extending around the area of the Tolfa Mountains.