Church bells and ground motions

Abstract

Although the primary objective of seismic stations is the recording of waves generated by natural seismicity, the sensors can detect vibrations generated by different sources of natural and anthropogenic origin. The interest in identifying these sources has increased in the last years with the use of background seismic vibrations to obtain images of the crustal structure by tomographic methods and to monitor different natural processes. We present here a very particular case of these types of sources, the bell ringing in churches to indicate the passage of time. In some particular cases, the vibrations generated by the ringing of the bells are recorded in seismic stations installed near the bell towers. We review different examples throughout Europe of this particular kind of seismic records to illustrate how the seismic records can provide information on the traditions followed to mark the hours in some European countries, which turn out to be very different. The objective is not only to publicize this curious records but also to show that bridges can be built between very different scientific disciplines, such as seismology and social sciences, since the seismic data offers a new tool to researchers interested in investigating ethnographic aspects related to how the passage of time is marked in different European cultures.