What is Rotational Seismology?
Rotational Seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions and ambient vibrations.
To describe the situation during vibration generated by an earthquake, the general motion of particles or a small volume in a solid body, can be divided into three parts: translation (along the x, y, and z axes), rotation (about the x, y, and z axes), and strain (e.g. Båth, 1979; Teisseyre et al., 2006).
Rotational ground motion has been ignored for centuries due to a widespread belief that rotation is insignificant in measuring it but recently it is believed that rotational signals may contain additional valuable information for studying wave propagation; in addition, rotational ground motion may be important in the excitations of certain engineering structures.
According to the introduction to a special issue of the Bulletin of the Seismological Society of America, rotational seismology has become an emerging field for the study of all aspects of rotational ground motion induced by earthquakes, explosions, and ambient vibrations. This domain has attracted the attention of researchers from a wide range of geophysical disciplines and structural engineers.
Tellus R is the basis for constructing the most modern seismic systems, recording all 6 components of mechanical motion.
It has a high sensitivity for the detection of rotational modes of earthquakes, a wide dynamic and frequency range.
A characteristic feature of Tellus R is low noise with minimal power consumption, which is a significant advantage over electro-mechanical, fiber-optic and other types of rotational motion sensors. This device has a calibration input, which allows to perform periodic calibration without use of special expensive equipment. The device is capable of operating at any orientation in space over a wide range of temperatures.
A complete seismic station
You can build your complete seismic station using an ATLAS 9-channels and get information from the force balance accelerometer (LTFB155), the very broad band velocimeter (Tellus FS) and the rotational sensor (Tellus R)