Hypocenter
The hypocenter (from the Greek ὑπό hypó "below, below" and κέντρον kentron "center"), also called the quake focus or seismic source , is the point from which an earthquake emanates.
In seismology, the hypocenter is characterized by the focal depth and the position of the epicenter on the earth's surface. The hypocenter is the point from which the earthquake emanates, i.e. corresponds to the origin of the fracture surface . The epicenter, on the other hand, is its vertical projection onto the earth's surface.
The location of the hypocenter can be determined by examining the transit times of earthquake waves at seismological stations distributed over the earth . As measurements on waves are concerned, this measurement is subject to a lack of clarity: the longer the wavelength , the less precise the location. Since severe earthquakes in particular give off most of their energy as long-period waves, their spatial source cannot be precisely measured.
The spatial definition of the hypocenter is further limited by the fact that earthquakes often do not originate from point sources, as is usually assumed to simplify matters, but from fault lines. However, the hypocenter is assumed to be in the nucleation point of the fracture zone , i.e. at the place where the shear fracture begins.
literature
- Götz Schneider: Earthquakes - An introduction for geoscientists and civil engineers. Spektrum Akademischer Verlag, Munich 2004, ISBN 3-8274-1525-X .
Web links
Individual evidence
- ^ Peter M. Shearer: Introduction to Seismology. Cambridge University Press, New York 1999, ISBN 978-0-521-66953-5 .