In determining the position of the epicentre, Mallet's method was closely followed.
The sounds are rarely heard by them more than a few miles from the epicentre.
Even at Tokio, which is about 175 miles from the epicentre, the tilting of the ground was very noticeable.
The portion of the earth's surface which is vertically above the seismic focus is called the epicentre.
The method employed by him for the purpose is no less simple theoretically than that used for locating the epicentre.
At the epicentre, the angle of emergence is a right-angle; at a great distance from the epicentre, it is nearly zero.
There are, however, several lines of direction which can have no connection with this epicentre.
On the opposite side of the epicentre, the waves meet the Sierra de Ronda obliquely.
In the neighbourhood of the Rantowles epicentre, the isoseismals in both Figs. 28 and 29 are elongated in form.
The point of origin is called the centre or seismic focus, and the place on the surface vertically over it the epicentre.
| epicenter The point on the Earth's surface that is directly above the focus (the point of origin) of an earthquake. The epicenter is usually the location where the greatest damage associated with an earthquake occurs. See Note at earthquake. |
