The sounds are rarely heard by them more than a few miles from the epicentre.
At the epicentre, the angle of emergence is a right-angle; at a great distance from the epicentre, it is nearly zero.
On the opposite side of the epicentre, the waves meet the Sierra de Ronda obliquely.
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.
The point of origin is called the centre or seismic focus, and the place on the surface vertically over it the epicentre.
A vertical line joining the epicentre and the focus was termed by Mallet the seismic vertical.
The intensity, or violence, of an earthquake is greatest in or near the epicentre, whence it decreases in all directions.
Lines drawn through places around the epicentre at which the shock arrives at the same moment are called coseismal lines.
In determining the position of the epicentre, Mallet's method was closely followed.
| 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. |
