An earthquake that follows
the largest shock of an earthquake sequence. Aftershocks are smaller than
the mainshock and within 1–2 fault lengths distance from the mainshock
fault. Aftershocks can continue over a period of weeks, months, or years.
In general, the larger the mainshock, the larger and more numerous the aftershocks,
and the longer they will continue.
|The Landers fault (red lines at left) and the Hector
Mine fault and its aftershocks (red lines and circles at right). The
Hector Mine earthquake was a magnitude 7.1, and it produced thousands
of aftershocks. Image credit: Egill Hauksson, Caltech
AND PLANETARY SCIENCE
Source: U.S. Geological