GC: n

S: http://scedc.caltech.edu/Module/shockmod.html (last access: 22 July 2016); https://www2.usgs.gov/faq/categories/9827/3346 (last access: 22 July 2016); http://earthquake.usgs.gov/learn/glossary/?term=aftershocks (last access: 22 July 2016).

N: 1. also after-shock, 1894, from after (Old English æfter “after, next, throughout, following in time, later,” from Old English of “off” + -ter, a comparative suffix; thus the original meaning was “more away, farther off”) + shock (1560s, “violent encounter of armed forces or a pair of warriors,” a military term, from Middle French choc “violent attack,” from Old French choquer “strike against,” probably from Frankish, from a Proto-Germanic imitative base).
2. A smaller earthquake that follows the main shock and originates close to its
focus. Aftershocks generally decrease in number and magnitude over time. (UN DHA)
3. An earthquake that follows a larger earthquake or main shock and originates at or near the focus of the larger earthquake.
4. Generally, major earthquakes are followed by many aftershocks, which decrease in frequency and magnitude with time. Such a series of aftershocks may last many days for small earthquakes or many months for large ones.
5. Aftershocks occur in the same general region as the mainshock and result from readjustments of stress at places along the fault zone.
6. aftershock: term used at Natural Resources Canada – Earth Sciences Sector.

S: 1. OED – http://www.etymonline.com/index.php?term=aftershock (last access: 22 July 2016). 2. GLOSS RW – http://reliefweb.int/sites/reliefweb.int/files/resources/4F99A3C28EC37D0EC12574A4002E89B4-reliefweb_aug2008.pdf (last access: 22 July 2016). 3 to 6. TERMIUM PLUS – http://goo.gl/Lfqpwh (last access: 22 July 2016).

GV: after-shock

S: OED – http://www.etymonline.com/index.php?term=aftershock (last access: 22 July 2016)

SYN:
S:

CR: seism