depending on context, the support base would be where the troops are assembled for back-up purposes while the staging ground is described as an area where troops (either in reality or in the figurative sense) are assesmbled and readied prior to a new operation or mission
La Base Arrière ? Comme son nom l’indique c’était là qu’était entreposé tout un tas de matériel. Je revois une quantité incroyable de casques empilés les ...
cessenon.centerblog.net/1834848-Ma-periode-a-la-Base-Arriere - 21k
Le Hezbollah a-t-il installé une base arrière au Togo ? Date de parution : lundi 6 mars 2006. Du même auteur. infosplusgabon · Bird flu spreads to Cameroon, ...
www.infosplusgabon.com/article.php3?id_article=221 - 31k
Patriots Point's Vietnam Naval Support Base Camp features many of the various ... The display also is home to a Sea Cobra attack helicopter and many of the ...
www.patriotspoint.org/exhibits/vietnam_base/ - 14k
In one attack on a highway near Balad, US soldiers were ambushed three times ... LSA Anaconda, the largest support base in Iraq, is reportedly nicknamed ...
www.globalsecurity.org/military/world/iraq/balad-ab.htm - 34k
http://www.csmonitor.com/2001/0926/p1s2-wosc.html
http://www.nytimes.com/2007/02/20/world/africa/20tunisia.htm...
http://www.cnn.com/WORLD/europe/9904/16/kosovo.refugees.02/

Just an idea.