Bekaa is a medium altitude plain, with an average ground elevation of , bounded by Mount Lebanon in the west and the Anti-Lebanon mountains to the east. Based on gravity surveys in the late 1990s, it was concluded the Bekaa sedimentary basin to be up to thick, probably tied to the uplift associated with the Levant Fracture System. Most of the sediments beneath the plain are lacustrine or continental deposits, cloaked in thick Pliocene and Quaternary deposits, including alluvial fans.