Miocene rocks lie unconformably atop Eocene units, with almost the entire Oligocene missing. Some geologists suggest that the Oligocene and Lower Miocene are actually preserved in southern Lebanon as turbiditic sandstones. In the Miocene, the region underwent uplift, the seashore retreated and basalt flows blanked some parts of Lebanon and Syria. In particular, Syria experienced extensive basalt flows between 16 and 8 Ma. Some large marine deposits from the Miocene are located to the west of Mount Lebanon, while alluvial conglomerates covered limestones in Bekaa with up 600 meters of material.