Abstract
Facies analysis and depositional environment investigation coupled with the sequence stratigraphy gave a precise picture on the depositional framework and evolution of any succession. This study is ground on litho- and microfacies analysis and stratigraphical investigation to conclude the depositional and sequence stratigraphic framework of the Miocene rocks units along the Cairo-Suez Road. The studied depositional sequences of Burdigalian-Langhian age can be differentiated into two main stratigraphic units; A lower siliciclastic unit revealing lagoonal (intertidal lagoons, intertidal estuarine), and inner ramp facies, termed as Gharra Formation, and lies unconformably over the Oligocene continental sediments of Gebel Ahmar Formation. This unit is conformably overlain by the middle Miocene marine-nature sediments of Genefe Formation., revealing middle, to outer ramp facies. This depositional sequence was initiated as a result of the Miocene sea first advance over northern Egypt, including the study area. Retrogradational parasequences were stacked successively to evolve the lowstand system tract (LST), followed by the transgressive surface (TS), that matched the contact between Gharra, and Genefe formations. A deeper accommodation zone was formed as a result of the middle Miocene sea level rise, due to a tectonic subsidence, resulting in the deposition of Genefe Formation over the transgressive surface (TS), representing the transgressive system tract (TST).