The areas covered in this work are the petroleum provinces of the Gulf of Suez in Egypt and the SE Coastal Troughs and the rifted Rukwa basin in the country of Tanzania, as they meant to represent the extreme ends of the Great East African Rift System. The study aims at investigating the influence of rifting on the processes of organic matter maturation, hydrocarbon generation, expulsion, and migration, as well as the influence of rifting on the preservation of accumulated hydrocarbons. The study identified the presence of sixteen generating and expelling troughs based on the results of thermal burial histories. All the source formations in the sixteen troughs reached top oil window and expelled their hydrocarbons at 10 million years before present (mmybp) and continued till present. Such timing post-dates the Early Miocene Mid Clysmic or Mid Rudeis "disturbing" event and the Late Miocene Messinian "quite" event, which suggest high Migration and accumulation efficiencies for hydrocarbons generated in these troughs.