New Evidence of Transcurrent Movements in Red Sea Area and Petroleum Implications

Abstract

New evidence, derived from the displaced positions of two pairs of prominent shear zones--Abu Masarib (Arabia)-Duwi (Africa) and Wadi Alhamd (Arabia)-Wadi Hafafit (Africa)-indicates that Arabia has moved northward about 150 km relative to Africa along the Red Sea rift. The displacement of the shear zones was observed initially in photographs of the Red Sea area taken during Gemini earth-orbiting missions and has been substantiated subsequently by data derived from the geologic literature. The movement also must have displaced the basement block in northwestern Arabia (Maqna block) from its original position at the southern end of the Gulf of Suez to its present position at the Gulf of Aqaba. Hence it is evident that Maqna block and the adjacent offshore area south of Sinai Peninsula were part of a structural unit (Greater Gulf of Suez basin) and thus are similar in sedimentary and tectonic history and petroleum potential. Gemini pictures show that the Red Sea structures are dominated by five major fissure systems; many show evidence of being transcurrent. Certain fissures trending WNW-ESE appear to bear a spatial relation to most oil occurrences in the Gulf of Suez.