Tectonic Development of Wadi Mi’ar Area, Sinai, Egypt: Implications of Low-Temperature Thermochronology Techniques

Mansour, Sherif

doi:10.21608/ajbas.2023.218033.1160

Tectonic Development of Wadi Mi’ar Area, Sinai, Egypt: Implications of Low-Temperature Thermochronology Techniques

Document Type : Original Article

Author

Sherif Mansour

Geology Department, Faculty of Science, Port Said University, Port Said 42522, Egypt

10.21608/ajbas.2023.218033.1160

Abstract

The basement rocks of Wadi Mi’ar, cropping out along the eastern flank of the Suez Rift, constitute part of the NE segment of the Neoproterozoic Arabian-Nubian Shield. The whole region is finally reshaped by the Suez Rift initiation during the Oligocene-Miocene. Low-temperature thermochronology techniques are capable of providing new insights into the tectonic development of the Suez Rift by reconstructing the uplifting response of its flanks. Therefore, we provide here thermochronological data for seven collected samples from the basement rocks of the Suez Rift’s eastern flank at Wadi Mi’ar. Zircon fission-track technique yielded cooling ages of 339 ± 10 Ma and 334 ± 9 Ma. While the apatite fission-track dated samples yielded ages between 26 ± 5 Ma and 21 ± 4 Ma. These cooling ages and the time-temperature modelling revealed three possible cooling pulses that represent exhumation events which were initiated as a response to three tectonic events; (1) the Neoproterozoic post-accretion erosional event, (2) the Devonian-Carboniferous Hercynian tectonic event, and (3) the Oligocene-Miocene Suez Rift. Furthermore, the Suez Rift initiation was accompanied by more than 3 km of rift flanks uplift to exhume samples from depths equivalent to 110 ˚C (apatite fission-track partial annealing zone) in the studied region. While the northern portion of the flank is dominated by older thermochronologic ages and modest rift flanks elevations.

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