Depositional patterns of the Cambrian Araba Formation along the Taba-Naqab road, east-central Sinai, Egypt: paleoenvironmental reconstruction and correlation in Northern Gondwana

Abstract

This study investigates the facies analysis and sequence stratigraphy of the Cambrian Araba Formation along the Taba-Naqab Road in east-central Sinai, Egypt. The sediments of the Araba Formation were deposited in diverse environments, including braided fluvial, floodplain/overbank, intertidal to subtidal, and shallow marine to offshore environments. These depositional settings are consistent with patterns observed in Northern Gondwana. The Cambrian strata in the African and Arabian segments of Northern Gondwana have been roughly correlated lithostratigraphically, correlation based on sequence stratigraphy remains limited. Two depositional sequences (SQ1 and SQ2) have been identified within the Araba Formation. These sequences, along with their internal divisions, can be correlated with lithostratigraphic units and existing depositional sequences in the surrounding Middle Eastern regions. The lowstand systems tract (LST₁) of SQ1 can be correlated with the lower Cambrian lowstand/regressive Salib (Jordan), Siq (Saudi Arabia), and Amudei Shelomo (Israel) formations. Similarly, the transgressive systems tract (TST₁) of SQ1 can be correlated with the middle Cambrian transgressive Tayana and Numayeri members of the Burj Formation (Jordan) and the Timna Formation (Israel). In contrast to the continuous sedimentation observed in Jordan, Saudi Arabia, and Israel during the late middle and late Cambrian, the Araba Formation experienced an abrupt basinward shift of facies. This shift, likely induced by local tectonic uplift of the Arabian-Nubian Shield (ANS), resulted in the formation of the falling stage systems tract (FSST₁) and the development of a subaerial unconformity at the top of SQ1. Subsequently, a renewed rapid basin subsidence and relative sea-level rise allowed deposition of the TST₂ of SQ2.