Timing of mid-Cretaceous carbonate platform depositional cycles, northern Sinai, Egypt

Palynology of the Mid-Cretaceous Malha and Galala Formations, Gebel El Minshera, North Sinai, Egypt

“…The Galala Formation was dated as late Cenomanian through early Turonian by Aboul Ela et al (1990a) based on earlier paleontological studies (e.g., Awad and Fawzi, 1956;Fawzi, 1960Fawzi, , 1963Abdou and Fawzi, 1966), whereas Issawi et al (2009) assigned the entire Galala Formation to the Cenomanian in their regional assessment of this formation. Bachmann and Kuss (1998) and Bachmann et al (2003) assigned a late Albian age to the lower part of their Unit B, which appears to be partly equivalent to the lower part of the Galala Formation. They placed the upper Albian-lower Cenomanian boundary and the lower-middle Cenomanian boundary at 145 m and 220 m above the base of their section, respectively, again using a combination of benthic foraminifers, ostracodes, and sequence stratigraphy.…”

“…The upper part is a white-to yellowish-white, poorly sorted and fractured sandstone. The section depicted by Bachmann and Kuss (1998) and Bachmann et al (2003) was divided into Unit A (,35 m thick) overlain by Unit B ($270 m thick). Their Unit A is delta dominated but has more variable lithology than what we define as the Malha Formation and includes beds of dolomitic limestone; this lithology is difficult to reconcile with our section but presumably reflects lateral variability within this deltaic setting.…”

“…The boundary between units A and B is indistinct, apparently owing to missing deltaic sediments (Bachmann et al, 2003, p. 138). Bachmann et al (2003) assigned Unit A to the upper middle Albian and the lower part of Unit B to the upper Albian, based on integrated evidence from benthic foraminifers, ostracodes, and sequence stratigraphy.…”

“…Aboul Ela et al (1990aEla et al ( , 1990b constrained the age of the formation from well-dated, subjacent Bajocian-Callovian deposits and superjacent marine Cenomanian deposits of the Galala Formation. More recent integrated biostratigraphic and sequence-stratigraphic studies by Bachmann and Kuss (1998) and Bachmann et al (2003), however, have indicated a late middle and late Albian age for deposits approximately equivalent to the Malha Formation.…”

“…During the midCretaceous, northern Sinai was a carbonate ramp that developed along the southern margin of the Tethyan Ocean (Wanas, 2008). The Gebel El Minshera section represents the southern, more proximal part of this ramp, in which the siliciclastic, delta-dominated Malha Formation passes upwards into the carbonate-dominated Galala Formation (Bachmann and Kuss, 1998;Bachmann et al, 2003). The area has been tectonically active from the Early Cretaceous to the Eocene owing to regional compression in northeastern Egypt (Shaaban et al, 2006).…”