The debate about a precise stratigraphical age of the exposed limestones in the Hâqel and Hâdjoula quarries is long. Geological studies on the Cretaceous outcrops in Lebanon started with Botta (1833), who investigated the lithology of the sediments in the Hâqel area. Lewis (1878) and Fraas (1878) postulated a Turonian age for both Hâqel and Hâdjoula. Patterson (1967) and Hückel (1970) later recognized a Cenomanian age of these localities. Patterson (1967) estimated a Mid-Cenomanian age for both Hâqel and Hâdjoula on the basis of fish fauna, whereas Hückel (1970) placed the beds at Hâqel as Early Cenomanian based on the record of the foraminifer Orbitolina concava concava and the index ammonite Mantelliceras mantelli already reported by Zumoffen (1926).
Biostratigraphical studies of Dubertret (1959, 1966) and Saint-Marc (1974) determined the sequences at Hâqel and Hâdjoula to be Early Cenomanian. Hemleben (1977), on the other hand, again dated them as Late Cenomanian in view of the assemblage of the planktonic foraminifera Praeglobotruncana stephani, Rotalipora cushmani and Rotalipora greenhornensis. More recently, Wippich and Lehmann (2004) confirmed a Late Cenomanian age for both Hâqel and Hâdjoula owing to the presence of the ammonite Allocrioceras cf. annulatum, which is a member of the lower Upper Cenomanian Sciponoceras gracile Zone in the Western Interior of USA and the Metoicoceras geslinianum Zone of the international standard.