Zanclean Gilbert-Type Fan Deltas In The Turnu Severin Area (Dacian Basin, Romania). A Critical Analysis

Abstract

Abstract. The critical analysis of the Gura Văii – Turnu Severin – Izvoru Bârzii Gilbert-type deltas concentrated on the deltaic architecture and the age of the deltaic deposits, referring especially to the conglomeratic sediments considered the proximal foreset unit of the Gilbert-type fan deltas. It reveals the lack of evidences necessary to demonstrate the existence of the three units (foreset, bottomset and topset beds) which define a Gilbert-type delta. Although there are convincing data for its tectonic<br> origin, the homoclinal structure of these deltaic deposits was considered, with no argumentation, as a primary structure generated through the deltaic progradation.<br> The age of the rudaceous deposits in the area Gura Văii – Turnu Severin – Izvoru Bârzii, representing the core of the two outlined Gilbert deltas, was considered Zanclean (Bosphorian) by Clauzon et al. (2005) and Suc et al. (2011), rejecting the Badenian – Sarmatian (s.l.) age formerly attributed (Marinescu, 1978 and the references herein). The critical examination of these two concepts pointed out the paleontological and stratigraphic proofs which substantiate the Badenian-Sarmatian (s.l.) age,<br> in contrast with the lack of evidences in favor of the Zanclean age. The Gilbert-type fan deltas figured by Clauzon et al. (2005) and Suc et al. (2011) in the area of the present-day Danube River course (area Gura Văii – Turnu Severin – Izvoru Bârzii), closely downstream of the Iron Gates, represents one of the main arguments of these authors for the action of the Messinian crisis in the Dacian Basin. Taking into consideration the importance of this concept for the understanding of the Dacian Basin<br> evolution, this paper undertakes a critical analysis of the factual data which generated the concept of the Gilbert-type fan deltas in the Turnu Severin area.