Time series (Orbital cycles) analysis of the latest Cenomanian - Early Turonian sequence on the southern Tethyan margin using foraminifera

Mohamed Soua (1)

1 ETAP - Entreprise Tunisienne d'Activités Pétrolières

Time series analysis has been performed for the first time on the Cenomanian-Turonian sequence in Central Tunisia in order to shed light on its Milankovitch-like cyclicity. This analysis was applied to two foraminiferal genera: the biserial Heterohelix, an oxygen-minimum zone (OMZ) dweller, and the triserial Guembelitria, a eutrophic surface dweller. Average sedimentary rates and the duration of the OAE2 in each studied section were estimated. The fluctuations in abundance of these two opportunistic species can be related mainly to both precessional (ca. 20 kyr) and eccentricity (100 and 400 kyr) cyclicity suggesting that changes in surface water fertility were linked to climate changes in the the Milankovitch frequency band

Mots clés: Heterohelix spp; Guembelitria spp; Cenomanian-Turonian boundary; time series analysis; cyclostratigraphy; Milankovitch cyclicity; Heterohelix spp.; Guembelitria spp.

Domaines: Géologie appliquée

Mohamed Soua. Time series (Orbital cycles) analysis of the latest Cenomanian - Early Turonian sequence on the southern Tethyan margin using foraminifera. Geologica carpathica, 2010, 61 (2), pp.111--120. ⟨10.2478/v10096-010-0004-5⟩. ⟨hal-00626297⟩