GSSP of the Albian Stage
Definition
The GSSP for the base of the Albian Stage is defined at 37.4 m in the Col de Pré-Guittard section in the Vocontian Trough, southeastern France (44 29′ 47.78″N, 5 18′ 42.36″E), and is denoted by the FAD of the planktonic foraminifer Microhedbergella renilaevis.
Location
The Col de Pré-Guittard section lies 11 km northwest of Rémuzat and 19 km northwest of Rosans in the Départment of Drôme at 44 29′ 47.78″N, 5 18′ 42.36″E (Lambert coordinates 836,42;3248, 95; 1;25,000 topographic sheet Série Bleu 3138E, La Motte-Chalançon). It is reached by taking the D173 west from its junction with the D61, 2 km south of La Motte-Chalançon.
Sedimentology
The Col de Pré-Guittard section exposes 170 m of the Marne Bleues Formation, which ranges from the late Aptian to middle Albian and is composed of calcareous clays and marls that contain thin, locally developed and regionally continuous black shales and calcareous cemented levels. The base of the sequence is underlain by thin alternations of limestones and marls assigned to the Faisceau Fromaget.
Primary Marker
The lowest occurrence of the planktonic foraminifer Microhedbergella renilaevis, which is 37.4 m above the base of the section and 0.4 m above the base of the laminated Niveau Kilian bed.
Secondary Markers
Lowest occurrence of circular examples of the calcareous nannofossils Prediscosphaera columnata and Helicolithus trabeculatus at 29.5 m; extinction of the planktonic foraminiferan Paraticinella rohri (=Paraticinella eubejaouensis) at 34.75 m.
Correlation Events
Minimum value of 1‰ negative δ13C excursion at 37.4 m.