Scaglia Variegata Lombarda

Représentation et statut

Variantes historiques: Scaglia Variegata (Vonderschmitt 1940, Stockar 2003), Bunte Scaglia mit Fischschiefer (Vonderschmitt 1941), Scisti neri (Venzo 1954), Marne di Bruntino (Passeri 1969, Bersezio 1992), Scaglia variegata (Bichsel & Häring 1981), Lower Scaglia, Variegated Scaglia (Bitterli 1965), Scaglia Variegata Lombarda (Bernoulli et al. 2018)

Remarques nomenclatoriales: Corrisponde alle Marne di Bruntino (Passeri 1969).

Description: Strongly varying clay/marl/calcareous shale/argillaceous limestone sequence.

Unités hiérarchiquement subordonnées

Unités sus-jacentes

Unités sous-jacentes

Âge au sommet

Âge à la base

Paléogéographie

Bassin lombard

Termes génériques

Type de protolithe

Conditions de formation

open-marine (pelagic), quiet environment

Définition: Vonderschmitt Louis (1941) : Bericht über die Exkursion der Schweizerischen Geologischen Gesellschaft in den Süd-Tessin. Eclogae geol. Helv. 33/2 (1940), 205-219

Révision: Bichsel Matthias, Häring Markus O. (1981) : Facies evolution of Late Cretaceous flysch in Lombardy (northern Italy). Eclogae geol. Helv. 74/2, 383–420

p.388: The Scaglia variegata in the Bresciano, partly the lateral equivalent of the more calcareous Sasso della Luna to the west, consists predominantly of green, grey and red marls with intercalations of black argillites and belongs to the Upper Barremian-Cenomanian p.p. time-interval (Rossi 1975, Boni et al. 1970). Up-section, the Scaglia variegata is gradational with the Scaglia rossa which starts in the Cenomanian p.p. indicated by Rotalipora sp. and Praeglobolruncana stephani (Gandolfi) (Boni et al. 1970). At the top of this unit, the microfossil content indicates a Maastrichtian age with Globotruncana contusa (Cushman) and Globotruncana stuarii (de Lapparent). The Scaglia rossa consists of thin-bedded red and white marls and marly limestones with intercalated thin layers of resedimented pelagic material. In the Campanian, dated by Globotruncana stuartiformis Dalbiez and Globotruncana elevata (Brotzen), the Scaglia rossa is sporadically interrupted by turbiditic sandstones and marls, which correspond lithologically to the Bergamo Flysch. The thickness of the Scaglia rossa, measured along a road near Gussago (section 58, p. 413, Fig. 1, L), amounts to about 200 m.