REASSESSING THE BIOSTRATIGRAPHY AND THE PALEOBATHYMETRY OF THE GONFOLITE LOMBARDA GROUP IN THE COMO AREA (NORTHERN ITALY) ...

• Main Authors: TREMOLADA, FABRIZIO, GUASTI, ELISA, SCARDIA, GIANCARLO, CARCANO, CIPRIANO, ROGLEDI, SERGIO, SCIUNNACH, DARIO
• Format: Article in Journal/Newspaper
• Language: English
• Published: Università degli Studi di Milano 2010
• Subjects: Gonfolite Lombarda Group; Biostratigraphy; Calcareous nannofossils; Foraminifers; Southern Alps; Cenozoic; Italy; Planktonic foraminifera
• Online Access: https://dx.doi.org/10.13130/2039-4942/5939; http://riviste.unimi.it/index.php/RIPS/article/view/5939

Calcareous nannofossil and foraminiferal analyses have been carried out on outcrops from the type-area of the Gonfolite Lombarda Group (Como, northern Italy). In these marine fine- to coarse-grained clastics, rapidly accumulating at the southern front of the uprising Alpine range during the Oligo-Miocene, a scarce, but reliable, sequence of calcareous nannofossil events has been observed, allowing to refine the previous age assignments. Planktonic foraminifera were found to be extremely rare and provided limited biostratigraphic information. The Villa Olmo Conglomerate and the Chiasso Formation contain the Last Occurrence (LO) of Sphenolithus distentus and the First Occurrence (FO) of Triquetrorhabdulus carinatus, which are characteristic of the nannofossil zones NP24 and NP25 (Chattian), respectively. The lower part of the Como Conglomerate was deposited during the zone NP25, whilst the upper part of the Como Conglomerate straddles the Chattian/Aquitanian boundary in zone NN1. The deposition of the Prestino ... : Rivista italiana di Paleontologia e Stratigrafia, Vol 116, No 1 ...