The molluscan assemblage from a bulk sample from the Member of Ganzole, belonging to the Monte Adone Formation, was studied for biostratigraphic and paleoecological purposes. The Ganzole Member, referred in the literature to the Piacenzian, consists of intercalating sandy and pelitic beds, cropping out in the Sasso Marconi area (Bologna, central Italy). The bulk sample, with a volume of 50 dm3, was subdivided into 48 subsamples, one of which (C1, volume ca. 1000 cm3) was used for studying the molluscan fauna. The assemblage consists of 103 species of gastropods, bivalves and scaphopods, for a total of 1493 specimens. Its composition is indicative of warm waters, sandy-muddy substrates with debris, between the infralittoral and the circalittoral zones. Biocenotically, the assemblage is indicative of an ecotone between the SFBC and DC-DE paleobiocoenoses. The occurrence of species which became extinct in the Late Pliocene, such as Bathytoma cataphracta (Brocchi, 1814), Bela nitida Pavia, 1975, Eulimella subalpina (Sacco, 1892) and Turbonilla pliopupoides (Sacco, 1892), together with the occurrence of Venus foliaceolamellosa (Dillwyn, 1817) and Pelecyora gigas (Lamarck, 1818), whose disappearance seems to be related to the Pliocene cooling, point to an Early-Middle Piacenzian age.
La malacofauna pliocenica di "Le Conchiglie", Lagune di Sasso Marconi (Bologna)
BELLAGAMBA, MARIELLA;CALDARELLA, MARIA BENEDETTA;
2013
Abstract
The molluscan assemblage from a bulk sample from the Member of Ganzole, belonging to the Monte Adone Formation, was studied for biostratigraphic and paleoecological purposes. The Ganzole Member, referred in the literature to the Piacenzian, consists of intercalating sandy and pelitic beds, cropping out in the Sasso Marconi area (Bologna, central Italy). The bulk sample, with a volume of 50 dm3, was subdivided into 48 subsamples, one of which (C1, volume ca. 1000 cm3) was used for studying the molluscan fauna. The assemblage consists of 103 species of gastropods, bivalves and scaphopods, for a total of 1493 specimens. Its composition is indicative of warm waters, sandy-muddy substrates with debris, between the infralittoral and the circalittoral zones. Biocenotically, the assemblage is indicative of an ecotone between the SFBC and DC-DE paleobiocoenoses. The occurrence of species which became extinct in the Late Pliocene, such as Bathytoma cataphracta (Brocchi, 1814), Bela nitida Pavia, 1975, Eulimella subalpina (Sacco, 1892) and Turbonilla pliopupoides (Sacco, 1892), together with the occurrence of Venus foliaceolamellosa (Dillwyn, 1817) and Pelecyora gigas (Lamarck, 1818), whose disappearance seems to be related to the Pliocene cooling, point to an Early-Middle Piacenzian age.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
