Hydrocarbon-derived imprints in olistostromes of the Early Serravallian Marnoso-arenacea Formation, Romagna Apennines (northern Italy)

Sediment instability related to fluid venting in Miocene authigenic carbonate deposits of the northern Apennines (Italy)

“…Particular cold-seep communities (modioloid mussels, lucinid, vesicomyid and solemyid clams) are described from Italian chemoherms (Berti et al 1994;Taviani 1994), and geometry, composition and internal structures similar to modern counterparts were reported by Fontana (1998, 1999). Authigenic carbonates range from small, centimetre-to decimetre-thick concretions, slabs and crusts to large carbonate mounds and build-ups up to 25-30 m in height.…”

Hydrocarbon seep-carbonates of a Miocene forearc (East Coast Basin), North Island, New Zealand

“…Berti et al, 1994;Clari et al, 1994;Fontana, 1999, 2002;Conti et al, 2004). The intrinsic mobility of the developing orogenic belt caused the dynamic gas-related fracturing of older rocks, collapsing and squeezing of basinal muds, and lateral/vertical migration of methane from previously confined source areas .…”

“…Berti et al, 1994;Conti and Fontana, 1999, 2005Conti et al, 2004;Lucente and Taviani, 2005), and are discussed further in Section 5.4 with respect to New Zealand examples.…”

Chemosymbiotic bivalves from Miocene methane-seep carbonates in Italy

“…Other authors (Krylova and Janssen, 2006;Krylova and Sahling, 2010) have separated these species into the genera Archivesica, Phreagena, and Akebiconcha, but they have not consistently emerged as monophyletic groups in molecular phylogenetic studies (Audzijonyte et al, 2012;Valdés et al, 2013). The first claim of the occurrence of large deep-water vesicomyids in the Mediterranean Miocene was based on the discovery in 1992 (Taviani et al, 1992;Taviani, 1996) of a bed containing 'Calyptogena' (= Archivesica) associated with turbidites in the Romagna Apennines (for details see Berti et al, 1994;Taviani, 2014). However, large vesicomyids such as those reported here are not rare in some well-studied outcrops and their occurrence could not have escaped the attention of former investigators.…”

“…This view changed after the first discovery of faunal communities at methane seeps in the deep Gulf of Mexico with similarly large bivalves (Paull et al, 1984) and the recognition that methane seep carbonates can be identified based on their distinctive, light carbon isotope signature (Hovland et al, 1987). The 'Calcari a Lucina' deposits throughout Italy are now considered as ancient deep-water methane seep deposits Conti et al, 1993;Terzi, 1993;Aharon and Sen Gupta, 1994;Berti et al, 1994;Ricci Lucchi and Vai, 1994;Taviani, 1994;Terzi et al, 1994;Peckmann et al, 1999;Clari et al, 2004b;Conti et al, 2004. Despite this wealth of geologic literature on these deposits, modern studies on the macrofauna are relatively rare (Moroni, 1966;Taviani, 1994Taviani, , 2011Taviani, , 2014Taviani et al, 2011).…”