Turritelline mass accumulations from the Lower Miocene of southern Germany: implications for tidal currents and nutrient transport within the North Alpine Foreland Basin

Abstract

The mass occurrence of turritelline gastropod shells from the Lower Miocene of southern Germany allows for detailed studies of their palaeoecology, transport mechanisms, preservation potentials and the reconstruction of nutrient regimes. Changes in the fabric of the gastropod‐dominated beds are used to reconstruct a generally deepening environment corresponding to the Lower Miocene transgression within the Upper Molasse Sea of the North Alpine Foreland Basin. The sedimentary succession ranges from chaotically arranged, densely packed and near‐shore transported; wave‐influenced deposits showing bimodal shell orientations; more widely dispersed shells showing a uni‐directional orientation; and dispersed shells showing diverse orientations. The shells often show damage to the apex and aperture though it is not clear whether this is due to predation events, pagurisation or abrasion due to transport. An outstanding feature is the replacement of aragonite shells by calcite leading to internal vugs as well as modulating the outer shell surface morphology. The high density of turritelline gastropods indicates a nutrient‐rich palaeoenvironment at the northern edge of the Molasse Sea.

Paleoecology of naticid–molluscan prey interaction during the Late Jurassic (Oxfordian) in Kutch, India: evolutionary implications

“…Moreover, turritellines provide ethological responses (behavioral and nonshell characters) rather than morphological adaptation against the naticid drilling (for details, see Vermeij et al, 1980; Vermeij, 1982; Allmon, 1988; Allmon et al, 1990). In addition, the high mortality, especially of young individuals, is amply compensated by the high fecundity rate (“predator saturation by very large populations” of Allmon, 1988, p. 267; “mass occurrences of turritelline gastropods” of Nebelsick et al, 2020, p. 282). For these reasons, turritellines are one of the few marine gastropods that monopolized and dominated other molluscan fossil communities through ages (Price et al, 1985; Cohen, 1989; Geary and Allmon, 1990; Waite et al, 2008; Waite and Strasser, 2011) and are aptly termed as TDAs by Allmon (2007).…”

Trophic relationships in the Early Miocene Upper Marine Molasse of Baden-Württemberg, Southwest Germany, with special emphasis on the elasmobranch fauna

“…Ermingen is famous for the so-called "Erminger Turritellenplatte", a mass accumulation of gastropod shells belonging to the genus Turritella Lamarck, 1799 (Baier, 2008;Höltke, 2009;Nebelsick et al, 2019). A succession of 3.5 m of the Turritellenplatte was excavated in 2005 by a team from the Staatliches Museum für Naturkunde Stuttgart (SMNS; Stuttgart, Germany).…”

“…A succession of 3.5 m of the Turritellenplatte was excavated in 2005 by a team from the Staatliches Museum für Naturkunde Stuttgart (SMNS; Stuttgart, Germany). The Turritella shells are firmly cemented within bioclastic, coarse grained-sandstone with a calcareous matrix that can pass into a quartz-rich limestones (Nebelsick et al, 2019). According to Nebelsick et al (2019), silty marls with sands are also present, containing isolated specimens of Turritella and bivalves (Veneridae).…”

“…Other macrofossils are also often poorly preserved. This may be the reason for the scant recent literature about OMM macrofossils in Baden-Württemberg (Barthelt et al, 1991;Pfeil, 1991;Baier et al, 2004;Höltke, 2009;Nebelsick et al, 2019;Höltke et al, 2020;Feichtinger and Pollerspöck, 2021;Höltke et al, 2022; see also the informative outreach website by Feichtinger et al, 2022).…”

Taphonomic significance of Aristotle's 'Wheel Paradox': an example with the cerithid gastropod Cerithium atratum (Born, 1778) from Conceição Lagoon, Santa Catarina State, Southern Brazil

“…Empty shells of invertebrates behave as sedimentary particles and are subject to physical taphonomic modifications (biostratinomic) through different mechanisms controlled mainly by environmental conditions (e.g., type of substrate, hydraulic regime) that incorporate the skeletal remains into the sedimentary record; therefore the recognition of features left by those processes can aid in the reconstruction of ancient depositional environments (Müller, 1979;Dodd & Stanton, 1981;Kidwell & Bosence, 1991). Different observations and experiments have focused on the recognition of hydrodynamic effects on the orientation, movement, transportation and abrasion of modern shells as a way of identifying paleocurrents and understanding conditions that resulted in the formation of fossil assemblages (Ruedemann, 1897;Menard & Boucot, 1951;Krinsley, 1960;Potter & Pettijohn, 1963;Keeling & Williams, 1967;Nagle, 1967;Brenchley & Newall, 1970;Cataldo et al, 2013;Fick et al, 2018;Nebelsick et al, 2019). Studies addressing post-mortem physical modifications controlled by hydrodynamic regimes have shown that abrasion is the primary taphonomic process responsible for shell destruction in littoral environments (Tauber, 1942;Chave, 1960Chave, , 1964Driscoll, 1967Driscoll, , 1970Driscoll & Weltin, 1973;Milliman, 1974;Dodd & Stanton, 1981;Davies et al, 1989).…”