Multiple phyla, one time resolution? Similar time averaging in benthic foraminifera, mollusk, echinoid, crustacean, and otolith fossil assemblages

Autor(en)
Rafał Nawrot, Michaela Berensmeier, Ivo Gallmetzer, Alexandra Haselmair, Adam Tomašových, Martin Zuschin
Abstrakt

Time averaging of fossil assemblages determines temporal precision of paleoecological and geochronological inferences. Taxonomic differences in intrinsic skeletal durability are expected to produce temporal mismatch between co-occurring species, but the importance of this effect is difficult to assess due to lack of direct estimates of time averaging for many higher taxa. Moreover, burial below the taphonomic active zone and early diagenetic processes may alleviate taxonomic differences in disintegration rates in subsurface sediments. We compared time averaging across five phyla of major carbonate producers co-occurring in a sediment core from the northern Adriatic Sea shelf. We dated individual bivalve shells, foraminiferal tests, tests and isolated plates of irregular and regular echinoids, crab claws, and fish otoliths. In spite of different skeletal architecture, mineralogy, and life habit, all taxa showed very similar time averaging varying from ~1800 to ~3600 yr (interquartile age ranges). Thus, remains of echinoids and crustaceans—two groups with multi-elemental skeletons assumed to have low preservation potential—can still undergo extensive age mixing comparable to that of the co-occurring mollusk shells. The median ages of taxa differed by as much as ~3700 yr, reflecting species-specific timing of seafloor colonization during the Holocene transgression. Our results are congruent with sequestration models invoking taphonomic processes that minimize durability differences among taxa. These processes together with temporal variability in skeletal production can overrule the effects of durability in determining temporal resolution of multi-taxic fossil assemblages.

Organisation(en)
Institut für Paläontologie
Externe Organisation(en)
Slovak Academy of Sciences (SAS)
Journal
Geology
Band
50
Seiten
902-906
Anzahl der Seiten
5
ISSN
0091-7613
DOI
https://doi.org/10.1130/G49970.1
Publikationsdatum
08-2022
Peer-reviewed
Ja
ÖFOS 2012
105118 Paläontologie
Schlagwörter
ASJC Scopus Sachgebiete
Geology
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/multiple-phyla-one-time-resolution-similar-time-averaging-in-benthic-foraminifera-mollusk-echinoid-crustacean-and-otolith-fossil-assemblages(fcfed6b6-724e-4970-957e-2beee9385b3d).html