Endolithic bioerosion in cephalopods from the upper Carboniferous Buckhorn Asphalt Quarry Lagerstätte (Oklahoma, USA)

Beitrag bei einer Tagung


Details zur Publikation

Autorinnen und Autoren: Seuß B, Nützel A
Jahr der Veröffentlichung: 2017
Sprache: Englisch


Abstract

Deposits of
the Pennsylvanian (upper Carboniferous) Buckhorn Asphalt Quarry in southern
Oklahoma, USA, are of mixed siliciclastic-carbonatic composition;
however,crucial is the high content of hydrocarbons, that intruded the
sediments during or onlyshortly after deposition. These hydrocarbons impregnated
not only the deposits but more important, the fossils within. The result of
this intense soaking with hydrocarbons, that altered into asphalt afterwards,
was an upper Carboniferous (Pennsylvanian) Lagerstätte of outstanding quality;
e.g., preservation of delicate shell ornamentation and juvenile shells,
preservation of color patterns on naticopsids, as well as original shell
microstructure and mineralogy in different taxa (Bandel et al. 2002; Seuss et
al. 2009, 2012a, b; Ernst et al. 2016). In addition, the fauna is high diverse
with approximately 150 different taxa reported so far (Seuss et al. 2009). Many
shells show intense bioerosion on their surface and borings are also well
visible in thin sections. In an earlier study on the Buckhorn bioeroders Wisshak
et al. (2008) studied and interpreted the ichnocenosis present in Buckhorn
fossils. The study was mainly based on gastropod and bivalve shells and yielded
an assemblage of 18 known and one new ichnospecies. The ichnocoenosis was the
most diverse record of ichnotaxa of that age and contains 13 first, including
nine oldest, appearances for the Carboniferous (Wisshak et al. 2008, Table 2)
and it represents the shallow euphotic zone II–III following the
ichnobathymetric scheme of Glaub (1994) and Vogel et al. (1995).



Because the
first study focussed on shallow marine, benthic organisms (i.e., gastropods,
bivalves) a second study was performed recently to investigate shells ofnektonic
taxa that are more prone to transportation after death of the animal. These
are, for the study, orthoconic and coiled nautiloids and ammonoids
(goniatites). The shells derive from a coquina that represents the deepest
section of a cyclotheme that comprises the Buckhorn Asphalt Quarry’s deposits
(compare Seuss et al. 2009, Fig. 6). In total 32 remains of orthoconic and 28
remains of the shells of coiled nautiloids and ammonoids are included in this
analysis. Synthetic resin casts were prepared and preliminary results prove the
presence of 25-30 ichnotaxa. Compared to studies on recent Nautilus (Seuss et
al. 2015a, b, 2016) diversity is similar; however, the taxa differ distinctly.
In the Buckhorn cephalopods representatives of the cyanobacteria are most
diverse and most abundant, in orthoconic specimens, are the chlorophyte trace Ichnoreticulina
elegans and a new ichnospecies of Scolecia (produced by cyanobacterium?) while
in coiled cephalopods Flagrichnus profundus (produced by the fungus Schizochytrium
sp.) and for ms of ‘very thin’ / ‘super thin’ traces dominate the association
(rhodophyte / unknown heterotroph). A minimum of two ichnotaxa is  reported for the first time; this number might
be extended by so far unidentified traces of presumable foraminiferan origin. Despite
the high diversity of traces, no ichnocoenosis was identified that would help
in the identification of the relative bathymetry of the deposits and their
fossil remains.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Seuß, Barbara Dr.
Lehrstuhl für Paläoumwelt


Einrichtungen weiterer Autorinnen und Autoren

Ludwig-Maximilians-Universität (LMU)


Zitierweisen

APA:
Seuß, B., & Nützel, A. (2017). Endolithic bioerosion in cephalopods from the upper Carboniferous Buckhorn Asphalt Quarry Lagerstätte (Oklahoma, USA). In Proceedings of the 9th International Bioerosion Workshop. Rom, IT.

MLA:
Seuß, Barbara, and Alexander Nützel. "Endolithic bioerosion in cephalopods from the upper Carboniferous Buckhorn Asphalt Quarry Lagerstätte (Oklahoma, USA)." Proceedings of the 9th International Bioerosion Workshop, Rom 2017.

BibTeX: 

Zuletzt aktualisiert 2019-18-04 um 05:23