Biologically agglutinated eukaryotic microfossil from Cryogenian cap carbonates

Area of Science:

• Paleobiology
• Geochemistry
• Sedimentology

Background:

• Cryogenian cap carbonates formed during post-glacial transgressions after the Sturtian glaciation.
• Microfossils in these carbonates offer insights into early life and environmental conditions.

Purpose of the Study:

• Describe and analyze microfossils from Cryogenian cap carbonates in Zambia and Mongolia.
• Compare these microfossils with previously studied ones from Namibia.
• Investigate the formation and preservation processes of these ancient microfossil assemblages.

Main Methods:

• Microfossil description and characterization (size, shape, wall thickness).
• Chemical and mineralogical analysis of microfossil walls and surrounding sediments.
• Comparative analysis across three different geological formations.

Main Results:

• Microfossils possess walls (10 ± 1 μm thick) of carbonaceous matter and aluminosilicate minerals.
• Mineralogy of microfossil walls matches the clay fraction of surrounding sediments.
• Evidence suggests primary biological agglutination of minerals by eukaryotes.

Conclusions:

• Agglutinating eukaryotes were widespread in marine environments post-Sturtian glaciation.
• These organisms thrived in carbonate-dominated settings.
• The findings expand our understanding of Cryogenian paleobiology and paleoenvironments.