Where: Michigan (46.5° N, 87.6° W: paleocoordinates 0.0° N, 0.0° E)

• coordinate estimated from map

When: Negaunee Formation, Orosirian (2050.0 - 1800.0 Ma)

• early Proterozoic; "Negaunee IF". Thought to be 2.1 Ga based on Sm-Nd dating, but U-Pb dating of a rhyolite in the correlative Hemlock Formation yielded an age of 1874 +/- 9 Ma (Schneider et al., 2002). The unit is likely also correlative to the Gunflint Chert, dated at 1878 +/- 1.3 Ma (Schneider et al., 2002).

Environment/lithology: marine; ironstone

Size classes: mesofossils, microfossils

Preservation: adpression

Primary reference: T.-M. Han and B. Runnegar. 1992. Megascopic Eukaryotic Algae from the 2.1-Billion-Year-Old Negaunee Iron-Formation, Michigan. Science 257(5067):232-235 [M. Uhen/M. Uhen/P. Wagner]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 192010: authorized by Mark Uhen, entered by Mark Uhen on 28.02.2018

Creative Commons license: CC BY (attribution)