The Paleocene-Eocene boundary in deep ocean foraminifera – #365papers – 2017 – 65

#365papers for March 6, 2017

Thomas and Shackleton, 1996, The Paleocene-Eocene benthic forminiferal extinction and stable isotope anomalies, in Knox, Corfield, Dunay, eds., Correlation of the Early Paleogene in Northwest Europe: Geological Society Special Publication n. 101, p. 401-441.

What’s it about?

This paper examines the abundance and geochemistry of single-celled organisms called foraminiferans (forams) that were living in the oceans around 55 million years ago. Forams are still present today worldwide. They make little tiny calcite skeletons (called tests) that can be used to identify the species and then can be analyzed.

Using these foram skeletons, the authors identified the many species that lived in the ocean before and after the Paleocene-Eocene boundary and recognized some extinctions associated with the boundary. With geochemical analysis, they showed that there are some significant anomalies (rapid, unexpected changes) at the Paleocene-Eocene boundary.

Why does it matter?

Counting numbers of individuals of a given species helps us recognize when and where extinction events happen. Adding geochemistry makes it possible to examine potential underlying causes of extinction.

Why did I read this?

I do a lot of research on the Paleocene-Eocene boundary (55 million years ago). But really, I opened this one searching for data from the middle Eocene (around 40 million years ago). I found some…