Fresh water and marine snails from 55 million years ago – #365papers – 2017 – 39

#365papers for February 8, 2017

Schmitz and Andreasson, 2001, Air humidity and lake δ¹⁸O during the latest Paleocene-earliest Eocene in France from recent and fossil fresh-water and marine gastropod δ¹⁸O, δ¹³C, and ⁸⁷Sr/⁸⁶Sr: Geological Society of America Bulletin, v. 113, p. 774-789.

What’s it about?

This paper describes oxygen isotope ratios from modern freshwater snails and how the values and patterns of intra-shell analyses relate to the overall climate of a region. These patterns are then compared with Paleocene-Eocene aged gastropods to get at ancient climate. Some marine snails were also studied to see how they compare with freshwater snails. Strontium was also used to help get at the amount and timing of precipitation and weathering  in a region.

Why does it matter?

One way we make interpretations of what ancient climates were like is through the use of geochemical markers like oxygen isotopes. This paper provides support that what we think we’re measuring is actually what we’re measuring.

Why did I read this?

I read this paper for this first time in 2007, when I started working with some clam shells from the Paleocene-Eocene boundary. I’m re-reading it now because I’m involved in a project with modern land snails and I’m revisiting the Paleocene-Eocene project as well.