Burial Diagenetic Overprinting of the Shuram CIE

Overview

The Shuram Carbon Isotope Excursion is one of the largest negative δ¹³C anomalies in Earth history, recorded globally in Ediacaran-age carbonate rocks, and its origin — whether it reflects a genuine seawater signal or later diagenetic alteration — remains contested. This project examines the excursion as recorded in the Windermere Supergroup of the Mackenzie Mountains, northwest Canada, and asks whether the primary isotope signal has been overprinted by two distinct generations of burial fluids passing through the rock after deposition. Resolving that history matters well beyond this one section: the Shuram excursion is a key global stratigraphic marker, and knowing how much of its signal is primary versus diagenetic is essential for interpreting what it says about Ediacaran ocean chemistry.

This is an active senior undergraduate thesis project at Penn State, led by Kayla Foster and co-advised with Dr. Kimberly V. Lau, Dr. Justin V. Strauss, and Dr. Rose L. Harding. A manuscript is currently in preparation, and preliminary results were presented at the Mid-Atlantic Geobiology Symposium.

Key Figure

Placeholder — swap in the stratigraphic column and δ¹³C profile once the manuscript figures are finalized.

Presentations

Foster, K., Lau, K.V., Strauss, J.V., Harding, R.L., McCormick, C.A. A Tale of Two Fluids: Burial Diagenetic Overprinting of the Shuram Carbon Isotope Excursion (Windermere Supergroup, Mackenzie Mountains, northwest Canada). Poster Presentation at: Mid-Atlantic Geobiology Symposium.

Foster, K., McCormick, C.A., Strauss, J.V., Lau, K.V. (In Prep). A Tale of Two Fluids: Burial Diagenetic Overprinting of the Shuram Carbon Isotope Excursion (Windermere Supergroup, Mackenzie Mountains, Canada). Undergraduate Thesis, The Pennsylvania State University.