EGU21-9955
https://doi.org/10.5194/egusphere-egu21-9955
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Field evidence for coal combustion links the 252 My-old Siberian Traps with global carbon disruption

Linda Elkins-Tanton1, Steven Grasby2, Benjamin Black3, Roman Veselovskiy4, Omid Ardakani2, and Fariborz Goodarzi5
Linda Elkins-Tanton et al.
  • 1Arizona State University, Interplanetary Initiative, Tempe, United States of America (ltelkins@asu.edu)
  • 2Geological Survey of Canada, 3303 33rd St NW Calgary Alberta Canada, T2L 2A7
  • 3Department of Earth and Atmospheric Science, City College of New York, 160 Convent Avenue, New York, NY 10031
  • 4Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia
  • 5FG & Partners Ltd., 219, Hawkside Mews, NW, Calgary, AB, T3G 3J4, Canada

The Permo-Triassic Extinction was the most severe in Earth history. The Siberian Traps eruptions are strongly implicated in the global atmospheric changes that likely drove the extinction. A sharp negative carbon isotope excursion coincides within geochronological uncertainty with the oldest dated rocks from the Norilsk section of the Siberian flood basalts. The source of this light carbon has been debated for decades.

We focused on the voluminous volcaniclastic rocks of the Siberian Traps, relatively unstudied as potential carriers of carbon-bearing gases. Over six field seasons we collected rocks from across the Siberian platform and show the first direct evidence that the earliest eruptions particularly in the southern part of the province burned large volumes of a combination of vegetation and coal. Samples from the Maymecha-Kotuy region, from the Nizhnyaya Tunguska, Podkamennaya Tunguska, and Angara Rivers all show evidence of high-temperature organic matter carbonization and combustion.

Field evidence indicates a process in which ascending magmas entrain xenoliths of coal and carbonaceous sediments that are carbonized in the subsurface and also combusted either through reduction of magmas or when exposed to the atmosphere. We demonstrate that the volume and composition of organic matter interactions with magmas may explain the global carbon isotope signal, and have significantly driven the extinction.

How to cite: Elkins-Tanton, L., Grasby, S., Black, B., Veselovskiy, R., Ardakani, O., and Goodarzi, F.: Field evidence for coal combustion links the 252 My-old Siberian Traps with global carbon disruption, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9955, https://doi.org/10.5194/egusphere-egu21-9955, 2021.