Thursday, May 02, 2013

Fires During the Permian


The burning of Gondwana: Permian fires on the southern continent—A palaeobotanical approach

Authors:

1. André Jasper (a)
2. Margot Guerra-Sommer (b)
3. Abdalla M.B. Abu Hamad (c)
4. Marion Bamford (d)
5. Mary Elizabeth Cerruti Bernardes-de-Oliveira (e, f)
6. Rajni Tewari (g)
7. Dieter Uhl (h, i)

Affiliations:

a. Centro Universitário UNIVATES, Lajeado, Brazil

b. Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

c. The University of Jordan, Amman, Jordan

d. BPI Palaeontology, University of the Witwatersrand, Johannesburg, South Africa

e. Universidade de Guarulhos, Guarulhos, Brazil

f. Universidade de São Paulo, São Paulo, Brazil

g. Birbal Sahni Institute of Palaeobotany, Lucknow, India

h. Senckenberg Forschungsinstitut und Naturmuseum Frankfurt, Frankfurt am Main, Germany

i. Senckenberg Centre for Human Evolution and Palaeoenvironment, Eberhard Karls Universität Tübingen, Tübingen, Germany

Abstract:

Fossil charcoal has widely been accepted as a direct indicator for the occurrence of palaeo-wildfires. In Upper Palaeozoic sediments of Euramerica and Cathaysia, records of these remains are relatively common and (regionally and stratigraphically) more or less homogeneously distributed in terrestrial sequences. On the other hand, just a few records have been published for the Permian of Gondwana and only recently has it been demonstrated that macroscopic charcoals are also common here. Most Permian macroscopic charcoal from Gondwana is gymnospermous and has been reported from coal-bearing strata. Macroscopic charcoal occurrences are spread out in different sequences and also in distinct stratigraphic intervals in the Permian [e.g., Paraná Basin (Sakmarian/Artinskian of Brazil), Karoo Basin (Artinskian of South Africa), Damodar Basin (Lopingian of India) and Dead Sea area (Changhsingian of Jordan)]. They range from peri-glacial/post-glacial to warm temperate climatic systems throughout the Permian. Macro- and micro-charcoal occurrences are compared to inertinite incidences to support the pyrogenic origin for these coal macerals and to provide an up to date overview on the known evidences of Permian wildfires on Gondwana in space and time.

This has some serious implications for the paleoatmosphere:  you don't get fires if the oxygen level falls too low.  This goes from the Sakmarian to the Lopingian. 

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