Below is an interesting paper, with PDF files online,
about the role of contact metamorphism of evaporites
and organic rich strata by the Siberian Traps and
the end-Permian extinctions.
Svensen, H., Planke, S., Polozov, A.G., Schmidbauer, N.,
Corfu, F., Podladchikov, Y.Y. and Jamtveit, B., 2009.
Siberian gas venting and the end-Permian
environmental crisis. Earth and Planetary Science
Letters, 277(3-4), pp.490-500.
http://folk.uio.no/hensven/Svensen_EPSL_2009.pdf
https://henriksvensen.wordpress.com/publicationspapers/
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