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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/ https://henriksvensen.wordpress.com/page/2/ Some related papers are: Burgess, S.D., Muirhead, J.D. and Bowring, S.A., 2017. Initial pulse of Siberian Traps sills as the trigger of the end-Permian mass extinction. Nature Communications, 8(1), p.164. https://www.researchgate.net/publication/318793382_Initial_pulse_of_Siberian_Traps_sills_as_the_trigger_of_the_end-Permian_mass_extinction https://www.researchgate.net/profile/Muirhead_D https://dspace.mit.edu/bitstream/handle/1721.1/113600/s41467-017-00083-9.pdf?sequence=1&isAllowed=y Polozov, A.G., Svensen, H.H., Planke, S., Grishina, S.N., Fristad, K.E. and Jerram, D.A., 2016. The basalt pipes of the Tunguska Basin (Siberia, Russia): High temperature processes and volatile degassing into the end-Permian atmosphere. Palaeogeography, Palaeoclimatology, Palaeoecology, 441, pp.51-64. Svensen, H.H., Frolov, S., Akhmanov, G.G., Polozov, A.G., Jerram, D.A., Shiganova, O.V., Melnikov, N.V., Iyer, K. and Planke, S., 2018. Sills and gas generation in the Siberian Traps. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 376(2130), p.20170080. https://www.researchgate.net/publication/327404155_Sills_and_gas_generation_in_the_Siberian_Traps https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127383/ https://www.semanticscholar.org/paper/Sills-and-gas-generation-in-the-Siberian-Traps.-Svensen-Frolov/6d0e86fcd2beea7d96c4e15240e50650c2ac235a Rampino, M.R., Rodriguez, S., Baransky, E. and Cai, Y., 2017. Global nickel anomaly links Siberian Traps eruptions and the latest Permian mass extinction. Scientific reports, 7(1), p.12416. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622041/ http://www.indiaenvironmentportal.org.in/files/file/Siberian trap eruptions.pdf Yours, Paul H.

Hey guys. In NZ we have quite a few volcanoes, and luckily for me living in christchurch, the most recent eruption in the south island was about 20 mya. On the "vanished world" trail, there is a preserved basaltic volcanic dyke/sill that has been injected into the strata beneath an ancient lagoon. While I'm aware that these magmatic intrusions don't break the surface, there is a broad fossil horizon not far from the top most termination of the sill, with beautiful small spirulla (?) (Some kind of elongate fossil snail) preserved in the rock. I was wondering, that as I mentioned before that this fossil horizon is not too far from the intrusion, just how much heat or mineral replacement does it take for igneous rocks the the associated hydrothermal minerals to completely destroy/deform/disfigure fossils in these kinds of geologic environments? I have included a rough sketch. Like all great geologic exposures, it occurs at a public road cutting, to provide context.