Petter Silkoset

• Kulakov, Evgeniy; Torsvik, Trond Helge; Doubrovine, Pavel V.; Slagstad, Trond; Ganerød, Morgan & Silkoset, Petter [Show all 7 contributors for this article] (2021). Jurassic fast polar shift rejected by a new high-quality paleomagnetic pole from southwest Greenland. Gondwana Research. ISSN 1342-937X. 97, p. 240–262. doi: 10.1016/j.gr.2021.05.021. Full text in Research Archive
• Svensen, Henrik; Hammer, Øyvind; Chevallier, Luc; Jerram, Dougal Alexander; Silkoset, Petter & Polteau, Stephane [Show all 7 contributors for this article] (2020). Understanding thermogenic degassing in large igneous provinces: Inferences from the geological and statistical characteristics of breccia pipes in the western parts of the Karoo Basin. In Adatte, Thierry; Bond, David P.G. & Keller, Gerta (Ed.), Mass extinctions, volcanism, and impacts. The Geological Society of America. ISSN 9780813725444. p. 67–84.
• Andersen, Torgeir Bjørge; Austrheim, Håkon Olav; Deseta, Natalie; Silkoset, Petter & Ashwal, Lewis D. (2014). Large subduction earthquakes along the fossil Moho in Alpine Corsica. Geology. ISSN 0091-7613. 42(5), p. 395–398. doi: 10.1130/G35345.1. Show summary

  ABSTRACT Subduction earthquakes release vast amounts of energy to crust and mantle lithosphere. The products of such drastic events are rarely observed in the field because they are mostly lost by subduction. We present new observations of deformation products formed by a few very large and numerous small intermediate-depth Alpine subduction earthquakes that are pre- served along the exhumed gabbro–mantle peridotite contact of the Piemont-Liguria oceanic basin in Corsica. The abrupt release of energy resulted in shear heating events that completely melted both gabbro and peridotite. The large volumes of melt that were generated can be stud- ied in the fault and injection vein breccia complex along the fault zone. The energy required for wholesale melting of a large volume of peridotite along the fault combined with previous esti- mates of stress drops show that very large earthquakes took place along the Moho of the sub- ducting plate. Because these fault rocks formed by intraplate seismicity, we suggest, by analogy with present-day subduction, that they represent a proxy for the lower seismogenic zone.

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• Kulakov, Evgeniy; Doubrovine, Pavel V.; Torsvik, T.H; Werner, Stephanie C. & Silkoset, Petter (2018). Paleomagnetism of Late Jurassic – Early Cretaceous coast-parallel dykes in SW Greenland. Show summary

  It is a well-known and still unresolved problem of the Jurassic to Early Cretaceous apparent polar wander paths (APWP) discrepancy between those for North America (Laurentia) and Eurasia. Paleomagnetic poles derived from coeval rocks from the two continents differ significantly with North American poles characterized by shallower pole latitudes. The APWP mismatch cannot be resolved by correction for inclination shallowing or using different plate circuits. One of the possible explanations for the observed phenomenon is that paleomagnetic data from North America show the effects of younger remagnetizations and/or tectonic rotation. In an attempt to resolve this problem, paleomagnetic study of samples from ~35 Late Jurassic to Early Cretaceous coast-parallel mafic dykes exposed in SW Greenland (part of Laurentia) was carried out. Paleomagnetic samples have been subjected to a step-wise thermal and alternating field demagnetization techniques which yielded well-defined characteristic remanent components. A primary nature of the characteristic remanence is supported by positive baked-contact tests and the presence of paleomagnetic directions of both polarities that pass a reversal test. Our results indicate that the paleomagnetic pole for Greenland has higher latitude than the coeval North American poles and plots closer to the APW path for Eurasia. We will discuss the results and their implications for global Mesozoic apparent polar wander and paleogeography during Jurassic and early Cretaceous times.

• Planke, Sverre; Zuchuat, Valentin; Svensen, Henrik; Hammer, Øyvind; Braathen, Alvar & Silkoset, Petter [Show all 27 contributors for this article] (2016). Coring and High-Resolution Imaging of the Permian-Triassic Boundary in Deltadalen, Svalbard.
• Planke, Sverre; Twitchett, Richard; Zuchuat, Valentin; Svensen, Henrik; Hammer, Øyvind & Braathen, Alvar [Show all 22 contributors for this article] (2015). Coring the Permian-Triassic Boundary in Deltadalen, Svalbard.
• Silkoset, Petter; Svensen, Henrik & Planke, Sverre (2014). Breccia pipes in the Karoo Basin, South Africa, as conduits for metamorphic gases to the Early Jurassic atmosphere.
• Andersen, Torgeir Bjørge; Deseta, Natalie; Silkoset, Petter; Austrheim, Håkon Olav & Ashwal, Lewis D. (2014). Large Subduction Earthquakes along the fossil MOHO in Alpine Corsica: what was the role of fluids?
• Silkoset, Petter; Andersen, Torgeir Bjørge; Austrheim, Håkon Olav; Magraso, Anna & Wheeler, John (2013). Microstructure of ultramafic pseudotachylyte from Alpine Corsica – insights into earthquakes in mantle lithosphere.

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