Central Skåne Volcanic Province
The Central Skåne Volcanic Province was a site of volcanic activity in the Scania region of Sweden during the Mesozoic Era of the Earth's geological history. The volcanism began with a first and main phase in late Sinemurian to Toarcian times around 191 to 178 Ma. Then volcanism continued sporadically for another 80 million years.[1] More than one hundred volcanic necks of basaltic composition exist in Scania evidencing this volcanism. In central Scania, volcanism was in the form of a volcanic field of cinder cones that had Strombolian eruption styles.[2] These cones produced tuffite deposits made largely of lapilli with rare volcanic bombs.[2][3] Pyroclastic materials were subsequently palagonitized or largely altered to clay minerals.[2] While eruptions occurred on land the sea was likely very close to the area.[2][3] Besides purely pyroclastic sediments, lahar deposits have also been identified around the remnants of the volcanoes.[4]
Beneath a lahar deposit at Korsaröd (Djupadal Formation), Early Jurassic plant fossils including wood, pollen and spores have been exceptionally well preserved.[5] The degree of preservation is such that cell-scale features like organelles and chromosomes have been identified in the fossils. At this location plants grew in a substrate with extensive hydrothermal alteration.[4]
The volcanism is possibly the result of decompression melting of the lithospheric mantle beneath.[1] The volcanism is linked to a rift flank fault along the Sorgenfrei–Tornquist Zone, which is a failed rift associated with extension in the North Sea and the opening of the North Atlantic.[1][2][4] The background to the volcanism is the break-up of Pangea, and thus it is analogous to the much more voluminous Karoo-Ferrar flood basalts of Southern Africa.[1]
See also
[edit]- List of flood basalt provinces
- Central Atlantic magmatic province, Late Triassic to Early Jurassic igneous province in the area
- Skagerrak-Centered Large Igneous Province, Late Carboniferous to Early Permian igneous province in Denmark and southern Sweden
- Osmunda regalis
References
[edit]- ^ a b c d Bergelin, Ingemar (2009). "Jurassic volcanism in Skåne, southern Sweden, and its relation to coeval regional and global events". GFF. 131 (1–2): 165–175. doi:10.1080/11035890902851278.
- ^ a b c d e Augustsson, Carita (2001). "Lapilli tuff as evidence of Early Jurassic Strombolian-type volcanism in Scania, southern Sweden". GFF. 123 (1): 23–28. doi:10.1080/11035890101231023. S2CID 140544085.
- ^ a b Ahlberg, Anders; Sivhed, Ulf; Erlström, Mikael (2003). "The Jurassic of Skåne, southern Sweden". Geological Survey of Denmark and Greenland Bulletin. 1: 527–541. doi:10.34194/geusb.v1.4682.
- ^ a b c Vajda, Vivi; Linderson, Hans; McLoughlin, Stephen (2016). "Disrupted vegetation as a response to Jurassic volcanism in southern Sweden". In Kear, B.P.; Lindgren, J.; Hurum, J.H.; Milàn, J.; Vajda, V. (eds.). Mesozoic Biotas of Scandinavia and its Arctic Territories. Geological Society, London, Special Publications. Vol. 434. pp. 127–147.
- ^ Bomfleur, Benjamin; McLoughlin, Stephen; Vajda, Vivi (2014). "Fossilized Nuclei and Chromosomes Reveal 180 Million Years of Genomic Stasis in Royal Ferns". Science. 343 (6177): 1376–1377. doi:10.1126/science.1249884. PMID 24653037. S2CID 38248823.