Geology, stratigraphy, and fossil vertebrates of Gotland, Sweden: a review
2016 (English)Licentiate thesis, comprehensive summary (Other academic)
The Silurian limestones of Gotland, Sweden, and their exceptionally well-preserved fossils have attracted the interest of scientists for more than 200 years. The sedimentary rocks represent approximately 10 million years of time, and were deposited in a shallow, equatorial inland sea named the Baltic Basin. The majority of the sediments are composed of reef-associated strata, but a general transition can be seen along the strike from shallow water in the northeast to deeper shelf environments in the southwest. The understanding of the stratigraphy and the geology of Gotland has greatly improved during the last decades. This research on Gotland has also led to the discovery of a series of stable isotope excursions and extinctions among several faunal groups. These events were probably linked to cycles in atmospheric and oceanic states, and three of them have been recognized globally. The Baltic Basin was also home to a variety of early vertebrates. The first fossil vertebrates from Gotland were reported in 1861, but the most extensive study of these early fishes was performed in the late 1900s. More recently it was shown that the vertebrates were also affected by one of the extinction events. This thesis is an extensive review of previous work and will form a geological basis for future studies. In this work, all previous reports of vertebrates have been gathered, reviewed, and the old samples have been placed in an updated stratigraphical framework. The scale taxonomy of Gotland vertebrates, including the Baltic acanthodians, has been evaluated and partly revised. Additionally, the depositional environments of the sampled areas have been investigated. Studying the vertebrates of Gotland is important for understanding the distribution of vertebrates through time and in different environments during the Silurian. Initial results indicate environmental preferences among vertebrates on both group and species-level, which may prove useful for testing the vertebrate biozonation developed for the Silurian.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2016. , 78 p.
Silurian, Gotland geology, Baltic Basin, extinction events, isotope excursions, atmospheric and oceanic cycles, early vertebrates, scale taxonomy, environmental preferences, vertebrate biozonation.
Other Earth and Related Environmental Sciences
Research subject Earth Science with specialization in Historical Geology and Palaeontology
IdentifiersURN: urn:nbn:se:uu:diva-281659OAI: oai:DiVA.org:uu-281659DiVA: diva2:915063
2016-04-27, EBC/9:2008, Norbyvägen 22, Uppsala, 10:15 (English)
Ebbestad, Jan Ove
Blom, HenningAhlberg, PerTiiu, Märss
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