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Paläontologische Zeitschrift

, Volume 66, Issue 3–4, pp 405–413 | Cite as

Paleoecology of a low-diversity silurian community from the tofta beds of Gotland

  • Rodney Watkins, Milwaukee
Article

Abstract

The Silurian (Wenlockian) Tofta Beds at Galgberget 1, Gotland, Sweden, formed in a protected intertidal setting. Massive fenestral limestone at this locality contains a low diversity community dominated by stromatoporoids, calcareous algae, and ostracods, with less common rugose corals, bryozoans, brachiopods, and trilobites. Abundance of stromatoporoids, which form about 40% of sediment volume, suggests reef-like conditions. The Tofta community differs from typical Silurian reef communities, however, in its low diversity, very limited tiering, and absence of groups such as crionozoans and tabulates. These differences are possibly due to intertidal conditions which precluded upward growth of a mound structure and subjected the community to periodic desication.

Keywords

Wackestone Ostracode Stromatoporoids Oncolites Domical 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Kurzfassung

Die Tofta Beds des Wenlock bei Galgberget 1, Gotland (Schweden), bildeten sich in einem geschützten Intertidalbereich. Massive Kalke mit Fenstergefüge enthalten eine artenarme Fossilgemeinschaft, die von Stromatoporen, Kalkalgen und Ostracoden dominiert wird, während rugose Korallen, Bryozoen, Brachiopoden und Trilobiten weniger häufig sind. Die Häufigkeit der Stromatoporen, die etwa 40% des Sedimentvolumens ausmachen, legen riffähnliche Verhältnisse nahe. Die Tofta-Gemeinschaft unterscheidet sich jedoch von typischen Silur-Riffgemeinschaften durch ihre niedrige Diversität, ihre sehr geringe Stratifizierung und dadurch, daß Gruppen wie Crinozoen und tabulate Korallen fehlen. Die Unterschiede lassen sich möglicherweise auf die intertidalen Verhältnisse zurückführen, die ein Höhenwachstum der Gemeinschaft verhinderten und sie periodischer Austrocknung unterwarfen.

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Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 1992

Authors and Affiliations

  • Rodney Watkins, Milwaukee
    • 1
  1. 1.Geology DepartmentMilwaukee Public MuseumMilwaukeeUSA

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