Some charophytes from the middle dinosaur member of the Tendaguru formation (Upper Jurassic of Tanzania)
Biostratigraphy and paleoecology of the famous dinosaur beds of Tendaguru Formation, Tanzania, East Africa are still under discussion. Calcareous microfossils have not yet contributed to this question. Four samples from the Middle Dinosaur Member have now yielded charophyte gyrogonites of the specie...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
1999-01-01
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| Series: | Fossil Record |
| Online Access: | http://www.foss-rec.net/2/201/1999/fr-2-201-1999.pdf |
| Summary: | Biostratigraphy and paleoecology of the famous dinosaur beds of Tendaguru Formation, Tanzania, East Africa are still under discussion. Calcareous microfossils have not yet contributed to this question. Four samples from the Middle Dinosaur Member have now yielded charophyte gyrogonites of the species <i>Aclistochara</i> cf. <i>bransonii, Aclistochara</i> cf. <i>minor, Mesochara canellata</i>, and <i>Mesochara harrisi</i>. Considering ammonite datations in under- and overlying members, even their long stratigrapical ranges point to a Kimmeridgian age for the Middle Dinosaur Member of Tendaguru Formation. Salinity tolerances of the species (if autochthonous) suggest a variable environment with partly brackish, partly freshwater influences.
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Biostratigraphie und Paläoökologie der berühmten Dinosaurier-Fundschichten am Tendaguru Hill in Tansania (Ostafrika) sind bis heute umstritten. Kalkige Mikrofossilien hatten zu dieser Diskussion bisher nicht beigetragen. In vier Proben aus dem Mittleren Dinosauriermergel fanden sich nun Charophyten-Gyrogonite der Arten <i>Aclistochara</i> cf. <i>bransonii, Aclistochara</i> cf. <i>minor, Mesochara canellata</i> und <i>Mesochara harrisi</i>. Trotz generell langer stratigraphischer Reichweiten dieser Arten macht ihr Vorkommen im Zusammenhang mit Ammonitenfunden in unter- und überlagernden Schichten ein Kimmeridgium-Alter des Mittleren Dinosauriermergels wahrscheinlich, während ihre Salinitätstoleranzen (autochthones Vorkommen vorausgesetzt) auf ein wechselhaftes Milieu mit teils schwach brackischen, teils Süßwassereinflüssen hindeuten.
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doi:<a href="http://dx.doi.org/10.1002/mmng.1999.4860020115" target="_blank">10.1002/mmng.1999.4860020115</a> |
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| ISSN: | 2193-0066 2193-0074 |