The Lower Liassic Flora of Bayreuth

In the region of Bayreuth (Franken, Germany) the layers of the Lower Liassic are very well exposed. Till recently these sediments were called the Rhät-Liassic layers, in which the Rhät is the uppermost formation of the Triassic and the Liassic the lowermost formation of the Jurassic. However, it has been proved now that the Rhät does not occur in the neighbourhood of Bayreuth and that the sediments are of Lower Liassic age. The layers are also called Plant sandstone. The age of the strata is roughly 200 million years.

The spots on the map indicate a couple of sites, which have yielded plant fossils in the course of time. There has been intensive collecting in this area for many years, especially in the sand quarries. Most of the sites, however, are not productive any more and besides the situation is changing frequently. According to German law the quarries must be filled up when they are finished. The dotted areas in the map indicate the Lower Liassic.
In most cases the plants have been embedded in creeks being part of a fluvial system. Plants falling in turbulent water had hardly a chance to fossilize, but in quiet waters and in still creeks the situation was more favourable. That's why the fossils are found mostly in lenses. In fact these are transverse sections of petrified creeks.
The (rather soft) rock containing the fossils is mostly whitisch, yellowish or ochre coloured, but sometimes bands with reddish or black brown tints also occur. From time to time rapid sand sedimentations have taken place, covering the creeks, plant remains inclusive. River banks, stagnant river bends and lakes have also been preserved in some cases. But the plant layers are always very local. 

Collecting No fossil sites are described here, because I don't want to be responsible for the coming of too many collectors to the quarries. At the moment quarry owners sometimes give permission to collect, but it will be clear that this will change if the concourse is too large. Especially if some of the collectors will enter the quarry illegally. To diminish the enthousiasm a bit more, I can say (and this is really true) that the lenses with fossils are difficult to find and that the fossils (with some exceptions) are not spectacular because they have often the same colour as the rock. The clarity of the photos is for a large part the merit of the contrast function in my photo editing program.

Description of the flora
Below is the list of the collected plants. Click on the name of a group to go to the descriptions of the species.

Spiropteris

Click here to see a complete survey of the fossil photos.