This is a fossilized (or petrified tree) that lived during the Middle (+-275 Ma) to Late (+-255 Ma) Permian Period. Today's vegetation is completely different to the previous mentioned time. There were no grasses or flowering plants. The dominant plant types were the glossopterids in this time frame (the fossils of which are found in all the countries that were once part of thw Supercontinent Gondwana).
How did it form?
The tree trunk was buried during rapid burial with mineral-rich waters during a possible flood. Minerals (mostly silicate and quartz) that were dissolved in the surrounding waters, slowly replaced the organic material of the tree. The replacement process followed the original pattern of the tree's structure, yielding a very detailed mineralised replica of the tree trunk (see picture below).
The microstructures of the individual cells walls, tissues and growth rings, as well as stomata, can be seen under a microscope.
The morphology of the cells allows us to identify the wood, as well as to determine the environment which the tree lived in. Fossil trees of the Glossopteris group are abundant in the Senekal District, Free State, where this tree trunk was found during an Environmental Impact Assessment (EIA), conducted in an area intended for building construction. The well-preserved fossil was recovered and donated to the National Museum.
To log this Earth cache, please answer the following:
1. How long was the original fossil when found?
2. What is the estimated age of the tree?
3. From where did this tree originate?
4. Looking at the information plate, in how many continents (count only the named ones) are the Glossopteris remains found in?
Optional - Take a picture of yourself with the tree visible in the photo.
Email answers to the cache owner to qualify your find. Opening hours of the National Museum
Times open:
Monday: 08:00AM - 17:00 PM
Tuesday: 08:00AM - 17:00 PM
Wednesday: 08:00 AM - 17:00 PM
Thursday: 08:00 AM - 17:00 PM
Friday: 08:00 AM - 17:00 PM
Saturday: 10:00 AM - 16:00 PM
Sunday: 13:00 PM- 17:00 PM
Closed on Christmas Day and Good Friday.
Sources
>http://www.sahra.org.za/sahris/sites/default/files/heritagereports/1207%20Senekal%20HIA%20%28Phase%201%29%20Cobus%20Dreyer.pdf
>Oliewenhuis Art Museum Facebook page: https://m.facebook.com/OliewenhuisArtMuseum