Presentation on theme: "Field Geosciences Teaching Module: Geoparks and Geosites Geopark Naturtejo Meseta Meridional Fossil trees of Vila Velha de Ródão: How these fossils do."— Presentation transcript:
Field Geosciences Teaching Module: Geoparks and Geosites Geopark Naturtejo Meseta Meridional Fossil trees of Vila Velha de Ródão: How these fossils do enable to recognize climate changes?
Geological Map of Naturtejo Global Geopark Paleontological findings
The fossil trunks were found on the Monte do Pinhal terrace (T1) from Tejo river: It is the oldest (1,6 million years old) It has the highest position in relation with present riverbed (181m)
Fossil Trees of Vila Velha de Ródão in the Fossils Garden
Fossilization After the death of the tree it was buried and the cells composing the plant fibres were filled by silica coming from dissolved silicate sediments - Permineralization. Thousands of years
Silicified trunk Why do the trunks have such color?
The fossils are older or the same age as the sediments where they were found?
Age of the fossil trunks Natural polishing of the fossil Collision marks with pebbles Fossil trunks were transported as clasts among high energy river bed load and deposited in the river terrace Thus, fossil trunks are older than the fluvial terrace, with na estimated age between 15 to 5 million years old.
These trees share the features of the same tree attributed to Annonoxylon teixeirae, whose present best known representative is the Annona-Tree Where can you find Annona-trees in the wild forests nowdays? In which type of climate?
Present distribution of Annonaceans Hot and humid latitudes
Paleoenvironment of Naturtejo Geopark 15-5 million years ago Hot and in some periods more humid climate