Cerro Cuadrado Petrified ForestAround 160 million years ago in a temperate to subtropical zone of th
Cerro Cuadrado Petrified ForestAround 160 million years ago in a temperate to subtropical zone of the supercontinent Gondwana (then a supercontinent comprising South America, India, Australia, Antarctica, India and some other bits and pieces) that is now called southern Patagonia, a forest of hundred metre tall relatives of monkey puzzle trees was buried in volcanic ash. An entire forest ecosystem dating to the late Jurassic was partially preserved as the ash turned into rock, including many large pieces of Auracaria. The silica from the ash gradually replaced the original plant matter as it was dissolved and re precipitated by mineralised waters.Discovered in 1919 by German Argentinian botanist who followed up the fossil pine cones he encountered in local farms back to their source, the trees preserve some of the earliest evidence for bracket fungus and wood boring beetles. The cones came from a tree known as Auracaria mirabilis, and it is thought that the long necks of sauropod dinosaurs such as Argentinosaurus may have evolved specifically to browse on these huge tall trees. Here we have a rare piece showing a 6.5cm cone still attached to 8.5cm of the branch that once sprouted it, all sitting on a matrix of lithified ash. The eruption occurred during the season when the cones had just finished maturing.LozImage credit: LGF Foundationhttps://lgfmuseum.org/ -- source link
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