These movements in turn, produced balancing movements, fractures, folds, landslides, and the ascension and descension of ancient crystal blocks, forming the hills that today surround the region and the most recent layers of sediments.
Wind and water have eroded the sedimentary rocks in the Valley of the Moon.Sedimentary rock is one of the three main rock groups (along with igneous and metamorphic rocks) and is formed in four main ways: by the deposition of the weathered remains of other rocks (known as 'clastic' sedimentary rocks); by the accumulation and the consolidation of sediments; by the deposition of the results of biogenic activity; and by precipitation from solution.
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The Valley of the Moon in Prehistory.Since the large reptiles had already disappeared in the Holocene era, some 10,000 to 12,000 years ago, the valley was populated by pumas, guanacos, Creole hares, and a new type of animal--the birds.
Descendants of the dinosaurs-the most spectacular birds of this valley are the condors and the South American ostrich. On the contrary, of the ‘true reptiles’, only the small lizards and some poisonous snakes (the coral and yarara) remain.