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Evolution of Amazon Basin. Stage 1. 500 Million Years Ago Gondwanaland splits into South America and Africa Pre-Cambrian rocks erode and material is transported by rivers where they were compressed into sandstone
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Stage 1 • 500 Million Years Ago • Gondwanaland splits into South America and Africa • Pre-Cambrian rocks erode and material is transported by rivers where they were compressed into sandstone • Inland lake forms which drains into the Pacific creating a build up of sediment at the Delta
Stage 2 • 90 Million Years Ago • South America moves West away from Africa running into the Nazca Plate • Nazca Plate subducted and forces sedimentary material deposited in Delta to rise • Creates fold mountains (Andes) • North and East buckle to create a basin
Stage 3 • 10 Million Years Ago • Amazon River changes directions and flows towards the Atlantic • Volcanoes and magma aid in building up the Andes
Stage 4 • 2 Million Years Ago • Ice Age • Carves of sedimentary rock • Much of the eroded material is washed down into the basin formed by the North and East buckling
Stage 5 • Present • Tributaries bring sediment to the Amazon Basin • Upper regions of Andes erosion creates fast flowing river • Creates deep V-shaped valleys • Amazon Basin develops large flood plains due to seasonal flooding • Meandering occurs due to flat relief