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In the mid-twentieth century and corroborated ever since, researchers dredging the seafloor could not find any materials older than 180 million years.
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What do you understand by seafloor ?</h3>
The surface of an ocean or sea: seafloor According to this theory, the Earth's crust is divided into a number of enormous plates that together form the continents and ocean floors and are supported by a warm, plastic "mantle" beneath the surface. Mr. Walter Sullivan
Deposits of common minerals like copper, zinc, nickel, gold, silver, and phosphorus can be found on the seafloor. These deposits are nodules on silt from the abyssal plain that are typically 3 to 10 centimeters (1 to 4 inches) in diameter and appear as crusts on volcanic and other rocks.
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Tectonic plates
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The Gulf of Mexico and the Atlantic Ocean
