Comment: 03:08 - 03:54 (00:46)
Source: Annenberg/CPB Resources - Earth Revealed - 4. The Sea Floor
Keywords: ocean, "volcanic eruption", erosion, salt, "carbon dioxide", chlorine, "sulfur dioxide", sodium, magnesium
Our transcription: We call our world "Planet Earth."
A more apt name might be "Planet Ocean" since the oceans cover more than 70 percent of the globe's surface.
This vast amount of water probably grew from the condensation of volcanic steam and from the melting of ice in comets which struck the primeval Earth.
From the beginning, the oceans have contained more than just water.
Carbon dioxide, chlorine, and sulfur dioxide, which are volcanic gases, dissolve easily in water.
Sodium, magnesium, and many other elements weathered from rocks on land continuously pour into the sea from the mouths of rivers.
These chemicals make oceans salty.
Geology School Keywords