Unformatted text preview: on the sea floor. First, a `hot spot' existed on the ocean bed, which let out a plume of material called magma. This magma may originate as deep as 2,883km below the ocean bed. Next, further eruptions took place, which built up the volcano. Eventually, it emerged above the surface of the ocean. Since that time, the spume of magma has remained static as the Pacific tectonic plate moves in a north-west direction across it at a speed of 7-9cm per year. As it moves, a volcano forms as it passes over the hotspot and then become inactive when it has passed it. (164 words)...
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This note was uploaded on 10/23/2011 for the course IELTS 1101 taught by Professor We during the Spring '11 term at Sussex County Community College.
- Spring '11