Gardens of volcanoes in the Pacific.
The East Pacific Rise marks a great rift in Earth's outer shell. As tectonic plates on the sides of the rift slowly inch apart, molten rock rises to fill the gap, creating new pieces of ocean floor. Scheirer says the volcanoes discovered along the southern part of the rise are three times more numerous than those along a well-studied part of the rise north of the equator. What's more, sonar images reveal that these volcanoes are sprouting over a broader area than those in the north. Because most of the southern East Pacific Rise remains unmapped, scientists do not know whether other patches have such widespread volcanic activity. If so, that would indicate a fundamental difference in the way the northern and southern sections of the rise evolve.
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|Title Annotation:||mapping of East Pacific Rise seafloor reveals evidence of many volcanoes|
|Article Type:||Brief Article|
|Date:||Jun 5, 1993|
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