Volcanic island

The ocean floor

A submarine volcano becomes an island when its summit rises above sea level. Waves erode the exposed rock while eruptions may add new lava; some island chains trace the motion of a plate over a hotspot.

html,body{position:static!important;height:auto!important;overflow:auto!important}body{color:#e8f1ff}body>:not(noscript){display:none!important}#static-seo-content img{display:block;max-width:100%;height:auto}#static-seo-content{max-width:800px;margin:40px auto;padding:24px;font:16px/1.7 Arial,sans-serif}#static-seo-content a{color:#a8d5ef}#static-seo-content nav{display:flex;flex-wrap:wrap;gap:12px} A yellow submersible explores an ocean trench between steep rocky walls at a depth of 8 km.

A yellow submersible explores an ocean trench between steep rocky walls at a depth of 8 km.

Volcanic island

A submarine volcano becomes an island when its summit rises above sea level. Waves erode the exposed rock while eruptions may add new lava; some island chains trace the motion of a plate over a hotspot.

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