Volcanic Islands Most volcanic activity occurs along tectonic plate boundaries because that is where the lithosphere is weakest Within the Earth's mantle there are thin vertical plumes of hot magma, probably rising from the core, which remain fixed in position as the tectonic plates move overhead. These plumes create hot spots in the lithosphere above, where volcanic activity occurs. The site of such volcanism moves as the plates move. the volcanic islands in the chain get progressively older with distance from the island of Hawaii
Hawaii is a hotspot for volcanoes on the Pacific Plate that drifts North
Hotspots The eight main Hawaiian islands comprise the tops of one or more shield volcanoes The largest island, Hawaii, is formed from five volcanoes The shield volcanoes are very large structures, which can be up to many tens of kilometers in diameter Shield volcanoes often have more than one vent, as well as fissures along their sides. The Hawaiian Islands are a complex of shield volcanoes rising from the ocean floor The volcanic islands in the chain get progressively older with distance from the island of Hawaii
Kilauea, the world's most active volcanic crater is in the south of the central Hawaii Island
Kalapana The small town of Kalapana was once a treasured Hawaiian fishing village It was also the site of one of the largest and nicest black sand beaches. But in 1990, Madame Pele (Kilauea) changed the landscape of Hawaii dramatically. From April through December of that year, lava flowed relentlessly, burying the town and the Royal Garden Subdivision under 10 meters of molten rock.
Kalapana The slow moving lava engulfed homes, parks and roads. Almost everything in its path was completely destroyed. However, a few homes survived the devastation by sheer "luck". For some reason, the lava would part or turn and spare a single structure
The pictures from this presentation are from: Geogonline.org.uk Hawaiiweb Google.co.uk