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eruption. There have been no catastrophic eruptions from land fissures in recorded history. But fissure eruptions have in the past been immense. They also make up
some of the world’s best known landforms, including The Giant’s Causeway in Northern Ireland and Fingal’s Cave
in Scotland. But far bigger than most people can imagine are the flood basalts that make up great areas of the Argentinian pampas and the majority of the Columbia- Snake basin in the northwestern United States. And biggest of all are the Deccan Traps, making up a landscape of basalt that covers about a sixth of the Indian subcontinent.
Hawaiian type
The Hawaiian chain of volcanic islands has given its name to the type of eruption that produces outpourings of basaltic lava from a single short fissure and therefore builds a broad, gently sloping cone. Many of these eruptions are associated with hot spots rather than with places where the crust is separating.
The hawaiian type of eruption produces frequent short bursts of lava that form lava fountains. They act as the sources for rivers of lava that run across the landscape as individual tongues rather than as sheets. Many rivers
(Below) Basalt can readily flood out of fissures and cascade across the landscape.
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