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To help grow your subscriber list, the pop-up form is set to single opt-in by default.If you prefer, you can make your form double opt-in at anytime.Eruptions may produce tsunamis and floods and may trigger earthquakes. Volcanoes which have had no eruptions during historic times, but may still show fairly fresh signs of activity and have been active in geologically recent times are said to be dormant.There are also volcanoes which were formerly active but are of declining activity a few of which may be emitting only steam and other gases.
Other volcanic areas are the island of West Indies, those of the West coast of Africa, the Mediterranean region and Iceland.Geysers are hot springs from which water is expelled vigorously at intervals and are characteristics of regions of declining volcanic activity.Geysers are situated in Iceland, the Yellowstone park in USA and in New Zealand. The very high peaks in the Andes, in the Cascade Range of the Western United States, Mt. The loud rumblings are due to explosive movement of gases and molten rock which are held under very high pressure.
The volcanoes of the Hawaiian Islands are nearly 4300 metres above sea level since they are built over the floor of the Pacific ocean which at the site is 4300 to 5500 metres deep, the total height of the volcano may be about 9000 m or more. The eruption of a volcano is generally preceded by earthquakes and by loud rumblings like thunder which may continue on a very high scale during the eruption.Some volcanoes erupt for just a few minutes while some volcanoes spew their products for a decade or more. effusive and explosive eruptions, there are many subdivisions like, eruption of gases mixed with gritty pulverised rock forming tall dark ash clouds seen for many kilometres, flank fissure eruptions with lava oozing from long horizontal cracks on the side of a volcano.