VOLCANISM (Basic Terms (
Used to describe all forms of igneous…
Thermal spring/hot spring
A continuous flow of hot water from the ground.
It is usually (not always) associated with present or former volcanic activity.
They are non explosive and have dissolved minerals.
Hot springs are more common than geysers.
It is a hot spring that intermittently, sometimes at regular intervals, throws up a jet off hot water, steam, etc.
It may occur in area that are/were volcanic.
Eg. Old faithful in Yellowstone national park.
Waimangu geyser in New Zealand.
(Meaning "glowing cloud" in French)
It refers to pyroclastic flow that is accompanied by an ash cloud.
Along sea floor spreading centres
Mid Oceanic ridges (eg Iceland)
Areas of rifting on continental plates (eg. Rift zone in East Africa-- Mt. Kilimanjaro, Mt. Kenya, Mt Cameroon)
At Hot spots where individual plumes of magma rise through the crust .
A hotspot volcano is a volcano situated away from tectonic plate margins .
Hot spots are very hot areas in Earth's Mantle.
They are supposed to be fixed in location.
Eg. Hawaiian Island hotspot,
Easter Island hotspot,
Yellowstone National Park hotspot ,
Reunion Island hotspot(Deccan trap)
Along Subduction Boundaries
Ring of Fire Around The Pacific which includes-
Philippines,Japan,Indonesia,New Zealand Mt. Saint Helens of USA
Highest Concentration of volcanoes ( 2/3)