Landforms at Constructive Margins Sea floor Spreading Constructive margins occur where two plates diverge from each other and new crust is created in the boundary. Sea floor spreading occurs in the mid Atlantic where the north and south American plates are being pulled apart by convection currents from the Eurasian and African plates. This may cause huge rift valleys initially to occur on the sea floor, but molten rock and magma from the mantle rises …showed first 75 words of 480 total…

…showed last 75 words of 480 total…in ash. The ash that is in the air stops sunlight coming through which means 24 hour darkness, and the ash also promotes health defects, especially to their breathing. The are also good sides to this. Intense heat is generated deep underground creates bubbling hot spring and mud pools. Iceland has the most Solfataras w! hich are volcanic vents and hot springs in the world, and many towns are heated by underground hot water. ------------------------------------------------------------------------ **Bibliography**