The Gambia has no migrating wildebeest, giraffes or any of the large animals commonly associated with Africa. However without leaving your hotel you can see a breathtaking variety of bird life, in addition to monkeys and lizards. Baboons and crocodiles can be seen nearby and then far up the river, hippos.
As the gasses collect in the magma chamber, the pressure rises. It is possible for the pressure to rise so much that the chamber cannot contain the magma and it erupts explosively. Some US Parks that have active volcanoes formed as the result of subduction related processes are: 1  Crater Lake National Park, OR.
When it reaches the surface, a volcano is formed. The magma flows out as lava, sometimes explosively. The majority of the world's volcanoes are associated with subduction zones. Since subduction zones represent plate margins, volcanoes tent to occur in lines, like the Cascade Range volcanoes or those on the Aleutian Peninsula. Once in a great while, a new volcano will form. This usually happens when an active underwater volcano produces enough lava to break the surface, such as Surtsey in Iceland in 1963.