Magma is the core material of the earth in the form of liquid, viscous, and very hot. Magma activity caused by high temperature magma and the amount of gas contained in them. Magma comes out towards the earth's surface is called lava.
Volcano is a place on the earth's surface that had or still oozing magma. There are three kinds of volcanoes seen from the shape and occurrence.
a. Cone volcanoes (strato). Shaped like a cone, occur because of the eruption and melt (etusi) interchangeably. This species is widely available in Indonesia. Example: Mount Merapi in Indonesia.
b. Shield volcano or a shield or aspit. Shaped like a shield, due out melt and form a very gentle slope. Example: Mount Mauna Loa (Hawaii).
c. Maar volcanoes. Shaped like a small lake (Crater Lake). Occurs due to the eruption (explosive). Example: Mount Lamongan (East Java), Eifel Mountains (France), and the plateau in Central France.
According to the activity, the volcano were divided into three groups:
a. Active volcano, the mountain is still working, the crater always remove smoke, earthquakes, and eruptions. Example: Mount Stromboli
b. Mount died. Mountain is not erupting again. Example: Patuha and Sumbing
c. Mount a break. Volcano erupt at any time and then break back. Example: Mount Ciremai and Kelud.
