The main form of volcanic activity, but also broken down into three kinds: (1) quiet formula: Eruption. Only a lot of red-hot lava from the volcano quiet overflow flows slowly along the hillside, as if boiling the rice soup from the cooking pot of boiling inside out, like diarrhea. Overflow to the base of the main magma, magma high temperature, low viscosity, easy flow. With less gas, no explosive phenomena of various volcanoes in Hawaii as its representative, also known as Hawaiian types. Such people can enjoy the volcanic enjoy. (2) the bursting of formula: Volcanic eruption, resulting in violent explosions, and spew a lot of gas and pyroclastic material, to intermediate-acid magma emitted by the main magma. December 16, 1902, the West Indies, Pei-lei volcanic eruption shook the entire world. It is viscous magma emitted at the same time emitting a large number of pumice stone and red-hot volcanic ash. The eruption caused the death of 26,000 people, in the case of such, also known as Pei-lei-type. (3) intermediate-type: Part of a quiet type and the bursting of the transition between the eruption type. Such types are mainly in mafic lava eruption. If the explosion, the explosive power is not great. May be several months or even years, long-term smooth eruptions, and in accompanied by intermittent outbreaks of inter-characterized. To get near the west coast of Italy on the Lipari Islands, the volcanic Sitelangbo was represented. The volcanic eruption approximately every 2-3 minutes, once a night, 50 miles away can still see the volcanic eruption of the Guang-yan and therefore I known as the "Mediterranean Lighthouse." Some people think that China's Heilongjiang Province, belongs to this type of volcano Wudalianchi.