First, the cause of volcanic eruption
The molten material on the earth is ejected under pressure. Because the magma contains a large number of volatiles and the confining pressure of the overlying strata, these volatiles cannot overflow when dissolved in the magma. When the magma rises close to the surface, the pressure decreases and the volatiles are released sharply, thus forming a volcanic eruption. Volcanic eruption is a peculiar geological phenomenon, a manifestation of crustal movement, and the strongest display of heat energy inside the earth on the surface.
Second, the advantages and disadvantages of volcanic eruption
Can create some land resources for mankind. After the magma flows to the seaside, it solidifies there, becomes land and expands its territory. If the volcanic eruption is strong, it can expand several square kilometers a year. Land resources are mineral resources. There are quite a lot of mineral resources formed by volcanism, including nonmetallic resources and metallic resources. Many minerals are related to volcanic eruptions. If you are more interested, you will find gems. Some gems are erupting from volcanoes, so there are so many benefits. I think they explode occasionally.
Third, does it have an impact on the economy?
I think it will lead to the closure of local scenic spots, but relatively speaking, if the volcano erupts, it will be very beneficial to the local economy. The saying that relying on mountains to eat mountains and relying on the sea to eat the sea is still very reasonable, and it will also promote the development of tourism and attract many tourists, which can be said to have played a significant role in the local economy.
So I think volcanic eruption destroyed the geographical environment and affected economic activities. However, it has also brought benefits to mankind.