Here is your paragraph on Volcanoes!
The eruption of volcanoes is one of the most dreadful natural phenomena. The molten rocks, boiling lava and hot gases penetrate out of that part of the surface which is comparatively weak.
When this material comes out of these spots, an explosion takes place, with thunderous noise, molten rocks, lava and gaseous clouds rise up towards the sky. All this results are in a threat to the environment as well as to life.
Volcanism is not common throughout the world but is limited in the Circum-Pacific belt extending from Andes in South America, through the Cascades and the Aleutians into Japan and then south into the East Indies and New Zealand. There is also an important belt in the Mediterranean, which includes the active volcanoes of Italy.
A volcanic explosion poses a great threat to environment. On an average, a volcano, in an explosion, ejects 150 cubic km of material. This material is of three types: solid material in the form of small and large pieces of rocks, ash particles and also pieces or volcanic bombs which shoot into the sky.
The liquid material called magma comes out of volcano—also known as lava. A huge amount of gaseous material comes out of volcano—steam, carbon dioxide, sulphur in vapour form produce poisonous gases when they combine with other gases. Gases like chlorine, fluorine, etc., are also emitted in large quantities.
The eruptions of volcanoes and lava flows are environmental hazards of the severest type, often taking a heavy toll of plants and animal life. Loss occurs from sweeping clouds of incandescent gases and suspended matter that descend the volcano slopes like great avalanches. When Mont Pele burst in 1902 in the West Indies, its burning material ejected out of it moved in the form of a cloud over the city called St. Piere and only two people out of total 30,000 population survived.
The explosions of Etna and Vesuvious in Italy destroyed many beautiful cities. In 1943, when Paracutin, 320 km west of Mexico city, exploded, it created a mountain 167 metre high. In 1991, volcanic explosions in Japan and Philippines have damaged a lot of property and caused loss of human life and also polluted the environment. Similarly, volcanic activity in the Andaman & Nicobar Islands was responsible for the environmental degradation in this area.