GEOLOGY

Detailed explanation-1: -A volcano is a feature in Earth’s crust where molten rock is squeezed out onto the Earth’s surface. This molten rock is called magma when it is beneath the surface and lava when it erupts, or flows out, from a volcano. Along with lava, volcanoes also release gases, ash, and solid rock.

Detailed explanation-2: -Volcano. According to the United States Geologic Survey, there are approximately 1, 500 potentially active volcanoes worldwide. Most are located around the Pacific Ocean in what is commonly called the Ring of Fire. A volcano is defined as an opening in the Earth’s crust through which lava, ash, and gases erupt.

Detailed explanation-3: -A hot spot is an area on Earth over a mantle plume or an area under the rocky outer layer of Earth, called the crust, where magma is hotter than surrounding magma. The magma plume causes melting and thinning of the rocky crust and widespread volcanic activity.

Detailed explanation-4: -When magma flows or erupts onto Earth’s surface, it is called lava.

Detailed explanation-5: -If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. The slow cooling process allows crystals to grow large, giving intrusive igneous rock a coarse-grained or phaneritic texture. The individual crystals in phaneritic texture are readily visible to the unaided eye.