GEOLOGY

Detailed explanation-1: -A pyroclastic flow can pour over the lip of an erupting vent, or it may form when an ash column becomes too dense to continue rising and falls back to the ground.

Detailed explanation-2: -A pyroclastic flow is a dense, fast-moving flow of solidified lava pieces, volcanic ash, and hot gases. It is extremely dangerous to any living thing in its path.

Detailed explanation-3: -Pyroclastic flows are hot ‘density currents’ consisting of mixtures of rock debris and gas that flow along the ground at high speed.

Detailed explanation-4: -Volcanic ash can create eye and upper airway irritation. Ashfall can cause minor to major damage to vehicles and buildings, contaminate water supplies, disrupt sewage and electrical systems, and damage or kill vegetation.

Detailed explanation-5: -Volcanologists use the word ‘tephra’ as general term for volcanic rock fragments irrespective of grain size produced during an explosive eruption. Volcanic ash is fine tephra, and terms such as lapilli, blocks, and bombs are used to categorize larger fragments.