How did the volcano erupt in Pompeii?

Answer 1

it depends which one your asking about, but Mt. Vesivus the one that destroyed pompeii happpened because too much lava was built up for several years and finally, at noon, in august, 79 ad, it finally erupted.

Answer 2

The eruption of Mount Vesuvius of 79 AD was of the Pilean type. This involves a pyroclastic flow plus the formation of lava domes. A pyroclastic flow involves gas and rock fragments which create volcanic ash. The flow travels downhill, hugging the ground or spreads laterally. It can reach speeds of up to 450 mph, depending on the density of the flow. The gas can reach temperatures of up to 1,000 °C (1,830 °F).

Scientific studies have shown that the eruptions of 79 AD occurred over two days. On the first day there was a massive eruption which created a column of molten rock and pulverised pumice propelled by gas which was 15 to 30 km (nearly 10 miles to 20.5 miles) high. It was blown southwards by winds and Pompeii was covered with a 2.8 metre (9ft. 2 in.) layer of ash. The column then subsided and the next day there were pyroclastic flows. The biggest ones reached Oplontis to the west and Herculaneum to the north. Pompeii was hit by two smaller ones. In all there were six eruptions. With each subsequent eruption the column was formed again. It is likely that eruptions 3 and 4 were the ones which buried Pompeii. Oplontis and Herculaneum were also covered by ash. Another study indicates that contrary to the previous belief that people died of ash suffocation, heat was the main cause of death. High heat surges can kill people in a radius of 10 km (6 miles) even if they are sheltered in buildings.

There were also minor earthquakes and a mild tsunami in the bay of Naples.