Lesson #5 "Volcanoes"
Vesuvius "The Day it Rained Fire"
Pompeii and Herculaneum were bustling Roman cities in 79 A.D. Mt. Vesuvius hadn't erupted in over eight hundred years and the mountain was green with fig and olive trees. Farmers cultivated the sides of the cone. The people were used to earthquakes and didn't pay much attention to the numerous quakes that had been rattling their bowls and plates prior to the eruption. What they didn't know would kill thousands of people that beautiful August day in 79 A.D. Vesuvius was awakening from its long slumber.
Vesuvius awakened with a huge eruption of ash and pumice raining down on the city of Pompeii. Pompeii lay to the south of the volcano and that day the wind was from the north pushing the cloud toward the city. Pompeii was buried in up to 20 feet of pumice and ash. Many animals and people were suffocated and buried alive. Many people though, did survive the initial eruption. Some decided to flee but many stayed.
The city of Herculaneum lays to the west of the volcano and much closer to Vesuvius than Pompeii. Herculaneum was a beautiful beachside resort city in 79 A.D. Herculaneum was barely touched by the first eruption. In fact, about only one inch of ash and pumice fell on the city during the first eruption.
The next eruption was the deadly one. This eruption blanketed the whole surrounding area with very hot, turbulent, twirling gases and ash. This glowing cloud was very heavy and hugged the ground as it flowed down the side of Vesuvius. The temperatures of this pyroclastic flow were probably around 700 degrees F. and at a speed of over 70 miles per hour animals and people could not out run it. With temperatures this high everything in its path is killed instantly.
Herculaneum didn't get lucky this time. It was buried in an extremely hot flood of volcanic mud. This steam filled volcanic mud buried the city with a layer over 50 feet high. Pompeii suffered through this eruption also. Over 20,000 citizens died in the pyroclastic flows only hours after the initial eruption.
A man by the name of Pliny the Younger wrote an account of this eruption as he viewed Vesuvius from Naples to the northwest of the volcanic mountain. His account was probably the first one ever written. His uncle, Pliny the Elder, died in the second eruption that day. Pliny the Elder was a commander of a fleet of Roman battleships. He was also a naturalist, a person who studies natures spectacles and writes about them. He was viewing the eruption when he was probably over come by hot gases.
Today Vesuvius is the most visited volcano in the world. The mountain that hadn't erupted in about eight hundred years has erupted many times since. In 1631, Vesuvius belched out another pyroclastic flow, which has been the worst eruption since 79 A.D. Many tourists pay to make the very difficult climb to the crater to view the steaming lava inside the volcano. They flock to the excavated ruins of Pompeii and Herculaneum to view the plaster casts of bodies as they lay when they died almost two thousand years ago during the day that rained fire.
1. What caused the death of so many people during the second eruption of Vesuvius?
2. What is a pyroclastic flow?