Nevada Del Ruiz Volcano example essay topic

Nevada Del Ruiz Volcano The volcano that I am doing my report on is the composite-cone Nevada Del Ruiz volcano, located in the South American country of Columbia. The location of the volcano is near the Nazca and American tectonic plates which merge near the northwest coast of the South America continent. Nevada Del Ruiz is located in the Andes mountains and is the highest and the most northern volcano in South America. The volcano's summit is at an elevation of over 17,000 feet above sea level and because of the cold climate at that elevation, the summit is covered with over 15 square miles of snow and ice. This was surprising after finding out that the volcano is located only 300 miles from the Earth's equator, where it is the most consistently hot climate on the earth. Beginning in November of 1984, the volcano started to show signs that it would be erupting.

Small eruptions, explosions and earthquakes were the signs of an emerging volcano. On November 13, 1985, at 9: 00 PM a large explosion from Del Ruiz's summit crater sent a bunch of hot steam, smoke and ash called a Pyroclastic flow across the summit with all the ice and snow on it. It ended up totaling over 24 feet, or almost 5 times my height of that ash on top of the summit covered with snow and ice. That day, it had been raining heavily and with the rain and the heat, a bunch of the ice cap on top of the volcano's summit started to melt.

Over 1 and a half square miles of ice and snow that was over 12 feet thick, melted and started draining into the valleys and channels on the sides of the volcano. As the ice melted, huge boulders and rocks the size of cars started to come down in these runoffs off the mountain. Some of the ice pieces just separated and didn't melt, and pieces of ice that were 6 feet across were found over two miles from where they first loosened off the ice sheets at the summit. When this happens on a volcano the flow of rock, water and ash is called a lahars. The smaller lahars ended up merging into bigger valleys and then went into the six major river valleys at the base of Nevada Del Ruiz. As the lahars came down the river valleys, even more soil and rocks and other debris came off the banks of the river and made the lahars even bigger until they got as deep as 150 feet or half a football field and were going over 40 miles per hour!

Just the sound of lahars made houses shake and people could barely hear each other, even if they shouted. The lahars traveled about 70 miles downstream and anybody that didn't have their house over 150 feet higher than the river got flooded out of their house or washed away. When it was all over, more than 23 thousand people died and over 5 thousand people were injured. More than 5 thousand homes were wiped out and the town of Armero had over 21 thousand or 75% of its towns people killed. That is two thousand more people than it takes to fill the America West Arena.

The first surge of lahars hit the town of Armero at 11: 23 pm and the last hit at 1: 00 AM. The largest lahars that came right before midnight, passed through the town with most of the people asleep and unable to get around in the dark. That huge lahars was up to 15 feet high and was basically a wall of mud. When it was over, most of the 21 thousand people that died had been buried in mud. I interviewed people like my parents who would remember the news reports from that time and they said there were lots of reports showing people buried up to their heads in mud. Even though they could breathe, they died because they were crushed by the weight and pressure of the mud they were buried in.