Presentation on theme: "The Eruption of Mount St. Helens"— Presentation transcript:
1 The Eruption of Mount St. Helens BeforeAfterInsert pictures here.
2 Mount St. Helens was a beautiful place to hike, camp, and enjoy . Mount St. Helens was a beautiful place to hike, camp, and enjoy. It was considered one of the most symmetrical mountains in the Cascade range.Insert pictures here.
3 The first indication that the volcano was awakening was a series of earthquakes. The first quake was on March 20, Then many other quakes followed. It was hard to tell when one was finished and another began.Insert pictures here.
4 Small explosions began on March 27 which blew out ash and steam Small explosions began on March 27 which blew out ash and steam. The snowy mountain top looked dirty.Insert pictures here.
5 On the north side of the mountain, a bulge began to grow On the north side of the mountain, a bulge began to grow. It was bulging five to six feet higher each day.Insert pictures here.
6 On May 18, 1980, the mountain’s bulge suddenly blew. Insert pictures here.
7 The blast was caused by an earthquake which opened a crack in the bulge, letting in air to the superheated water inside the mountain. The water exploded into steam instantly, blasting off 1200 feet of the top and north side of the mountain. The force of the blast blew down and scorched 150 square miles of forest.
8 Notice the two men in the circle to get an idea of how huge the trees were. Insert pictures here.
9 Next, the loosened rock and mud of the mountain slid down into Spirit Lake and the Toutle River valley.Insert pictures here.
10 The volcano then spewed ash, pumice, and gas into the sky The volcano then spewed ash, pumice, and gas into the sky. It traveled eastward on the wind and made one town eighty miles away so dark that the street lights turned on during the day.Insert pictures here.
11 By the end of May 18, countless lives of animals and plants had lost their lives, including 57 people. The volcano presently continues to have much less dramatic eruptions.Insert pictures here.
12 References Pictures for the presentation can be found at these websites. LiontracksBefore and after photographMount St. Helens August 18, 2003 from Hopkins Hill ViewpointBefore photographs: a year before and one day beforeMount St. Helens Precursory ActivitySeismic chartBulging mountain photographPredicting Volcanic Eruptions by Helen StewartExploding volcanoUSGS AftermathDowned treesUSGS Photo by T. J. CasadevaltMudslide viewSudden Destruction in MayEruption after blastDokumentation uber den Ausbruch des Mount St. HelensPeacefully steaming after 1980