Mt Pinatubo Case Study
This caused the shaking and squeezing of the Earth’s crust beneath the volcano. At Mount Punctuation, scientists recorded a landslide, some local earthquakes, and a short-lived increase in steam emissions from a pre-existing geothermal area, but otherwise the volcano seemed to be undisturbed.
In March and April 1991, however, magma started rising towards the surface from more than 20 miles (32 SMS. ) beneath Punctuation. This triggered more small earthquakes and caused powerful steam explosions that blasted three craters on the north side of the volcano.
Thousands of mall earthquakes occurred beneath Punctuation throughout April, May, and early June 1991 , and many thousand tons of noxious sulfur doodle gas were also emitted by the volcano. Scientists had been able to forecast Pantsuit’s 1991 eruption and this resulted in the saving of many lives and much property. Commercial aircraft were warned about the hazard of the ash cloud from the June 15 eruption, and most avoided it.
Although much equipment was successfully protected, buildings on two U. S. Military bases in the Philippines–Clark Air Base and Cubic Bay Naval Station?were heavily damaged by ash.
Nearly 20 million tons of sulfur dioxide were injected into the stratosphere and the spread of this gas cloud around the world caused global temperatures to drop temporarily (1991-1993) by about 0. ICC.
About 20,000 Eat highlanders, who had lived on the slopes of the volcano, were completely displaced, and most still Walt In resettlement camps for the day when they can return home. About 200,000 other people who evacuated from the lowlands surrounding Punctuation before and during the eruptions have returned home but face continuing threats from Lars (minnows) Tanat nave already Durable numerous towns, villages Ana Title
On June 7th 1991, the first magma reached the surface of Mount Punctuation but because it had lost most of the gas contained in it on the way to the surface, the magma merely oozed out to form a lava dome. However, on June 12th, large amounts of gas-charged magma reached the surface and exploded in the volcano’s first spectacular eruption. When even more highly gas charged magma reached Pantsuit’s surface on June 1 5th, the volcano exploded in a massive eruption that ejected more than 5 cue. SMS.
Of volcanic material. The ash cloud from this huge eruption rose 22 miles (35 SMS. ) into the air.
A blanket of volcanic ash and larger pumice pebbles blanketed the countryside. Fine ash fell as far away as the Indian Ocean, and satellites tracked the ash cloud several times around the globe.
Huge avalanches of red hot ash, gas, and pumice fragments called parasitic flows roared down the sides of Mount Punctuation, filling the deep valleys with fresh volcanic deposits as much as 660 Ft. (200 m. ) thick. The eruption removed so much magma and rock from below the volcano that the summit collapsed to form a large volcanic depression or caldera 1. 6 miles (2.
5 SMS. ) across.