Mount Pinatubo Info on Mount Pinatubo Mount Pinatubo
Mount Pinatubo
Info on Mount Pinatubo • Mount Pinatubo is an active stratovolcano in the Cabusilan Mountains on the island of Luzon, near the tripoint of the Philippine provinces of Zambales, Tarlac, and Pampanga. Before the volcanic activities of 1991, its eruptive history was unknown to most people. It was heavily eroded, inconspicuous and obscured from view. It was covered with dense forest which supported a population of several thousand indigenous people, the Aetas, who fled to the mountains during the Spanish conquest of the Philippines.
The effects of the eruption • The volcano's Plinian / Ultra-Plinian eruption on 15 June 1991 produced the second largest terrestrial eruption of the 20 th century after the 1912 eruption of Novarupta in the Alaska Peninsula. Complicating the eruption was the arrival of Typhoon Yunya , bringing a lethal mix of ash and rain to areas surrounding the volcano. Successful predictions at the onset of the climactic eruption led to the evacuation of tens of thousands of people from the surrounding areas, saving many lives, but the surrounding areas were severely damaged by pyroclastic flows, ash deposits, and subsequently, by the lahars caused by rainwaters re-mobilizing earlier volcanic deposits causing extensive destruction to infrastructure and changing the river systems months to years after the eruption.
The effects of the eruption • The effects of the eruption were felt worldwide. It ejected roughly 10, 000, 000 tonnes of magma, and 20, 000 tonnes Sulphur • It injected more particulate into the stratosphere than any eruption since Krakatoa in 1883. Over the following months, the aerosols formed a global layer of sulfuric acid haze. Global temperatures dropped by about 0. 5 °C (0. 9 °F) in the years 1991 -93, and ozone depletion temporarily increased substantially.
1991 activities leading to the eruption • On March 15, 1991, a succession of earthquakes were felt by villagers on the northwestern side of the volcano. Further earthquakes of increasing intensity were felt over the next two weeks, and it became clear some kind of volcanic activity was likely. On April 2, the volcano awoke, with eruptions occurring near the summit. Over the next few weeks, small eruptions continued, dusting the surrounding areas with volcanic ash. Seismographs recorded hundreds of small earthquakes every day
1991 eruption • The second-largest volcanic eruption of the 20 th century, and by far the largest eruption to affect a densely populated area on June 15, 1991. The eruption produced high-speed avalanches of hot ash and gas, giant mudflows, and a cloud of volcanic ash hundreds of miles across.
• https: //www. youtube. com/watch? v=MQIkeyh c 8 Is#t=631
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