Volcanic Eruptions in the Philippines

What was unusual about the ash plume from the recent Mount Pinatubo eruption?

• It was mostly white and consisted of water vapor.

• It was accompanied by lava flows.

• It was black and dense.

• It contained large amounts of sulfur.

What is the recommended evacuation radius around Mount Pinatubo following the recent eruption?

• 10 kilometers.

• 3 kilometers.

• 5 kilometers.

• 1 kilometer.

Where is Mount Pinatubo located?

• In the southern Philippines, near Cebu.

• On the island of Luzon, northwest of Manila.

• On the island of Mindanao, near Davao.

• In the eastern Philippines, near Leyte.

What was the significance of the 1991 eruption of Mount Pinatubo?

• It caused the formation of a new island.

• It was the smallest eruption in the last 5,000 years.

• It resulted in no significant geological changes.

• It was the largest volcanic eruption in the Philippines in the last 5,000 years.

What typically follows a major eruption in Mount Pinatubo's eruptive cycle?

• Immediate formation of a new caldera.

• A series of small phreatic and lava dome forming eruptions.

• Complete dormancy with no activity.

• A long period of continuous eruptions.

What triggers a phreatic eruption?

• Direct contact of magma with the surface.

• Rapid movement of tectonic plates.

• Over-pressurization of steam from heated groundwater.

• Sudden cooling of magma.

What is the current likelihood of a major magmatic eruption at Mount Pinatubo?

• Certain, with continuous lava flows observed.

• Moderate, with some signs of magma movement.

• Low, with insufficient volcanic earthquakes and sulfur dioxide levels.

• Very high, with immediate evacuation required.

How does sulfur dioxide emission help in assessing volcanic activity?

• It indicates the presence of water vapor.

• It shows the amount of ash in the atmosphere.

• It helps determine the amount of magma present.

• It measures the temperature of the lava.

What was the sulfur dioxide emission level before the 1991 eruption?

• 341 tons per day.

• 13,000 tons per day.

• 1,000 tons per day.

• 5,000 tons per day.

What is the current sulfur dioxide emission level at Mount Pinatubo?

• 13,000 tons per day.

• 341 tons per day.

• 5,000 tons per day.

• 1,000 tons per day.