text chapter 7 quiz natural disasters
Violent causes of death from volcanic eruptions include _______________.
All of these choices are correct
The two most active Cascade Range volcanoes over the past 4,000 years are _______________.
Mt. St. Helens and Mt. Shasta
What is the volcanic explosivity index (VEI) of a Yellowstone super-eruption?
VEI of 8
Most of the people killed by the Mount St. Helens eruption of 1980 __________.
had gone around barriers meant to keep people out of 'harms' way
Dome collapse, overspilling crater rim, direct blast and eruption column collapse are all ways to generate __________.
pyroclastic flows
Why are low-latitudes the most dangerous latitudes to have a large volcanic eruption occur?
Ash and gases from low-latitude eruptions are spread around Earth to the greatest degree.
What was the origin of the gas that killed 1,700 people in Cameroon in 1996?
It leaked upward from basaltic magma underlying a lake.
In 1985, __________ produced a minor eruption that melted part of a glacier near its summit, sending a lahar down its slopes and killing at least 22,000 people.
Nevado Del Ruiz, Colombia
The Mt. Pinatubo endangered people, animals, and property when its 1991 eruption resulted in __________.
lahars and pyroclastic flows
Active volcanoes today in Oregon and Washington, including Mt. St. Helens, result from _________________.
the subduction of the Juan de Fuca Plate beneath North America
Seafloor spreading generates __________ magma
Basaltic
During the 1990s, hundreds of trees were killed at Mammoth Mountain, California, by the diffuse emission of _________ gas.
CO2
In 1883, __________ exploded and the resulting tsunami killed 36,000 people on Java and Sumatra.
Krakatau
During the summer of 1783, the greatest lava eruption of historic times poured forth at _________, accompanied by the release of an enormous volume of gases that enshrouded much of northern Europe in a "dry fog" or blue haze rich in SO 2 (one of the visible components of today's urban smog).
Laki, Iceland
In August 1986, a gigantic volume of __________ belched forth from Lake Nyos in Cameroon and swept down the adjacent valleys asphyxiating 1,700 people.
carbon dioxide
The Toba eruption 74,000 years ago may have __________.
caused a great reduction in the worldwide human population
On 8 May 1902, a massive eruption of __________ killed 30,000 people in the town of St. Pierre.
Mont Pelée, Martinique,
A genuine success story of advance warning before a large eruption occurred in the Philippines in 1991 before the climactic eruption of _________________.
Mt. Pinatubo
Volcanic eruptions with which of the following VEIs happen the most often?
VEI of 3
Several geologic phenomena are being studied as signs of an impending volcanic eruption. These include seismic waves, ______________, and the release of gases.
ground deformation