Volcanoe and Ash
– ASH FROM A VOLCANO: IT MAY REMAIN ALOFT –
The 1982 eruption of Mexico’s El Chichon volcano sent vast quantities of ash high into the stratosphere. If a University of New Mexico scientist is correct, the ash which went up hasn’t all come down yet. Most scientists assume that volcanic ash falls to earth within a year or two after an eruption. But Frans J.M. Rietmeijer says that he can show that tiny particles collected in 1985 by a balloon above Texas had come out from El Chichon.
What’s more, he believes that because volcanic particles are flat and fall more slowly than spherical particles, thev may remain aloft for a hundred years or more. The balloon was originally designed to collect particles of meteoric origin. It took samples of the air at an altitude of 35 kilometres – near the top of El Chichon’s plume of ash. Rietmeijer says the particles that he analysed chemically match the ash from the volcano.
Mark the best choice.
1. Line 10, ‘they’ refers to .
a) spherical particles b) particles of meteoric origin c) volcanic particles d) research balloons
2. Line 10, ‘aloft’ probably means .
a) up in the air b) flat c) in the ash form d) volcanic
3. Which of the following cannot be concluded from the first paragraph?
a) There was a disaster in Mexico in 1982.
b) There may still be ash in the atmosphere today.
c) Scientists agree on the fact that the ash from the volcano hasn’t all come down yet.
d) Scientists may sometimes be wrong.
4. According to the second paragraph, .
a) spherical particles fall to earth faster than flat particles
b) volcanic ash is composed of spherical particles
c) ash particles are quite large
d) volcanoes are made up of particles of meteoric origin
5. The main idea of the second paragraph is that .
a) the balloon was originally designed to collect particles of meteoric origin
b) most scientists have no idea about the eruption of El Chichon
c) there’s evidence that some volcanic ash will fall to earth even a hundred years later
d) all volcanic ash particles should be analysed chemically