volcanoes are of great importance because of their potential effects
on nearby populations. During eruptions, a destructive event such
as a debris flow--an avalanche of hot ash, rock and water--can occur,
wiping out anything in its path for many miles. Large debris flow
deposits around the volcano Colima in western Mexico suggest that
many nearby towns may be in great danger if there is a large eruption,
necessitating the formulation, and occasional implementation, of
a wide-scale evacuation plan. Popocatépetl, only 55 km east
of Mexico City and 45 km west of Puebla is within sight of more
than 30 million people. A large eruption would be disastrous, destroying
towns, killing huge numbers of people and blocking much transportation
in the area, particularly airplane traffic.
Paricutin is another famous volcano in the TMVB. Though not particularly
large, its birth, life and death were observed in detail by scientists.
Paricutin sprouted in a central Mexico cornfield in 1943 and grew
to a height of 360 m (1,200 ft) over 9 years--it reached 330 m (1,100
ft) in the first year alone. The volcano covered nearly 26 square
kilometers (10 sq miles) with lava and 256 sq km (100 sq miles)
with ash, destroying the nearby town of San Juan Parangaricutiro
in the process.