Geologic Background:
Volcan de Izalco, El Salvador's youngest
volcano, originated in 1770 AD on the southern flank of
Santa Ana volcano. Frequent strombolian eruptions from
the volcano provided a night-time beacon for ships,
causing the volcano to be known as the "Lighthouse of the
Pacific." During the two centuries prior to the cessation
of activity in 1966, Izalco built a steep-sided,
650-m-high stratovolcano truncated by a 250-m-wide
crater. Izalco, whose products are geochemically distinct
from both Santa Ana and its fissure-controlled flank
vents, was one of the most frequently active volcanoes in
North America, erupting basaltic to basaltic-andesite
pyroclastics and lava flows. Lava flows, mostly erupted
from flank vents, were deflected southward by the slopes
of Santa Ana volcano to the north, were restricted to
within 5 km of the summit of Izalco.
Historic Activity:
- At least 50 eruptions between 1770 and 1952.
Recent Activity:
- Most recent eruption in November 1966. Fumarolic
activity since.
Data Sources:
- Global Volcanism Network (V. 24, No. 2, and V. 24,
No. 12).
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