Volcanic activity occurred on the north and northeast sides of the Boqueron after the crater formed. More recently flank eruptions have formed two chains of cinder cones. Borqueron's most recent activity started on June 6, 1917. A large earthquake occurred and fissures opened to the north to release a flow of black vesicular andesite lava. On June 10, 1917, the lake inside the crater began to boil and totally evaporated by June 28. Ash and cinder eruptions continued in the crater until November of that year.
Other Local Volcanoes:
Sources of Information:
Fairbrothers, Gregg E. et al, "Temporal Magmatic Variation at Boqueron Volcano El Salvador," Contrib. Mineral. Petrol. 67, 1-9, 1978.
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