Eruptive history of the Tacaná volcanic complex

Abstract

Tacaná is the northernmost volcano of the Central American Volcanic Arc, and one of the four volcanic structures of the Tacaná Volcanic Complex (TVC), from oldest to youngest: Chichuj, Tacaná, and San Antonio volcanoes, and Las Ardillas dome. Geologic and radiometric data show that volcanic activity of the TVC began around 225 ka with the construction of Chichuj volcano within the 2 Ma old San Rafael Caldera. The edifice of Tacaná began its construction west of Chichuj volcano around 50 ka. San Antonio volcano, and Las Ardillas Dome formed southwest of Tacaná volcano during Late Pleistocene. Effusive and explosive eruptive activity has alternated from all eruptive centers of the complex. Flank collapses of Chichuj, Tacaná, and San Antonio edifices have generated debris-avalanches. At least four plinian -subplinian events—two of which rank ~5 on the Volcanic Explosivity Index (VEI)—and nine other smaller explosive eruptions occurred at Tacaná during the Holocene, the most recent one around 150 year BP. The 1949 and 1986 phreatic explosions from Tacaná attracted scientific and public attention to the complex. At present, Tacaná represents the second most dangerous volcano in Mexico after Popocatepetl.