Emission of black to gray ash continued through late April. Clouds and haze completely obscured the volcano on 9 days during April and limited visibility to only a few hours on most other days.

Activity usually consisted of mild to moderate emission of gray ash. Stronger activity occurred on 2 April, when black ash rose about 1000 m during the morning, but activity had declined by late afternoon. Dark gray ash emission was visible between 0730 and 0830 on the 20th (to 1000 m above the summit) and at about 1030 on the 23rd (to 550 m). Small amounts of fine ash fell on Antigua on 17, 18, 19, 21, and 25 April. Incandescence was seen before dawn on 15 and 20 April.

At 1120 on 15 April an earthquake centered approximately 15 km NE of Fuego was felt at intensity 3 in Antigua, 3 km from the epicenter, for about 10 seconds. A small 1.5-second event was also felt in Antigua at 1822 on 26 April.

Geological Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows.

Information Contacts: P. Newton, Antigua.