Signs Point to Magmatic Activity Within Volcano

Recent tremors and the release of incandescent gases at the Turrialba Volcano, about 35 kilometers northeast of San José, could be indicative of magmatic activity.

Experts from the NationalUniversity’s Vulcanological and Seismological Observatory of a (OVSICORI) last Sunday night photographed a “long, reddish vapor trail” seeping out of the volcano’s crater, moving west and extending up to 60 kilometers from the mouth of the volcano.

According to an OVSICORI report, the gasses in the vapor trail, composed mostly of sulfur, reached temperatures of 320 degrees Celsius.

The trail’s searing, reddish tint might be explained by small lava particles that have mixed with the gasses inside the volcano, the report said.

Elicier Duarte, an OVSICORI scientist, said that red fragments could be coming from a cavity deep inside the volcano adding that the presence of the particles, though, could also be due to rising magma inside the mountain.

This week, seismologists also recorded small tremors and heard “deafening, jet engine-like noises” at the volcano. On Tuesday, a 1.5 magnitude tremor rattled the area briefly at 9:18 a.m.

Duarte said that these shakes and sounds are also signs that the volcano is “likely magmatic.”

The Turrialba Volcano began showing increased signs of activity in early January when ash eruptions forced dozens of evacuations in communities around the volcano’s skirts. Scientists described the activity as the first such display in more than 140 years.

Since then, teams of experts have monitored the volcano closely, measuring gases and looking for possible signs of additional activity.

–Mike McDonald