Seismic activity and changes in Taal Volcano’s main crater lake have been observed on Monday despite the volcano under alert level 1 (abnormal), the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
In an advisory, the Phivolcs said 50 weak tremor episodes were recorded from 5 a.m. to 3 p.m., occurring at shallow depths. Seismic activity describes earthquake occurrences in the volcano.
This signals increased hydrothermal activity beneath Taal Volcano island.
“Tremors are typically not recorded,” Phivolcs director Renato Solidum told the Philippine News Agency (PNA) on Monday night.
The Phivolcs recorded 68 shallow tremor episodes in the volcano island since Feb. 13.
Solidum said the main crater lake is becoming more acidic and hotter.
Local government units are advised to prepare in case of the volcano’s renewed unrest and to assess previously evacuated barangays around Taal Lake for damages.
The public is urged to observe precautions due to possible ashfall, ground displacement across fissures, and minor earthquakes in the event of a phreatic eruption.
According to the advisory, geochemical data on the main crater lake indicate continuous acidification of lakewater from a pH 2.79 to pH 1.59 between January 2020 and February 2021, an unseasonal temperature high of 77 degrees Celsius and CO2/H2S gas flux ratios consistent with shallow magma degassing.
Phivolcs said there are increased possibilities of sudden steam-driven or phreatic explosions, lethal accumulations, or expulsions of volcanic gas and minor ashfall from the main crater that can occur and threaten areas within the Taal Volcano island.
Entry into the island, Taal’s Permanent Danger Zone, especially the vicinities of the main crater and the Daang Kastila fissure, must remain strictly prohibited, Phivolcs added.
Pilots are advised to avoid flying close to the volcano as airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircraft.
Courtesy of pna.gov.ph
A volcano in the far eastern end of Russia that was thought to be extinct may now have awakened — and its eruption could be as severe as the one that destroyed the ancient Roman settlement of Pompeii, according to scientists.
In the fall of 2017, seismic activity was discovered underneath the Bolshaya Udina volcano, which was thought to be inactive for decades.
Since scientists began monitoring the area in 1961, only a single weak activity has been detected, according to the Russian Academy of Sciences (RAS).
After the initial activity was discovered, a detailed investigation was launched, which included four temporary seismic stations being placed near the volcano.
Over a two-month period from May to July 2018, 559 localized events were detected in the area of the volcanoes, according to a study that reported the investigation’s findings.
The continued activity led the study to conclude that the volcano may have to be reclassified as “active” given the possible presence of “magma intrusions with a high content of melts and fluids.”
In addition to those events, a 4.3-magnitude earthquake occurred under Udina in February — the strongest to be recorded in that area, according to RAS.
Long-dormant volcanoes pose great risks, according to Ivan Koulakov, the lead scientist investigating the volcano.
“When a volcano is silent for a long time, its first explosion can be catastrophic … Recall Pompeii,” Koulakov told RAS, referencing the ancient Roman settlement Pompeii that was totally destroyed by the eruption of Mount Vesuvius, which was dormant for thousands of years before.
Koulakov also explained that the eruption can have far-flung effects.
“A large amount of ash is thrown into the air, it is carried far away, and not only the surrounding settlements but also large territories all over the planet can suffer,” he said.
This ash can affect air travel and climate, according to CNN.
He pegged the chances of an eruption at 50 per cent.
“At any moment, an eruption can occur,” Koulakov told CNN.
Courtesy of globalnews.ca