Unusual seismic activity and gas emissions have been reported at Mount Spurr, a stratovolcano located 130 kilometres west of Anchorage, Alaska. Increased earthquake frequency, melting of snow and ice on its slopes, and rising levels of carbon dioxide and sulfur dioxide emissions have been observed, suggesting movement of magma beneath the surface. The Alaska Volcano Observatory (AVO) has indicated that current activity is more likely to result in an eruption, marking a shift from previous assessments that considered both dormancy and eruption as possibilities.
Scientific Observations on Mount Spurr’s Activity
As per reports, according to the Alaska Volcano Observatory (AVO), the current period of unrest is expected to culminate in an explosive eruption. Matt Haney, Scientist-in-Charge at the U.S. Geological Survey (USGS), told Live Science that past eruptions in 1953 and 1992 occurred at Crater Peak, a vent located 3.2 kilometres from the main summit. The last known eruption from the summit itself is estimated to have occurred over 5,000 years ago, making it unlikely that magma would break through the solidified rock in that area.
Historical records indicate that Crater Peak’s last eruptions sent ash plumes 15,240 metres into the atmosphere, affecting Anchorage with measurable ashfall. In 1992, one of the explosions resulted in 3.1 millimetres of ash accumulating over the city, while the 1953 eruption led to an ash deposit of 6.4 millimetres.
Indicators of an Impending Eruption
Reports suggest that if magma movement continues, volcanic tremor will be the next major indicator of an imminent eruption. Unlike short seismic events recorded over the past year, volcanic tremor involves continuous shaking lasting from minutes to days. Past eruptions in the region, including Mount Spurr’s 1992 event and Mount Redoubt’s 2009 eruption, were preceded by weeks or months of tremor. Scientists are monitoring the situation closely, with any emergence of tremor likely to signal a further escalation toward eruption.
