Volcano news: Mauna Loa volcano (Big Island, Hawaii)
Mauna Loa volcano (Hawai'i): increased shallow earthquakes, alert level raised
Friday Sep 18, 2015 06:47 AM | BY: T
The alert level of the world's largest volcano was raised a notch to "ADVISORY", and the Aviation Color code to "YELLOW" becuase shallow earthquakes have recently appeared in increasing numbers under the volcano. There is no sign that the volcano is about to erupt in a very near future, but it could be a medium- or long-term precursor of a next eruption.
The last eruption of Manua Loa occurred in 1984.
The original report by USGS:
"HVO seismic stations continue to record elevated rates of shallow, small-magnitude earthquakes beneath Mauna Loa’s summit, upper Southwest Rift Zone, and west flank. For at least the past year, the rate of shallow earthquakes has varied but overall has remained above the long-term average. During this same time period, HVO has measured ground deformation consistent with recharge of the volcano’s shallow magma storage system.
Together, these observations indicate the volcano is no longer at a background level of activity. Accordingly, HVO is elevating the Mauna Loa alert level to ADVISORY and the aviation color code to YELLOW."
Wednesday, Sep 18, 2013
A small earthquake swarm occurred last week under the volcano. During 5-7 September, HVO detected about 350 small earthquakes up to magnitude 2.4 in a tightly clustered area at about 7 km depth west of the summit caldera. Only about 25 were strong enough to be located (map). ... [more]
Friday, Jul 05, 2013
Very weak unrest in the form of inflation and seismic activity continues at the largest active volcano of our earth, which has not erupted since 1984. However, this activity is not strong enough to justify a raise of the alert level from green "normal" to yellow "unrest". There is currently no sign that Mauna Loa will erupt any time soon. ... [more]
Wednesday, Jun 12, 2013
The latest update of the USGS mentions that minor inflation of a shallow magma reservoir beneath Mauna Loa may be occurring. Seismicity rates were slightly elevated. However, the level of observed seismicity is far from alarming and the alert level remains at green. No eruption is expected in the near future. ... [more]