Geobulletin alpha

Source info:

Author:	Matt
Date:	2014-10-21 17:14:00
Blog:	Volcano Science And News Blog
URL:	http://feedproxy.google.com/~r/VolcanoScienceAndNewsBlog/~3/d54eQON3hdI/mauna-loa-priming-for-eruption.html

Summary:

Mauna Loa Priming For EruptionHawaii’s largest volcano, Mauna Loa, is priming for eruption according to the Hawaiian Volcano Observatory (HVO). A statement from HVO says the following:“MAUNA LOA VOLCANO (VNUM #332020)19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)Current Volcano Alert Level: NORMALCurrent Aviation Color Code: GREENSeismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.Monitoring data through the month of September 2014:Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. In late September, a swarm occurred to the west of Moku`āweoweo Crater. The swarm had a maximum magnitude of 2.4 and several events that were large enough to be located. In total, there were up to 150 separate earthquakes that were part of this swarm, most too small to be recorded on enough stations to be accurately located, however we infer that their location is similar to the formal locations of the larger events. The same area had a swarm in September and October of 2013. Several long period earthquakes were present at depths from 50 km to the shallow edifice, with most LP earthquakes between 9 and 15 km depth. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, though similar to the past couple of months. Seismicity rates in the Moku`āweoweo Crater increased over previous months with approximately 50 very small events in the past month at shallow (<5 km) depths. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.Deformation: On Mauna Loa, GPS data continue to show a broad pattern of displacements suggesting inflation. Preliminary modeling shows the data to be consistent with inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper rift zones. Reinflation may have started very slowly in April or May of this year. Displacement rates have been variable, with higher rates in July and August and slowing again in September.”While this does not mean Mauna Loa is at risk for imminent eruption, it does mean that it is more likely than before. Historically, Mauna Loa is Hawaii’s most active volcano, although it has not had an eruption since its last event in 1984. It had erupted about 33 times since its first documented eruption in 1843. Its eruption in 1984 produced some fast moving lava flows which did cause property damage, and it is likely future eruptions will be similar in style.At this time, it would be a good idea for islanders to begin seriously preparing for a future eruption. There is no way to tell where an eruption might begin on Mauna Loa, all surrounding areas are at risk. It is interesting that Kilauea still shows no signs of stopping its eruption, as the constant outflow of lava tends to prevent rapid inflation at Mauna Loa, so this could mean Hawaii’s mantle  plume may be getting a bit more active, but that’s just speculation. If it were true, we might expect to see more activity from Loih’i, and possibly Hualai or Mauna Kea (although activity at Mauna Kea is highly unlikely).

Content analysis:

Geographic context:

Location	Country	Latitude	Longitude
Comoros	KM	-11.6516	43.36
Sulfur	US	38.6263	-119.259
West Summit	US	42.7073	-73.0644

Keywords:

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