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Reporting System

While we were gone…

A lot happened while we were down. Sunspot 1402 decided to show its strength as it crossed over the visible corona. From the start it began shooting out M class flares, and just as it was leaving it did the same. The strongest flare it released was an X5 class flare, which produced a large CME that mostly hit Earth. On top of several other C and M class flares, the magnetic field has had to work over time on certain occasions as of late.

The volcanic situation is interesting as always, with a few new candidates appearing on the scene, with a few old timers like Etna continuing on and on.

The largest earthquake we’ve seen since we’ve been gone was a 7.4 magnitude quake that struck Mexico on the 20th, following a 6.9 that struck Japan just a few days earlier, and prior to a 6.6 that struck PNG late on the 21st. The 188 day theory did not hold true, unfortunately. The idea was that there was a megaquake separated by a 7 mag quake in this pattern, since February 27, 2010. While we did have some 6 magnitude action and a 7.4, it still isn’t enough to say that this cycle held out. I think that it may be indicative of a pattern of movement roughly every 6 months or so, but rounding it down to the day, or hour, is likely to yield no real results. That’s all at present. The equinox has come, and now shall the colours of 2012 really start to come through.

– Admin

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March 23, 2012 Posted by | Seismic, Solar, Volcanic | , , , , , , , , , | Leave a comment

Volcanologists Monitor Swarm of New Tremors at El Hierro

The submarine eruption south of El Hierro Island could be in a process of change: While visible activity on the sea surface above the vent, as well as harmonic tremor signal (thought to be more or less proportional to erupting magma flux) have nearly ceased, the number of earthquakes under the island has increased sharply since yesterday.

On 15 February, more than 20 quakes were measured. Most of the earthquakes were very small, well below magnitude 2, and were clustered beneath the NW and SW sectors of the island at depths of around 10 km. There is no conclusive interpretation of this measurement.

A possible (and usually assumed) scenario is that rising new magma from the mantle reservoir is creating new intrusions and rupturing rock to create pathways in the crust under El Hierro, not using the same paths as until now. That would explain why less magma is currently being erupted at the current vent(s). In that scenario, the eruption will continue, perhaps even from a different vent, and an increase in magma output is going to be expected any time soon. However, this is speculation.

The earthquakes could as well be related to some other (known or unknown) process, e.g. gravity-induced adjustments that respond to pressure changes and occur within previously ruptured areas of the crust beneath the island.

The next days or weeks will show what happens next.

…(Volcano Discovery)

February 17, 2012 Posted by | Science, Volcanic | , , , , , , | 1 Comment

6.3 Magnitude EQ – Near the Coast of Central Peru

At approximately 05:11:01 UTC on Monday, January 30th, an earthquake based on land struck at a depth of 39.2 km (24.4 miles) off the coast of Central Peru, 15 km (9 miles) SE of Ica, Peru, and 96 km (59 miles) SSE of Chincha Alta, Peru. Coords: 14.179°S, 75.644°W

United States Geological Survey – The event has been reviewed by a seismologist and confirmed, at present, to be a 6.3 magnitude earthquake at a depth of 39.2 km (24.4 miles). The European Mediterranean Seismology Agency is in agreeance with the earthquake parameters provided by the USGS.

…(USGS) (EMSC)

The quake occurred shortly after midnight local time (1 a.m. ET) and was centered about 9 miles southeast of the city of Ica and about 170 miles south-southeast of Lima.

Witnesses said the quake shook buildings in coastal Lima, Peru’s capital. Although there were no reported injuries or damage, local radio said residents near the epicenter were alarmed and ran outside their homes when they felt the quake. Power was out in nearby Pisco, the radio said.

“We felt a terrible earthquake that’s really scared us,” Ica resident Blanca Cabanilla told the local radio. “It was similar to what happened to us in 2007.”

An 8.0 quake in 2007 killed more than 500 people in Ica and wrecked thousands of homes.
…(Reuters)

January 31, 2012 Posted by | Seismic | , , , , , | Leave a comment