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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

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

Seismic swarm at San Salvador volcano alarms authorities

Authorities today ruled El Salvador declare an emergency for low-magnitude earthquakes that have shaken the Salvadoran capital, all centered in the San Salvador volcano, eight of them felt by the population and the strongest of 3.3 degrees on the Richter scale.

“There is no evidence that we are facing a potential emergency,” said Minister of Environment and Natural Resources, Herman Rosa Chavez, in a press conference in which he reiterated that no volcanic tremor, but tectonic.

“We did analysis of temperature in the area and there is no evidence that this is associated with volcanic activity, this has to do with the activation of local faults, which is something that happens and has happened before,” he said.

The eight tremors felt by the population have reached levels of between 2.2 and 3.3 degrees on the Richter scale, according to the National Service of Territorial Studies (SNET), which has recorded at least 25 microearthquakes.

The first quake was felt that reached 2.6 degrees and was registered at 01.22 local time (7.22 GMT), and most recently, of 2.7 degrees, at 15.50 (21.50 GMT).

The strongest earthquake of 3.3 degrees, occurred at 08.01 (14.01 GMT), said the SNET.

He added that the focal depth of earthquakes has fluctuated between 0.5 and 5.8 kilometers, so they felt in various parts of the city, near which is the San Salvador volcano, which is inactive.

Likewise, the eight earthquakes have reached an intensity of two on the Mercalli scale, whose maximum is 12, in San Salvador.

The Ministry of Environment and Natural Resources in a statement recalled that the last seismic swarm with epicenter in the San Salvador volcano was in 2007 when there were 142 microearthquakes, four of them felt by the population.

Apart from the string of earthquakes in San Salvador, today reported another quake Snet of 4.3 on the Richter scale at 11.26 local time (17.26 GMT) in Pacific Ocean, about 43 kilometers south of the estuary San Diego, in the department of La Libertad (center).

…(Univision)

March 23, 2012 Posted by | Seismic, Violence | , , , , , , , , | 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

# of Days Between Earthquakes Magnitude 7 or Higher from 2001 to Early 2012

Credit: QVS Data (http://qvsdata.wordpress.com/)

February 14, 2012 Posted by | Seismic | , , , , , , , | Leave a comment

How an Earthquake Warps a Landscape

A team of geologists from the U.S., Mexico and China are using light detection and ranging (LiDAR) laser altimetry to study how an earthquake can change a landscape. In particular, the geologists want to know more about the magnitude 7.2 quake that struck April 4, 2010, near Mexicali in northern Mexico. Airborne LiDAR equipment, which bounces a stream of laser pulses off the ground, can measure surface features to within a few centimeters. The researchers were able to make a detailed scan of the affected area over about 360 square kilometers in less than three days, they report in the February 10 issue of the journal Science.

In the above image, blue shows where ground surface moved down whereas red indicates upward movement compared with the previous survey.

LiDAR has a number of applications. Researchers have used it to study the properties of Saharan dust clouds for climate models as well as to gather detailed information on the plume emanating from Iceland’s Eyjafjallajökull volcano. Mexico had used LiDAR to map the Mexicali region in 2006, so Michael Oskin, a geology professor at the University of California, Davis, the paper’s lead author, and his colleagues had a baseline with which to compare their results.

Some changes brought about by the quake are readily visible from the ground, such as a 1.5-meter clifflike ridge created when part of a hillside abruptly moved up and sideways. But the LiDAR survey also revealed some features that could not easily be detected otherwise, Oskin reports, such as a warping of the ground surface above the Indiviso Fault, which runs beneath agricultural fields along the Colorado River floodplain.

The 2010 Mexicali earthquake did not occur on a major fault, such as the San Andreas, but rather ran through a series of smaller fractures in Earth’s crust. The new LiDAR survey shows how seven of these small faults came together to cause a major quake.

…(Scientific American)

February 11, 2012 Posted by | Science, Seismic | , , , , , , , , , , , , | Leave a comment

The 188 Day Earthquake Cycle – Revisited

On February 27, 2010, the first day of the cycle (2009 doesn’t check out).

There was a great 8.8 magnitude earthquake that struck offshore Maule, near Concepcion, Chile, at a depth of 30km, at approximately 06:34 UTC.

The segment of the fault zone which ruptured in this earthquake was estimated to be over 700 km long with a displacement of almost 10 meters. It lay immediately north of the 1,000 km segment which ruptured in the great earthquake of 1960.

A tsunami was produced with waves that struck Chile, the highest being 2.6m, New Zealand with surges up to 2.2m high. A low tsunami warning was issued for Alaska and Australia, with a partial evacuation of Easter Island for safety. A 4m wave struck Hiva Oa in the Marquesas Islands as well. Warnings were issued and cancelled for Hawaii and the Philippines.

Following were aftershocks, most at the same location, or a very close-distance away, from earliest to latest at 6.2, 6.0, 6.0, 6.9, 6.1, 6.0, 6.3 and 6.1, with dozens of 5-5.9 magnitude quakes, and a 6.2 magnitude quake near Salta, Argentina.

With over 500 killed and dozens missing, 370,000 destroyed homes in Chile, dismantled roads, buildings cracked in two, it is a day that is, and will be remembered by many for decades.

 

On September 03, 2010, the second day of the 188 day cycle, the first coincidental interval since the first date of February 27.

On this date there was a 6.3 magnitude quake at the Andreanof Islands of Alaska at 11:16 UTC. At approximately 16:35 UTC, a magnitude 7.0 earthquake struck with an epicenter near Darfield, Canterbury, New Zealand.

The quake caused widespread damage and power outages, particularly in the city of Christchurch, the second largest city.

The damage analysis of this earthquake differed from that of the Chile earthquake. It struck on land at a very shallow depth of 5km. The main quake occurred as a result of strike-slip faulting within the crust of the Pacific plate, near the eastern foothills of the Southern Alps at the western edge of the Canterbury Plains.

There were no reported casualties, but up to 100 people were injured. Aftershocks have continued into 2012, with some causing significant damage themselves. The quake caused up to 3.5 billion in damages and as of January, 2012, has had 9,300+ aftershocks of magnitude 2 or higher.

With images of buildings crumbling into the streets, the amount of people injured and the effect that the main quake has had on the land in the form of aftershocks since, this is definitely a significant event for that area that will surely be remembered for decades.

On March 11, 2011, the third day, and the second successful interval in the cycle of events following the two dates of February 27 and Sept 03. 188 days later following the afternoon events of September 3rd, 2010, to the early hours of March 11, 2011.

This day started dramatically, with one of the largest recorded earthquakes in recent history.

At approximately 05:46 UTC, a massive 9.0 magnitude earthquake struck on water at a depth of 22km near the east coast of Honshu, Japan.

There have since been over 1000 aftershocks recorded from the area. Following the 9.0 was a 7.9, 7.6 and dozens of aftershocks over 6.0.

This earthquake occurred where the Pacific Plate is subducting under the plate beneath northern Honshu; which plate is a matter of debate. The Pacific plate, which moves at a rate of 8 to 9 cm per year, dips under Honshu’s underlying plate releasing large amounts of energy. This motion pulls the upper plate down until the stress builds up enough to cause a seismic event. The break caused the sea floor to rise by several meters.

A quake of this magnitude usually has a rupture length of at least 480 km, and generally requires a long, straight fault surface. The plate in this area is not really straight. It was unusual for a quake here in exceed 8.5. The 9.0 was a surprise to most scientists.

The earthquake caused up to an 8 meter upthrust on a 180 km wide seabed at 60 km offshore from the east coast. A wave up to 38 meters was viewed at Omoe peninsula, Miyako city. Up to 11,000 miles away in Chile, waves as high as 2m came down. Russia evacuated up to 11,000 people from the Kuril Islands. In California and Oregon, following warnings, waves as high as 2.4 meters came down and caused up to 10 million $ US.

Warnings were issued all over the Pacific, homes were destroyed along parts of Indonesia, and the tsunami broke icebergs off the Sulzberger Ice Shelf in Antarctica about 8000 miles away.

The tsunami produced by the earthquake also took out the backup generators at the Fukushima I Dai’ichi power plant, leading to a frenzy and panic as fuel rods melted for weeks, months. It is the largest nuclear disaster since Chernobyl of Ukraine (SSR), in 1986. On the international nuclear event scale, with 7 being the highest, the disaster sat at level 4, then was raised to 5, and eventually level 7. Areas up to 50km away showed enough radiation to be concerned about. The country is still feeling the effects and will for some time.

The estimated cost from damages is said to be over 230 billion $ US. With a death toll said to be around 16,000 people, 6000 injured and over 3000 missing, with images of massive tsunami waves, fear and panic, and widespread devastation. It is a day that will be remembered for many years, the images never forgotten by many.

On September 15, 2011, the fourth day, and third date in the cycle of events, following the dates of February 27, September 03 and March 11. We arrive again, 188 days later.

At approximately 07:53 UTC, a 6.0 magnitude quake struck at a depth of 10km, east of North Island, New Zealand. At 08:00 exactly, a 6.2 quake struck near the east coast of Honshu, Japan, then at 19:31 UTC, a magnitude 7.3 earthquake struck in the Fiji region at a very deep depth of 630km.

The date wasn’t anything devastating this time, but still, a 7 magnitude or higher earthquake did strike, with a lot of other shaking going on around the globe. On the day prior, there was a lot of shaking in and around Greece and a 6.0 near the Aleutian Islands of Alaska. On the day following the 7.3 in Fiji, there was also a 6.7, 6.0 and a number of other aftershocks and tremors near the east coast of Honshu, Japan.

3 intervals of 188 days where regions of the globe release energy. An 8.8 was very significant on February 27, 2010, an 8.8 is closer to a 1/10 year event, where an 8.0 would be considered an annual event now. The first interval decided to glide from Chile to New Zealand for its 188 day anniversary. It was a large event that has left it’s scar. The second interval, New Zealand to Japan. The March 11, 2011 earthquake is described as being close to a 1/100 year event. It was the most powerful earthquake in known history to strike Japan, and one of the five most powerful earthquakes since 1900 when recording began.

The third interval of 188 days passed, but after a relatively slow few weeks of seismic activity, around and after the time-period of a few M and X class solar flares and geomagnetic storms. On the 15th, 188 days after the Japan earthquake, many said nothing would occur. For the third time, a 7 magnitude or higher earthquake did strike, while within the past 48 hours on that date, there were 4 other 6+ magnitude earthquakes.

Next is March 21, 2012, then September 25, 2012 and April 01, 2013.

February 7, 2012 Posted by | Seismic | , , , , , , , , , , , | 2 Comments

A New Way to Study Ground Fractures

Boise State University geophysics researchers have created a new way to study fractures by producing elastic waves, or vibrations, through using high-intensity light focused directly on the fracture itself. The new technique developed in the Physical Acoustics Lab at Boise State may help determine if there is a fluid, such as magma or water, or natural gas inside fractures in the Earth.

Typically, scientists create sound waves at the surface to listen for echoes from fractures in the ground, but this new technique could provide more accurate information about the cracks because sound does not have to travel to the fracture and back again. The new technique aims to enhance scientists’ abilities to image faults in the Earth, including those human-made through the process of hydraulic fracturing, or fracking.

The new method is explained in a paper that appears online in the journal Physical Review Letters.

“These concepts are of great importance in earthquake dynamics, but also in exploration of hydrocarbons,” said study coauthor Thomas Blum, a Boise State doctoral student. “If we can understand, for example, the microscopic structure of fracture points using this technique, we might be able to learn how, exactly, earthquakes happen. Scientists do not yet fully understand the structure of the faults, so if we could remotely sense the structure of faults, we might be able to learn more.”

Blum and Kasper van Wijk, associate professor of geosciences at Boise State, came up with the new technique by focusing laser light directly onto a fracture inside a transparent sample to create elastic waves. The researchers proved that laser-based ultrasonic techniques can “excite,” or cause vibrations, in the fracture. The result — jointly obtained with scientists at Colorado School of Mines and ConocoPhillips — opens up the possibility of measuring variations in the fracture and diagnosing the mechanical properties of fractures by directly exciting them.

…(Science Daily)

February 3, 2012 Posted by | Science, Seismic | , , , | Leave a comment

Obama Pushes Natural-Gas Fracking to Create 600,000 U.S. Jobs

Half of the quakes shown here (from the past week or so) are right beside fracking/drilling sites.

President Barack Obama pushed drilling for gas in shale rock and support for cleaner energy sources to boost the economy in his final State of the Union address before facing U.S. voters in November.

Hydraulic fracturing, the process of injecting water, sand and chemicals underground to free gas trapped in rock, could create more than 600,000 jobs by the end of the decade, Obama said yesterday. The process, called fracking, is among a list of energy policies Obama said would fuel economic growth.

“We have a supply of natural gas that can last America nearly 100 years, and my administration will take every possible action to safely develop this energy,” Obama said.

Obama reiterated support for conservation and cleaner sources of power and pledged more oil drilling as part of an ‘all-out, all-of-the-above” policy “that’s cleaner, cheaper, and full of new jobs.” He said domestic energy production is at an eight-year high and imports of foreign oil were declining, prompting criticism from Republicans.

“It’s just a blind accident, if in fact we are producing more oil or natural gas than in previous years, because it’s not because of any of his efforts,” Representative Darrell Issa, a California Republican and head of the House Oversight and Government Reform Committee, said after the speech.

…(SF Gate)

YouTube link to State of the Union address at the point of natural gas discussion.

Proposed Plan – Compare to the image to the left.

January 25, 2012 Posted by | Seismic | , , , , , , , | Leave a comment

Liquefaction Following Christchurch Earthquakes

December 24, 2011 – There is the possibility more areas of Christchurch could be red-zoned after yesterday’s strong earthquakes. Christchurch was rocked by two powerful tremors in quick succession yesterday afternoon, which forced evacuations from buildings. Since midnight there have been 23 aftershocks, with the last one just before 2.30pm. Many of today’s shakes were around magnitude 3, but the biggest, at 6:37am this morning, was magnitude 5.1. Most of the quakes were centred around the same area – off the coast, about 10 kilometres east of Christchurch.

The ongoing tremors mean many areas of Christchurch are still dangerous. The Port Hills pose a risk of rock falls, and authorities are urging people to steer clear, unless they live there. In the eastern suburbs, many residents are cleaning up liquefaction for the third, fourth or even fifth time this year. Parklands residents have said that they want their land rezoned red once and for all.

“We’ve had enough – we can’t keep doing this, this will happen again, and again,” said resident Geoff Cooke.

…(TVNZ)

December 24, 2011 Posted by | Seismic | , , | Leave a comment