Earthquakes and Volcanic eruptions have always been closely related. For instance, if you look at a map of quakes worldwide and compare it to a map of volcanoes, you’ll find that they match closely.
Both earthquakes and volcanoes occur at the boundaries of tectonic plates, which make up the Earth’s surface. Earthquakes are caused by the release of pressure built up when the plates spread apart or move past each or under each other.
In slightly more complicated ways, magma is generated at most plate boundaries, and this magma rises to the surface to form volcanoes. In recent weeks, earthquakes have exponentially increased in magnitude worldwide, worrying some researchers as they provide the fuse that ignites volcanoes.
The movement of magma within a volcano causes earthquakes, usually small ones. Earthquakes are also caused by adjustments to the flanks of volcanoes and the plates under volcanoes.
For decades, a source of powerful earthquakes and volcanic activity on the Pacific Rim was shrouded in secrecy, as the Soviet government kept outsiders away from what is now referred to as the Russian Far East.
In the last 20 years research has shown that the Kamchatka Peninsula and Kuril Islands are a seismic and volcanic hotbed, with a potential to trigger tsunamis that pose a risk to the rest of the Pacific Basin.
A magnitude 9 earthquake in that region in 1952 caused significant damage elsewhere on the Pacific Rim, and even less-powerful quakes have had effects throughout the Pacific Basin.
“There’s not a large population in the Russian Far East, but it’s obviously important to the people who live there. Thousands of people were killed in tsunamis because of the earthquake in 1952.
Earthquakes greater than magnitude 8 struck the central Kurils in 2006 and 2007, and both produced large local tsunamis, up to about 50 feet. Though the tsunamis that crossed the Pacific were much smaller, the one from the 2006 quake did more than $10 million in damage at Crescent City, Calif.
In 2009, Sarychev Peak in the Kurils erupted spectacularly, disrupting air traffic over the North Pacific.
Clearly, determining the frequency of such events is important to many people over a broad area, Bourgeois said.
“Let’s say you decide to build a nuclear power plant in Crescent City. You have to consider local events, but you also have to consider non-local events, worst-case scenarios, which includes tsunamis coming across the Pacific,” she said.
But that is only possible by understanding the nature of the hazards, and the historic record for earthquakes, tsunamis and volcanic eruptions in Kamchatka and the Kurils is relatively short.
In addition, because the region was closed off from much of the world for decades, much of the information has started becoming available only recently.
Much has been learned in the last 10 years in the examination of tsunami deposits and other evidence of prehistoric events, but more field work in the Kamchatka-Kurils subduction zone is required to get a clearer picture.
For hazard analysis, you should just assume that a subduction zone can produce a magnitude 9 earthquake.
So it is important to “pay attention to the prehistoric record” to know where, and how often, such major events occur.
It has been noted that in the last 25 years research in the Cascadia subduction zone off the coast of Washington, Oregon, northern California and British Columbia has demonstrated that the historic record does not provide a good characterization of the hazard.
It was once assumed the risks in the Northwest were small, but the research has shown that, before there were any written records, Cascadia produced at least one magnitude 9 earthquake and a tsunami that struck Japan.
Alaska’s Aleutian Islands and the Komandorsky Islands, an extension of the Aleutians controlled by Russia, are another source of seismic and volcanic activity that need to be evaluated for their potential risk beyond what is known from the historical record.
“The Aleutians are under-studied,” Bourgeois said. “The work in the Russian Far East is kind of a template for the Aleutians.”
Ideally, a dedicated boat could ferry researchers to a number of islands in the Aleutian chain, similar to how Bourgeois and other scientists from the United States, Japan and Russia have carried out a detailed research project in the Kuril Islands in the last decade.
Over the last couple of years researchers have gradually shifted from the decades old belief that asteroids killed the dinosaurs. As a former college history professor, I can confirm that almost all text books claim dinosaurs were killed 65-million-years ago by an asteroid slamming into the earth.
Today, research suggests that tens of thousands of years of lava flow from the Deccan Traps, a volcanic region near Mumbai may have spewed poisonous levels of sulphur and carbon dioxide into the atmosphere and caused the mass extinction through the resulting global warming and ocean acidification.
The findings are the latest volley in an ongoing debate over whether an asteroid or volcanism killed off the dinosaurs in the mass die-off known as the K-T extinction, the ‘Live Science’ reported.
Proponents of the old hypothesis argue that a giant meteorite impact at Chicxulub, Mexico, around 65 million years ago released toxic amounts of dust and gas into the atmosphere, blocking out the Sun to cause widespread cooling, choking the dinosaurs and poisoning sea life.
The further point out that the meteorite impact may also have set off volcanic activity, earthquakes and tsunamis.
In 2009, oil companies drilling off the Eastern coast of India uncovered eons-old lava-filled sediments buried nearly 3.3 kilometers below the ocean surface. They contained plentiful fossils from around the boundary between the Cretaceous-Tertiary periods, or K-T Boundary, when dinosaurs vanished.
The sediments bore layers of lava that had travelled nearly 1,603 km from the Deccan Traps.
The volcanic region, today, spans an area as big as France, but was nearly the area of Europe when it was active during the late Cretaceous period, said Adatte Thierry, a geologist from the University of Lausanne in France.
The idea that volcanic eruption may have terminated life on earth for the dinosaur, simply wakes you up when you consider the true danger an eruption poses to civilization. It’s even more daunting when you grasp the fact that earthquakes are essentially the fuse that sets them off.
In recent weeks, worldwide earthquake data indicates an increase in the magnitude and a significant increase in the frequency (magnitude > 5.5) of earthquakes.
Current graphs clearly show an alarming worldwide trend of increasing earthquake strength and frequency. These results are in agreement with the USGS statistics page, which shows an increase in the frequency of stronger earthquakes (M > 5.0).
These trends also show that the depth of earthquakes has diminished, they occur closer to the Earth’s surface. Shallow earthquakes occur along fault lines and are due to the accumulation of stress. Earthquake waves can also propagate far enough to trigger other earthquakes; this may explain the noted increase in earthquakes.
Certain scientists have stated that the increased frequency of earthquakes is due to the increased number of detection instruments installed worldwide. This would cause more sensitive earthquakes to be measured. However, these graphs show an increase in stronger earthquakes; it is also important to note that the earthquake Richter scale is base-10 logarithmic.
The fact that the world’s population has increased doesn’t help, more people are affected by these events.
There is increased media availability and attention. However, due to recent events, it is now easy to convince even the average person, that there are more and more strong earthquakes occurring worldwide:
A Yellowstone National Park earthquake in Wyoming was felt in sections of Montana and Idaho. The Wyoming earthquake, which occurred on December 15, 2012 was centered in the northwest corner of the state. Though there were no reports of damage we must remember Yellowstone Caldera is located in the northwest corner of Wyoming.
Here’s the history lesson. Yellowstone lies over a hotspot of molten mantle rock that occasionally rises towards the surface.
Over the past 18 million years, Yellowstone has generated a succession of violent eruptions; some of them have been classified as supereruptions.
Volcanic eruptions can empty their storage of magma so quickly that they can cause the superimposing land to collapse into a magma chamber, forming a geographic depression called a caldera. I’m talking about a lake the size of the state of Texas and perhaps that estimation is significantly under estimated.
Yellowstone Caldera is called a Supervolcano because it’s able to produce extraordinarily huge volcanic explosions.
Because of the volcanic and tectonic nature of the region, the Caldera experiences somewhere between 1000 and 2000 earthquakes a year.
The last supereruption on the Yellowstone volcano occurred approximately 640,000 years ago. The event ejected more than 240 cubic miles of volcanic ash into the sky and across the plain.
On Saturday December 15, 2012, shortly after 12:25 p.m. local time, a light earthquake stuck Yellowstone National Park in Wyoming. The quake, however, had nominal depth. Officials say the quake was only six miles below the earth’s surface. As a result, the quake could be felt across the region.
USGS indicates that the quake erupted twenty-five miles south of Cooke City-Silver Gate, Montana. The quake was also forty-four miles southeast of Gardiner, Montana. Officials tell news the quake was forty-seven miles west of Cody, Wyoming and roughly two hundred eighty miles north of Salt Lake City, Utah.
As I mentioned earlier, quakes visit the area frequently, without causing major alarm. Nevertheless, the Yellowstone Supervolcano is amongst the largest in recorded world history, thus it poses a threat of considerable proportions. Most researchers claim that if it erupted today, it would come close the obliterating the entire land area known as the United States. In addition, it would likely have an enormous consequences on world weather, agriculture and quality of life.
There are an estimated 1,500 active volcanoes around the world, 50 to 60 erupt every year, spewing steam, ash, gas and lava. These reflectively, mild outburst don’t come close to the dangers Yellowstone present. The fact is, if it were ever to erupt, it would only take moments to end the life of everyone in close proximity. If you like in the USA, the idea of escaping its reach is borderline fantasy. In other words, it would be practically impossible. One can only hope that it doesn’t blow in our lifetime; but it is certain to erupt in someone’s lifetime.
All it takes is a few well placed earthquakes for it to blow.
Technology certainly has its hands full.
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