Earthquakes

star gazer

Scientists complete mission to map fast-moving fault off Alaska (and Canada)

With a slip rate of more than 2 inches per year, this fault may be one of the fastest-moving strike-slip faults in the world. (For comparison, the San Andreas fault in central California slips about an inch to an inch-and-a-half each year.) Movement between the tectonic plates at the fault line has generated six earthquakes of magnitude 7 or greater within the last century. One of those earthquakes, a magnitude 7.8 earthquake near Lituya Bay, Alaska, in 1958 triggered a landslide that sent water 1,720 feet up an adjacent mountainside, one of the highest recorded runups of a tsunami — a rapidly rising turbulent surge of water often choked with debris.

Fathom

Remarkable movement between tectonic plates.

Fathom

Magnitude 4.4 earthquake 9 miles from Anza, CA · Aug 14, 6:24 PM

Fathom

Trump officials open door to fracking in California. Will fracking increase the number and severity of earthquakes in California?

star gazer

Another large Earthquake has shaken Lombok 6.3 magnitude.
A large Earthquake in Fiji. usgs 8.2 reading.

Fathom

Induced earthquakes (USGS): Seismicity can be induced at distances of 10 miles or more away from the injection point and at significantly greater depths than the injection point.

Black Swan

Fathom wrote: »

Trump officials open door to fracking in California. Will fracking increase the number and severity of earthquakes in California?

Makes me wonder to what extent Trump is advocating California fracking because they overwhelmingly voted against him by millions in 2016?

Fathom wrote: »

Induced earthquakes (USGS): Seismicity can be induced at distances of 10 miles or more away from the injection point and at significantly greater depths than the injection point.

Both fracking and deep wastewater pumping have been associated with earthquakes in the Midwest.

star gazer

There was a further 6.9 magnitude Earthquake impacting Lombok yesterday.

Fathom

Magnitude 4.4 earthquake 83 miles from Prudhoe Bay, AK · 2:33 AM

star gazer

7.3 Magnitude off the coast of Venezuela.

realitykeeper

Economic geography is even more interesting than physical geography in Venezuela today. Here are two videos, one showing an abundance of merchandise back in 2009 and another much more recent video showing mostly empty shelves.

https://www.youtube.com/watch?v=Hvx16uvSEJM

https://www.youtube.com/watch?v=ZJdAcS3SN-4

Fathom

Magnitude 6.2 earthquake 171 miles from Coos Bay, OR · Aug 22, 2:31 AM

Fathom

Magnitude 7.1 earthquake Affected countries: Brazil, Bolivia, and Peru 86 miles from Assis Brasil - State of Acre, Brazil · 2:04 AM

Fathom

Magnitude 6.0 earthquake 222 miles from Unalaska, AK · Aug 25, 9:50 AM

Fathom

Magnitude 5.6 earthquake Affected country: Antarctic 713 miles from Salvador, Falkland Islands (Islas Malvinas) · 1:09 PM

tabbey

realitykeeper wrote: »

Economic geography is even more interesting than physical geography in Venezuela today. Here are two videos, one showing an abundance of merchandise back in 2009 and another much more recent video showing mostly empty shelves.

https://www.youtube.com/watch?v=Hvx16uvSEJM

https://www.youtube.com/watch?v=ZJdAcS3SN-4

Seemed to be a lot of shoplifting in 2009.

Mod edit: The situation in Venezuela is dreadful, but not for discussion in this thread.

Fathom

Magnitude 4.4 earthquake 2 miles from La Verne, CA

Fathom

Magnitude 7.1 earthquake Affected countries: New Caledonia and Vanuatu 137 miles from New Caledonia · Aug 28, 8:51 PM

Fathom

Magnitude 6.6 earthquake shakes Sapporo

star gazer

Pictures on rte.ie from the 6.7 Japanese Earthquake. There are some very striking ones of landslides that were triggered. Sadly it's reported a number of homes were buried in the earthquake's aftermath. Japan has just this week had a Typhoon make landfall causing heavy flooding and wind damage with loss of life. They also had a severe heatwave this Summer.

7.8 South of Fiji, though it's depth was 600+km.

Fathom

star gazer wrote: »

7.8 South of Fiji, though it's depth was 600+km.

Wow!

Fathom

Today: 6.1 in San Pedro, Davao, Philippines 147 earthquakes in the past 24 hours

Fathom

Magnitude 5.8 earthquake 34 miles from Alto del Carmen, Chile · Sep 6, 7:39 PM

Fathom

Magnitude 6.9 earthquake 474 miles from Tauranga, New Zealand · Sep 9, 9:19 PM

Fathom

Magnitude 5.6 earthquake 34 miles from Yuxi, Yunnan, China · Sep 7, 7:31 PM

Fathom

Magnitude 5.4 earthquake 39 miles from Papua New Guinea · 3:32 PM

Fathom

Magnitude 5.6 earthquake 97 miles from Okinawa Prefecture, Japan · 1:05 AM Japan gets its share of earthquakes.

Fathom

Is Earthquake Activity Increasing?

Recent devastating earthquakes in Haiti, Chile and China, as well as magnitude 7 plus earthquakes in Indonesia and California, might give the impression that earthquake activity is increasing. In fact, a quick look at earthquake statistics over the last twenty years shows that this is not the case. On average there are about fifteen earthquakes every year with a magnitude of 7 or greater. As with any quasi-random phenomena, the number of earthquakes each year varies slightly from this average, but in general, there are no dramatic variations. So far this year, there have been six magnitude 7+ earthquakes, in keeping with the annual rate.

Fathom

Magnitude 7.5 earthquake 48 miles from Palu City, Central Sulawesi, Indonesia · 3:02 AM

Fathom

Fathom wrote: »

Magnitude 7.5 earthquake 48 miles from Palu City, Central Sulawesi, Indonesia · 3:02 AM

Indonesian Tsunami: Death Toll Hits 1,200.

Fathom

Magnitude 6.0 earthquake 272 miles from Petropavlovsk-Kamchatskiy, Russia · Oct 9, 12:45 AM

Fathom

Magnitude 3.8 earthquake 9 miles from Anza, CA · Nov 9, 6:58 AM

Fathom

Magnitude 6.3 earthquake 2005 miles from Punta Arenas, Chile · Nov 15, 3:09 PM

Fathom

Magnitude 6.3 earthquake Affected countries: Iran and Iraq 12 miles from Sarpol Zahab, Kermanshah Province, Iran · Nov 25, 8:37 AM

slowburner

Might be of interest...
https://www.nationalgeographic.com/science/2018/11/strange-earthquake-waves-rippled-around-world-earth-geology/?fbclid=IwAR0Zc4CAzwZPiOgt-OenBUgZjQiju5gR5bEdmG5TuuU9EV_BM08eZnFNagA

Fathom

slowburner wrote: »

Might be of interest...

Strange earthquake waves. Explanation?

Fathom

Magnitude 6.3 earthquake 2199 miles from Easter Island, Chile · Dec 12, 5:13 AM

Fathom

Magnitude 6.1 earthquake Affected countries: Indonesia and Papua New Guinea 77 miles from Pegunungan Bintang Regency, Papua, Indonesia · 1:42 AM

Fathom

Magnitude 5.6 earthquake 173 miles from Tual City, Maluku, Indonesia · Jan 3, 10:22 PM

Fathom

Has USGS affected by US Government shut-down for past 3 weeks?

Fathom

Magnitude 5.0 earthquake 9 miles from Anchorage, AK · Jan 13, 8:45 AM

Fathom

Magnitude 6.7 earthquake 9 miles from Coquimbo, Chile · Jan 19, 5:32 PM

Fathom

Magnitude 6.6 earthquake Affected countries: El Salvador, Guatemala, and Mexico 10 miles from Chiapas, Mexico · 8:14 AM

M5

Hi folks,

Was there any local seismic activity this morning at around 8am? in N Kildare/S Meath? I was in bed and the metal curtain rails and a few other bits in the room rattled/vibrated for about 10-15 seconds.

I would describe it as similar to a train passing by. I lived in the US, my apartment was about 50m away from a slow moving train and a similar level of vibration to that was what i felt this morning. Thing is we live miles away from the nearest busy road/train and are 100m away from the bohereen so truck/train etc are not likely

Fathom

Magnitude 1.5 County Donegal per Dublin Institute for Advanced Studies August 2017?

M5

Fathom wrote: »

Magnitude 1.5 County Donegal per Dublin Institute for Advanced Studies August 2017?

Hell of a delay on the aftershock :D

Probably another logical explanation or some minor local event. Very odd

Fathom

Magnitude 5.8 earthquake Affected countries: Peru and Ecuador 19 miles from Guayaquil, Ecuador · Feb 4, 9:45 AM

Fathom

Magnitude 6.2 earthquake 386 miles from Portugal · Feb 14, 11:57 AM

Conchir

I read an article recently on the Cascadia Fault in California and preparations for a possible future quake there. Really interesting article, I'd recommend it.

Anyway, in it they describe how researchers uncovered the last Cascadia quake, from 1700, with a really wide range of evidence. Pretty fascinating I think.

In the late nineteen-eighties, Brian Atwater, a geologist with the United States Geological Survey, and a graduate student named David Yamaguchi found the answer, and another major clue in the Cascadia puzzle. Their discovery is best illustrated in a place called the ghost forest, a grove of western red cedars on the banks of the Copalis River, near the Washington coast. When I paddled out to it last summer, with Atwater and Yamaguchi, it was easy to see how it got its name. The cedars are spread out across a low salt marsh on a wide northern bend in the river, long dead but still standing. Leafless, branchless, barkless, they are reduced to their trunks and worn to a smooth silver-gray, as if they had always carried their own tombstones inside them.

What killed the trees in the ghost forest was saltwater. It had long been assumed that they died slowly, as the sea level around them gradually rose and submerged their roots. But, by 1987, Atwater, who had found in soil layers evidence of sudden land subsidence along the Washington coast, suspected that that was backward—that the trees had died quickly when the ground beneath them plummeted. To find out, he teamed up with Yamaguchi, a specialist in dendrochronology, the study of growth-ring patterns in trees. Yamaguchi took samples of the cedars and found that they had died simultaneously: in tree after tree, the final rings dated to the summer of 1699. Since trees do not grow in the winter, he and Atwater concluded that sometime between August of 1699 and May of 1700 an earthquake had caused the land to drop and killed the cedars. That time frame predated by more than a hundred years the written history of the Pacific Northwest—and so, by rights, the detective story should have ended there.

But it did not. If you travel five thousand miles due west from the ghost forest, you reach the northeast coast of Japan. As the events of 2011 made clear, that coast is vulnerable to tsunamis, and the Japanese have kept track of them since at least 599 A.D. In that fourteen-hundred-year history, one incident has long stood out for its strangeness. On the eighth day of the twelfth month of the twelfth year of the Genroku era, a six-hundred-mile-long wave struck the coast, levelling homes, breaching a castle moat, and causing an accident at sea. The Japanese understood that tsunamis were the result of earthquakes, yet no one felt the ground shake before the Genroku event. The wave had no discernible origin. When scientists began studying it, they called it an orphan tsunami.

Finally, in a 1996 article in Nature, a seismologist named Kenji Satake and three colleagues, drawing on the work of Atwater and Yamaguchi, matched that orphan to its parent—and thereby filled in the blanks in the Cascadia story with uncanny specificity. At approximately nine o’ clock at night on January 26, 1700, a magnitude-9.0 earthquake struck the Pacific Northwest, causing sudden land subsidence, drowning coastal forests, and, out in the ocean, lifting up a wave half the length of a continent. It took roughly fifteen minutes for the Eastern half of that wave to strike the Northwest coast. It took ten hours for the other half to cross the ocean. It reached Japan on January 27, 1700: by the local calendar, the eighth day of the twelfth month of the twelfth year of Genroku.

Really good display of different disciplines combining to reconstruct environmental history. The Cascadia fault is 319 years into a 243 year recurrence interval, so a big one is predicted by some geologists, according to the article.

https://www.newyorker.com/magazine/2015/07/20/the-really-big-one

Fathom

Anything 8.0 or over will toast Los Angeles. Said the Big One is coming. But in geological time. Tomorrow or hundreds of years from now. Just a blink of the eye.