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96232
From: pamela, [DNS_Address]
Subject: Lowel Whiteside summary of 6.0 N Pacific quake
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((what is not reported is there was a quake in 1927 off the S Calif coast and wikipedia link shows it here, stating it was off Lompoc, Calif, but no mention of the Murray fracture zone--Pamela notes)) https://en.wikipedia.org/wiki/1927_Lompoc_earthquake Lowel posts his summary here:(see link) UNPRECEDENTED M 6.0 IN NORTH PACIFIC 1200 KM WEST OF CALIFORNIA EARTHQUAKE SUMMARY FOR NOVEMBER 1, 2022 The strongest earthquake in the world today was an M 6.0 in the North Pacific Ocean about 1250 km west of San Diego and Los Angeles, California. NEIC reported it was felt lightly in California throughout the coast in areas from San Francisco to Washington State to southern California. This is an unprecedented earthquake in the middle of the North Pacific. There is no reason to expect earthquakes such as this in this region of the Pacific as no tectonics would support this. It is possible this was a meteor impact in the ocean, but this cannot be confirmed. If this is a tectonic earthquake it could indicate regional stress is high and could indicate a strong earthquake along the coast of California could be nearer than previously thought. A strong earthquake of M 7.5 hit off the coast of Baja California, Mexico a week before the M 8.3 in San Francisco, California in April 1906. This is concerning as there was an M 5.1 in San Francisco on October 25, 2022. Today's earthquake is the strongest ever recorded within about 500-1000 km of this epicenter in the North Pacific and as such is very significant. The felt area along the west coast of North America is also unusual. EMSC reported an M 3.8 in Central California three minutes after the M 6.0 in the North Pacific, but ANSS does not list this earthquake so it is probably a ghost quake due to seismic waves from the North Pacific arriving in California at that time. This event is located at the fourth node (90 degrees) from recent strong earthquakes in Taiwan (including today's M 5.7) and Luzon, Philippines and is also located at this distance from TS Nalgae currently east of the Philippines. It is also at the seventh node (52 degrees) from the M 6.8 south of Panama of October 20, 2022. O: 2NOV2022 04:53:14 31.6N 133.3W Mw=6.0 EMSC NORTH PACIFIC OCEAN Other earthquakes in the oceanic regimes today included a pair of moderate quakes of M 4.8 and 4.9 southeast of Easter Island and an M 4.5 in the Northern Mid-Atlantic Ridge. The activity in the area south of Easter Island follows a moderately strong quake north of this yesterday of M 5.8. At the time this summary noted: "The strongest earthquake in the world today was an M 5.8-6.0 in the West Chile Rise. It was not reported felt in this remote area. This is the strongest earthquake within about 250 km of this epicenter since an M 5.9 on May 20, 2010. The only other such event in the area in the past 30 years was an M 5.8-6.0 on June 5, 2008. Forecast 148090 had expected this activity in this region was likely in early, November, 2022. This epicenter is at 144 degrees from the M 7.0 in Luzon, Philippines of July 27, 2022 and the subsequent M 6.4 in late October. It is likely it was promoted by energy from that source." (November 1, 2022) Forecast 148090 had expected this activity within about 25 km was likely in early November. This activity is at 144 degrees from Taiwan where an M 6.9 occurred on September 18, 2022 as well as from Luzon and at the sixth node (60 degrees) from the M 7.6 in Michoacan, Mexico of September 19, 2022 and was probably promoted by energy from these sources. |
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96246
From: sher, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
URL: https://earthquake.usgs.gov/earthquakes/eventpage/us7000imgl/executive
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And there was the large shallow quake in Baja California yesterday. So maybe a heads up? |
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96250
From: Eve, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Lowell's summary of November 4th is what I was waiting for (especially after I saw a report of a house caught on fire in NorCal late Friday seems to connect to a meteorite). -->Video shows fireball in Northern California sky from possible meteor: https://www.youtube.com/watch?v=_99GbxFDnFc -->Investigation into possible meteorite landing on NorCal home: https://www.youtube.com/watch?v=oOn3oVKc_Sg&t=38s Links here with info on Taurid Meteor showers (fwiw I have seen Taurid meteor years ago they are large and not as fast moving as others like Geminid meteors): ->November Southern Taurids meteor shower will feature bright fireballs: http://earthboppin.net/talkshop/space/messages/46954.html -November Southern Taurids meteor shower all you need to know http://earthboppin.net/talkshop/space/messages/46955.html ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- EXCERPT: STRONG QUAKE SHAKES NORTHERN GULF OF CALIFORNIA EARTHQUAKE SUMMARY FOR NOVEMBER 4, 2022 The strongest earthquake in the world today was an M 6.1-6.2 in the northern Gulf of California. NEIC reported it was felt in Sonora, Mexico with intensity IV in Bahia de Kino, Guaymas and in San Luis, Baja California, Mexico. Intensity II-III was reported in Sonora at Hermosillo, Obregon, Nogales and in Guerrero Negro, Baja California, Mexico. Earthquakes in this area can stress faults to the north in Southern California, leading to enhanced seismicity in that area. A series of moderate foreshocks have hit this area in the past several days leading to today's mainshock. These included an M 4.1 and 4.2 on November 1 and 2, 2022. The last earthquake within about 200 km of this epicenter with M>=6 was an M 7.0 ten years ago on April 12, 2012. At the time this summary noted in this regard: "The earthquake of M 6.9-7.1 in the Gulf of California is the strongest to occur in this region of the Gulf in at least 22 years. A slightly smaller event hit the region on August 3, 2009 with M 6.8-6.9." (April 12, 2012) That event was part of a major seismic spasm which included an M 8.6 in Sumarta an M 7.4 in Guerrero, Mexico and moderate quakes in the Tokyo area of Japan among others. A strong M 6.1 also occurred two days ago in the Pacific Ocean about 1200 km west of the Gulf of California and California in general at the time this summary noted in this regard: "... It is possible this was a meteor impact in the ocean, but this cannot be confirmed. If this is a tectonic earthquake it could indicate regional stress is high and could indicate a strong earthquake along the coast of California could be nearer than previously thought. A strong earthquake of M 7.5 hit off the coast of Baja California, Mexico a week before the M 8.3 in San Francisco, California in April 1906. This is concerning as there was an M 5.1 in San Francisco on October 25, 2022." (November 2, 2022) |
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96251
From: ryan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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"It is possible this was a meteor impact in the ocean" i wonder how big a meteor has to be to create a tsunami... |
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96254
From: Eve, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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hi ryan, When I read your question the first thing that came to mind was the event in Russia that felled a forest. https://en.wikipedia.org/wiki/Tunguska_event Then next I did a query concerning the topic of meteorite size and ocean and asteroid reference also came up: --How big would a tsunami be if an asteroid hit the ocean? A 250 meter asteroid would result in less than a a 10 meter high tsunami after 60 km of travel, a 500 meter asteroid would result in a 100 meter high wave after 30 km of travel and in a 10 meter high tsunami after 200 km of travel, a 1 km diameter asteroid would run 80 km before the tsunami wave amplitude was less than ... Asteroid Tsunami Wave Heights | Download Table - ResearchGate https://www.researchgate.net › figure › Asteroid-Tsunami-... + The followin text is from International Tsunami Information Center: --Can asteroids, meteorites or man-made explosions cause tsunamis? Fortunately, for mankind, it is indeed very rare for a meteorite or an asteroid to reach the earth. Although no documented tsunami has ever been generated by an asteroid impact, the effects of such an event would be disastrous. Most meteorites burn as they reach the earth's atmosphere. However, large meteorites have hit the earth's surface in the distant past. This is indicated by large craters, which have been found in different parts of the earth. Also, it is possible that an asteroid may have fallen on the earth in prehistoric times - the last one some 65 million years ago during the Cretaceous period. Since evidence of the fall of meteorites and asteroids on earth exists, we must conclude that they have fallen also in the oceans and seas of the earth, particularly since four fifths of our planet is covered by water. The fall of meteorites or asteroids in the earth's oceans has the potential of generating tsunamis of cataclysmic proportions. Scientists studying this possibility have concluded that the impact of moderately large asteroid, 5-6 km in diameter, in the middle of the large ocean basin such as the Atlantic Ocean, would produce a tsunami that would travel all the way to the Appalachian Mountains in the upper two-thirds of the United States. On both sides of the Atlantic, coastal cities would be washed out by such a tsunami. An asteroid 5-6 kilometers in diameter impacting between the Hawaiian Islands and the West Coast of North America, would produce a tsunami which would wash out the coastal cities on the West coasts of Canada, U.S. and Mexico and would cover most of the inhabited coastal areas of the Hawaiian islands. Conceivably tsunami waves can also be generated from very large nuclear explosions. However, no tsunami of any significance has ever resulted from the testing of nuclear weapons in the past. Furthermore, such testing is presently prohibited by international treaty. Click the link below to view a movie that shows a physics-based computer simulation of the tsunami generated by the impact of the Chicxulub asteroid 65 million years ago. This asteroid impact is thought to responsible for the extinction of the dinosaurs. https://youtu.be/Dcp0JhwNgmE + Excerpt: --Why do meteorites cause tsunamis? Image result for a meteorite the size of the one that hit tungsta could cause a tsunami Depending on the impact energy and the depth of the ocean, a large amount of water is displaced, forming a temporary crater in the water column. Large tsunami-like waves originate from the collapse of the cavity in the water and the ejecta splash.Oct 28, 2015 The meteorite impact-induced tsunami hazard - Journals https://royalsocietypublishing.org/doi/10.1098/rsta.2014.0381 |
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96255
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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re: 6.0 mag quake in no. pacific. "If" a meteor cause this quake, it would have had to penetrate to the ocean floor. It would not have been an air burst. "If" a meteor big enough to penetrate the deep ocean and hit the floor to cause such a quake, then it most certainly should create some sort of tsunami. A meteor capable of connecting with the actual ocean floor and creating a quake of that size would have to be pretty massive..most certainly of iron/nickel make up, or it would have airburst..not causing an earthquake (but certainly atmospheric waves that would have been detected through out the globe as in past airblasts). Yet..the seismos picked up a "bang" at the beginning of the p waves. So, if it wasn't a meteor..what was it? brought back to methane explosions, unknown/to this time undiscovered volcanic activity as the most likely causes (but cannot verify either with existing, public data yet). Just ruling things out. If you remove all the things it could not be, eventually you will be left with what it is..as unlikely as "what it is" might be. (Paraphrasing Sherlock Holmes here lol). It is a puzzlement (Yul Brenner in "The King and I") |
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96260
From: jordan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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could it be a metor, there was a possible house fire from one in California this past week. |
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96257
From: ryan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
| that was my thought also...if it was big enough to get to the ocean floor if seemingly would have generated a tsunami, which it did not...puzzling for sure...maybe it is the first crack in a new rift zone... |
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96258
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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could be...that's unlikely, but not ruled out. Very cold, stable floor there. They're "shouldn't" be a ridge there, or volcanics..it would have to be a baby new one. Stranger things have been discovered though, so not removed from the list of "could be"s. That being said, nature is weird and loves nothing more than screwing with human scientists LOL. |
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96259
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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what I would like to see is that new satellite data to se if there's a new methane plume in that area. Until I find data that says "no", methane explosion is still on the board as a theory. |
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96262
From: jordan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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The focal mechanism is strike-slip, suggesting it could have happened on a fossil fracture zone - a place that had earthquakes back when this was actively growing, and therefore has residual weakness. The Pacific–North America Plate boundary motion today is concentrated on continental fault systems well to the east, and this region of oceanic crust is generally thought to be within the rigid Pacific Plate. Yet, the 2012 December 14 Mw 6.3 earthquake that occurred about 275 km west of Ensenada, Baja California, Mexico, is evidence for continued tectonism in this oceanic part of the Pacific Plate. The preferred main shock centroid depth of 20 km was located close to the bottom of the seismogenic thickness of the young oceanic lithosphere. The focal mechanism, derived from both teleseismic P- wave inversion and W-phase analysis of the main shock waveforms, and the 12 aftershocks of M ∼3–4 are consistent with normal faulting on northeast striking nodal planes, which align with surface mapped extensional tectonic trends such as volcanic features in the region. Previous Global Positioning System (GPS) measurements on offshore islands in the California Continental Borderland had detected some distributed Pacific and North America relative plate motion strain that could extend into the epicentral region. The release of this lithospheric strain along existing zones of weakness is a more likely cause of this seismicity than current thermal the quake occurred in the middle of a large plate — a phenomenon known as an “intraplate earthquakes https://en.wikipedia.org/wiki/2012_Indian_Ocean_earthqu akes |
96265
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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normal faulting... this is when a block drops down, while blocks on the side move up or out. Same thing I saw on there. It is possible there's an old structure out there that, while not really active now--was at some point millions of years ago and left dormant and weakened causing a quake. Pretty big for a dorant..would have to be something like an ancient ridge to create a quake of this type (rather than other types of fault structures). Or, a new structure...emerging structure being born. An issue with this theory, however, is the anomolous P wave signature..with the bang at the beginning. Like something exploded/went bang kicking off the event. Also, if you have a big enough drop of a block, you should see a ripple in the buoy levels (small at a 6.0, but should be there as a drop of a block would cause vertical displacement). Yet..none reported. This quake is still very weird and now occupies a small corner of my head lol. |
96268
From: jordan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
| could the depth of the ocean distort the p wave |
96269
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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possibly--but it was picked up on a bunch of seismos. That's one of the reasons I wrote to a seismologist about it. Lowell Whiteside also seemed to feel it might be some sort of explosive event (his theory was perhaps a meteor). |
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96271
From: ryan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
| maybe an errant kim chee missle... |
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96261
From: jordan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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volcanic new activity related to the Murray Fracture Zone? one never knows what is historic they have been only recording quakes since early 1900's and there could be aftershocks but too small to detect on land. |
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96264
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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well, "associated" is a broad term. The Murray zone is at least 100 mi north of there...it's a transition fault (side to side, vertical fault) rather than a subduction type (over under), so it's "unlikely" that this particular fault would be responsible for either quake or volcanics that far south. The moment tensor, also...shows a "pushing out" action, with two sides pushing apart rather than past each other. You might see this in an expansion motion (ridge pushing apart or an explosion of some sort pushing two sides apart). Right on the lack of aftershocks..that far out, the small ones wouldn't be picked up, only large ones. So all this tells us is there's been non large aftershocks. |
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96256
From: Eve, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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"Iffy" stuff happens. |
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96252
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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If a meteor was big enough to create a 6.0 quake, it would be plenty big enough to create surface waves on the ocean. Let's put it this way--the meteor that hit that house in No. Calif? It didn't even create a quake. To create a 6.0 quake..we are talking massive. We're talking then in the range of tunguska event size (12 megaton exosions on scale with large nuclear weapon size) Mind you, all that damage to the man's house was probably from something the size of a baseball when it reached the ground. Then there is the air bursting bolide that more recently blew up just above the ground in Russia: "The Chelyabinsk meteor was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately 20 m (66 ft) near-Earth asteroid that entered the atmosphere at a shallow 18.3 ± 0.4 degree angle with a speed relative to Earth of 19.16 ± 0.15 kilometres per second (69,000 km/h or 42,690 mph).[6][7] The light from the meteor was briefly brighter than the Sun, visible up to 100 km (62 mi) away. It was observed over a wide area of the region and in neighbouring republics. Some eyewitnesses also felt intense heat from the fireball. The object exploded in a meteor air burst over Chelyabinsk Oblast, at a height of around 29.7 km (18.5 mi; 97,000 ft).[7][8] The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to 26.2 km (16.3 mi), and many surviving small fragmentary meteorites. The bulk of the object's energy was absorbed by the atmosphere, creating a large shock wave with a total kinetic energy before atmospheric impact estimated from infrasound and seismic measurements to be equivalent to the blast yield of 400–500 kilotons of TNT (about 1.4–1.8 PJ) range – 26 to 33 times as much energy as that released from the atomic bomb detonated at Hiroshima,[9] and the rough equivalent in energy output to the former Soviet Union's own mid-August 1953 initial attempt at a thermonuclear device...." "..incoming celestial objects have rapid directional motion, the object causes stronger blast wave and thermal radiation pulses at the ground surface than would be predicted by a stationary object exploding, limited to the height at which the blast was initiated- where the object's "momentum is ignored".[59] Thus, a meteor airburst of a given energy is "much more damaging than an equivalent [energy] nuclear explosion at the same altitude".[60][61] The seismic wave produced when the primary airburst's blast struck the ground yields a rather uncertain "best estimate" of 430 kilotons (momentum ignored),[61] corresponding to the seismic wave which registered on seismographs at magnitude 2.7.[42][43][44]..." https://en.wikipedia.org/wiki/Chelyabinsk_meteor Many here will remember the damage that cause and it didn't even hit the ground, but blew up above it (then pieces fell). All this is why...when the recent 6.0 "odd" quake in the ocean hit, I'm more and more convinced it was not a meteor because: to cause a quake that size it would have had to be big enough to penetrate the deep ocean and actually hit the sea floor. And second, there's non way something of that size hitting the ocean wouldn't have set off bouys all around from the massive ripples (tsunami) it would have caused. Add to that the monitors they talk about above would have tracked something that large and explosive coming in...even above the ocean. They might miss meteors the size of the one that hit that unfortunate couple's house..but they would have definitely picked up something as large to create a 6.0 quake on the sea floor for fear of some rogue country setting off a nuke or nuke test. Eve..I took a look at the no. California "Gulf" quake, and all the data looks consistant with a run-of-the- mill transform fault off the spreading ridge. Nothing pecular there like the one that was out in the no. Pacific that had the strange data with it. I don't think these three events are related at this point...that's not to say a meteor hitting a house isn't pretty spectacular, but unless I see any additional data --these seem (at least at this time) to be three different things going on. Meteor hitting house Regular transition quake that happen often in Gulf of Calif. Weird ass quake in pacific ocean with weird ass accompanying data set...leaning toward a volcanic or even methane explosion event (but cannot verify or eliminate other causes). This quake would make some university student a kick-ass doctorate project. |
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96253
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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btw, I'm most upset about that no. calif man's poor dog!!! |
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96238
From: Eve, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
URL: http://earthboppin.net/talkshop/geology/messages/96230.html
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Thank you much pamela. Meteor was what came to me also even though I don't know much about it. I can only say I had heavy incoming feels for something and have extra sensors when it comes to sky/air events and felt some release about the same time of this 6.0 eq. (posted in regards to such on groans board). |
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96241
From: pamela, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 thanks Evie for your feedback(NT)
| (NT) |
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96233
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Okay...I feel better. I was trying to figure this one out for sure. My daughter had texted me asking me about it and the more I looked at the data, the more puzzled I was. many of the seismograms showed some sort of elevated beginning wave..like this quake was started by a sudden event (a boom of some sort). The moment tensor showed possible expansion movement (like you would see in either an explosion or sudden movement apart)...the motion moving away from the center. Not unheard of, but very odd. You might see a signature like that in a down dropping block at a spreading ridge...but there is no ridge there (that we know of). Meteor was on the list of possiblities, but the thing that is inconsistant is there was no rise in the surrounding buoy levels. To have an extraterrestrial hit that large to make a 6.0 mag quake, one would expect some rise around an impact area (displacement of water and corresponding tsunami of some sort). No fireball reports either. That could be because it was so far at sea, but I don't think it was so far that an extremely large meteor--as this would have to be, wouldn't have been sighted by anyone near the coasts or in the shipping lanes, or tracked by radar in our defense systems. But..if it's not that..what is it? Other possibilities (that I can not verify or rule out).. manmade projectile...Korea has been setting off long range missiles, some just before this event. Could one have gotten that far? To make a seismic signature of that strength, it would almost have to have been nuclear armed. No radiation detections have been picked up as far as I know. Or an illegal nuclear test..but usually, that's picked up quite quickly by the many countries around the world who monitor signatures for such things. Even if one country attempted to hide that info, there's always several countries that announce it anyway (hard to keep those secret after the fact). Undiscovered undersea volcanics...there "shouldn't" be any at that point on the sea floor, but science has been surprised before. Methane explosion: lots of methane in the sea floor and it's possible a pocket exploded-- nuclear sub accident: scenario of a nuclear submarine having an issue..sinking so far down the pressures explode it, including whatever weaponry was onboard. Some of these are more likely than others. Nuclear suggestions would have to be verified by escaped radiation around the site of the quake. All this being said, it's nice to know that the experts are as flumoxed as the rest of us who are armchair scientist watchers. Thanks for posting this, Pamela I sent an email out to a seismologist as well, but have not heard back from them yet. |
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From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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This is the seismologist I wrote to..while she hasn't responded to me, she seems to have responded to the LA times: A 6.0 magnitude earthquake was recorded almost 800 miles off the Southern California coast Tuesday night, an “oddball” event that made little impact but drew intrigue from scientists because of its location. “It’s a decent size, but that’s a location that is just not common,” said Susan Hough, a seismologist with the U.S. Geological Survey in Pasadena. “I’ve been watching earthquakes for going on 40 years, and I don’t remember anything that big in that location.” The temblor occurred roughly in line with San Diego. Since 1900, there have been only 10 other recorded earthquakes in the north Pacific Ocean off Southern California’s coast — and of the temblors more than 500 miles from the coast, all measured under 5.0 magnitude, according to the USGS. Tuesday’s earthquake occurred just before 10 p.m., and as of Wednesday morning, no aftershocks had been recorded, Hough said. She said because of its location, the seismic activity is unlikely to have caused any damage or had any other effects, though she said nearby boats could have felt the movement. he earthquake’s location is considered odd because it did not fall near or along tectonic plate boundaries, but in the middle of a large plate — a phenomenon known as an “intraplate earthquake,” Hough said. The vast majority of earthquakes occur along plate boundaries, like along California’s San Andreas fault, though intraplate earthquakes do sometimes occur. “It’s a weird earthquake,” Hough said. “There really isn’t an overarching explanation for intraplate earthquakes, except that they happen.” She called the earth’s plates “fairly stable,” as they don’t have major fault lines that shift or move, but she said stress can occur mid-plate, such as the cooling of oceanic crust as it ages. “There’s stresses in the crust for all sorts of reasons, so you can have these oddball events that pop up,” Hough said. “It’s not unprecedented to have an intra-plate oceanic earthquake in an oddball location.” Although some offshore earthquakes can become a concern, depending on their proximity to communities or their ability to form a tsunami, Hough said this one was too far and didn’t move the seafloor in such a way. “Being a significant underwater earthquake is not sufficient to generate a tsunami,” according to a tweet from the USGS Earthquakes account Wednesday morning. “The quake also has to move the seafloor vertically, which is not what this quake did.” Hough said a handful of people in California reported to USGS feeling “weak shaking” around the time of the earthquake, but she said it’s hard to confirm if that was a direct result of the oceanic quake. She said she expects this earthquake could trigger more research about intraplate seismic activity and any lingering effects, but otherwise she called it “not that big a deal.” “The expectation is that it’s just an oddball, kind of black swan event that’s in the middle of the Pacific,” Hough said. “But people will be keeping an eye on it.” She said in 2018 oceanic seismic activity off the east coast of eastern Africa led to scientists finding an underwater volcano, but Hough said that was after detecting repeated earthquakes and movement, which she has seen no sign of in this case. But she said it does underscore how some earthquake activity remains difficult to predict or explain, noting that a 6.0 earthquake near Chicago or on the East Coast could cause real damage. “These oddball, intraplate earthquakes can pop up where we haven’t seen them in human lifetimes,” Hough said. “An unlikely place isn’t a problem if it’s in the middle of the north Pacific or well offshore — an unlikely quake close to people is a problem.” I think Lowell addressed the issue of the odd seismo and moment tensor showing the large expansion movement better with his theory...although his theory has issues (like, where's the tsunami waves?). But, again, it seems like they are all puzzled by this one. |
96263
From: jordan, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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here is a good twitter by Jason Jay on the event. looks like there is fault at the epicenter. |
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96243
From: pamela, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Thanks for posting this Seems she doesn't know about the 7.5 off Lompoc,Ca in 1927. Although maybe she doesn't consider Lompoc off S Calif coast? I posted wikipedia link about it. she wrote: Since 1900, there have been only 10 other recorded earthquakes in the north Pacific Ocean off Southern California’s coast — and of the temblors more than 500 miles from the coast, all measured under 5.0 magnitude, according to the USGS. Definitely one to research more about. |
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96235
From: pamela, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Thanks Red, I also asked John Vidale, PNW discussion group on FB what his thought might be for the event, so far no word back. |
96237
From: Redhart, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Vidale would be a good one to ask, but may be disinclined to return to this site lol. I think he used to be here, but got fed up and left when his expertise got questioned.But, he certainly has the bonifides. |
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96240
From: pamela, [DNS_Address]
Subject: Re: Lowel Whiteside summary of 6.0 N Pacific quake
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Yes, I know, thats why I asked him about it on his site on FB. Will share if I hear back. |
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