April Fools’ Day tsunami reduxed (1946 tsunami killed 159 people in Hawai’i)

 

 

*

*

*

http://www.kitv.com/news/80magnitude-chile-quake-being-evaluated-for-hawaii-threat/25275288

(the 1946 & 1960 earthquakes were measured by the lower Richter scale  — thence the strongest ever earthquake on record, the same 1960 Chile earthquake which killed 61 people in Hawai’i, had a Richter reading of 8.6 but a current moment magnitude of 9.5  — the news report linked above erroneously lists the 1946 earthquake at 8.6 Richter magnitude — it was actually 7.8)

  http://en.wikipedia.org/wiki/List_of_earthquakes#Largest_earthquakes_by_magnitude

http://www.tsunami.org/archivespics.html

https://en.wikipedia.org/wiki/Megathrust_earthquake

*

http://www.livescience.com/3732-mystery-deadly-1946-tsunami-deepens.html

https://en.wikipedia.org/wiki/Slow_earthquake

*

from tsunami expert Gerard Fryer April 5, 2017   —

Aloha Curtis.

The earthquake which spawned the 1946 tsunami displayed exceptionally slow rupture, as Lopez & Okal showed (they calculated that the rupture speed was about one kilometer/second, only about a third of the speed shown by most earthquakes). The slow rupture was accompanied by a huge slip—the distance one side of the fault moved relative to the other. What the actual slip was we don’t know for sure, but if you try to model the tsunami that hit Hawaii, you need a slip of at least 30 meters. Why the slow slip? Again, we don’t know for sure, but rupture reaching up into shallow, weak, sediments is the likeliest cause. [emphasis is Curtis’]

Could one of these tsunamis [tsunami earthquake event] sneak in and hit us unawares? Until about 1990, the answer was probably “Yes.” Now, though, I’m confident that we would get the measure of the earthquake in time.

For all earthquakes above about magnitude 6.5, PTWC runs a slowness check which looks at how the energy radiated at short periods compares to that at long periods. Slow earthquakes push out a lot more energy at long periods. This check is only possible because of the worldwide distribution of broadband seismometers: there are at least 700 such instruments all over the Earth and almost everybody shares their data in real time.

All the best,

-Gerard

On Apr 5, 2017, Curtis Narimatsu  wrote:


Hi Gerard:   I ponder Okal’s study which overlays tsunami earthquake” discussions.
 Tsunami earthquake

*

Did the 1946 Aleutian earthquake have a slip which amplified (via soft clay) the tsunami?

Will a “tsunami earthquake” be our “silent/quiet killer” undetected by current technology?

 

Thanks, Gerard   — always, Curtis

*

*

*

http://safercoastlines.com/2014/10/hawaii-huge-risk-of-mega-tsunami-discovered/

*

Via a 2,000 year time period, the Aleutian Islands spot (equidistant between the location sources of the 1946 tsunami to the east and the 1957 tsunami to the west) will send a 9.4 moment magnitude generated tsunami straight ahead to the Hawaiian Islands with 105 ft. high runups (from sea level to the highest point on land) which will cause utter devastation to all low-lying areas.   Such a tsunami is overdue inasmuch the center spot has not had such a humongous event over the past 2,000 years.   Mayor Harry Kim foolishly discards the risk of the overdue event.   After what science discovered via the 2011 Japan tsunami, it is criminal to overlook such an apocalyptic event.    The evacuation areas in Hilo include clearing everyone oceanside of our Prince Kuhio Plaza, as a conservative measure.

*

http://www.staradvertiser.com/breaking-news/geologists-say-section-of-aleutian-islands-could-send-devastating-tsunami-to-hawaii/

*

https://www.youtube.com/watch?v=09xQ8n6GiTY

*

the 2011 Japan tsunami at Soma port was twice as high as the deadly waves which hit Hawai’i in 1946 & 1960, not to mention that the seashore sank 3 feet along Japan’s northeast coast (thereby rendering useless  all anti-tsunami seawalls except for Fudai’s 50 ft. high barrier  — https://www.youtube.com/watch?v=XhxlBGzNyzk  )    —     while all of Honshu moved 8 feet eastward.   

http://en.wikipedia.org/wiki/2011_T%c5%8dhoku_earthquake_and_tsunami 

*

http://www.youtube.com/watch?v=M2v6VMqRA5w

*

*

http://www.youtube.com/watch?v=ibewcn1-mEI&index=34&list=PL42F01C0B2AEAC1C9

*

all 5  employees at the Soma port office miraculously survived   — go to timeclock 13:13 here

 

https://www.youtube.com/watch?v=gLQZ4P6CASk

*
*
*
*

Japan’s “giant” mega-thrust earthquake generated tsunamis    —   the interval is one such tsunami every one thousand years  —

*

(6 mega-thrust tsunami events 1,000 years apart between 6,000 B.C. & 100 A.D., then the 869 A.D. Jogan Sanriku tsunami, then the 2011 A.D. Tohoku tsunami   —

 

*

http://factsanddetails.com/japan/cat26/sub160/item1741.html

*

http://factsanddetails.com/japan/cat26/sub161/item1742.html

*

2011 megathrust tsunami predicter Yasutaka Ikeda   was ignored     —

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

Yasutaka Ikeda

*

http://www.earthmagazine.org/article/superquakes-supercycles-and-global-earthquake-clustering-recent-research-and-recent-quakes

http://news.nationalgeographic.com/news/2011/03/110315-japan-earthquake-tsunami-big-one-science/

https://www.washingtonpost.com/national/in-ishinomaki-japan-stories-of-survival-and-loss/2011/03/28/AF6FPoyB_story.html

http://openoregonstate.pressbooks.pub/earthquakes/chapter/16-an-uncertain-appointment-with-a-restless-earth/

*

also,   http://theweek.com/articles/485635/geologist-who-predicted-japans-tsunami

*
*
*
*
*

supercritical wave flow focus (even reinforced concrete is destroyed by large lateral force of water)    go to timeclock 29:30  (Kuji port)  —

https://www.youtube.com/watch?v=j2FHoOUyZ-k

 *
*

lateral force hazard generally   — timeclock :46 (Onagawa city)   —

https://www.youtube.com/watch?v=i-5cJseEsmc

*

http://www.jsnds.org/jnds/23_2_3.pdf

*

https://en.wikipedia.org/wiki/869_Sanriku_earthquake

*

*
*

http://www.abc.net.au/catalyst/stories/4099073.htm

*

*

*

http://extremeplanet.me/2014/02/04/detailed-imagery-of-the-2011-japan-tsunami/

*

*

http://www.sciencedaily.com/releases/2011/12/111205181924.htm   (underwater topography/bathymetry can amplify wave pulse energy)

*

*

*

*

“Slow” quakes  might correlate with  eventual  enormous waves  —

 

http://www.smithsonianmag.com/science-nature/slow-earthquakes-are-thing-180960248/

 

https://en.wikipedia.org/wiki/Slow_earthquake

*

http://www.nature.com/news/in-japan-small-shakes-presage-big-quakes-1.19252

*

http://www.voanews.com/content/subtle-seismic-activity-hints-predicting-large-quakes/3167842.html

*

http://theconversation.com/rumbling-from-ocean-trenches-could-be-sign-that-japan-faces-mega-earthquake-41464

*

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4260540/

*

http://www.oneindia.com/international/slow-motion-earthquakes-may-also-lead-tsunamis-2091387.html

*

http://phys.org/news/2016-05-world-shallowest-slow-motion-earthquakes-offshore.html

*

https://www.sciencedaily.com/releases/2016/05/160505144723.htm

*

*

*

timeclock 14:58 to 18:44 (asperity means rough stuck area)    —

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

*

*

*

timeclock 16:19 to  17:25  —

*

*

*

timeclock 23:22       https://www.youtube.com/watch?v=MUmcrezGEAk

http://onlinelibrary.wiley.com/doi/10.1002/2015GL063959/full

https://www.fujipress.jp/jdr/dr/dsstr000900030317/

*

 

*

*

*

*

http://www.ft.com/cms/s/0/9e502e56-5970-11e4-9546-00144feab7de.html

http://www.cam.ac.uk/research/news/scientists-explain-scale-of-japanese-tsunami   (issue of underwater “landslides”)

*

http://www.thestar.com/news/world/2012/05/30/japan_earthquake_and_tsunami_disturbed_upper_atmosphere_nasa.html  (do animals sense oncoming earthquake/tsunami?)

*

*

*

*

go to timeclock 12:05 to see “tennis court vertical netting”   — then continue 2 seconds later to  timeclock  12:07  to view the virtual bone-chilling “lake”  —

*

http://www.youtube.com/watch?v=ARv_4a_8FBA

*

*

*

*

*

*

*

*

*

*

http://www.foxnews.com/us/2014/04/02/tsunami-advisory-for-hawaii-cancelled-after-large-earthquake-off-coast-northern/

*

*

*

*

*

*

Miyako city in Iwate Japan   —

*

*

*

includes post-tsunami photo at bottom  —

*

http://www.bing.com/images/search?q=miyako+iwate+tsunami+map&qpvt=miyako+iwate+tsunami+map&FORM=IGRE#view=detail&id=9CF3E71683AD15F2C29535EFDF20C5D3C093BAD6&selectedIndex=35

*

*

*

*

*

*

*

*

epicenter 30 miles east of Ishinomaki in Miyagi prefecture —

*

http://en.wikipedia.org/wiki/Japan_tsunami#mediaviewer/File:Tsunami_map_Tohoku2011.svg

*

*

*

*

*

*

Koshirahama port in Toni, Kamaishi, Japan

*

 (http://www.youtube.com/watch?v=HwX2s4HnHNU)

*

go to video below to timeclock 2:33 to see van & flatbed truck by “tunnel” carport  —  50 ft. above usual sea level at 5:40 (but seashore sank by 3 feet, thus amplifying the inundation)  —

*

eventually be met by inundation (go to 5:58 to see 37.5 ft. high seawall blocks toppled back by tsunami “pulse”)

*

http://www.youtube.com/watch?v=t0S9wA3b0Ro

*

*

*

*

same Koshirahama port post-tsunami failure of seawall blocks — hollow insides (to allow vehicles to pass thru)

*

http://www.youtube.com/watch?v=Mc8LuiscCg4

*

*

*

*

*

*

*

*

http://glgarcs.net/intro/subduction.html

*

http://en.wikipedia.org/wiki/Reverse_fault#Dip-slip_faults

Cross-sectional illustration of normal and reverse dip-slip faults

A reverse fault is the opposite of a normal fault—the hanging wall moves up relative to the footwall. Reverse faults indicate compressive shortening of the crust. The dip of a reverse fault is relatively steep, greater than 45°.

A thrust fault has the same sense of motion as a reverse fault, but with the dip of the fault plane at less than 45°. Thrust faults typically form ramps, flats and fault-bend (hanging wall and foot wall) folds. Thrust faults form nappes and klippen in the large thrust belts. Subduction zones are a special class of thrusts that form the largest faults on Earth and give rise to the largest earthquakes.

Thrust with fault bend fold.svg

Types of fault motion

As for the M 9.0 eastern Japan earthquake in 2011, Japan Meteorological Agency reported that the type of earthquake source fault was the reverse fault (thence the initial deluge, not the initial receding trough  — in Hawai’i, one sees more often than not the initial receding trough, though the absence of the receding trough should not lull us into complacency ), the size of fault was about 450 km long and 200 km wide, the fault slippage was 50 meters, and the duration of main failure was about three minutes (The 2011 off the Pacific Coast Tohoku Earthquake [28th report]).

*

*

*

*

*

http://www.livescience.com/41726-japan-earthquake-culprit-slippery-clay.html

*

fault

The Tohoku quake was a magnitude 9.0, but it was like no subduction quake ever seen before. Before the 2011 earthquake, scientists thought subduction zones concentrated their energy deeply, where rocks are strong and plates can stick together between quakes. (Faults store energy between earthquakes kind of like springs, slowly squeezing until the boundary unleashes and everything rips apart.)

*

But the Tohoku temblor was a surprise — the shallow part of the fault shifted twice as much as the deeper part.

*

These soft, muddy rocks were expected to be too weak to store energy between earthquakes.

*

The clay, which resists slipping no better than a banana peel, lines the shallow part of the massive plate boundary fault offshore of Japan, where the

*

seafloor jumped eastward by a staggering 165 feet (50 meters) on March 11, 2011.

*

The enormous surge gave the ocean a giant slap, generating the destructive tsunami that killed more than 15,000 people.

*

*

go to timeclock 1:00 to visualize largest ever recorded 50 meter jump   —

https://www.youtube.com/watch?v=VJIdMvL9KcA

*

*

http://www.youtube.com/watch?v=DkuFbVZEWRA

*

*

http://www.youtube.com/watch?v=8GbjaTxwscM

*

*

*

http://www.upi.com/Science_News/2013/12/05/Slippery-layer-of-clay-increased-force-of-tsunami-in-2011-Japan-quake/UPI-13471386288421/

*

Because of the lubricating effect of the clay sediment, the earthquake created a “slip” of about 150 feet, “which in earthquake terms is among the largest ever measured, and it was unexpected by many earthquake scientists that the fault ruptured all the way up to the seafloor.

*

*

http://news.nationalgeographic.com/news/the-2011-japan-tsunami-was-caused-by-largest-fault-slip-ever-recorded/

*

*

*

*

*

How the great Tohoku-Sendai earthquake and tsunami happened

Slippery Clay Explains Mystery of Tohoku-Oki Earthquake and Tsunami

*

The destructive nature of the Tohoku eathquake stemmed from its occurrence at a shallow depth (~20-30 km) that allowed the motion to shove crustal material eastwards, up and over the sea floor to cause the sea floor to bulge upwards by tens of metres in a matter of seconds. It was that surface-breaking megathrust that displaced Pacific Ocean water and launched the huge tsunami waves. Geophysicists were caught by surprise as regards the magnitude of the event, having long considered that part of the Pacific ‘ring of fire’ to be incapable of generating seismic energies above a magnitude of 8.0; 32 times less energetic than the magnitude 9.0 that was reached in reality. The area to watch was believed to be the southwestern coastline of Japan, affected by subduction beneath the Sagami and Suguma Troughs. The reason for this attempt at anticipation in what is one of the world’s most risky places for seismicity is that now discarded theory suggested that subduction slip was greatest at depth and becomes smaller at shallower levels.

Clearly, a major scientific effort had to be undertaken to explain such a disastrous misconception. Part of this involved drilling into the seabed above the 11 March 2011 epicentre. The extracted rock cores revealed a major surprise (Chester, F.M. and 14 others. 2013. Structure and composition of the plate-boundary slip for the 2011 Tohoku-Oki earthquake. Science, v. 342, p. 1208-1211): the fault zone was a layer of clayey rock less than 5 m thick with a rupture zone for the Tohoku earthquake estimated at only a few centimetres across. Experiments revealed that hardly any heat had been generated by such a huge earthquake (Fulton, P.M. and 9 others 2013. Low coseismic friction on the Tohoku-Oki Fault determined from temperature measurements. Science, v. 342, p. 1214-1217). Friction had been extremely low, probably because the clay was so impermeable that water pressure in it was able to build up and not diffuse away (Ujie, K. and 9 others 2013. Low coseismic shear stress on the Tohoku-Oki Megathrust determined from laboratory experiments. Science, v. 342, p. 1211-12145). The thrust fault was lubricated, but fortunately one that was localized: unlike the strike-slip fault that drove the Indian Ocean tsunamis of 2005 which was able to propagate for over 1000 km (twice as long as the Tohoku fault).

*

It does seem that the Tohoku Fault has developed, probably over millions of years, in particularly clay-rich sea-floor sediments. Such a phenomenal amount of slippage would be less likely in coarser shallow sediments that would probably generate much more friction (less slippage). Putting the findings into practice will involve greater investment in and speeding up oceanographic studies of submarine trench systems.

*

*

http://www.huffingtonpost.com/2015/02/20/tectonic-plates-move_n_6713638.html?utm_hp_ref=science

*

http://www.livescience.com/39110-japan-2011-earthquake-tsunami-facts.html

*

*

*

The 2011 Japan tsunami truly was of biblical proportion  —

*

http://www.youtube.com/watch?v=B004JAN0Ahg

*

*

*

*

*

*

*

sights/sounds of folks watching tsunami   –

*

*

*

*

Named cities/sites in this 2011 Japan tsunami video  —

*

http://www.youtube.com/watch?v=eeLlySDmjuw&list=PL253E9432D0905298&index=67

*

*

*

*

*

July 11, 2014 earthquake same tectonic plate general location Japan   –

http://www.rappler.com/world/regions/asia-pacific/63103-japan-more-aftershocks-2011-earthquake

*

*

*

*

*

Tarou Japan’s “model” (perfect) tsunami seawalls were no match for the 2011 tsunami.

*

go to timeclock :56 to see seawall “x” configuation

*

then go to timeclock 5:18 of this next video to see the upper right quadrant site of the x configuration in real time     http://www.youtube.com/watch?v=R30VfYgfYek&list=PLLzwDwNidw09lKAwyeLN5FXxYodMKxRfL&index=10

*

*

*

*

*

*

Onagawa cement green-topped bldg. at timeclock  :56  (seconds)   to right of screen is not the one you see in videos below

(Onagawa especially is vulnerable to tsunamis because of its funnel-shaped bay & underwater bathymetry — bay shape & undersea floor layout that funnel & amplify  tsunami pulse)

*

here is different green-topped bldg. at timeclock 1:35:56  (also go to 1:35:22 to see 65 feet inundation measurement)  —

*

different green-topped bldg.  timeclock 1:35     http://www.youtube.com/watch?v=i-5cJseEsmc

*

climbing stairs to Onagawa hospital      http://www.youtube.com/watch?v=84lSkbczBns

*

see also green bldg. & peach-colored bldg. video #156 (Yuichi Tuba) at timeclock   6:07 & at 8:08 here  —  tsunami went up  65 feet along earthen bank of hospital from where this current video is made

*

Here is Onagawa hospital Yamachan video #68  inundated at its ground level 65 feet above sea level, with video cam looking down on it 150 feet above sea level      —

*

*

Onagawa port land sunk  5 feet into the sea       http://www.youtube.com/watch?v=ZhPOZ78V8go&list=PL8rWKwqFW1l02yG1PE0YpyLmdwr6YZfmL&index=62

*

*

*

Onagawa & Kesennuma also were affected by the February 28, 2010 Chile tsunami  — because of both cities’ funnel shaped bays which amplified the tsunami pulse, & because of their underwater bathymetry (seafloor shape) which also amplified the tsunami pulse.

*

*

*

*

*

*

*

*

*

*

Go to timeclock 1:06 of this video to see 2 hilltops in background with town in foreground.   Then go to 8:10 to see a “lake” where the town stood  — tsunami inundation 2011 Japan tsunami.       http://www.youtube.com/watch?v=XXxktSfVvSQ

*

*

*

*

*

at time clock 23 seconds —   these 3 people cannot outrun the tsunami coming across the flat plain over  a mile inland   (Soma area) —

*

*

at time clock 1:24 — the fleeing person gets swallowed in the flood of the onrushing tsunami (at Omoe, Iwate, Japan)  —

*

*

*

*

Rikuzentakata destruction

*

go to timeclock :51 (seconds) to see municipal government bldg. (roof is equivalent to 4th floor)  &  3 story citizen “city” hall at 1:28 that was swallowed up in tsunami    — http://www.youtube.com/watch?v=Wccusd-5rg8

*

see also citizen “city” hall at 12:40 here     http://www.youtube.com/watch?v=j-ElOypQOH8

*

these individuals perched atop the corrugated pitched roof adjacent to the “city” hall presumably perished, inasmuch the bldg. & roof eventually were ripped away by the tsunami  —  go to timeclock 3:43         (go to hothot yochi uploader name on You Tube — look for video with devastated city landscape)       http://www.youtube.com/watch?v=naLHeN1azEk    (removed from You Tube)

 

 

*

go to timeclock 33:38    rooftop perchers gone   https://www.youtube.com/watch?v=Dye9pEsWWyI

*

now see survivors on municipal government building  rooftop  during tsunami  (equivalent to 4th floor)      timeclock 2:21    http://www.youtube.com/watch?v=n5iXBaLM7mI

*

here is 3 story citizen “city” hall after tsunami timeclock 6:07 video no.  11

*

*

Rizkuzentakata incoming tsunami from 5th floor level of building   timeclock 12:16

*

and timeclock 3:05 here       http://www.youtube.com/watch?v=lWrQkR6KUNM

*

same “lanai”  post-tsunami video #151 timeclock 5:03

*

*

*

*

*

Minamisanriku survivors incl. its mayor  — perched atop city gov’t bldg. 45 ft. above street level at timeclock 13:02        https://www.youtube.com/watch?v=tU1dLutdRAM

*

*

*

*

an elementary school tragedy because of school officials’ hubris miscalculation    —

Okawa Elementary School Ishinomaki Japan   (tsunami came from ocean 2 miles away to the right side of the bridge  — school officials had ample time to take the students to the hill to the rear of the school)

*

here is the green-colored iron trestle bridge which is to the left of and higher in elevation than Okawa Elementary School  —

*

here is the same bridge  —

*

leading up to the green bridge from the left side landfall of the bridge —

*

also, here is aerial photo pre-tsunami of area to the left of the bridge  timeclock 58 seconds

 

*

Okawa Elementary School before its destruction   —

*

*

*

*

*

*

*

*

*

*

*

*

*

*

Advertisements
This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s