2024 New Year's Day - 7.6 earthquake in Japan
- Thread starter seek10
- Start date
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- earthquake japan tsunami
ImaPrototype
Jedi
Great time to review earthquake predictions from the scary Session 21 January 1995.
- Sequence of earthquakes to hit Japan (Osaka M8.9, Tokyo M9.6,...).
- Surrounding areas (China, Korea, Philippines, etc) will be affected by these quakes.
- Some volcanos are waking up.
- Quakes in Asia may trigger quakes in California (San Gabriel Mountains M8.9).
- Destruction will lead to mass exodus from California. Economic impact, people moving east.
- Hundreds of earthquakes all over the place.
- Not just earthquakes... storms and hurricanes too!
- Natural phenomena. Mother Nature gets out of bed.
I asked myself if these videos were from today or from 2011.
X should create a video comparison software and put when the video's are FIRST published. It was impossible to figure out which is the current one and which one is older one. Most of the video are reshared so many times it is hard to know the initial date. I checked who is the real poster for one and found to be some one in Japan. But it looks many others are not from Japan. Even that may not be sufficient.
Breo
Dagobah Resident
The Tsunami warning was "downgraded" just today.
Up to now, a Time report writes, there was one area with one wave, 3m high. In other areas 0,5-1,2m. This is a screenshot of this CNN news video:
Up to now, a Time report writes, there was one area with one wave, 3m high. In other areas 0,5-1,2m. This is a screenshot of this CNN news video:
All the tsunami videos in the first post show the tsunami of March 2011.
Still, what a rocky start to 2024!
This report says four people were killed as a direct result of the quake, thousands are in shelters, and tens of thousands more are still without power.
What stands out for me is the date, obviously, but also where it struck: a part of Japan which scientific authorities there estimated had a "0.1% - 3%" chance of experiencing a >6.0 quake "in the next 30 years."
Another FAIL for "the experts."
In fact, it looks like the 'inner side' of Japan, its western coast, has very rarely had a strong quake (in the modern era anyway).
I can't find specific media reports about this, so FWIW: purported footage of fires spreading in the city of Wajima, which is located on the Noto peninsula, the part of Japan that protrudes into the Sea of Japan, and which was hardest-hit by the quake:
I had once commented on one of Jason "Jay" R. Patton's tweets about the nature of the sun's ability to cause seismic activity on Earth.
But he just brushed it off as nonsense.
Nevertheless, he does show some interesting facts with charts of the plate interactions between continents and other data that seem relevant to the conversation. PS to modes: He may have a copyright on his material if that makes a difference.
So, I'll show a snip of a very long thread.
Last night (my time) as I was winding down, I heard my phone go ‘tinggggg.’
A few moments later I got up and learned of a M 7.5 earthquake offshore of the west coast of Japan.
This place has had some recent seismicity (largest magnitude M 6.5; Kato, 2023), though I did not write up a report.
This earthquake was a shallow crustal fault earthquake associated with the Noroshi-oki fault.
This fault is a crustal reverse fault (compressional) that dips to the southeast. Kato (2023) plotted seismicity from a previous sequence and I include the plots from their paper below. These plots reveal the orientation of this fault system.
The aftershock pattern (see poster below) suggests that the entire fault slipped during (or shortly before or after) this M 7.5 mainshock.
There was a tsunami generated by this earthquake. Below are plots from the gages that have a clear record of the tsunami.
The nearest gage (Noto) is located very close to the epicenter and the data suggest that the gage has been damaged in some way.
Empirical fault scaling relations are ways that we can compare fault rupture sizes with earthquake magnitudes. One of the most used and well-cited empirical fault scaling relations papers is Wells and Coppersmith, 1994.
Continued
But he just brushed it off as nonsense.
Nevertheless, he does show some interesting facts with charts of the plate interactions between continents and other data that seem relevant to the conversation. PS to modes: He may have a copyright on his material if that makes a difference.
So, I'll show a snip of a very long thread.
Last night (my time) as I was winding down, I heard my phone go ‘tinggggg.’
A few moments later I got up and learned of a M 7.5 earthquake offshore of the west coast of Japan.
This place has had some recent seismicity (largest magnitude M 6.5; Kato, 2023), though I did not write up a report.
This earthquake was a shallow crustal fault earthquake associated with the Noroshi-oki fault.
This fault is a crustal reverse fault (compressional) that dips to the southeast. Kato (2023) plotted seismicity from a previous sequence and I include the plots from their paper below. These plots reveal the orientation of this fault system.
The aftershock pattern (see poster below) suggests that the entire fault slipped during (or shortly before or after) this M 7.5 mainshock.
There was a tsunami generated by this earthquake. Below are plots from the gages that have a clear record of the tsunami.
The nearest gage (Noto) is located very close to the epicenter and the data suggest that the gage has been damaged in some way.
Empirical fault scaling relations are ways that we can compare fault rupture sizes with earthquake magnitudes. One of the most used and well-cited empirical fault scaling relations papers is Wells and Coppersmith, 1994.
- Wells and Coppersmith developed relations between earthquake magnitude/moment magnitude and surface rupture length, subsurface rupture length, and rupture area. They also consider the difference between mean and maximum displacement measures.
- The length of fault rupture is the distance that the fault slipped measured parallel to Earth’s surface. When we see fault lines mapped on a map, these lines are representative of the fault length.
- The width of fault rupture is the distance that the fault slipped measured down into the Earth. For a fault that dips straight down into the Earth (perpendicular to the Earth’s surface), the width of the fault rupture is the distance between the Earth’s surface and the depth where the fault slipped. For faults that dip at an angle (like along a subduction zone, or a reverse/thrust fault like the fault that caused this M 7.5 earthquake), the distance measured is measured along this non-perpendicular distance.
- The area of fault slip is basically the fault length times the fault width.
- Here is the USGS fault slip model for the M 7.5 earthquake. The length of the fault slip figure is about 40 kilometers (km) and the width of the fault is about 45 km. The color represents the amount that the fault slipped (in meters) during the earthquake. So, the slip area does not fill this entire area. Most of the slip length is within ~180 km and width is within ~180km. The maximum slip is ~3.7 meters.
If we look at the spatial extent of aftershocks (which may indicate the slip region of the earthquake), the length is about 150 km. This is slightly shorter than the USGS fault slip model.
- There have been some updates to these scaling relations that attempt to improve these relations. However, Wells and Coppersmith still work pretty well (the updates are not really that much different).
- There remain certain types of earthquakes where we have small amounts of information to constrain these relations for those types of earthquakes (particularly large magnitude earthquakes, which are more rare than small and medium sized earthquakes). So, there is room for improvement.
Continued