Posted on 12/28/2018 6:40:37 PM PST by Libloather
An aftershock that shook Southcentral Alaska around 5:21 a.m. Thursday is the latest in a series of more than 6,100 since the Nov. 30 earthquake, according to the Alaska Earthquake Center. It’s also the strongest one in weeks, with a reviewed magnitude of 4.9.
With aftershocks expected to continue for several more months, the Anchorage Daily News asked Natalia Ruppert, a seismologist with the Alaska Earthquake Center in Fairbanks, to shed some light on what’s really happening underneath the earth and what it means for Alaska residents.
Why does an earthquake’s reported magnitude sometimes change?
Thursday’s aftershock was originally reported as a 5.0, but its magnitude was changed to 4.9 within a few minutes. That’s because of how the Alaska Earthquake Center measures seismic waves, Ruppert said.
The center has about 500 sensors placed throughout the state. When an earthquake happens, the sensors nearest to the epicenter will be the first to record its location and magnitude, with more and more sensors recording data as the seismic waves travel outward. Ruppert said that because the sensors record data in real time, the preliminary magnitude that the algorithm records in the first few moments after the earthquake may not be entirely accurate.
(Excerpt) Read more at adn.com ...
The question is not “why do they change?” ...the question is why is that change always DOWN?
When plate tectonics stop.
“The question is not “why do they change?” ...the question is why is that change always DOWN?”
This guy, Dutchsinse, has a lot of experience with this:
https://m.youtube.com/user/dutchsinse
when do these stop being aftershocks?
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Next Thursday? ;-)
Dutchsinse also brings up where USGS sometimes doesn’t even report when earthquakes occur, and usually it’s because he may have predicted a quake(s) in the area of omission.
USGS is probably as corrupt as other federal agencies.
DUTCHSINSE Earthquake3D Live Stream - 24/7 Global Seismic Activity
Large 7.0 earthquake just hit Pondaguitan, Philippines area. The Ring of Fire is active.
Thanks for the catch.
A tsunami warning site has no warnings for that quake but it has it as a 7.2. It probably has been downgraded to the 7.0 but occasionally they do get upgraded. I’ll have to check back in awhile
CLEVELAND(ALEUTIAN ISLANDS): SHORT DURATION ERUPTIVE EVENT AROUND 29/0317Z (Anchorage VAAC)
small event.
Cleveland volcano Stratovolcano 1730 m (5,676 ft) Aleutian Islands, Alaska, 52.83°N / -169.94°W Current status: minor activity or eruption warning (3 out of 5)
And Dutchsince keeps on doing his thing!
He’s a smart little toot!
:-)
Thanks, stars & stripes!
Now - off to get some shut-eye.
Nite!
Yep...I always watch Dutchsinse after a quake. He reports the actual magnitude.
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