Magnitude 9.0 Earthquake - OFF THE WEST COAST OF NORTHERN SUMATRA

USGS Earthquake Hazards ^ | 2004 December 26 00:58:55 UTC

[bd476]

Magnitude 8.1 - OFF THE WEST COAST OF NORTHERN SUMATRA
2004 December 26 00:58:55 UTC

Preliminary Earthquake Report
West Coast and Alaska Tsunami Warning Center/NOAA/NWS

A great earthquake occurred at 00:58:55 (UTC) on Sunday, December 26, 2004. The magnitude 8.1 event has been located OFF THE WEST COAST OF NORTHERN SUMATRA. (This event has been reviewed by a seismologist.)

Magnitude	8.1
Date-Time	Sunday, December 26, 2004 at 00:58:55 (UTC) = Coordinated Universal Time Sunday, December 26, 2004 at 6:58:55 AM = local time at epicenter
Location	3.400°N, 95.700°E
Depth	40 km (24.9 miles) set by location program
Region	OFF THE WEST COAST OF NORTHERN SUMATRA
Distances	235 km (145 miles) S of Banda Aceh, Sumatra, Indonesia 330 km (205 miles) W of Medan, Sumatra, Indonesia 1620 km (1000 miles) NW of JAKARTA, Java, Indonesia 3405 km (2120 miles) SE of NEW DELHI, Delhi, India
Location Uncertainty	Error estimate not available
Parameters	Nst=020, Nph=020, Dmin=>999 km, Rmss=0.98 sec, Gp=101°, M-type=moment magnitude (Mw), Version=1
Source	West Coast and Alaska Tsunami Warning Center/NOAA/NWS
Event ID	at00000264

Location Maps: 10-degree NEIC Maps Did you feel it? Report shaking and damage at your location. You can also view a map displaying accumulated data from your report and others. Historical Moment Tensor Solutions Seismic Hazard Map Historical Seismicity Theoretical P-Wave Travel Times Magnitude 7 and Greater Earthquakes This Year TsunamiBulletin Archive of newsworthy events

[bd476]

Thanks Capitan. That's a very large area with very large earthquake potential. Kinda reminds me of the San Andreas fault, only bigger.

[bd476]

LOL, mind reader.

[capitan_refugio]

"Kinda reminds me of the San Andreas fault, only bigger."

About twice as big.

[capitan_refugio]

I suspect we won't know the actual measurements of seafloor displacement for a while. The area will have to be surveyed and compared to earlier survey records.

There are reports of 100-foot (lateral?) displacement on the island of Sumatra - but I discount those as fantastic until I see the evidence. It is easy enough for a geodetic marker to get caught up in a landslide.

[oceanperch]

I totally understand now, I have an excercise/lap pool that I often displace water out onto the floor by the waves I make.

The waves end up bowling around the curved edges and lap over onto the floor in the shallow/step area.

[Quix]

Interesting.

In the last big quake I was in, in Taiwan--I think the big one that caused the deaths . . .

Taiwan got 3 meters narrower and 1 meter taller.

It seems to me that we have satellites that could tell us virtually instantly what the differences were. Perhaps it would take some fancy calculations and perhaps it's a straightforward measurement. I don't know that much about our capabilities.

[capitan_refugio]

Usually science fiction movies are more like science fantasy. A few years ago there were a couple of movies about asteroid/comet impacts with the earth. One had Bruce Willis, IIRC.

One thing these movies had right was that a asteroid impact in the ocean could cause a gigantic tsunami, unlike anything caused by an earthquake or volcano. There was a sci-fi book written a couple of decades ago called "Lucifer's Hammer" (I can't remember the author off the top of my head). There was a scene in the book about surfers in Santa Monica Bay attempting to ride a tsunami. It's sort of funny when you think about it.

[oceanperch]

I also noticed the last couple of months if you hit on a story near the top of the page of on the earthquake page you hit the first choice you automtically get redirected to the ad above on each particular page then you have to back browse and rehit the info you want.

Annoying but also dishonest on clicking on ads.

[capitan_refugio]

My kids slept through the Northridge quake also, but I was about 50 miles from the epicenter (near Ventura). I was awake, however, because our infant youngest daughter had awakened at 4:00 a.m. to be fed. So I was wide awake and sitting on the edge of the bed, as my wife put the baby back to sleep. Being the geologist that I was, I started counting the seconds between the first P-wave arrival and the first S-wave arrival to calculate how far I was from the epicenter. As the surface waves rolled in, I thought better of my dedication to science and took a position next to my wife, on floor, covered in blankets and pillows. I rode out the remainder of the earthquake with only my butt exposed to danger.

[Quix]

Perhaps paranoia . . .

but contemplating moving back to Taipei . . . eagerly . . . and the prediction that there will be an 8.X in Taipei . . .

Have been wondering what kind of 4 X 4 structure I could arrange around and over my bed for safety! LOL. Concrete multi-story apt building steel frame is the rule.

[bd476]

Didn't know you were local to S. California or that you are a geologist, Capitan. Did you see Kate Hutton just now on KTLA?

She was explaining that the earthquake occurred on a thrust fault zone. She also mentioned that in comparison, this quake lasted perhaps 3-4 minutes whereas the 1994 Northridge quake lasted 10-15 seconds.

The Northridge quake seemed more like 2 minutes to me. Of course I was hanging on to my bed for dear life so that I wouldn't be shaken off of it.

"Telling signs" I saw a day or two before the 1994 quake were two large runaway and deceased dogs on the Ventura Freeway where I had never seen runaway dead animals before.

My cat was trying to dig a hole to China in the litter box about one hour prior to another large quake. Quite startling. She'd empty the entire box of the clean litter, I'd dash out, sweep it up and place it back in the litter box, and then she'd start all over scratching and pushing it out again and again.

Then I heard a very deep moaning sound, and I thought she was getting ready to throw up a large fur ball or that perhaps she had found a mouse or something. Then kapow, crash bang and she hissed and screamed and I thought someone had broken in. Then came relief upon the realization that it was "just a quake."

[jbstrick]

"And then he has the [knots] to brag about how many 'hits' his site gets! Sheer balls, he's got!"

Actually, reloads don't count, only individual daily page views from different IP addresses.

[bd476]

LOL, gotta hand it to you for your candor. Either that or you are a terrific swimmer! :) But it's a great example.

[bd476]

Ping.

[bd476]

Here's information I found regarding the timing of the tsunamis and how long they occurred after the earthquake:
Post 739

[capitan_refugio]

Sorry I missed it. I don't watch too much TV, other than a couple of shows on FNC.

The farther away you are from the epicenter of the earthquake, the longer it lasts (but the lesser the intensity of shaking) - as a rule of thumb. This is beacuse the wave-train "spreads outs" away from the hypocenter.

the 1857 Fort Tejon quake (the model of the "big one" for southern California) reportedly shook for about three minutes. Professor Kerry Sieh at Cal Tech collected first-person accounts of that earthquake while doing some of his great work on the San Andreas Fault. Ealy in my career, I was lucky enought to be be on a couple of his seminar/field trips.

It is well-recognized that animals are sensitive to slight earthquake temors. In fact, P-waves are the same as sound waves and are just barely in the audible range of humans. Animals may sense, or hear, some P-wave arrivals we don't recognize.

[Gal.5:1]

9.0

13,000 dead

:O..

[FReepaholic]

The whole world is shaking. I got these seismographs from the USGS.gov live internet seismic server.

Any seismologists out there?

There's a bunch more at the link below:

http://aslwww.cr.usgs.gov/Seismic_Data/heli2.shtml

Albuquerque, New Mexico

Beijing, China

Ankara, Turkey

[capitan_refugio]

I don't know where you are now located, but the Circum-pacific Seismic Belt accounts for about 70-80% of the earth's seismic activity (earthquakes and volcanoes).

Taiwan is part of that seismic zone, just like southern California - where I am located. Of course, there is no place totally immune to some sort of natural disaster. Just pick your poison!

[bd476]

"This map shows the predicted (theoretical) travel times, in minutes, of the compressional (P) wave from the earthquake location to points around the globe.

The travel times are computed using the spherically-symmetric IASP91 reference earth velocity model. The heavy black lines shown are the approximate distances to the P-wave shadow zone (103 to 140 degrees)."

Theoretical P-Wave Travel Times

City	Distance (degrees)	Travel Time (min:secs)	Arrival Time UTC	Phase
Kathmandu, Nepal	26.24	5:35.1	1:04:25.1	P
Beijing, China	40.97	7:42.8	1:06:32.8	P
Agana, Guam	49.40	8:49.7	1:07:39.7	P
Tokyo, Japan	51.81	9:07.9	1:07:57.9	P
Nairobi, Kenya	59.10	10:00.4	1:08:50.4	P
Brisbane, Australia	63.01	10:27.0	1:09:17.0	P
Moscow, Russia	69.78	11:10.4	1:10:00.4	P
Rome, Italy	82.80	12:24.4	1:11:14.4	P
Wellington, New Zealand	83.92	12:30.1	1:11:20.1	P
Bergen, Norway	87.38	12:47.3	1:11:37.3	P
London, England	91.15	13:05.0	1:11:55.0	P
Anchorage, Alaska	98.57	13:38.7	1:12:28.7	Pdiff
Honolulu, Hawaii	104.00	14:02.9	1:12:52.9	Pdiff
Palmer Station, Antarctica	114.17	14:48.0	1:13:38.0	Pdiff
Seattle, Washington	119.18	15:10.2	1:14:00.2	Pdiff
San Francisco, California	125.94	15:40.2	1:14:30.2	Pdiff
Duluth, Minnesota	129.68	15:56.8	1:14:46.8	Pdiff
Bangor, Maine	130.17	15:59.0	1:14:49.0	Pdiff
Ottawa, Canada	130.91	16:02.3	1:14:52.3	Pdiff
Los Angeles, California	130.93	16:02.4	1:14:52.4	Pdiff
Golden, Colorado	133.02	16:11.7	1:15:01.7	Pdiff
Boston, Massachusetts	133.05	16:11.8	1:15:01.8	Pdiff
New York, New York	135.22	16:21.4	1:15:11.4	Pdiff
Philadephia, Pennsylvania	136.17	16:25.6	1:15:15.6	Pdiff
Albuquerque, New Mexico	136.41	16:26.7	1:15:16.7	Pdiff
Wichita, Kansas	137.37	16:31.0	1:15:21.0	Pdiff
Washington, D.C.	137.50	16:31.5	1:15:21.5	Pdiff
St. Louis, Missouri	137.88	16:33.2	1:15:23.2	Pdiff
Knoxville, Tennessee	140.95	16:46.9	1:15:36.9	Pdiff
Brownsville, Texas	148.25	19:42.3	1:18:32.3	PKPdf
Miami, Florida	150.85	19:46.4	1:18:36.4	PKPdf
San Juan, Puerto Rico	151.97	19:48.1	1:18:38.1	PKPdf
Mexico City, Mexico	153.07	19:49.7	1:18:39.7	PKPdf
Lima, Peru	168.74	20:06.6	1:18:56.6	PKPdf