Quakes – North America

North America String of 5.x

North American Quake Map

North American Quake Map

Clickable map with details.

Not a big deal, no 7.x at all, but I’m not liking that string of 5.x working their way from the Mexico coast toward where I live…

At The Bottom:

Magnitude 5.1 – CHIAPAS, MEXICO

This event has been reviewed by a seismologist.
Magnitude
5.1
Date-Time
Wednesday, September 15, 2010 at 06:05:49 UTC
Wednesday, September 15, 2010 at 01:05:49 AM at epicenter
Time of Earthquake in other Time Zones
Location 15.930°N, 93.072°W
Depth 96.1 km (59.7 miles)
Region CHIAPAS, MEXICO
Distances
70 km (45 miles) ESE of Tonala, Chiapas, Mexico
90 km (55 miles) S of Tuxtla Gutierrez, Chiapas, Mexico
310 km (190 miles) WNW of GUATEMALA, Guatemala
750 km (465 miles) ESE of MEXICO CITY, D.F., Mexico
Location Uncertainty
horizontal +/- 12.4 km (7.7 miles); depth +/- 4 km (2.5 miles)
Parameters
NST= 81, Nph= 96, Dmin=656.8 km, Rmss=1.13 sec, Gp=180°,
M-type=body wave magnitude (Mb), Version=6
Source
USGS NEIC (WDCS-D)
Event ID us2010bfat

Nearer to the Middle:

Magnitude 5.6 – OFFSHORE NAYARIT, MEXICO

This event has been reviewed by a seismologist.
Magnitude 5.6
Date-Time
Tuesday, September 14, 2010 at 23:31:57 UTC
Tuesday, September 14, 2010 at 05:31:57 PM at epicenter
Time of Earthquake in other Time Zones
Location 21.058°N, 106.218°W
Depth 5 km (3.1 miles) set by location program
Region OFFSHORE NAYARIT, MEXICO
Distances
115 km (70 miles) WNW of Puerto Vallarta, Jalisco, Mexico
145 km (90 miles) WSW of Tepic, Nayarit, Mexico
180 km (115 miles) SSW of Acaponeta, Nayarit, Mexico
760 km (470 miles) WNW of MEXICO CITY, D.F., Mexico
Location Uncertainty
horizontal +/- 5.3 km (3.3 miles); depth fixed by location program
Parameters
NST=293, Nph=293, Dmin=481.8 km, Rmss=1.07 sec, Gp= 90°,
M-type=teleseismic moment magnitude (Mw), Version=8
Source USGS NEIC (WDCS-D)
Event ID us2010becx

Near California:

Magnitude 5.1 – GULF OF CALIFORNIA

This event has been reviewed by a seismologist.
Magnitude 5.1
Date-Time
Wednesday, September 15, 2010 at 07:50:08 UTC
Wednesday, September 15, 2010 at 12:50:08 AM at epicenter
Time of Earthquake in other Time Zones
Location 29.887°N, 114.088°W
Depth 10.2 km (6.3 miles)
Region GULF OF CALIFORNIA
Distances
145 km (90 miles) SSE of San Felipe, Baja California, Mexico
165 km (105 miles) SSW of Puerto Penasco, Sonora, Mexico
210 km (130 miles) WSW of Caborca, Sonora, Mexico
1905 km (1180 miles) NW of MEXICO CITY, D.F., Mexico
Location Uncertainty
horizontal +/- 18.8 km (11.7 miles); depth +/- 2.7 km (1.7 miles)
Parameters
NST=250, Nph=258, Dmin=410.8 km, Rmss=1.04 sec, Gp= 79°,
M-type=regional moment magnitude (Mw), Version=6
Source USGS NEIC (WDCS-D)
Event ID us2010bfa3

So you can figure I’m going to be checking my water barrels and making sure nothing heavy is sitting on the shelf over the easy chair ;-)

Honorable Mention

Honorable Mention goes to the 5.0 in Baja on the California boarder and the 5.3 at the end of the Alutian Islands earlier in the week.

Sure makes that Cascadia segment silence stand out…

Live USA Quake Map

Zooming in just a bit on the USA.

Live USA Quake Map

Alaska and California getting some action. Lots of small ones.

California Map

Action Closer to Me

As I live in California, it makes it easier for me if I keep them in the list where I can see what’s shaking near me.

Current quake map in California

Current quake map in California

Original Image, with captions and description. The original is interactive with clickable regions for ‘close ups’.

Looks like a little more fresh action in Baja and the rest of the place is still shaky.

Mammoth Lakes / Long Valley Volcano

Because I want to know if it starts to blow it’s top…

Mammoth Mountain - Long Valley Super Volcano

Both Hemispheres

A view of Earthquakes from the South Pole

A view of Earthquakes from the South Pole

Original Image with Clickable Details

North Polar Earthquake Map

North Polar Earthquake Map

Original Image with Clickable Details

If you click the links to the originals you can not only ‘click through’ to any given area or quake, but by clicking on the little blue diamonds you can rotate the globe to different points of view. It’s kind of fun…

The Whole World View

Current quake map

Current quake map

Original Image, with captions and description. The original is interactive with clickable regions for ‘close ups’.

North America Map

Simply because it’s where one side of the Ring of Fire goes.

Current quake map in North America

Current quake map in North America

Original Image, with captions and description. The original is interactive with clickable regions for ‘close ups’.

Australia, New Zealand and Indonesia

How about a look at that Near Australia edge of the Ring of Fire? “What’s happened lately” where those pesky Indonesian volcanos sporadically cause a little ice age?

Australia Region Quake Map

Australia Region Quake Map

Original Image, with captions and description. The original is interactive with clickable regions for ‘close ups’.

We’ve also got, as I type, red boxes in South America and near Antarctica. Things are happening right now, but mostly in the 5 range.

Here is a South America centric view:

South America Centric Quake Map

South America Centric Quake Map

Original Image with Clickable Details

Active, along with ‘near Australia’.

About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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27 Responses to Quakes – North America

  1. Catherine Clark says:

    Yes, it does make the Cascadia silence stand out. I have been madly doing research on the CSZ and what I have read makes me very uneasy. I am from the PNW and have a lot of family up there and a lot of good friends. I don’t even see tiny quakes happening; the closest quakes are Southern Oregon and the Mendocino Triple Junction, and the ones in Southern Oregon are offshore close to the Farallon Plate; do they count for the CSZ? I don’t know, but the longer the silence from the CSZ the more and more uneasy I grow, particularly when I read about the silent quakes and how they have presaged big quakes in Japan. What worries me most is that a CSZ quake could trigger a Seattle fault quake and the history of those is scary also! Tsunami waves on Puget Sound are scary indeed!

  2. RuhRoh says:

    Speaking of websites with insufficient graphix, this topic seems to be ripe for some animation of recent history. (by them, not you)…

    Maybe the problem is that they are geologists, and not used to dynamic maps…

    Heck, with the right graphical presentation, someone might even notice a pattern. I mean, the breakthrough realization that NA/SA seem to fit next to Europe/Africa is getting a bit long in the tooth…

    But then again, the world didn’t even notice those bee You tee full hair graphs, let alone imitate them…

    Oh Well,
    RR

  3. boballab says:

    @Catharine

    A couple of months ago I pointed out to EM about the silence of the Cascadia compared to what was happening above and below it. Not too long afterwards there had been 2 smallish quakes in the area. However instead of being reassuring that it was just a stress reducer that is an ominous sign since the Cascadia is supposed to be “locked” atm and can’t move.

    Outside of the New Madrid fault, Cascadia is the other not well known, but when it goes it goes big, fault in North America. So it interests me more then the famous San Andreas atm.

    @EM

    He he, I believe I mentioned something about the quakes seem to be moving north after starting down in South America last month.

  4. E.M.Smith says:

    They have a 7 day ‘animation’ here:

    http://earthquake.usgs.gov/earthquakes/recenteqsanim/

    I just haven’t bothered to figure out how to embed it yet…

    @boballab:

    IIRC, the Cascadia had a bracket of two 5.x or so on each END where there is the triple junction.

    And yes, you did mention them moving North. Might I ask that you please mention California suddenly being bypassed as the Quakes jump to Alaska? … ;-)

  5. E.M.Smith says:

    Oh, looks like Anchorage Alaska got a 5.0 too:

    Magnitude 5.0 – SOUTHERN ALASKA

    This event has been reviewed by a seismologist.
    Magnitude 5.0
    Date-Time
    Wednesday, September 15, 2010 at 16:06:41 UTC
    Wednesday, September 15, 2010 at 08:06:41 AM at epicenter
    Time of Earthquake in other Time Zones
    Location 59.863°N, 153.171°W
    Depth 120.8 km (75.1 miles)
    Region SOUTHERN ALASKA
    Distances
    75 km (45 miles) SSW of Redoubt Volcano, Alaska
    95 km (60 miles) WNW of Homer, Alaska
    235 km (145 miles) SW of Anchorage, Alaska
    1080 km (670 miles) WNW of JUNEAU, Alaska
    Location Uncertainty
    horizontal +/- 0.4 km (0.2 miles); depth +/- 0.1 km (0.1 miles)
    Parameters
    NST= 61, Nph= 70, Dmin=21.9 km, Rmss=0.55 sec, Gp= 72°,
    M-type=local magnitude (ML), Version=2
    Source
    Alaska Earthquake Information Center
    Geophysical Institute, University of Alaska Fairbanks
    Event ID ak10078953

    Golly, maybe it’s enough that I just wish for it… 8-}

  6. Catherine Clark says:

    I am familiar with the NMSZ, as I live in Chicago and do EQ research. It hasn’t moved since the early 1800’s, when it moved in a big way. There seem to be two bodies of thoughts on it, that it is either dead in the water, so to speak, or that it is biding it’s time, also so to speak. Only time will tell who is correct. I am with the latter camp, myself. I think it will move again, in a big way, but I think it will be quite some time before it happens, perhaps 100+ years.

  7. boballab says:

    @Catherine

    I’m with you on the NMSZ. Until the plates stop moving no fault zone can go “dead” IMHO. To me it’s like those dead volcanoes that keep coming back to life (Zombie Volcanoes = Zomcanoes?). Pinatubo was a classic example of that, which I had a ringside seat for.

    @EM

    Don’t get happy about that. It’s just the other flank of the pincer attack moving along the Aleutians and then down the coast.

  8. E.M.Smith says:

    Aaiiiii! I’m in the Battle Of The Bulge! ;-)

    And I find it fascinating how you can see the forces taking the Hayward / Calaveras fault zone path rather than moving up the San Andreas as they split near San Jose…

  9. Pingback: TWAWKI » Deadly hurricane twins

  10. E.M.Smith says:

    I have to agree on the NMSZ. It’s just a giant ‘join’ in the middle of the continent where two old chunks of a prior continent got slammed together. Not a weld line. So the weakness remains just waiting for an off center force to give it a reason to slip.

    And dead? No way. Dead would be somewhere like Casper Wyoming or the middle of Canada… Or not ;-)

    Magnitude 4.0 – WYOMING

    This event has been reviewed by a seismologist.
    Magnitude 4.0
    Date-Time
    Sunday, September 12, 2010 at 22:20:30 UTC
    Sunday, September 12, 2010 at 04:20:30 PM at epicenter
    Time of Earthquake in other Time Zones
    Location 43.121°N, 110.760°W
    Depth 6.9 km (4.3 miles) (poorly constrained)
    Region WYOMING
    Distances
    40 km (25 miles) S of Jackson, Wyoming
    45 km (30 miles) NNE of Afton, Wyoming
    80 km (50 miles) WNW of Pinedale, Wyoming
    540 km (335 miles) WNW of CHEYENNE, Wyoming
    Location Uncertainty
    horizontal +/- 9.8 km (6.1 miles); depth +/- 14.2 km (8.8 miles)
    Parameters
    NST=105, Nph=111, Dmin=27.8 km, Rmss=0.5 sec, Gp= 36°,
    M-type=local magnitude (ML), Version=6
    Source USGS NEIC (WDCS-D)
    Event ID us2010bccu

    Magnitude 4.0 – NORTHWEST TERRITORIES, CANADA

    This event has been reviewed by a seismologist.
    Magnitude 4.0
    Date-Time
    Monday, September 13, 2010 at 10:07:57 UTC
    Monday, September 13, 2010 at 04:07:57 AM at epicenter
    Time of Earthquake in other Time Zones
    Location
    62.645°N, 125.525°W
    Depth 5 km (3.1 miles) set by location program
    Region NORTHWEST TERRITORIES, CANADA
    Distances
    120 km (75 miles) SW of Wrigley, Northwest Territories, Canada
    235 km (145 miles) WNW of Fort Simpson, NW Territories, Canada
    290 km (180 miles) NNW of Fort Liard, NW Territories, Canada
    575 km (355 miles) W of YELLOWKNIFE, NW Territories, Canada
    Location Uncertainty
    horizontal +/- 16.2 km (10.1 miles); depth fixed by location program
    Parameters
    NST= 22, Nph= 22, Dmin=531.1 km, Rmss=1.28 sec, Gp=169°,
    M-type=body wave magnitude (Mb), Version=7
    Source USGS NEIC (WDCS-D)
    Event ID us2010bdcm

  11. Catherine Clark says:

    Except the NMSZ isn’t a “join” per se, but a failed rift in the continent. That’s why there are few, if any, surface ruptures from the 1811-1812 EQ’s. The ancient volcanism is so deeply buried under centuries of silt and other sedimentary layers. No, the CSZ is the one that makes me very uneasy.

  12. PhilJourdan says:

    But what is “normal”. I guess having lived in California for so many years (and getting the 4.x-5.x quakes regularly), I am not sure if there is cause for concern – or to just stop shaking my own martini and let mother nature do it.

  13. Catherine Clark says:

    Bob,
    You had a ringside seat for Pinatubo?!!!?! OM Gosh, that must have been incredible! Scary! I saw video of the eruption and it gave me the willies. Couldn’t believe all the lahar’s and all that was going on! I don’t think geologists ever wrote it off as dead; I think it was classified as dormant. Volcanos that only erupt every 500+ years or so are generally quite explosive, as was demonstrated with Pinatubo, among others. I don’t think a ringside seat at Pinatubo would be an uplifting experience, LOL. More like the scariest thing I can think of, and also one of the most fascinating!

  14. boballab says:

    @ Catherine

    No they had it initially as extinct and when it re-awoke it shocked them. Matter of fact if you watch the documentary “In the Path of Killer Volcano”, the USGS scientists admit they had no knowledge of what Pinatubo could do. They tell about how when flying over Katmai and seeing the ash deposits from it, and knowing how explosive it was, then seeing Pinatubo’s old deposits they got very concerned: Pinatubo’s were larger then Katmai’s.

    At the time I was stationed at Subic Bay Naval Station and on June 8th I was heading up to Clark Air Force base to attended a week long school on Microwave comms. The road from Olongapo thru Angeles to the base went with in about 8 miles of the volcano and it was doing a small eruption when we went by.

    Well they canceled the class and I spent from then until June 14th working 12 hr shifts installing back up comm circuits incase Pinatubo took out Clark. When i got off shift on the morning of the 14th, knowing we were done and having the 15th off I went to bed around 5pm. When I woke up it was pitch black and the power was out in the apartment I rented out in the town (I was living with my then fiancée now wife). Now I wear glasses so I had them off so when I clicked the light button on my watch and look at it I saw it read 9:00 and I laid back down. however something was nagging me and I re lit the watch and found it was 9:00 AM.

    here is a link to a site that has pictures taken on the base after the eruption:
    http://www.subicbaypi.com/subic_pinatubo_base.htm

    The next link is to a picture in front of the barracks that I hardly ever stayed at:
    http://www.subicbaypi.com/sub_desbase022.htm

    The next link is to a picture of a car that crashed during the eruption (and the passing of a typhoon at the same time). I saw that when driving my commands XO around:
    http://www.subicbaypi.com/sub_desbase021.htm

  15. Chuckles says:

    It must be serious (or it’s budget approval time), the locals here are getting into the act –

    http://www.telegraph.co.uk/science/science-news/8007015/Deadly-earthquake-could-strike-Britain-any-time.html

    :)

  16. Catherine Clark says:

    I own the documentary you speak of. I guess I missed the part about it being extinct! I do remember their going over Katmai and how Pinatubo’s were more extensive. I remember their concern. Of course, with a volcano that only erupts every few centuries no one would have any idea what to expect unless they inspected the topography around the volcano. That is what got the geologist so concerned – flying into the area and seeing the evidence all around of ash and flow deposits. I can’t even begin to imagine what it was like to be there!

  17. boballab says:

    @Catherine

    The part about it being extinct wasn’t in the movie, just the part about them saying they had nothing on it. However since I was living in the Philippines I got to see the Philippine newscasts with the interviews of the head of PhilVolcs and he said it was extinct. The part about USGS having nothing on this Volcano is troubling as I will show below.

    You have to keep a few things in mind when dealing with anything in the Philippines.

    1. From 1900-1941 the US controlled it as a territory and had bases near that area since 1900. US scientists of all types starting in the 1920’s crawled around the jungles and spoken to the indigenous peoples. They knew there was a volcano there but the indigenous people had no oral tradition of eruptions. They went tromping around saw no thermal or felt any seismic activity and said “it’s dead Jim”.

    2. From 41-45 the Japanese controlled the islands, and no scientific groups went into there but US led guerrilla bands operated through out the area. Neither them nor the Japanese (Who know a thing or two about Volcanoes) archived any type of volcanic activity in that area.

    3. After 1945 the Philippines was granted independence but the US kept multiple bases there including the big bases of Subic Bay and Clark Air Force base. We are now in the time of reliable aviation and rotary flight. From 1945 to 1991 there had been multiple flights over the Volcano by both US and Philippine authorities. Matter of fact Pintubo was so far off the grid to volcanologists it wasn’t even watched. No seismographs. No checks by Volcanologists or Geologists. All attention was focused on Mayon. No sign of activity on or near the mountain was observed or reported so it stayed on the “it’s dead Jim” list.

    Then one day a couple of loincloth covered tribesman wondered in from the bush (Yes there is still headhunters living there, one such tribe resided on the Subic Bay base, luckily they liked Americans and taught our Marines , Spec Ops and Pilots how to survive in a jungle) and ran around Angeles city telling people about how the Mountain was mad and showing its displeasure by releasing a very bad smelling and white gas: Sulpher. At first no one listened, but luckily someone did and the Philippine Government sent out a volcanologist to see what was going on. When the tribesman took him out to the mountain he found active steam vents and he went back and got a seismograph. He brought it back to the mountain and found out just how active things were. That was in March 1991 and finally got PhilVolcs off there butts to watch the thing.

    Then in May they really got concerned and needed the help of the USAF to watch the thing. From there a request went into USGS for help and they sent out a team.

    Most of this is not in the popular or written accounts made after the fact but as I said I lived it and got to watch the story unfold. So as Paul Harvey used to say: “Now you know the rest of the story”.

    You have to search around to find the details of all this on the Web:

    In mid-March 1991, villagers around Mount Pinatubo began feeling earthquakes and vulcanologists began to study the mountain.

    http://geography.about.com/od/globalproblemsandissues/a/pinatubo.htm

    Steam
    On April 2, 1991, a hydrothermal explosion at Pinatubo’s crater interrupted its 450 years of slumber. Rumbling sounds were heard as steam clouds and a small amount of ash were ejected from several active vents, shooting them to heights ranging from 500 to 800 meters.

    Quakes (or Seismicity)
    Three days later, in a hastily installed temporary seismic station at Sitio Yamut, scientists recorded 223 high frequency volcanic quakes (HFVQ) during its first 24 hours of operation. Then, for two months from April 6 to June 6, the seismograph’s daily count varied from a minimum of 26 to a maximum of 178 incidents of HFVQs. The occurrence of HFVQs indicate fracturing of rocks and movement of fault structures due to the pressure exerted by intruding magma and escaping steam.

    http://park.org/Philippines/pinatubo/page3.html

    Go to this link and look how they finally dated Pinatubo’s older eruptions: http://www.volcano.si.edu/world/volcano.cfm?vnum=0703-083&volpage=erupt

    The word ‘pinatubo’ means ‘grown’ in Tagalog and Sambal, which may suggest a knowledge of its previous eruption in about AD 1500, although there is no oral tradition among local people of earlier large eruptions. Pinatubo might instead mean a fertile place where crops can be made to grow. An indigenous group of people, the Aetas (also spelled as Ayta), had lived on the slopes of the volcano and in surrounding areas for several centuries, having fled the lowlands to escape persecution by the Spanish. They were a hunter-gatherer people who were extremely successful in surviving in the dense jungles of the area. These people also grew some staple crops such as wheat, barley, and rice.

    Before the catastrophic eruption of 1991, Pinatubo was an inconspicuous volcano, unknown to most people in the surrounding areas. Its summit was 1,745 m (5,725 ft) above sea level, but only about 600 m above nearby plains, and about 200 m higher than surrounding peaks, which largely obscured it from view.

    Aetas living near Pinatubo worship the creator named Apo na Malyari who lives at the peak. According to them, this creator caused the 1991 eruption because of displeasure toward illegal loggers and Philippine National Oil Company executives who have drilled into the mountain for geothermal heat

    Although there seems to be no local knowledge of the previous large eruptions in the Pinatubo area, several Aeta residents reported in 1991 that their elders recalled small explosions in the past. Pinatubo was a known geothermal area before the 1991 eruption, and small steam explosions are quite common in such areas. It was only after volcanic activity began in 1991 that geologists studied the eruptive history of the region in any detail.

    On July 16, 1990, the major 1990 Luzon earthquake of magnitude 7.7 struck central Luzon. This was the largest earthquake recorded in 1990,[11][12] comparable in size to the 1906 San Francisco earthquake and the 2008 Sichuan earthquake. Its epicenter was in Rizal, Nueva Ecija municipality,[13] about 100 km northeast of Pinatubo, and faulted northwest-southeast through three provinces. It also followed the Philippine Fault System west as far as Baguio City, which was devastated, and is located about 80 km north-northeast of Pinatubo, leading volcanologists to speculate that it might ultimately have triggered the 1991 eruption, although this is impossible to prove conclusively. Two weeks after the earthquake, local residents reported steam coming from the volcano, but scientists who visited the mountain in response found only small landslides rather than any eruptive activity.

    On March 15, 1991, a succession of earthquakes was felt by villagers on the northwestern side of the volcano. Further earthquakes of increasing intensity were felt over the next two weeks, and it became clear some kind of volcanic activity was likely. On April 2, the volcano awoke, with phreatic eruptions occurring near the summit along a 1.5 km long fissure. Over the next few weeks, small eruptions continued, dusting the surrounding areas with Volcanic ash. Seismographs recorded hundreds of small earthquakes every day.

    Scientists immediately installed monitoring equipment and analyzed the volcano for clues as to its previous eruptive history. Radiocarbon dating of charcoal found in old volcanic deposits revealed three major explosive eruptions in recent millennia, about 5500, 3500 and 500 years ago. Geological mapping showed that much of the surrounding plains were formed by lahar deposits from previous eruptions.

    http://en.wikipedia.org/wiki/Mount_Pinatubo

    It was Pinatubo that got Volcanologists to stop being complacent about “extinct” Volcanoes, and actually place monitoring equipment on them. They found that most of the “extinct” volcanoes were not so extinct, they just didn’t show there activity to the naked eye.

  18. boballab says:

    Forgot to put this into the last comment.

    USGS as an organization dropped the ball big time on that Volcano. They knew it was there, they knew it was close to two of the US largest Military installations.

    Over that long history of the US and the Philippines if USGS wanted to put monitoring equipment to watch the thing, it would have happened.

    They got complacent of that thing and it became out of sight, out of mind.

    Now OTOH the team that USGS sent in May of 91 really pulled alot of peoples bacon out of the fire. They made a very accurate call, with very little information and under extreme pressure. If they blew it, alot more people would have died including lots of US servicemen and their dependents.

  19. Catherine Clark says:

    Thanks for the great links to Pinatubo activity! I remember the 7.7 EQ and yes, it might have been a factor in the eruption. I just finished reading a fascinating paper about EQ’s affecting eruptions of volcanos nearby and it was definitely though-provoking!

    It brought to mind St. Helens (I grew up in the PNW) and it’s eruptions. I remember that I had been reading about the explosive history of St. Helens and a couple of historical eruptions about 2 years previous and had mentioned to my dad that they should be watching for mudflows that might have an impact on the Columbia River and he scoffed at that; he couldn’t imagine that, but that is exactly what happened. I remember it was kind of a triumph in that I had predicted it based on my research/reading of the volcanos history.

    Rainier is dormant – no one would ever make the mistake of calling it extinct! At least I would hope not! It is wired to the utmost, LOL! When they built all those surrounding communities in the lowlands around the volcano, they never knew they were building on ancient (some not so ancient) lahars.

  20. P.G. Sharrow says:

    We live on the southwest flank of the Mt. Tehama cauldara atop of 80 feet of lahar and 300 feet of cemented ash. At least it is a few million years old, I think.
    Mt Lassen is on the northeast edge of the cauldara. There has been quite a bit of small quake activity on the northwest flank this year near Mineral at a small cone about 25 miles north of us. Maybe some connection to Mt. Shasta ? About 20 years ago USGS discovered a “new” 6 foot bulge to the east of Mt Shasta. Wonder what that was all about? Out toward Medician Lake and the Devils Garden, all very recent activity areas.

  21. E.M.Smith says:

    Let us know if it starts to rumble and spit …

    As a kid I used to go about 4 miles east of town (just south of Chico) and look at the boulders tossed there by Mt. Lassen. The old folks would tell us kids about the eruption in 1914 or so and get us all interested in volcanoes. I’m still waiting for the next eruption…

  22. E.M.Smith says:

    Looks like a smallish one, but it’s in “the right place”… Wonder if it’s a ‘fore shock’…

    Magnitude 4.4 – OFF THE COAST OF OREGON
    2010 September 20 04:05:07 UTC

    This event has been reviewed by a seismologist.
    Magnitude 4.4
    Date-Time
    Monday, September 20, 2010 at 04:05:07 UTC
    Sunday, September 19, 2010 at 07:05:07 PM at epicenter
    Time of Earthquake in other Time Zones
    Location 44.709°N, 129.938°W
    Depth 10 km (6.2 miles) set by location program
    Region OFF THE COAST OF OREGON
    Distances
    465 km (290 miles) W of Newport, Oregon
    480 km (300 miles) WNW of Coos Bay, Oregon
    505 km (315 miles) WSW of Astoria, Oregon
    545 km (340 miles) W of SALEM, Oregon
    Location Uncertainty
    horizontal +/- 15.1 km (9.4 miles); depth fixed by location program
    Parameters
    NST= 33, Nph= 33, Dmin=495.7 km, Rmss=1.48 sec, Gp=198°,
    M-type=body wave magnitude (Mb), Version=6
    Source USGS NEIC (WDCS-D)
    Event ID us2010bkap

  23. Catherine Clark says:

    This is the 3rd or 4th smallish EQ in that location. I hope it doesn’t presage a larger EQ! I still wish the CSZ wasn’t so dang quiet! Really makes me nervous; I have so many friends and family out there! None on the coast, but many in Seattle, Renton, Federal Way, Tacoma, Puyallup, etc. I don’t like the physical history that has been literally dug up re the CSZ and what I have read gives me the willies!

  24. E.M.Smith says:

    We had bookends at each of the three line join points, now one mid-one-side. Looks to me like it’s starting the early “wake up and creak the bones” prior to the big “POP the spine and shake off the fleas”… but that could still be a few decades away. Geology being so slow and all…

    Might want to ask your friends if they have a ‘quake kit’ and live in a wood frame single story home…

  25. Jeff Alberts says:

    I live on Whidbey Island north of Seattle. There are three ways onto the island, and two of them involve the already overloaded ferry system. The third is the Deception Pass Bridge, built in the 30’s. If a big quake takes it out, those of us without boats will be pretty screwed. Although, since we’ve got a Naval Air Station right here, I can always hope the Navy would airlift in supplies for the inhabitants (most of which are former/retired Navy.)

  26. E.M.Smith says:

    You could always just go fishing for lunch ;-)

  27. E.M.Smith says:

    Another One in Mexico:

    Magnitude 5.1 – OFFSHORE OAXACA, MEXICO
    2010 September 21 14:42:13 UTC

    This event has been reviewed by a seismologist.
    Magnitude 5.1
    Date-Time
    Tuesday, September 21, 2010 at 14:42:13 UTC
    Tuesday, September 21, 2010 at 09:42:13 AM at epicenter
    Time of Earthquake in other Time Zones
    Location 15.981°N, 94.890°W
    Depth 57.9 km (36.0 miles)
    Region OFFSHORE OAXACA, MEXICO
    Distances
    40 km (25 miles) ESE of Salina Cruz, Oaxaca, Mexico
    130 km (80 miles) W of Tonala, Chiapas, Mexico
    490 km (305 miles) WNW of GUATEMALA, Guatemala
    590 km (365 miles) SE of MEXICO CITY, D.F., Mexico
    Location Uncertainty
    horizontal +/- 11.1 km (6.9 miles); depth +/- 19.3 km (12.0 miles)
    Parameters
    NST= 44, Nph= 44, Dmin=843.1 km, Rmss=0.71 sec, Gp=169°,
    M-type=body wave magnitude (Mb), Version=6
    Source USGS NEIC (WDCS-D)
    Event ID us2010blav

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