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Tuesday, March 18, 2014

Shamrock Shake, Waverly Person, and the Moment Magnitude Scale

     Next week marks the 1/2 year anniversary of Partial Ellipsis of the Sun. Thanks for your support, humor, questions, and blog ideas. I've enjoyed reading every single comment.





     Yesterday's 4.4 magnitude earthquake in the Los Angeles area and a 5.0 magnitude earthquake in Iquique, Chile, prompted today's topic. I thought I would shake things up a bit after the "Shamrock Shake" and the quake in Chile that prompted the evacuation of 100,000 people.





   
      I am curious about whether you realize the U.S. Geological Survey, as well as most countries except Russia, no longer uses the Richter Scale as a measure of magnitude. The Moment Magnitude Scale, abbreviated MMS or Mw was developed in 1979 and more accurately reflects differences in energy released, particularly those above 7.0 on the old Richter Scale. Yet, the Richter Scale is more accurate for quakes of magnitude 3.5 and less.





       Both the Richter Scale and the Moment Magnitude Scale are calibrated similarly for medium sized quakes (3.5 - 7.0). The numbers for quakes higher than 7.0 are generally revised upward. The March 27, 1964, Alaskan earthquake is now a 9.2 (It was 8.4 on the Richter Scale.) Note the 33 foot scarp with dessicated, white marine organisms along the newly created flat portion:




     This 4 minute video about the Alaska quake was just released by the USGS to honor the big L anniversary:

         50Th Anniversary of 1964 Alaska Quake: USGS Video



     The May 22, 1960, Chilean earthquake, the largest seismic event recorded, has been recalibrated to a 9.5.





      Both scales take into account a logarithmic scale such that the increase from one step to the next is a 32 fold increase in energy and the increase from two steps apart is 1000 fold for those medium earthquakes. The MMS moves off much higher for quakes in the upper ranges. (See video at the end of this blog for more detail).

      Dr. Waverly Person, (yes, that's his real name) former Director of the USGS Earthquake Information Center here in CO, was responsible for converting quakes to the new scale, the one that hardly anyone knows. Just like our petrography friend, Dr. Nicol, that first name of Richter sticks. All the reports I read today included the Richter Scale.


      If you are interested in a spaghetti-based video explaining the differences between the scales, watch here:

               What happened to the Richter Scale?


         The moral of this tale: get in there early in the name game!

         And be safe in a shake!

         Looking forward to p and s waves coming from you this week.


Seismically,


Word Woman (Scientific Steph)




     

      







41 comments:

  1. I've only felt 2 earthquakes in my life. The first, a 4.0 on October 19, 1985, in classic fashion felt like a truck going by outside, but not quite. The next one, a 5.8 on August 23, 2011, was unmistakably an earthquake (that's the one that damaged the Washington Monument). Neither was at all scary, or thrilling, but I was glad to have experienced them.

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    Replies
    1. I have yet to experience one...

      Councilmen in LA are already calling for a fracking investigation into the LA quake yesterday. Remember when CA earthquakes were just part of strike-slip faults and something you put up with to live in CA?

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  2. The USGS just issued a 28 volume report commemorating the 50 year anniversary of the March 27, 1964 Alaskan quake. Don't all rush at once to get your copy:

    http://www.usgs.gov/newsroom/article.asp?ID=3840#.UykzwBnnbqA

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  3. Blog blahs on this last day of winter. Maybe this news release from Hahvard will stir things up:

    DIRECT EVIDENCE OF COSMIC INFLATION

    If that doesn't do it we could turn to local news morning shows from Fox.



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    Replies
    1. Here's another angle on the same announcement.

      Fox? You mean the people who "accidentally" cut human evolution from the feed of the second episode of Cosmos?

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    2. Sweet video!

      Unbelievable about cutting human evolution from Cosmos. What do you think of the show so far? The first week didn't seem to have a definite focus.

      Our local Fox station had a little trouble showing images directly from a producer's twitter feed yesterday.

      Wow, not even skydiveboy will respond today...

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    3. Haven't had a chance to catch Cosmos yet. (Still working our way through House of Cards.... ) But I always love Neil DeGrasse Tyson. (See my Orange is the New Black quote from a few weeks back.)

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    4. NDGT is great. Hope he can pick a direction soon. I get wanting to touch on everything but it just doesn't work all that well. The images are pretty cool though.

      Looking forward to your thoughts when you see it, jan.

      Lego et al, have you watched it?

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    5. SS,
      Sorry, can't post much. Library kick you offlinbe after 30 minutes.
      lego

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    6. Thanks for stopping in, lego. Hope you get online soon...Sometimes the library will give you more time if you ask nicely ;-).

      Here is a dirt devil tumbleweed controlled burn from a week ago here in CO. Interesting stuff (since we seem to be wandering all over this week...):


      TUMBLEWEED FIRE

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    7. Looks dangerous. Not to mention CO2-releasing. I wonder if there's another way to remove flammable undergrowth without the negative effects & risks? And yeah, I know some pine cones need the heat to germinate. But, still....

      Finally watched Episode 1 of Cosmos last night. I could have done without the cheesy visuals & music, especially that spaceship. But I thought it set the stage well for a general audience. (But was a general audience watching?).

      I really liked the props to Sagan, and the way Tyson personalized the practice of science. And even though I've heard the story many times, I did get choked up when he told of the meeting in Cornell when he was in high school.

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    8. And pretty darn close to Denver...

      Yes, Neil's meeting with Carl Sagan is a touching, wonderful story. I wonder why Neal chose Harvard over Cornell. Could have been the weather and the isolated setting...

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    9. And, this touches on both MH370 and Neal deGrasse Tyson and Cosmos, among other things:

      http://www.msnbc.com/rachel-maddow-show/week-god-101

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    10. I didn't know this was a regular Rachel Maddow feature. I remember when it was Stephen Colbert's gig on The Daily Show. (And Steve Carrell's before that?)

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    11. Yes, some good stuff. I believe it was a SC to SC transition before that. . .

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    12. Those poorly drawn cartoons of famous scientists detract a great deal from Cosmos. When Neal is on screen, it's great.

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  4. http://www.huffingtonpost.com/2014/03/19/neil-degrasse-tyson_n_4990882.html

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    Replies
    1. Rats! They pulled the video due to copyright issues. Sounded like a good one though, Paul.

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    2. Like energy and matter, nothing on the Internet can truly be destroyed:

      http://dailypicksandflicks.com/2014/03/18/neil-degrasse-tyson-and-9-year-old-kid-debate-asteroid-destruction-video/

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    3. Thanks. Jacob and Neal were great together!

      Wonder why HuffPo had the copyright issue.

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    4. Maybe so. Arianna Huffington could spread a little of that wealth around by paying more than a minimal crew of writers and editors...

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  5. Getting back to MH370, it occurred to me yesterday that if something like Christopher Goodfellow's scenario is correct (and there are strong arguments against that), we will likely never know what happened on the flight. The black boxes record only the final 2 hours of flight. If the cockpit crew was incapacitated hours earlier, the flight data recorder would have recorded pretty much nothing of interest, just straight and level flight with no control inputs, and nothing on the cockpit voice recorder (except maybe frantic banging on the door) until alarms for low fuel, engine flameout, and a final "Pull Up!" before the crash at the end. No hint of the problem that started it.

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    Replies
    1. Yeah, Goodfellow's scenario sure blew up (no pun intended) on the web. My question about black boxes: Why not have flight data available for longer than two hours? Why not for the entire flying range time of the aircraft?

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    2. I just rechecked, and it turns out I was mistaken. While cockpit voice recorders use only a 2-hour loop, it appears that flight data recorders store 17 - 25 hours of data. So we may be able to get useful info on MH370, if the FDR is ever recovered.

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    3. That makes more sense to me. I sure hope those families get the closure they need.

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    4. And speaking of FDR (but otherwise unrelated to anything we've been discussing), we visited the FDR Presidential Library & Museum in Hyde Park, NY, last weekend. More interesting that I'd thought it would be. The museum was particularly well done. Made me wistful for a much more progressive time in America.

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    5. I was there a while ago and it was well done.

      And on another unrelated topic, the kindergarteners and I experimented with the "dominant paw-ness" of my dog, Maizie, by hiding treats under a pillow. And we then experimented with our own dominant hands...It was a hoot! Although "I'd give my right arm to be ambidextrous" went over better with the teacher than the kids...

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    6. I like it. I'm reminded of studies that show that apes, despite generally superior intelligence, are much worse than dogs at responding to human gaze and gestures, You can train a dog to find a treat you've hidden by just looking at the hiding spot, but chimps won't pick up on that.

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    7. BTW, Maizie is decidedly left-pawed. Kids were 12 right-hand dominant and 2 left-hand dominant.

      Dogs are the best! I'd bet their "Emotional Intelligence" is well above that of apes...

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  6. Speaking of earthquakes and women in science, WW, do you happen to know Evelyn Roeloffs, a geophysicist with the USGS?

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    1. jan, I do not know Evelyn Roeloffs though I have heard her name. I did GIS work with Lynn (Marilyn) Tennyson at the USGS. My other big claim to fame was being CO Governor John Hickenlooper's Managing Editor when he was Associate Editor for The Mountain Geologist.

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    2. Friend of a friend. She was the geologist with rocks in her backpack that I mentioned hiking with.

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    3. Ah, yes, rocks in the backpack~~a common affliction among every geologist I know.

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  7. Replies
    1. Maybe a faith-based answer. OK, that may be too harsh, but as presented, it seems to me a likely answer, rather than a conclusive one. Also, it says nothing about what caused the plane to end up where it may have ended up.

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  8. It does seem likely, just not conclusive at all.

    Something's not adding up.

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  9. More on the Alaska 1964 earthquake and tsunami:


    http://www.usgs.gov/blogs/features/usgs_top_story/the-1964-great-alaska-earthquake-tsunami/

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  10. More Richter scale on today's 8.0 Chilean quake and tsunami:

    http://www.cbc.ca/m/news/#!/content/1.2594894

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    Replies
    1. 7.4 and 7.8 aftershocks within the past hour or so. . .

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