There are always a gajillion different things going on at AGU, to the point where it's overwhelming to consider all of it. When I considered the categories that are most likely to relate to my work (Seismology and Tectonophysics, also sometimes Union), Tuesday seemed to be the day that had the least subject matter related to my own work. That made it a logical day to catch up with people and discuss projects and research - not to mention, it was a good day to do my stint as the representative at the UCR booth in the exhibition hall.
The first thing I did was head over to the Southern California Earthquake Center booth to set up a time to discuss a project I've been working on with them. I know I've mentioned this project rather evasively thus far, and while I can't give lots and lots of details yet because it hasn't been released yet, I will say that it's an earthquake awareness comic book called "Faults of California." The illustrations were finished this summer, but we're working on a education module to go with it. We ended up deciding to meet about this on Wednesday, but I stuck around the booth to help set up. This involved a scene of several people jumping up and down while shaking a poster tube, trying to dislodge a bunch of plate tectonics educational posters. Brings new meaning to the idea of "ShakeOut"!
I did go to a late morning session on earthquake early warning systems. Most of them were variations on the theme of using P-wave amplitude to make a guess at eventual magnitude, though they all suggested different ways to implement this. One took the approach of tracking sudden motions by GPS and reporting them that way (though, from talking to people at UCR who work with GPS, I would think this would take a while to process?). Another aimed to estimate the direction and extent of the eventual rupture by looking at wave directivity. This one was particularly interesting to me in that I think it would benefit from some sort of prior including possible rupture paths for faults with complex geometry. I hadn't ever thought that the kind of models I do could help with early warning, but apparently they could! The early warning session also included a talk on the Quake-Catcher Network, which I've blogged about on here before. This network uses the accelerometers built into laptop computers as basic earthquake ground motion sensors, and sends the timing and shaking data to a central network for consideration. When I first installed the software in early 2008, QCN was still in alpha-test mode. It currently has expanded to over a thousand users across the globe. (And I'd encourage you all to check it out and add to the member count!)
I spent the entire afternoon at the UCR booth in the Academic Showcase part of the exhibit hall. Traffic was relatively slow to the booth (and it probably didn't help that we were between Yale and Virginia Tech), but there were a few prospective students who signed the mailing list. I also got a lot of questions more pertinent to the Environmental Sciences department (which is not the same as the Earth Sciences department at UCR), and a lot of inquiries about "Where is Riverside, anyway?" (when I answered that one, it was often followed by, "Wow, is it really hot?"). I assure you, visitors and questioners, that our department is worth another look. Being in the desert and 100+ degree heat does nothing to hinder the good work coming out of UCR.
Showing posts with label qcn. Show all posts
Showing posts with label qcn. Show all posts
Wednesday, December 16, 2009
Thursday, January 8, 2009
4.5 in the Inland Empire
There was a magnitude 4.5 earthquake in San Bernardino tonight, with a depth of 8 miles and a fault plane solution that suggests strike-slip, but not the San Jacinto or the San Andreas.
I would have liked to have live-blogged this from the epicentral region, but my iPod didn't want to pick up the coffeeshop's internet, so I had to drive home. But when I say "epicentral region," I mean it. I was about four and a half miles from the epicenter when the quake it. I've been closer to them before, but those were all much smaller - as in, 2.6. 4.5 was a whole different kind of experience this close.
I was at a coffeeshop in Redlands with some friends; we were all sitting at a table outside. I felt a little wiggle, and apparently so did a few of the others, since someone said, "Hey, is that an earthquake?" There was time for some confused looks before the shaking got stronger, and the general response was, "Oh yeah, earthquake!" It then proceeded to get even stronger for a little bit, before fading. I'd say that, on the whole, it could have been up to fifteen seconds of shaking. The thing that really excited me, though, was feeling three wave arrivals. I know I felt S and Surface for Chino Hills in July, but I wouldn't have felt P in a car with good shocks. Sitting outside, though, there's no such damping. There were definitely three different jolts, each stronger than the last. This one was a really good ride, and it made my day.
I'm also really curious to see how well QCN did in terms of picking this one up, since many more people are running the software than there were for Chino Hills. I know that my laptop picked up a good waveform for that one, and I'm hoping it did for this one as well, since the computer was by itself and not being used at the time of the quake. There isn't a way for me to scroll back that far through my computer's own records to see if I picked it up, so I'm guessing I won't know until tomorrow, at least, providing that those of us who picked up the signal get an email about it, like last time. I'll post on here about it if I do find out.
There was also a magnitude 3.3 aftershock about an hour after the mainshock, but I didn't feel it because I was in the car. I think I was actually going over the dreaded 10-215 interchange (which goes directly over the San Jacinto Fault) at the time, so it's really good that I didn't feel it. I admit that, every time I go over that interchange, I think, "Not now, San Jacinto, not now!" Feeling a shake on that overpass would probably break my brain.
I would have liked to have live-blogged this from the epicentral region, but my iPod didn't want to pick up the coffeeshop's internet, so I had to drive home. But when I say "epicentral region," I mean it. I was about four and a half miles from the epicenter when the quake it. I've been closer to them before, but those were all much smaller - as in, 2.6. 4.5 was a whole different kind of experience this close.
I was at a coffeeshop in Redlands with some friends; we were all sitting at a table outside. I felt a little wiggle, and apparently so did a few of the others, since someone said, "Hey, is that an earthquake?" There was time for some confused looks before the shaking got stronger, and the general response was, "Oh yeah, earthquake!" It then proceeded to get even stronger for a little bit, before fading. I'd say that, on the whole, it could have been up to fifteen seconds of shaking. The thing that really excited me, though, was feeling three wave arrivals. I know I felt S and Surface for Chino Hills in July, but I wouldn't have felt P in a car with good shocks. Sitting outside, though, there's no such damping. There were definitely three different jolts, each stronger than the last. This one was a really good ride, and it made my day.
I'm also really curious to see how well QCN did in terms of picking this one up, since many more people are running the software than there were for Chino Hills. I know that my laptop picked up a good waveform for that one, and I'm hoping it did for this one as well, since the computer was by itself and not being used at the time of the quake. There isn't a way for me to scroll back that far through my computer's own records to see if I picked it up, so I'm guessing I won't know until tomorrow, at least, providing that those of us who picked up the signal get an email about it, like last time. I'll post on here about it if I do find out.
There was also a magnitude 3.3 aftershock about an hour after the mainshock, but I didn't feel it because I was in the car. I think I was actually going over the dreaded 10-215 interchange (which goes directly over the San Jacinto Fault) at the time, so it's really good that I didn't feel it. I admit that, every time I go over that interchange, I think, "Not now, San Jacinto, not now!" Feeling a shake on that overpass would probably break my brain.
Tuesday, August 5, 2008
Last Tuesday's 5.4
Wow, this is something I should've written about exactly a week ago! It may not suffice to say that I was so giddily excited about the earthquake that I couldn't sit down at my computer to spew text onto a single site for more than a few minutes, but yeah. I'm a week late - but I'm still excited about it! This was the largest earthquake I've felt thus far, and that was made more amusing by the fact that, six days earlier, I felt my smallest quake, a 2.6 on the San Jacinto Fault.
I was in the car for this one. I'd just finished buying some food and toys for the faultcats at Petsmart, and was going about 25 mph down the street. I saw that the light was red, so I went for the brake. As soon as my foot hit the pedal, the car wobbled from side to side. Since the wobbling was not yet continuous, I worried something was wrong with the brakes, so I started to push the button that brings up the display that supposedly tells me when something is wrong with the car. (I love how my car tells me when it needs work. Not that it has needed work yet. But!) As I was pushing the button, though, the side to side motion returned in an intensified state. A look around confirmed that street signs and trees were also all wobbly, and that was all the confirmation I needed for the cause of my car's wiggle. The light turned green at this point, so I turned the corner and went on my way, anxious to get home and check the USGS site for a magnitude and location. I figured it had to be at least in the mid 4s, since a car's shocks absorb smaller vibrations. I certainly did not expect 5.6, as the USGS text message said, though! By the time I got to the Did You Feel It page on the website, it was saying 5.8, and my jaw was further unhinging. Except by the time I finished filling out the form, it was down to 5.4. I admittedly felt a bit gipped out of that extra 0.4, but still was excited to the point of being giddy about the whole thing.
Now that I think about the feeling of it in the car, I'm sure I felt two separate wave arrivals. My initial thought was that these were P and S arrivals, but after talking about it with people in the lab at school, it doesn't make sense that the smaller vertical P-wave would be noticeable in a car with good shocks, at least not in a quake that wasn't epically huge. More likely, these were the arrivals of the S wave and the surface waves. Friends of mine who were stationary and in buildings at the time said they felt three separate pulses.
My computer, so it seems, also got a really good ride out of this earthquake. This was the first event of any significance since the Quake Catcher Network alpha test went online in the winter, and thus the first really solid test. According to the event-specific site, there were a bunch of laptops triggered, but three of them had clean and clear records. This says, of course, that more computers involved will mean more clean records on the whole, but it's also good for determining what might make noise on the record, and how to clean it up further.
That QCN worked so well is exciting in and of itself, and I was already giddy from the quake without the QCN factor, so imagine my excitement when I received an email on 30 July from the person heading the Stanford branch of QCN, stating that one of those three spotless clear records came from my own little laptop! That I got a decent recording makes sense - the computer was closed in a room where the cats could not get to it, and thus was only moved by the earthquake. But I have to say I am probably inordinately proud of my computer, since it is a machine and all, for making the top three.
The middle four seismograms came from my computer!
Since last Tuesday, there have been a bunch of little aftershocks that I did not feel. There was, however, a 3.0 on that part of the San Jacinto closest to my building. People outside of the building were definitely talking about it, but it seems like none of them reported it to the USGS, since there's no Did You Feel It map. I know I'm not the only one who felt it! Bah!
I was in the car for this one. I'd just finished buying some food and toys for the faultcats at Petsmart, and was going about 25 mph down the street. I saw that the light was red, so I went for the brake. As soon as my foot hit the pedal, the car wobbled from side to side. Since the wobbling was not yet continuous, I worried something was wrong with the brakes, so I started to push the button that brings up the display that supposedly tells me when something is wrong with the car. (I love how my car tells me when it needs work. Not that it has needed work yet. But!) As I was pushing the button, though, the side to side motion returned in an intensified state. A look around confirmed that street signs and trees were also all wobbly, and that was all the confirmation I needed for the cause of my car's wiggle. The light turned green at this point, so I turned the corner and went on my way, anxious to get home and check the USGS site for a magnitude and location. I figured it had to be at least in the mid 4s, since a car's shocks absorb smaller vibrations. I certainly did not expect 5.6, as the USGS text message said, though! By the time I got to the Did You Feel It page on the website, it was saying 5.8, and my jaw was further unhinging. Except by the time I finished filling out the form, it was down to 5.4. I admittedly felt a bit gipped out of that extra 0.4, but still was excited to the point of being giddy about the whole thing.
Now that I think about the feeling of it in the car, I'm sure I felt two separate wave arrivals. My initial thought was that these were P and S arrivals, but after talking about it with people in the lab at school, it doesn't make sense that the smaller vertical P-wave would be noticeable in a car with good shocks, at least not in a quake that wasn't epically huge. More likely, these were the arrivals of the S wave and the surface waves. Friends of mine who were stationary and in buildings at the time said they felt three separate pulses.
My computer, so it seems, also got a really good ride out of this earthquake. This was the first event of any significance since the Quake Catcher Network alpha test went online in the winter, and thus the first really solid test. According to the event-specific site, there were a bunch of laptops triggered, but three of them had clean and clear records. This says, of course, that more computers involved will mean more clean records on the whole, but it's also good for determining what might make noise on the record, and how to clean it up further.
That QCN worked so well is exciting in and of itself, and I was already giddy from the quake without the QCN factor, so imagine my excitement when I received an email on 30 July from the person heading the Stanford branch of QCN, stating that one of those three spotless clear records came from my own little laptop! That I got a decent recording makes sense - the computer was closed in a room where the cats could not get to it, and thus was only moved by the earthquake. But I have to say I am probably inordinately proud of my computer, since it is a machine and all, for making the top three.
The middle four seismograms came from my computer!Since last Tuesday, there have been a bunch of little aftershocks that I did not feel. There was, however, a 3.0 on that part of the San Jacinto closest to my building. People outside of the building were definitely talking about it, but it seems like none of them reported it to the USGS, since there's no Did You Feel It map. I know I'm not the only one who felt it! Bah!
Tuesday, March 11, 2008
Shake Up != Wake Up
The Inland Empire apparently had three magnitude 3+ earthquakes on Sunday night. I felt none of them, which I find disappointing, since it's been almost three months since the last one I noticed. I'm sure I would have noticed them if I had been awake, since I tend to notice even the 2.9s, and since I felt two 3.9s from the same area (near Devore) in May. I literally just missed these three, though - I went to sleep fifteen minutes before they happened, and was too exhausted to be woken up, even by the magnitude 4.0. I suppose that finishing the draft of my thesis on Sunday should have been satisfaction enough to make me feel less disappointed about missing these, but such is not the case.
I'm particularly disappointed, though, that my computer wasn't running to catch these. I've been alpha testing the Quake-Catcher Network software since the beginning of February, and I have not yet had a chance to see how it picks up a genuine earthquake or three (as opposed to the motions caused by cats named after faults rocketing around my apartment). Also, by having one less of the alpha test computers running at the time (not that I know how many were running), that's less data with which to test the collecting and analyzing part of the QCN software. I know one computer isn't going to screw it up all by itself, but since I'm trying to help test this thing, I know my computer will be more useful if it was turned on to pick up quakes, even if I'm not awake to feel them. I'm hesitant to leave the computer running 24/7 for the sake of my hard drive, but I may have to just not think about that.
Looking at this little sequence (4.0, 3.4, 3.2) and one from 23 May 2007 (3.9, 3.9), both centered in pretty much the same place near Devore, I have to wonder if there's a small asperity in the fault there. In both sequences, all of the events happened within a couple of minutes - if not seconds - of each other, without many aftershocks later. I admittedly don't know enough about fault mechanics yet to tell whether or not my thought here can hold any water, but it seems at least possible that in these sets of events, the rupture could start, be briefly paused by the little asperity, then continue after stress makes the asperity give way. Does this actually make sense? Now that there have been two little sets of events there, I plan on reading more about that aspect of fault mechanics once I'm done with my comprehensive exams.
I'm particularly disappointed, though, that my computer wasn't running to catch these. I've been alpha testing the Quake-Catcher Network software since the beginning of February, and I have not yet had a chance to see how it picks up a genuine earthquake or three (as opposed to the motions caused by cats named after faults rocketing around my apartment). Also, by having one less of the alpha test computers running at the time (not that I know how many were running), that's less data with which to test the collecting and analyzing part of the QCN software. I know one computer isn't going to screw it up all by itself, but since I'm trying to help test this thing, I know my computer will be more useful if it was turned on to pick up quakes, even if I'm not awake to feel them. I'm hesitant to leave the computer running 24/7 for the sake of my hard drive, but I may have to just not think about that.
Looking at this little sequence (4.0, 3.4, 3.2) and one from 23 May 2007 (3.9, 3.9), both centered in pretty much the same place near Devore, I have to wonder if there's a small asperity in the fault there. In both sequences, all of the events happened within a couple of minutes - if not seconds - of each other, without many aftershocks later. I admittedly don't know enough about fault mechanics yet to tell whether or not my thought here can hold any water, but it seems at least possible that in these sets of events, the rupture could start, be briefly paused by the little asperity, then continue after stress makes the asperity give way. Does this actually make sense? Now that there have been two little sets of events there, I plan on reading more about that aspect of fault mechanics once I'm done with my comprehensive exams.
Sunday, January 13, 2008
On laptop accelerometers
I'm afraid I can't remember in whose blog I saw a link to SeisMac, a piece of freeware that uses the accelerometer built in to Intel Mac laptops to "convert" the computer into a seismometer. I do recall, though, how geekishly excited about the idea of that software I was, and then how disappointed I was when all of the times I tried to download it resulted in error messages. But now it seems that I'll be getting a chance to run some similar software on my MacBook after all.
It turns out that one of my professors is working on a project that aims to take laptop accelerometer readings beyond just a neat thing to watch on your screen, a fantastic procrastination tool, or a means for comparing the waveforms of actual earthquakes to the jolts caused by an overenthusiastic upstairs neighbor getting too involved in Wii Tennis (not that I have experience with such neighbors, of course not...). The software being developed for the Quake-Catcher Network will take that laptop accelerometer data and use it to help narrow in on epicenter locations, map shaking, and even give some degree of early warning for larger events. For people who only have desktops or whose laptop is too old to have a built in sensor, the project also involves development of a flash drive-sized USB accelerometer. (Even though my only computer is a laptop, I kind of want one of the USB accelerometers anyway, simply because the concept of carrying around seismic instruments on one's keychain makes me geekishly happy.)
The software is nearing the point where it will be tested by larger groups of people than just the developers, and even though I'm not technically admitted to the program here yet, I still get to help with that test. I'm sure I'll be writing more about how that goes once it gets started.
Another aspect I find particularly exciting about QCN is that there have been plans to use it for education from the get go. This should definitely show students (and non-geoscience-specific teachers) a side of California's chronic shakiness that they haven't seen before, which will hopefully in turn increase general awareness of how earthquakes happen and how seismic networks work, and maybe even prompt a few people to go on to formally study this stuff. I get the impression both from my own K-12 experience in northern Virginia and from talking with people in California that earth science is not considered by whoever comes up with the curriculim to be as serious of a science as biology, chemistry, or physics. In Virginia, there's an earth science unit in fifth grade science, and then a year-long basic geoscience class in high school (which, at the science and tech magnet high school I attended, was outright considered a joke class by most of the students); the other day, I was told that fifth grade is the only time some parts of California have earth science in the public school curriculum. I find it very strange that a state with little to no active geological processes would teach more than a state known for its earthquakes, mudslides, and fires, but at the same time, I'm not surprised based on some responses in the introductory geology class I took in university - only about a quarter of the class knew what the San Andreas Fault was (they'd heard the name, but couldn't explain what it actually is), never mind that it's only twelve miles from campus. Ideally, the curriculum will be expanded sooner than later to include more geoscience, but it seems to me that things like the QCN software used in schools will make the limited study that there is now more hands-on and meaningful.
It turns out that one of my professors is working on a project that aims to take laptop accelerometer readings beyond just a neat thing to watch on your screen, a fantastic procrastination tool, or a means for comparing the waveforms of actual earthquakes to the jolts caused by an overenthusiastic upstairs neighbor getting too involved in Wii Tennis (not that I have experience with such neighbors, of course not...). The software being developed for the Quake-Catcher Network will take that laptop accelerometer data and use it to help narrow in on epicenter locations, map shaking, and even give some degree of early warning for larger events. For people who only have desktops or whose laptop is too old to have a built in sensor, the project also involves development of a flash drive-sized USB accelerometer. (Even though my only computer is a laptop, I kind of want one of the USB accelerometers anyway, simply because the concept of carrying around seismic instruments on one's keychain makes me geekishly happy.)
The software is nearing the point where it will be tested by larger groups of people than just the developers, and even though I'm not technically admitted to the program here yet, I still get to help with that test. I'm sure I'll be writing more about how that goes once it gets started.
Another aspect I find particularly exciting about QCN is that there have been plans to use it for education from the get go. This should definitely show students (and non-geoscience-specific teachers) a side of California's chronic shakiness that they haven't seen before, which will hopefully in turn increase general awareness of how earthquakes happen and how seismic networks work, and maybe even prompt a few people to go on to formally study this stuff. I get the impression both from my own K-12 experience in northern Virginia and from talking with people in California that earth science is not considered by whoever comes up with the curriculim to be as serious of a science as biology, chemistry, or physics. In Virginia, there's an earth science unit in fifth grade science, and then a year-long basic geoscience class in high school (which, at the science and tech magnet high school I attended, was outright considered a joke class by most of the students); the other day, I was told that fifth grade is the only time some parts of California have earth science in the public school curriculum. I find it very strange that a state with little to no active geological processes would teach more than a state known for its earthquakes, mudslides, and fires, but at the same time, I'm not surprised based on some responses in the introductory geology class I took in university - only about a quarter of the class knew what the San Andreas Fault was (they'd heard the name, but couldn't explain what it actually is), never mind that it's only twelve miles from campus. Ideally, the curriculum will be expanded sooner than later to include more geoscience, but it seems to me that things like the QCN software used in schools will make the limited study that there is now more hands-on and meaningful.
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