Lockwood had to poke me that the Accretionary Wedge is stumbling back to its feet, but it was good timing for a poke, since the quarter has just ended, and I might actually have time to write things other than comments on the undergrad papers I've been grading. (More on my insane past quarter later.) Anyway, I was initially concerned that I wouldn't be able to think of a topic and come up with an even vaguely eloquent post by the end of the grace period for late entries.
And then I saw the actual topic. No need to brainstorm here! I'm sure that every single one of you who has followed my blog, sparse though it's been lately, knows where and when I'd take my time machine. My choice definitely does not, however, come from any sort of desire to watch the destruction of a major city and the combustion of thousands of lives within. The decision to set the time machine for San Francisco in April of 1906 comes from an intense interest in earthquakes as events and processes, a great love for the city in question, and a fascination with the development of the field of earthquake physics itself.
I'll admit right out that I am curious what it feels like to be in a M7.8 earthquake. So far, my personal experience maxes out at M5.4, which was entirely exciting and not at all terrifying in my book. I suspect M7.8 would be well past the boundary between excitement and fear, but I suppose I wouldn't be afraid of the idea of that fear if I were gearing up my time machine to experience it. Furthermore, the bigger quakes are the ones that get the most intensive study, and while my own models are currently producing things that, according to the length of the faults, might not top the mid-6 range, I'll eventually be dealing in 7-pointers, and I want to know what one is like. For this curiosity, a time machine is a preferable option to waiting for a real one, both because it eliminates the waiting to begin with, and also because it means we wouldn't need a new 7.8 to appease any seismologist who might have this same curiosity. Of course, there's bound to be another one sooner than later, geologically-speaking, but the longer we put the new one off, the more we come to know about the processes behind it, and the more we can prepare our cities and citizens. The old quake already did its damage, horrendous though it was.
And that brings me to another point - I would not want to be in San Francisco proper to experience this earthquake. Even if my time machine were to make me impervious to flying bricks and walls of flame, I'd still want to be waiting somewhere where I could see the fault rip its way down the peninsula. I once read an account of a woman in Idaho who watched a fault rip through her property. She described it as if the fault scarp were being painted across the landscape by a very fast brush. That definitely seems like some sort of juncture between fear and awe, and that is absolutely something I'd want to see. My odds of merely experiencing a non-anachronistic 7.8 are much higher than of me watching the fault break in the process of creating that 7.8. Once the rupture passed me by, however, I think I would want to get back to the City as fast as possible, to see what damage the earthquake alone did before the fires took over...and then I'd want to get back to safer ground quite quickly as well, to avoid being caught by the flames.
But I could see a surface rupture for so many other earthquakes. Why turn my time machine toward this one? That, I'll admit, comes from my feeling extremely attached to San Francisco - never mind that I've never lived there! In making my plans to jaunt back 103 years, I'd build in a little extra time before April 18th - maybe I'd show up at the beginning of the month - so that I could explore the old San Francisco before it got wiped off the map. There are plenty of words about it, but in describing the before and after case, whose prose wouldn't be biased by what they'd just gone through? And, of course, who would have known to take before photos, if they had no reason to expect an after? The 1906 earthquake might have been the first extensively photographed natural disaster, but pre-quake images are hard to come by. I'd want to spend time just wandering the place, as I explore places when I visit them now, getting to know the streets and buildings and characters as they were before their disruption. If I were allowed modern technology aside from my time machine, I might try to snap some photos. If not, I'd plan to blow through a sketchbook or two. I might also be tempted to try and get a seat (or, more likely, a place to stand in the gallery) at the infamous Metropolitan Opera showing of Bizet's Carmen on the evening of April 17th, both because of the infamy of the event, but also because I am still a music geek, switch of majors or not! I've never seen Carmen live, and were I to have the opportunity to see Caruso in it, well, that's an excitement I'd share with many of those 1906 San Franciscans. It might even be a strange way to lose track of my hindsight for a few hours - just so long as I was sure to get it back in time to get out to the fault trace!
When I say that I'd want to get out of danger in the City once the fire started, though, I do not mean I wish to zap myself immediately back to 2009. I would be willing to handle the discomfort of the survivor camps for the sake of historical and cultural understanding, but also as a way to wait for the less ominous aftermath. Before the 1906 earthquake, so very little was known about faults and how they work, and the still-nameless San Andreas Fault was thought to be a small discontinuity in rock type not extending beyond part of San Mateo County. I would love to get myself an in with the scientific community of the day and watch the progression from knowing nothing of the earthquake source to "do the earthquakes cause the faults, or do the faults cause the earthquakes?" to the oh-so-fundamental elastic rebound theory. I would be so excited to watch the faults of California get drawn in on the map for the first time, outlining mountain ranges, bounding geologic provinces, highlighting the network of hazard that we still strive to understand and mitigate today. And to be able to witness that while also observing the rebuilding of San Francisco...Definitely a time of wonder and excitement, even though it came out of tragedy.
I suppose that all means I'd be staying until 1910. A bit of an extended trip, in terms of humanity, but not even a blink in geologic time. And since a time machine could be set to return to the exact time and place from whence it came, it wouldn't even be a blink at all to the current world that includes my timeline. It might mean four years off from my research, but I'd come back from it with a closer connection to where what I'm doing comes from, both in terms of scientific roots and in terms of seeing first hand what these natural processes we study can do.
Thursday, June 18, 2009
Saturday, May 23, 2009
Seismology By Text Message
Now here's something I would have shoved everything else out of the agenda to post - had my internet not been down all week. It is so great having it back, let me tell you!
Anyway. I have a well-deserved reputation among my friends for being the geekiest of the geeky when it comes to earthquakes. As a result, a lot of my friends send me text messages whenever they feel a shake - even if it turns out to be a false alarm. After the quake in San Bernardino this January, I received messages from five different people within the first two minutes.
Some of those five people were out of town this past Sunday, but I still got two texts immediately following the M4.7 on the Newport-Inglewood Fault. I did feel the quake quite distinctly here in Riverside (it right after the conclusion of an orchestral and choral concert in which I'd played - if it had been five minutes sooner, it would have been a very interesting climax to the piece!); it started fairly sharply but was mostly rolling after that. It lasted long enough that I figured it was of a decent size but not particularly close.
The first text message came from a friend in Burbank. It came so soon after the shaking had stopped in Riverside that I immediately knew the source had to be closer to there than to here, since even the most intrepid of texters can't go that fast on tiny cell phone buttons. Within a minute, I got another message from a friend who lives down the street from me in Riverside. Both of them asked me whether or not I felt it, and how big it was. I told them I didn't know how big yet (and didn't find out until over an hour later, due to my stupid internet being down), but that I at least had some travel time information!
I also felt the M4.0 aftershock on Tuesday. It came during the midterm for the class I'm TAing, and while the urge was great to shout, "Did you feel that?" to an audience of several hundred, I didn't want to be a bad proctor and disrupt any test taking. When polled after everything was handed in, about half the class said they felt a wiggle. When I encouraged my discussion sections two days later to fill out the Did You Feel It? questionnaire, one student asked if the quake is why I'd practically skipped down the aisle of the lecture hall to talk excitedly with the professor. D'oh!
As I said, I have a reputation.
Anyway. I have a well-deserved reputation among my friends for being the geekiest of the geeky when it comes to earthquakes. As a result, a lot of my friends send me text messages whenever they feel a shake - even if it turns out to be a false alarm. After the quake in San Bernardino this January, I received messages from five different people within the first two minutes.
Some of those five people were out of town this past Sunday, but I still got two texts immediately following the M4.7 on the Newport-Inglewood Fault. I did feel the quake quite distinctly here in Riverside (it right after the conclusion of an orchestral and choral concert in which I'd played - if it had been five minutes sooner, it would have been a very interesting climax to the piece!); it started fairly sharply but was mostly rolling after that. It lasted long enough that I figured it was of a decent size but not particularly close.
The first text message came from a friend in Burbank. It came so soon after the shaking had stopped in Riverside that I immediately knew the source had to be closer to there than to here, since even the most intrepid of texters can't go that fast on tiny cell phone buttons. Within a minute, I got another message from a friend who lives down the street from me in Riverside. Both of them asked me whether or not I felt it, and how big it was. I told them I didn't know how big yet (and didn't find out until over an hour later, due to my stupid internet being down), but that I at least had some travel time information!
I also felt the M4.0 aftershock on Tuesday. It came during the midterm for the class I'm TAing, and while the urge was great to shout, "Did you feel that?" to an audience of several hundred, I didn't want to be a bad proctor and disrupt any test taking. When polled after everything was handed in, about half the class said they felt a wiggle. When I encouraged my discussion sections two days later to fill out the Did You Feel It? questionnaire, one student asked if the quake is why I'd practically skipped down the aisle of the lecture hall to talk excitedly with the professor. D'oh!
As I said, I have a reputation.
Sunday, May 17, 2009
A day of kinematic GPS
I really don't mean to be neglecting my blog (or neglecting commenting on your blogs) as much as I have been lately. It's mostly that, after the classes and the rehearsals and the homework and the grading, I put aside the papers and think only of sleep, rather than of spending more time at a screen writing things. I'm accumulating a rather lengthy To-Blog list, which, following Maria's lead> I think I'll have to make a summer break resolution (since New Year's is way too far off) to actually write up.
Anyway, though much of my time this quarter has been spent at a desk, the seminar I'm taking on tectonic geomorphology and quaternary field methods has served well to get me out and about. Many of our "trips" have been into the hills behind campus, mostly for funding reasons, but we have had a few larger outings. The most intensive one so far was when we went to Grass Valley in the San Bernardino Mountains to make a digital elevation map using kinematic GPS. (There was also a USGS/Caltech team out there using LiDAR to image some precariously balanced rocks, but we did not get to actively participate in this part of the work; we were mere observers.)
Grass Valley is located in the San Bernardino Mountains, not far from Lake Arrowhead. It falls into the region of highest possible threat of major earthquake ground motion in the state, due to its proximity to several major faults. The San Andreas Fault is 11 kilometers away, with several well-constrained paleoseismic sites within 20 km. The San Jacinto Fault is only a kilometer or two further away than the San Andreas; the north frontal thrust of the San Bernardino Mountains is about the same distance away to the north. The Cleghorn Fault runs directly through Grass Valley, though its activity isn't as well constrained; there's no current microseismicity, and no evidence of Holocene rupture.
The precariously balanced rock team was clearly there to try and constrain whether or not the worst case scenario of shaking according to the state hazard report had actually ever happened since those rocks became precarious to begin with. The focus of the class exercise, however, was more on a catchment containing a small system of drainages in the process of being captured by the Mojave River. Our goal was to use kinematic GPS to get a good picture of the area, which could then be used to better situate the precariously balanced rocks in the middle of the site.
Kinematic GPS is a method of relative measurement. Actual latitude/longitude figures don't come into play. All measurements are taken relative to a base station that gets set up somewhere central in the site, for the express purpose of kinematic GPS measurement. People then carry portable GPS antennae, either attached to a backpack or on a long pole, all over the area surrounding the base station. The goal is to go back and forth over all of the bumps and dips in topography - even though that does, of course, make for harder hiking at times - to make sure they show up in the DEM. The data has to be corrected for height of the person carrying the antenna (I was not, shockingly, the shortest one!) and for roughness of gait, but the corrections that need to be made can be gauged by having all of the antenna-carryers walk the same path before going their separate ways.
We spent a full afternoon tromping around the catchment, and the four of us managed to cross paths only a couple of times, hopefully implying that we didn't all cover the same ground. In my run-in with one of the professors, I was detailed to walk around the far edge of the site that hadn't yet been covered. I did so, but then I proceeded to overshoot the other edge of the site and get quite confused. I continued to walk through all of the (mostly-dry) drainages I could find for a while, but I started to get worried when I wasn't catching sight of the base station or the precariously balanced rocks. I definitely realized the irony of not having a clue where I was, despite having a GPS antenna strapped to my back, but dark humor wasn't going to get me out of the situation on its own. I did manage to work my way back to the road, then proceeded to go the wrong way on it for about half a mile before I noticed that I was wrong. It turns out I'd found the road only about 200 yards shy of the turnoff that lead straight to the base station. Ah well!
I haven't seen our DEM yet, though I'm told we covered a lot of ground, and I'm told that there was one antenna that went quite a bit further away than all the others did. One of the people in the class is doing all the processing as his final project for said class, so I may ask him if I can show off the results of our day in the field.
Anyway, though much of my time this quarter has been spent at a desk, the seminar I'm taking on tectonic geomorphology and quaternary field methods has served well to get me out and about. Many of our "trips" have been into the hills behind campus, mostly for funding reasons, but we have had a few larger outings. The most intensive one so far was when we went to Grass Valley in the San Bernardino Mountains to make a digital elevation map using kinematic GPS. (There was also a USGS/Caltech team out there using LiDAR to image some precariously balanced rocks, but we did not get to actively participate in this part of the work; we were mere observers.)
Grass Valley is located in the San Bernardino Mountains, not far from Lake Arrowhead. It falls into the region of highest possible threat of major earthquake ground motion in the state, due to its proximity to several major faults. The San Andreas Fault is 11 kilometers away, with several well-constrained paleoseismic sites within 20 km. The San Jacinto Fault is only a kilometer or two further away than the San Andreas; the north frontal thrust of the San Bernardino Mountains is about the same distance away to the north. The Cleghorn Fault runs directly through Grass Valley, though its activity isn't as well constrained; there's no current microseismicity, and no evidence of Holocene rupture.
The precariously balanced rock team was clearly there to try and constrain whether or not the worst case scenario of shaking according to the state hazard report had actually ever happened since those rocks became precarious to begin with. The focus of the class exercise, however, was more on a catchment containing a small system of drainages in the process of being captured by the Mojave River. Our goal was to use kinematic GPS to get a good picture of the area, which could then be used to better situate the precariously balanced rocks in the middle of the site.
Kinematic GPS is a method of relative measurement. Actual latitude/longitude figures don't come into play. All measurements are taken relative to a base station that gets set up somewhere central in the site, for the express purpose of kinematic GPS measurement. People then carry portable GPS antennae, either attached to a backpack or on a long pole, all over the area surrounding the base station. The goal is to go back and forth over all of the bumps and dips in topography - even though that does, of course, make for harder hiking at times - to make sure they show up in the DEM. The data has to be corrected for height of the person carrying the antenna (I was not, shockingly, the shortest one!) and for roughness of gait, but the corrections that need to be made can be gauged by having all of the antenna-carryers walk the same path before going their separate ways.
We spent a full afternoon tromping around the catchment, and the four of us managed to cross paths only a couple of times, hopefully implying that we didn't all cover the same ground. In my run-in with one of the professors, I was detailed to walk around the far edge of the site that hadn't yet been covered. I did so, but then I proceeded to overshoot the other edge of the site and get quite confused. I continued to walk through all of the (mostly-dry) drainages I could find for a while, but I started to get worried when I wasn't catching sight of the base station or the precariously balanced rocks. I definitely realized the irony of not having a clue where I was, despite having a GPS antenna strapped to my back, but dark humor wasn't going to get me out of the situation on its own. I did manage to work my way back to the road, then proceeded to go the wrong way on it for about half a mile before I noticed that I was wrong. It turns out I'd found the road only about 200 yards shy of the turnoff that lead straight to the base station. Ah well!
I haven't seen our DEM yet, though I'm told we covered a lot of ground, and I'm told that there was one antenna that went quite a bit further away than all the others did. One of the people in the class is doing all the processing as his final project for said class, so I may ask him if I can show off the results of our day in the field.
Saturday, April 18, 2009
San Francisco, April 18th, 5:12 AM
I got up at 4:30 all on my own this morning. I wanted to be up that early, because I wanted to be in a particular place exactly 42 minutes later. I am not normally a morning person, but it was surprisingly easy this time, because I was so excited about the whole thing. I had to admit that I was amused, though, that I was so very awake, in stark contrast with the people 103 years ago who were enjoying their last 42 minutes of sound unaware sleep.
Lotta's Fountain stands on a small traffic island in the middle of the intersection of Market, Kearny, and Geary. It's been there since 1875, a solid metal object impervious to what was thrown at it 31 years after its placement. As it was a prominent and resilient landmark at the time, people met there to keep track of each other through all the smoke and dust, and they continued to meet there in the following years to remember that morning when everything was so uncertain and nonsensical and terrible. As time went by and the proportion of survivors to their later-generation descendants skewed toward the latter, the meeting became more of an outright ceremony, a celebration of the City itself as a reborn entity just as much as a celebration of its people. I've written about this ceremony in several different stories and contexts, but this year, given that today is April 18th is Saturday, I jumped at the chance to actually be here for it.
Market Street was almost entirely empty at 5 AM, save for the knot of people surrounding the Fountain. There were easily over a hundred of us, possibly as many as two hundred. I was definitely one of the youngest people there, aside from some little kids that accompanied their parents, but on the whole, it was a very diverse crowd. Some seemed to be treating the whole affair very solemnly, apparently focused on the death and destruction that beset the City. Others took more of a festival approach, with flags and whistles and the letters SF emblazoned on pretty much every article of clothing they were wearing. Others still seemed to be largely there in support of the fire department. There was a small but particularly visible contingent of people dressed in period costume, pulling the predawn gathering into the realm of living history now that the event itself is so close to passing from genuine living memory into purely written and photographic records or secondhand accounts. And, this being San Francisco, there were a few particularly colorful characters that seemed to have no connection to the ceremony itself, but were taking the chance for an audience at which to praise Obama, support peace, denounce Proposition 8, and generally garner smiles in reaction. Regardless of the undoubtedly disparate reasons for everyone's interest in attending, it was exciting to see that this many people still care enough about what happened to drag themselves out of bed in the pitch black and collectively remember.
The ceremony proper began with a local senator, the chief of the fire department, the event organizers, and various other fire officials and VIPs of some sort pulling up in an old (though I don't think 103-old) red fire engine. They were followed by a huge shiny black car containing two of the remaining survivors, ages 107 and 105. The survivors were, apparently, interviewed, but I don't think they had a microphone, and I unfortunately couldn't hear a word they said. I'd hoped that I could get a chance to talk to them, but that didn't end up happening. I would have asked, "How do you think the City's view and treatment of these events has changed over the past 103 years?" Judging by the fact that a couple of other survivors died in the past year, this is a question I - or anyone else - might not get another chance to ask.
All the talk stopped at 5:12 AM. There was supposed to be a minute of silence, and that was so important that a few people in the crowd actually shouted at the senator that it was 5:11 and he had to stop talking in a few seconds. And there was actual silence, though not for the full minute; much of it was filled with bagpipes. While I appreciate the use of the instrument in solemn occasions, I would have preferred the actual silence, a long minute of expected lack of obvious noise from anywhere in the streets of such a normally-busy city, a distinct contrast from the minute of rumbling and cracking and growling we were commemorating.
After the silence, there were a few brief words from the senator, the fire chief, author James D'Alessandro, and the event organizer. They spoke of how wonderful it was that so many of us had gathered, how great a City this is to survive so much and come out so strong, how being prepared for the repeat is key to continuing to live here. The actual description of the events went unsaid, however; it didn't need to be described, since we all knew what it was that brought us all out there.
And then we sang. Or some of us did -- I felt awkward in the fact that I did not know the words and thus could not participate. The song in question is called simply "San Francisco," and comes from the 1930s movie of the same name. I didn't know the melody either, but the nondeliberate polytonality of the crowd's singing was still obvious to me. It didn't bother me; the lack of being in a single key didn't matter at all. Those who were singing sounded like they meant it enough to make up for those of us who were keeping quiet, and that sentiment meant far more than the actual music did.
In the end, a wreath was laid on the Fountain, the VIPs returned to their respective vehicles, and they took off in a motorcade of blazing sirens, met with claps and cheers. They did a lap around the block and then disappeared down Market, leaving the crowd to disperse. Some did so immediately, but others lingered longer. I remained there until about 6:30, engaged in conversation about Enrico Caruso, spaghetti western operas, which buildings remain that show signs of damage, what kind of geological mechanisms are responsible and how we understand them so much better now, even though there's still so much we don't know.
The light was right at 6:12 AM. There was no daylight savings time 103 years ago, so their 5:12 was an hour ahead of ours. As I'd read in so many period descriptions of that day, the light was the slightly greeny blue of dawn, with a narrow strip of warm yellow silhouetting the Ferry Building. That was, in a sense, the lightest it got on April 18th 1906; the rest of the day was engulfed in flame and smoke enough to obscure all sense of time of day. April 18th 2009 has been gorgeous and cloudless.
Lotta's Fountain stands on a small traffic island in the middle of the intersection of Market, Kearny, and Geary. It's been there since 1875, a solid metal object impervious to what was thrown at it 31 years after its placement. As it was a prominent and resilient landmark at the time, people met there to keep track of each other through all the smoke and dust, and they continued to meet there in the following years to remember that morning when everything was so uncertain and nonsensical and terrible. As time went by and the proportion of survivors to their later-generation descendants skewed toward the latter, the meeting became more of an outright ceremony, a celebration of the City itself as a reborn entity just as much as a celebration of its people. I've written about this ceremony in several different stories and contexts, but this year, given that today is April 18th is Saturday, I jumped at the chance to actually be here for it.
Market Street was almost entirely empty at 5 AM, save for the knot of people surrounding the Fountain. There were easily over a hundred of us, possibly as many as two hundred. I was definitely one of the youngest people there, aside from some little kids that accompanied their parents, but on the whole, it was a very diverse crowd. Some seemed to be treating the whole affair very solemnly, apparently focused on the death and destruction that beset the City. Others took more of a festival approach, with flags and whistles and the letters SF emblazoned on pretty much every article of clothing they were wearing. Others still seemed to be largely there in support of the fire department. There was a small but particularly visible contingent of people dressed in period costume, pulling the predawn gathering into the realm of living history now that the event itself is so close to passing from genuine living memory into purely written and photographic records or secondhand accounts. And, this being San Francisco, there were a few particularly colorful characters that seemed to have no connection to the ceremony itself, but were taking the chance for an audience at which to praise Obama, support peace, denounce Proposition 8, and generally garner smiles in reaction. Regardless of the undoubtedly disparate reasons for everyone's interest in attending, it was exciting to see that this many people still care enough about what happened to drag themselves out of bed in the pitch black and collectively remember.
The ceremony proper began with a local senator, the chief of the fire department, the event organizers, and various other fire officials and VIPs of some sort pulling up in an old (though I don't think 103-old) red fire engine. They were followed by a huge shiny black car containing two of the remaining survivors, ages 107 and 105. The survivors were, apparently, interviewed, but I don't think they had a microphone, and I unfortunately couldn't hear a word they said. I'd hoped that I could get a chance to talk to them, but that didn't end up happening. I would have asked, "How do you think the City's view and treatment of these events has changed over the past 103 years?" Judging by the fact that a couple of other survivors died in the past year, this is a question I - or anyone else - might not get another chance to ask.
All the talk stopped at 5:12 AM. There was supposed to be a minute of silence, and that was so important that a few people in the crowd actually shouted at the senator that it was 5:11 and he had to stop talking in a few seconds. And there was actual silence, though not for the full minute; much of it was filled with bagpipes. While I appreciate the use of the instrument in solemn occasions, I would have preferred the actual silence, a long minute of expected lack of obvious noise from anywhere in the streets of such a normally-busy city, a distinct contrast from the minute of rumbling and cracking and growling we were commemorating.
After the silence, there were a few brief words from the senator, the fire chief, author James D'Alessandro, and the event organizer. They spoke of how wonderful it was that so many of us had gathered, how great a City this is to survive so much and come out so strong, how being prepared for the repeat is key to continuing to live here. The actual description of the events went unsaid, however; it didn't need to be described, since we all knew what it was that brought us all out there.
And then we sang. Or some of us did -- I felt awkward in the fact that I did not know the words and thus could not participate. The song in question is called simply "San Francisco," and comes from the 1930s movie of the same name. I didn't know the melody either, but the nondeliberate polytonality of the crowd's singing was still obvious to me. It didn't bother me; the lack of being in a single key didn't matter at all. Those who were singing sounded like they meant it enough to make up for those of us who were keeping quiet, and that sentiment meant far more than the actual music did.
In the end, a wreath was laid on the Fountain, the VIPs returned to their respective vehicles, and they took off in a motorcade of blazing sirens, met with claps and cheers. They did a lap around the block and then disappeared down Market, leaving the crowd to disperse. Some did so immediately, but others lingered longer. I remained there until about 6:30, engaged in conversation about Enrico Caruso, spaghetti western operas, which buildings remain that show signs of damage, what kind of geological mechanisms are responsible and how we understand them so much better now, even though there's still so much we don't know.
The light was right at 6:12 AM. There was no daylight savings time 103 years ago, so their 5:12 was an hour ahead of ours. As I'd read in so many period descriptions of that day, the light was the slightly greeny blue of dawn, with a narrow strip of warm yellow silhouetting the Ferry Building. That was, in a sense, the lightest it got on April 18th 1906; the rest of the day was engulfed in flame and smoke enough to obscure all sense of time of day. April 18th 2009 has been gorgeous and cloudless.
Friday, April 17, 2009
Airliner Chronicles: LAX to SFO
I flew Virgin America from LAX to SFO today. I mention the airline specifically because I know for a fact that their particular air routes make for an awesome view out the window. (Also, their airplanes have wireless internet on them. Seriously. How cool is that?) But yes, if you are someone who likes landforms and faults and have to make this flight on that airline, I urge you to make the strongest effort possible to get a window seat on the right side of the plane. The view kept me far more entertained than the novelty of airborne WiFi ever could.
The first few minutes of the flight clung to the coast, but we swung back inland and caught up with the San Andreas Fault around the Big Bend. From there, we flew over...
The Carrizo Plain:
Cholame Valley (Parkfield's in there somewhere - just too small to see from that high up!):
Pinnacles National Monument (the exposed rock in the upper middle of the picture, with the city of Soledad in the foreground):
Loma Prieta (though I'm not entirely sure which of these peaks it is):
San Andreas in San Mateo (or possibly northern Santa Cruz) County (I think this is my favorite of the pictures):
I was definitely pretty giddy with excitement over the whole view by the time we landed at SFO. I suspect the way back to LAX will be just as awesome, if not more so, since I'll be flying in the middle of the day rather than at 6 PM. I managed to snag a window seat on the left side of the plane for that flight.
The first few minutes of the flight clung to the coast, but we swung back inland and caught up with the San Andreas Fault around the Big Bend. From there, we flew over...
The Carrizo Plain:
Cholame Valley (Parkfield's in there somewhere - just too small to see from that high up!):
Pinnacles National Monument (the exposed rock in the upper middle of the picture, with the city of Soledad in the foreground):
Loma Prieta (though I'm not entirely sure which of these peaks it is):
San Andreas in San Mateo (or possibly northern Santa Cruz) County (I think this is my favorite of the pictures):
I was definitely pretty giddy with excitement over the whole view by the time we landed at SFO. I suspect the way back to LAX will be just as awesome, if not more so, since I'll be flying in the middle of the day rather than at 6 PM. I managed to snag a window seat on the left side of the plane for that flight.
Monday, March 23, 2009
Geosong: Demolition Hammer's "Pyroclastic Annihilation"
In honor of last night's eruption of Mt. Redoubt - and its glorious timing with regards to someone called the governor of Louisiana's remark about volcanoes - I give you a death metal song about explosive volcanism.
Now, I'm not a death metal fan. It isn't even particularly on my listening radar, and tuneless screaming does not do much for me aesthetically. I do, however, think that if there is any situation in which this sort of musical treatment would be apt, the explosion of a mountain would be a good candidate. I also have to admit that I adore the title of this one. "Pyroclastic Annihilation," seriously, is a winner of a title.
My knowledge of the band that performs this song, Demolition Hammer, comes entirely from Wikipedia. They were a death/thrash metal band from the Bronx, active in the late 1980s and early 1990s. They disbanded around 1994 and are, from what I gather as an outsider to the genre, pretty obscure now.
The lyrics to "Pyroclastic Annihilation" have no sense of narrative or particular sentence structure of which to speak. It simply consists of various volcano-related terms and processes strung together in random order. The album this song comes from was produced in 1992, which was well before rampant Googling of things was prevalent, so I imagine the band must have trawled through some actual volcanology textbooks or articles to derive these lyrics. Most of the terms in there actually make sense, though there's a few that make me wonder what source they were actually looking at. Would anyone care to define "subrelluric forces" for me - a creative made-up definition definitely works, since I'm not finding anything real! Also, "intrusive tuff," guys? Yes, the random trawling for large and menacing phrases in a volcano book without any sense of meaning seems to have been the modus operandi here...
But still. A death metal song about explosive volcanism. For its flaws in lyrics, I still adore the concept. And it's actually screamed clearly enough that I can understand those lyrics without having to consult any external source. That's definitely worth something! And it also shows that even '90s death metal bands care about volcano monitoring.
Hear the song on YouTube (no video, though)
Lyrics
Oh crap, have I really not updated in almost a month? I had some really good excuses this month, at least, though they were stressful/depressing ones. It's spring break now. I have lots of things I actually want to write about, and will probably spew them out in the next few weeks.
Now, I'm not a death metal fan. It isn't even particularly on my listening radar, and tuneless screaming does not do much for me aesthetically. I do, however, think that if there is any situation in which this sort of musical treatment would be apt, the explosion of a mountain would be a good candidate. I also have to admit that I adore the title of this one. "Pyroclastic Annihilation," seriously, is a winner of a title.
My knowledge of the band that performs this song, Demolition Hammer, comes entirely from Wikipedia. They were a death/thrash metal band from the Bronx, active in the late 1980s and early 1990s. They disbanded around 1994 and are, from what I gather as an outsider to the genre, pretty obscure now.
The lyrics to "Pyroclastic Annihilation" have no sense of narrative or particular sentence structure of which to speak. It simply consists of various volcano-related terms and processes strung together in random order. The album this song comes from was produced in 1992, which was well before rampant Googling of things was prevalent, so I imagine the band must have trawled through some actual volcanology textbooks or articles to derive these lyrics. Most of the terms in there actually make sense, though there's a few that make me wonder what source they were actually looking at. Would anyone care to define "subrelluric forces" for me - a creative made-up definition definitely works, since I'm not finding anything real! Also, "intrusive tuff," guys? Yes, the random trawling for large and menacing phrases in a volcano book without any sense of meaning seems to have been the modus operandi here...
But still. A death metal song about explosive volcanism. For its flaws in lyrics, I still adore the concept. And it's actually screamed clearly enough that I can understand those lyrics without having to consult any external source. That's definitely worth something! And it also shows that even '90s death metal bands care about volcano monitoring.
Hear the song on YouTube (no video, though)
Lyrics
Oh crap, have I really not updated in almost a month? I had some really good excuses this month, at least, though they were stressful/depressing ones. It's spring break now. I have lots of things I actually want to write about, and will probably spew them out in the next few weeks.
Wednesday, February 25, 2009
...and then two more.
I was tempted, in light of specific sentences said by a particular politician yesterday, to forgo my planned Accretionary Wedge post and instead write about how every geologist, at some point in his or her life, should engage in a little volcano monitoring. I totally stand by my statement (and will be taking a class next quarter that absolutely involves volcano monitoring), but I also recall that we're collectively trying to come with 100 things, and there is certainly enough room in the budget of geological curiosity/exploration for me to write about those things in addition to snarking about things that other members of the geoblogosphere have already addressed so eloquently.
And now, the post I was planning to write before this madness went down.
The original 100 Places Meme lists the San Andreas Fault as a Must-See. I absolutely agree with this, but as I was marking the text on the list in bold, I got to thinking about how those three words mean a whole slew of very different places, spread out over hundreds of miles. The ultimate San Andreas experience is, of course, to drive the whole thing (or, well, the parts that are on land). I can't check off the full 800 miles yet, but I've been from the southern end of the Fault at the Salton Sea up through Point Reyes, mostly on roads that cling pretty close to the surface trace. I definitely recommend this drive as a means to check off the San Andreas on the original meme, but I also feel like there are several specific must-see sites along its trace (and within its system of associate faults) that deserve space on the expanded list.
The first place that came to mind, without me even having to really think about it, is Carrizo Plain National Monument, in rural San Luis Obispo County. The quintessential image of the San Andreas, the one that pops up in all sorts of textbooks and popular science books about earthquakes, the first photo that turns up when one does a google image search for the San Andreas, is from the Carrizo. It's an aerial photo of the Elkhorn Scarp, also known as the Dragon's Backbone, a 17-mile-long pressure ridge that, from above, looks like a gaping chasm into the depths of the Earth. (The original Superman movie actually does use the scarp as Supes' entry point into the fault...) It is a spectacular photo, but the view from the ground is equally breathtaking, and has the added bonus of debunking the faults-as-gaping-chasms myth.
The Carrizo Plain is one of the best places to see a wide variety of features associated with continental strike-slip faults. In addition to the outstanding pressure ridge, there is the famous Wallace Creek. This streambed crosses the San Andreas, but not without getting pulled around a bit first. Wallace Creek takes a sharp right angle turn as it meets the Fault, then parallels it for some 130 feet before heading back on its course. This shows the displacement power that the San Andreas has, and is all the more staggering when taking into account that some people think a good percentage of that displacement came from the 1857 earthquake alone. There are plenty of other offset streambeds that are less dramatic, as well as some channels that have been "beheaded" by the fault. The Carrizo also boasts more typical scarps, some spots of more trenchlike fault expression, stepovers with traceable surface expression, and a few (mostly dry) sag ponds.
If faults aren't really your thing, the Carrizo Plain is still worth a visit. The northernmost part of the Plain contains Soda Lake, a huge alkaline lake out of which many spectacular mineral samples (some of which are in the Visitor's Center, which is not open all the time) have been extracted from not very deep. The Carrizo is also thought to be an example of what the native Californian landscape might have looked like before the Europeans did anything to it - fields dominated by wildflowers and scrubby plants. For this reason, late March and early April are the best time to visit, since the wildflowers are out in full force, and the entire Plain is painted in shades of green, yellow, orange, and blue. (Don't go in the middle of the summer, though, unless you like triple digit temperatures.)
The next place I want to add to the list doesn't strictly feature the San Andreas; the town of Hollister's bisector is the Calaveras Fault, though the Calaveras branches off from the San Andreas just south of the town. The seat of San Benito County may lack scenes of breathtaking beauty that could make even a non-geologist drool, but it's also one of the best places to see the bizarre California-centric phenomenon known as aseismic creep. Creep is a phenomenon in which a fault moves slowly and steadily at around the tectonic loading rate, constantly releasing stress in a way that does not radiate seismic waves and generally prohibits enough buildup to cause a large quake (though some creeping faults may have asperities within the creeping zone that still accumulate stress and rupture seismically, even though creep continues around that zone). The main place (if not the only - I haven't heard of it elsewhere) this has been observed is in California, specifically on the Hayward, Calaveras, and Rogers Creek Faults in the Bay Area, the San Andreas between Parkfield and San Juan Bautista, and the Superstition Hills Fault near the Mexican border.
Creep can be measured with all sorts of complex instrumentation, but its easiest for the layperson to see when some sort of manmade structure gets put on the fault, and proceeds to get bent and deflected and cracked. The cities of Santa Rosa, Berkeley, Hayward, Fremont, and others all have the trademark offset curbs of a creeping fault, but I personally think that Hollister is the best city to look for offset because it looks like they've put less effort (or money) into patching up the distortion. Some sidewalks are bent several feet out of line, many streets are crossed by sets of en echelon cracks, and some houses and garages have obvious bulges in the walls and cracks in the foundation.
So Hollister is a good place to see creep as a phenomenon in and of itself, but it's also a clear exhibition of the interaction between the Earth itself and its inhabitants, of how people keep living in some places in spite of the geology. I suspect the fault was not known to be there when Hollister was first founded, which could explain some of the spectacularly bad locations of houses, but towns like this can be an example of how the hazards of the landscape should be taken into account when planning future development.
Not to mention that such intersections of humanity and seismicity make it clear that Fault Monitoring is also pretty darn important...
And now, the post I was planning to write before this madness went down.
The original 100 Places Meme lists the San Andreas Fault as a Must-See. I absolutely agree with this, but as I was marking the text on the list in bold, I got to thinking about how those three words mean a whole slew of very different places, spread out over hundreds of miles. The ultimate San Andreas experience is, of course, to drive the whole thing (or, well, the parts that are on land). I can't check off the full 800 miles yet, but I've been from the southern end of the Fault at the Salton Sea up through Point Reyes, mostly on roads that cling pretty close to the surface trace. I definitely recommend this drive as a means to check off the San Andreas on the original meme, but I also feel like there are several specific must-see sites along its trace (and within its system of associate faults) that deserve space on the expanded list.
The first place that came to mind, without me even having to really think about it, is Carrizo Plain National Monument, in rural San Luis Obispo County. The quintessential image of the San Andreas, the one that pops up in all sorts of textbooks and popular science books about earthquakes, the first photo that turns up when one does a google image search for the San Andreas, is from the Carrizo. It's an aerial photo of the Elkhorn Scarp, also known as the Dragon's Backbone, a 17-mile-long pressure ridge that, from above, looks like a gaping chasm into the depths of the Earth. (The original Superman movie actually does use the scarp as Supes' entry point into the fault...) It is a spectacular photo, but the view from the ground is equally breathtaking, and has the added bonus of debunking the faults-as-gaping-chasms myth.
The Carrizo Plain is one of the best places to see a wide variety of features associated with continental strike-slip faults. In addition to the outstanding pressure ridge, there is the famous Wallace Creek. This streambed crosses the San Andreas, but not without getting pulled around a bit first. Wallace Creek takes a sharp right angle turn as it meets the Fault, then parallels it for some 130 feet before heading back on its course. This shows the displacement power that the San Andreas has, and is all the more staggering when taking into account that some people think a good percentage of that displacement came from the 1857 earthquake alone. There are plenty of other offset streambeds that are less dramatic, as well as some channels that have been "beheaded" by the fault. The Carrizo also boasts more typical scarps, some spots of more trenchlike fault expression, stepovers with traceable surface expression, and a few (mostly dry) sag ponds.
If faults aren't really your thing, the Carrizo Plain is still worth a visit. The northernmost part of the Plain contains Soda Lake, a huge alkaline lake out of which many spectacular mineral samples (some of which are in the Visitor's Center, which is not open all the time) have been extracted from not very deep. The Carrizo is also thought to be an example of what the native Californian landscape might have looked like before the Europeans did anything to it - fields dominated by wildflowers and scrubby plants. For this reason, late March and early April are the best time to visit, since the wildflowers are out in full force, and the entire Plain is painted in shades of green, yellow, orange, and blue. (Don't go in the middle of the summer, though, unless you like triple digit temperatures.)
The next place I want to add to the list doesn't strictly feature the San Andreas; the town of Hollister's bisector is the Calaveras Fault, though the Calaveras branches off from the San Andreas just south of the town. The seat of San Benito County may lack scenes of breathtaking beauty that could make even a non-geologist drool, but it's also one of the best places to see the bizarre California-centric phenomenon known as aseismic creep. Creep is a phenomenon in which a fault moves slowly and steadily at around the tectonic loading rate, constantly releasing stress in a way that does not radiate seismic waves and generally prohibits enough buildup to cause a large quake (though some creeping faults may have asperities within the creeping zone that still accumulate stress and rupture seismically, even though creep continues around that zone). The main place (if not the only - I haven't heard of it elsewhere) this has been observed is in California, specifically on the Hayward, Calaveras, and Rogers Creek Faults in the Bay Area, the San Andreas between Parkfield and San Juan Bautista, and the Superstition Hills Fault near the Mexican border.
Creep can be measured with all sorts of complex instrumentation, but its easiest for the layperson to see when some sort of manmade structure gets put on the fault, and proceeds to get bent and deflected and cracked. The cities of Santa Rosa, Berkeley, Hayward, Fremont, and others all have the trademark offset curbs of a creeping fault, but I personally think that Hollister is the best city to look for offset because it looks like they've put less effort (or money) into patching up the distortion. Some sidewalks are bent several feet out of line, many streets are crossed by sets of en echelon cracks, and some houses and garages have obvious bulges in the walls and cracks in the foundation.
So Hollister is a good place to see creep as a phenomenon in and of itself, but it's also a clear exhibition of the interaction between the Earth itself and its inhabitants, of how people keep living in some places in spite of the geology. I suspect the fault was not known to be there when Hollister was first founded, which could explain some of the spectacularly bad locations of houses, but towns like this can be an example of how the hazards of the landscape should be taken into account when planning future development.
Not to mention that such intersections of humanity and seismicity make it clear that Fault Monitoring is also pretty darn important...
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