I don’t see what all the hoop-la is about. None of us can prove what caused the derailment. I just analyze the circumstantial evidence and apply my own knowledge of the subject, much of which comes from practical experience. I am not just creatively producing theories out of nothing and attempting to validate them by internet links.
Basically, I am just curious about causes of mechanical failures because I have an interest in the topic, plus enough experience to identify the questions. And because I get frustrated at having to wait for some official announcement of the cause that may never come, I just speculate and offer my conclusions. Nobody is under any obligation to accept my opinion. It does not interfere with the official investigation. So what’s the big deal?
It seems like some people here refuse to speculate and feel that others don’t have the right to speculate. They cannot stop someone from speculating, so they insist that the person speculating has got to have flaws in their speculating theory. They try to debunk an opinion. At this point, credentials mean nothing to those who insist that speculation must be banned. There are no credentials that they will accept that would validate the speculative content because they can’t stand speculation.
I have been accused here of trying to cover all bases by sufficiently broadening my speculation, with the motive of saying, “See, I told you so,” no matter what the cause turns out to have been. But that is not the case. My speculation is only on one cause. That is train-triggered liquefaction of the saturated roadbed, which caused the soil to suddenly lose its ability to support the train. I am leaving out all other possible causes such as erosion, flood water sweeping the train off the track, slope failure, landslides of asteroids, or any non-flood-related cause.
I have a few reasons for ruling out all non-flood-related causes. One of those reasons is the disaster declaration by the State of Iowa, which says the derailment was caused by the flood.
Murphy Siding charlie hebdo We know what Volker's limitations, expertise and credentials are to speak about the soil problems. We know that Euclid is not a soil engineer, but he cites from the relevant sources that we can examine and learn from. We know that neither Murphy nor myself have relevant creds nor do we pretend to. What are Husman's chops? If that requirement is not asked of euclid, why would it be required of anyone else?
charlie hebdo We know what Volker's limitations, expertise and credentials are to speak about the soil problems. We know that Euclid is not a soil engineer, but he cites from the relevant sources that we can examine and learn from. We know that neither Murphy nor myself have relevant creds nor do we pretend to. What are Husman's chops?
We know what Volker's limitations, expertise and credentials are to speak about the soil problems. We know that Euclid is not a soil engineer, but he cites from the relevant sources that we can examine and learn from. We know that neither Murphy nor myself have relevant creds nor do we pretend to. What are Husman's chops?
If that requirement is not asked of euclid, why would it be required of anyone else?
For the simple reason he doesn't claim special knowledge, just the ability to do searches relevant to the topic. He makes citations. Many others do not. Some on here do not like links.
Thanks to Chris / CopCarSS for my avatar.
BNSF not in favor of former DOT 111 tank cars updated to DOT 117 specs.
https://www.railwayage.com/freight/bnsf-to-limit-retrofit-tank-cars-report/
Never too old to have a happy childhood!
dehusmanVolker: Metaphors for what we are talking about. You have a beam that centilevers from a wall. You drop a load on it and the beam shears off and the load falls to the ground. That's a slope failure. You have a beam that centilevers from a wall. You drop a load on it and the beam deforms and bends, the load falls to the ground. That's liquifaction.
First, no need to explain the difference between liquifaction and landslide to me. As I said before I'm a civil engineer and that means I learned at least the fundamentals in soil mechanics and geotechnic before specializing in structural design, where these fundamentals are needed too.
When you make comparisons you should do it right. A cantilever beam usualy has a stress failure caused by the bending moment not a shear failure. Brackets experience shear failure.
dehusmanOne is a shear failure, the other is a deformation.
Wrong, both are shear failures only with different consequences.
From Euclid's link: A generally comparable definition was published by the American Society of Civil Engineers ( 1958, p. 1826-22) and quoted by the American Geological Institute (1972, p. 410) as follows: "The sudden large decrease of shearing resistance of a cohesionless soil, caused by a collapse of the structure by shock or strain, and associated with a sudden but temporary increase of the pore fluid pressure [is liquefaction]. It involves a temporary transformation of the material into a fluid mass."
As there are a number of reasons for liquifaction, there are a number of causes for a landslide. One of these possible causes is liquifaction.Regards, Volker
Murphy Siding VOLKER LANDWEHR Murphy Siding I was asking if euclid could show where a train had derailed because of liquefaction. He's now off to the races again trying to re-interpret the words of others to mean what he wants them to mean. I don’t know what caused the derailment. euclid does not know either. Now you are starting to explain what you meant. Your post I replied to sounds different to me. You blame him that he now says it was liquifaction. My answer was, he stated that already on June 23, 2018. Regarding an example for liquification causing a train derailment he answered that he already provided a link and would look for it again. We all don't know what happened and Euclid admitted it several times. The main difference between you and him is, he has an opinion and offers it. From all I have watched here you are one of the first to pick on him even if he is right. It doesn't seem to interest you.Regards, Volker No, no, no. He has said from the start he thought it was liquefaction. He is now retroactively making derailments caused by landslides in foreign countries into cases of liquefaction causing derailments. I don't believe that's correct to suggest that I "pick on him even when he's right". It's fair to say I challenge him when he thinks he's right, just because he says he's right. There's a difference-the mere fact that he says something doesn't automatically mean what he says is right. Tree hit on this same concept earlier. Apparantly it's important that I offer an opinion of what caused the derailment, even though none of us knows. I'd say that the train was hit by an asteroid. Some trains derailed in foreign countries due to landslides. If I carry this discussion far enough I could suggest that the landslides were caused by asteroids as well.
VOLKER LANDWEHR Murphy Siding I was asking if euclid could show where a train had derailed because of liquefaction. He's now off to the races again trying to re-interpret the words of others to mean what he wants them to mean. I don’t know what caused the derailment. euclid does not know either. Now you are starting to explain what you meant. Your post I replied to sounds different to me. You blame him that he now says it was liquifaction. My answer was, he stated that already on June 23, 2018. Regarding an example for liquification causing a train derailment he answered that he already provided a link and would look for it again. We all don't know what happened and Euclid admitted it several times. The main difference between you and him is, he has an opinion and offers it. From all I have watched here you are one of the first to pick on him even if he is right. It doesn't seem to interest you.Regards, Volker
Murphy Siding I was asking if euclid could show where a train had derailed because of liquefaction. He's now off to the races again trying to re-interpret the words of others to mean what he wants them to mean. I don’t know what caused the derailment. euclid does not know either.
Now you are starting to explain what you meant. Your post I replied to sounds different to me.
You blame him that he now says it was liquifaction. My answer was, he stated that already on June 23, 2018. Regarding an example for liquification causing a train derailment he answered that he already provided a link and would look for it again.
We all don't know what happened and Euclid admitted it several times. The main difference between you and him is, he has an opinion and offers it.
From all I have watched here you are one of the first to pick on him even if he is right. It doesn't seem to interest you.Regards, Volker
No, no, no. He has said from the start he thought it was liquefaction. He is now retroactively making derailments caused by landslides in foreign countries into cases of liquefaction causing derailments. I don't believe that's correct to suggest that I "pick on him even when he's right". It's fair to say I challenge him when he thinks he's right, just because he says he's right. There's a difference-the mere fact that he says something doesn't automatically mean what he says is right. Tree hit on this same concept earlier. Apparantly it's important that I offer an opinion of what caused the derailment, even though none of us knows. I'd say that the train was hit by an asteroid. Some trains derailed in foreign countries due to landslides. If I carry this discussion far enough I could suggest that the landslides were caused by asteroids as well.
You sound hysterical.
Oh, oh a new track to wander off on. NOT ..
I have been to Alaska and walked on and seen soils that liquify. I have seen soils become unstable from excessive rainfall permiating the soil and causing it to loose it's ability to support a load. I have some doubt that liquification occurred in Doon. While a washout of part of the embankment is a possibility, I don't believe there was sufficient current to cause that. From what I saw in the video, the embankment appeared to be intact. I suspect that this is more likely to be a mechanical failure such as a broken axle or similar event coincidental to the flood.
I hope we get info soon to allow the forum to relax and find some other good subject to squabble about.
Volker: Metaphors for what we are talking about.
You have a beam that centilevers from a wall. You drop a load on it and the beam shears off and the load falls to the ground. That's a slope failure.
You have a beam that centilevers from a wall. You drop a load on it and the beam deforms and bends, the load falls to the ground. That's liquifaction.
One is a shear failure, the other is a deformation.
Either way the load hits the ground. But the mechanism of failure is not the same, shear is not the same as bending deformation.
Dave H. Painted side goes up. My website : wnbranch.com
EuclidI would say that gravity is an essential part of the cause in every landslide. But there are two parts to the cause of a landslide. One is gravity that pulls the soil downward and the other is the factor that causes the soil to let go so to speak. Gravity is there all the time, so a standing hillside does not just to decide on its own one day to lose its grip and go with gravity. Something has to weaken its grip or its ability to withstand the pull of gravity. Liquefaction can do that.
EuclidI replied that such a landslide may have been actually caused by liquefaction because Dave made a point of presenting that landslides and liquefaction are two different mechanisms.
I NEVER mentioned landslides. You are the one that keeps renaming things with other names in order to confuse things. I ONLY discussed that slope failure is another possible cause, since it is the most common cause and that slope failure and liquifaction are two different things.
You are so fixated on liquifaction I wanted to point out that there are lots of other causes for subgrade failure.
It is also possible that there are multiple causes for the failure (landslides are problably only a .000000000000000000000000000001% chance, its Iowa not Colorado). There may be contributory causes. Its also possible that they may never know the detailed cause of the derailment. Between the water, the derailment plowing things up, the rerailing efforts, the mitigation and the restoration, the ground might be so chewed up that they can't identify exactly what happened, other than it was a subgrade failure (if that is even the cause, since nobody has said, a broken rail or wheel, bad crosslevel of any number of things is equally as likely an option.)
VOLKER LANDWEHRI already posted it elsewhere and think it is still correct: It doesn't seem easy for some railroaders to accept different opinions and questioning.
That would be because the railroaders have a rulebook in their grip by which they must live.
Opinions are not a part of operating a railroad. The rules are. Questions will generally be addressed by going to the rulebook. Sometimes that doesn't square with what people want to hear.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Murphy SidingMy theory is that gravity is the biggest factor in landslides.
I would say that gravity is an essential part of the cause in every landslide. But there are two parts to the cause of a landslide. One is gravity that pulls the soil downward and the other is the factor that causes the soil to let go so to speak. Gravity is there all the time, so a standing hillside does not just to decide on its own one day to lose its grip and go with gravity. Something has to weaken its grip or its ability to withstand the pull of gravity. Liquefaction can do that.
Liquefaction causes soil to lose its solid or cohesive structure and turn into a liquid mass. And it can do this to soil no matter whether the soil is on a hillside or soil lying flat in a field. If it happens to soil on a hillside, the suddenly liquefied soil mass will slide or flow down with the pull of gravity. It if happens to soil lying flat in a field, gravity will have no effect, and the soil won't move. However, it will have lost its ability to support a load, so if a building is standing on it, the building may sink or tip over.
So, if sloped soils develop liquefaction, they can definitely become a landslide or slope failure.
If the soil of a railroad fill develops liquefaction, it will lose its ability to support the train. The banks sides may also lose their ability to support themselves. So there may be some slope failure. But even if there was at Doon, I believe the primary cause was liquefaction distributed across the entire fill, and most developed directly under the train where the vibration and weight would have the greatest effect. Look at it this way: If liquefaction was developed sufficiently to cause the banks to slide down, it was surely sufficient to cause the roadbed to completely lose its ability to support the train.
Murphy SidingI was asking if euclid could show where a train had derailed because of liquefaction. He's now off to the races again trying to re-interpret the words of others to mean what he wants them to mean. I don’t know what caused the derailment. euclid does not know either.
VOLKER LANDWEHR Murphy Siding Back up. Reread what you wrote. You are saying that based on the information about landslides causing derailments that you have now determined that it was liquifaction. Euclid post of June 23, 2018 in "the BNSF derailment at Doon, Iowa" thread: It is much more likely that the high water saturated the fill, and then the vibratory action of the passing train increased the saturation to the point where roadbed lost its ability to support the train. That is a description of liquifaction. Murphy Siding Being probably the only one on the forum that has been to Doon, Iowa I can confidently tell you that landslides had nothing to do with this derailment. So what was the cause? Liquifaction doesn't necessarily lead to landslides. Think of trying to walk on water. Suddenly there is no footing. It hasn't to happen inside the fill it could happen in the subsoil.Regards, Volker
Murphy Siding Back up. Reread what you wrote. You are saying that based on the information about landslides causing derailments that you have now determined that it was liquifaction.
Euclid post of June 23, 2018 in "the BNSF derailment at Doon, Iowa" thread: It is much more likely that the high water saturated the fill, and then the vibratory action of the passing train increased the saturation to the point where roadbed lost its ability to support the train.
That is a description of liquifaction.
Murphy Siding Being probably the only one on the forum that has been to Doon, Iowa I can confidently tell you that landslides had nothing to do with this derailment.
So what was the cause?
Liquifaction doesn't necessarily lead to landslides. Think of trying to walk on water. Suddenly there is no footing. It hasn't to happen inside the fill it could happen in the subsoil.Regards, Volker
I was asking if euclid could show where a train had derailed because of liquefaction. He's now off to the races again trying to re-interpret the words of others to mean what he wants them to mean. I don’t know what caused the derailment. euclid does not know either.
Euclid Murphy Siding Haveyou seen reference to it ever causing a derailment before? I posted a link to derailments caused by liquefaction earlier in this thread. As I recall, these derailment examples were not in the U.S. I will see if I can find that link, and post it again. In any case, I believe that liquefaction may have been the underlying cause of landslides along railroads, which derailed trains. As that recent link suggests, these landslides may have been referred to as such without any deeper determination involving liquefaction as the underlying cause. As I mentioned, it is the shaking of the ground that often triggers the soil change that is liquefaction. Any vehicle can shake the ground, but freight trains are ideal because the shaking from them is strong, prolonged, and finely pulsed. So I would conclude that ground shaking caused by trains is second only to earthquakes as a cause of ground shaking.
Murphy Siding Haveyou seen reference to it ever causing a derailment before?
I posted a link to derailments caused by liquefaction earlier in this thread. As I recall, these derailment examples were not in the U.S. I will see if I can find that link, and post it again. In any case, I believe that liquefaction may have been the underlying cause of landslides along railroads, which derailed trains. As that recent link suggests, these landslides may have been referred to as such without any deeper determination involving liquefaction as the underlying cause.
As I mentioned, it is the shaking of the ground that often triggers the soil change that is liquefaction. Any vehicle can shake the ground, but freight trains are ideal because the shaking from them is strong, prolonged, and finely pulsed. So I would conclude that ground shaking caused by trains is second only to earthquakes as a cause of ground shaking.
Murphy Siding Euclid Murphy Siding Haveyou seen reference to it ever causing a derailment before? I posted a link to derailments caused by liquefaction earlier in this thread. As I recall, these derailment examples were not in the U.S. I will see if I can find that link, and post it again. In any case, I believe that liquefaction may have been the underlying cause of landslides along railroads, which derailed trains. As that recent link suggests, these landslides may have been referred to as such without any deeper determination involving liquefaction as the underlying cause. As I mentioned, it is the shaking of the ground that often triggers the soil change that is liquefaction. Any vehicle can shake the ground, but freight trains are ideal because the shaking from them is strong, prolonged, and finely pulsed. So I would conclude that ground shaking caused by trains is second only to earthquakes as a cause of ground shaking. Back up. Reread what you wrote. You are saying that based on the information about landslides causing derailments that you have now determined that it was liquifaction. Being probably the only one on the forum that has been to Doon, Iowa I can confidently tell you that landslides had nothing to do with this derailment.
Back up. Reread what you wrote. You are saying that based on the information about landslides causing derailments that you have now determined that it was liquifaction. Being probably the only one on the forum that has been to Doon, Iowa I can confidently tell you that landslides had nothing to do with this derailment.
Dave H. is the only one who speculates that the Doon derailment was caused by slope failure, which I have also referred to as a landslide. If there was a slope failure at Doon, I assume he means the sloping side of the submerged fill slid down and caused a loss of support for the track.
I replied that such a landslide may have been actually caused by liquefaction because Dave made a point of presenting that landslides and liquefaction are two different mechanisms. I am not so sure of that claim. In any case, liquefaction can cause landslides, but it can also just cause standing soil to become liquid and lose its ability to carry loads such as buildings or trains. So I have no opinion about slope failure at Doon. I think the cause was liquefaction, and most likely that the liquifaction merely caused the standing soil to lose its ability to support the train.
There may have been some slope failure ad Doon, but even if their was, it was caused by the liquefaction. So I see potential slope failure at Doon to be merely a symptom of the underlying liquefaction, as opposed to an alternate cause altogether.
What exactly are you referring to when you say, "Back up. Reread what you wrote." ?
Murphy SidingBack up. Reread what you wrote. You are saying that based on the information about landslides causing derailments that you have now determined that it was liquifaction.
Murphy SidingBeing probably the only one on the forum that has been to Doon, Iowa I can confidently tell you that landslides had nothing to do with this derailment.
tree68Because I hate to see incorrect information left to stand unchallenged.
Not all of his answers are wrong, but they are mostly handled as such.
tree68In case you're wondering what all this "yes, but..." stuff is about - if someone disproves one of Bucky's theories, his strategy has always been to backpedal and approach from a different direction. "Yes, but..."
I'm reading this forum since about ten years. So I already learned about it. On the other hand I learned how what you call "bullies" (not my words) try to drive such threads into insanity to get it locked. A few railroaders got banned for doing this.
tree68Instead of defending Bucky from all of the "bullies," try using the same level of incredulity toward his posts that others use. It will soon become apparent to you...
I'm only definding Euclid when I think he is right or he asks the right questions.I'll question him if necessary but perhaps in different way.
I already posted it elsewhere and think it is still correct: It doesn't seem easy for some railroaders to accept different opinions and questioning.
Yes, I learn a lot from railroaders here. Are they unerring? For sure not. And I think it is sometimes necessary to get questioned from an outsider to loose ones blinkers. And a real expert allows to be questioned and doesn't hide behind being an expert.Regards, Volker
EuclidYou advise others to use the same level of incredulity that you and others use when reading my comments. Maybe you and your “others” should tone down your level of incredulity and consider what I actually say rather than just make fit your preconceived template. All debate involves the changing of terms to help clarify one’s position and make it more convincing. That is not backpedaling.
Healthy skepticism is desirable when it is questioning in the marketplace of ideas. But when it becomes little more than a series of snide, ad hominem attacks dressed up as "objective posts" and merely because of the name of the poster, that is simply garbage.
Euclid tree68 charlie hebdo And the rest of us can read and learn something, maybe. You may see it as providing more information - some see it as an attempt to cover all of the bases so if a cause is made public Bucky can say "see, I told you so!" Often times hearing “See, I told you so!” is in the mind of the beholder. Maybe you should work on that a little. Just a thought from a non-soil engineer.
tree68 charlie hebdo And the rest of us can read and learn something, maybe. You may see it as providing more information - some see it as an attempt to cover all of the bases so if a cause is made public Bucky can say "see, I told you so!"
charlie hebdo And the rest of us can read and learn something, maybe.
You may see it as providing more information - some see it as an attempt to cover all of the bases so if a cause is made public Bucky can say "see, I told you so!"
On soil liquefaction, he posted a fatual link to USGS soil engineers. And what's wrong with "covering all the bases" i.e. examining multiple hypotheses? It is what practicing engineers, such as Volker tend to do. So do people who use scientific methodologies.
tree68 VOLKER LANDWEHR If you want to end it, why not stop answering? Because I hate to see incorrect information left to stand unchallenged. In case you're wondering what all this "yes, but..." stuff is about - if someone disproves one of Bucky's theories, his strategy has always been to backpedal and approach from a different direction. "Yes, but..." Or "I was merely giving my opinion." Instead of defending Bucky from all of the "bullies," try using the same level of incredulity toward his posts that others use. It will soon become apparent to you...
VOLKER LANDWEHR If you want to end it, why not stop answering?
Because I hate to see incorrect information left to stand unchallenged.
In case you're wondering what all this "yes, but..." stuff is about - if someone disproves one of Bucky's theories, his strategy has always been to backpedal and approach from a different direction. "Yes, but..."
Or "I was merely giving my opinion."
Instead of defending Bucky from all of the "bullies," try using the same level of incredulity toward his posts that others use. It will soon become apparent to you...
Do you always know whether information is correct or not? “Yes but,” is nothing more than my graciousness in not crassly rejecting everything you said. I regard that sort of total rejection as being an act of open hostility, as we sometimes see in forum discussion.
I do not believe that you are entirely wrong all the time. In your perpetual quest to shoot down incorrect information, I get the impression that you feel that anything I say is incorrect information.
As you know, the term “backpedal” has a negative connotation. You assign that term to me as a characteristic based on my restating the terms of my argument. I think that if you are honest, you will admit that what really bothers you is that I make strong arguments and don’t back down when you come along correcting my information.
You advise others to use the same level of incredulity that you and others use when reading my comments. Maybe you and your “others” should tone down your level of incredulity and consider what I actually say rather than just make fit your preconceived template. All debate involves the changing of terms to help clarify one’s position and make it more convincing. That is not backpedaling.
Well said, Larry.
It is truly sad that one poster continnually posits new explanations of another person's actions when the full story has not presented to the public--or asks questions that cannot be answered with the currently available knowledge. Several incidents back the simile of beating a dead horse was presented--and the beating conitnued.
Johnny
Murphy SidingHaveyou seen reference to it ever causing a derailment before?
VOLKER LANDWEHRIf you want to end it, why not stop answering?
Euclid Murphy Siding Are you a soil engineer? I don't believe that I have made any claims that require me to be a soil engineer (which I am not). I'm just touching the basics here, and you don't need to be a soil engineer to understand my points. I thought the quote from the link raised an interesting and pertinent point about the confusion over liquefaction and its consequences. That is why I directed it to Dave. I tried to put it into non-soil engineering terms for all the non-soil engineers out there. Are you a soil engineer? As I recall, the PDF makes a distinction in which liquefaction is not ground movement even though it is often cited in cases of severe ground movement such as in earthquakes. What liquefaction does is make ground movement possible. I believe that this is the basic point of the quote citing some confusion about liquefaction and its consequenses. By the way, are you a soil engineer? Do you know a lot of soil engineers?
Murphy Siding Are you a soil engineer?
I don't believe that I have made any claims that require me to be a soil engineer (which I am not). I'm just touching the basics here, and you don't need to be a soil engineer to understand my points. I thought the quote from the link raised an interesting and pertinent point about the confusion over liquefaction and its consequences. That is why I directed it to Dave. I tried to put it into non-soil engineering terms for all the non-soil engineers out there. Are you a soil engineer?
As I recall, the PDF makes a distinction in which liquefaction is not ground movement even though it is often cited in cases of severe ground movement such as in earthquakes. What liquefaction does is make ground movement possible. I believe that this is the basic point of the quote citing some confusion about liquefaction and its consequenses. By the way, are you a soil engineer? Do you know a lot of soil engineers?
charlie hebdo Murphy Siding Euclid: Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.” Are you a soil engineer? Are you? He's not a soild engineer, but his quote is from people at the USGS who are. And the rest of us can read and learn something, maybe.
Murphy Siding Euclid: Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.” Are you a soil engineer?
Euclid: Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.” Are you a soil engineer?
Are you? He's not a soild engineer, but his quote is from people at the USGS who are. And the rest of us can read and learn something, maybe.
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