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Earth Science

New Mexico Is Stretching, GPS Reveals 117

Posted by Soulskill
from the too-many-tacos dept.
Velcroman1 writes "New Mexico's borders are gradually gaining girth, according to the Albuquerque Journal. It's not much, and it's not happening very fast — the state is getting about an inch wider every 40 years — but the state is unquestionably expanding, according to University of Colorado geophysicist Henry Berglund and his colleagues. Using a collection of 25 extra-precise GPS receivers planted across New Mexico and Colorado, Berglund determined that the cities of Albuquerque and Santa Fe are creeping away from each other. The rate of change seems ever so slow to the untrained ear, described as approximately 1.2 'nanostrains' per year."
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New Mexico Is Stretching, GPS Reveals

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  • Black Mesa (Score:5, Funny)

    by bonch (38532) * on Tuesday January 17, 2012 @08:46PM (#38733376)

    But the effect in continental interiors -- on states not near the edge of those plates -- was a new one, the scientists said. Whether an upwelling in the gooey mantle that lies beneath the crust or a sag in the plates themselves, what exactly drives the growth remains a mystery.

    Probably those experiments over at Black Mesa. By the way, the portrayal of New Mexico in Half-Life always amused me, with the cartoonish Looney Tunes cliffs and plateaus. With the exception of the northern area of the state, it's mostly just weeds as far as the eye can see [imgur.com], littered with the occasional beer can. We have good Mexican food, though.

    • by Nidi62 (1525137)
      Well, with a name like Black Mesa, it wouldn't make sense to have a flat plain as far as the eye can see. Gotta keep the game believable, you know.
      • by bonch (38532) *

        There actually is a Black Mesa, New Mexico [imgur.com], though I don't know if the in-game location has any relation (I imagine there are probably several Black Mesas in the deserts of America.

        • by Megahard (1053072)
          A topo map search finds 20 places in Arizona named Black Mesa.
          • by RockDoctor (15477)
            Such a cunning plan by the spooks to hide their nefarious activities. So much more sensible than calling it something like "Area 52."
    • Re:Black Mesa (Score:4, Insightful)

      by PRMan (959735) on Tuesday January 17, 2012 @09:31PM (#38733736)
      Actually, I recently drove through New Mexico and was surprised by the green fields, grazing animals and tons of nice-looking farms/ranches along a long stretch of road. It was not what Looney Tunes said it would be (that was Arizona).
      • by ThorGod (456163)

        Actually, I recently drove through New Mexico and was surprised by the green fields, grazing animals and tons of nice-looking farms/ranches along a long stretch of road. It was not what Looney Tunes said it would be (that was Arizona).

        Actually, there's a good amount of agriculture in NM, at least as far south as San Antonio, NM. Since I've moved away, that's one of the top things I miss. Az and Nv both have places they live up to the baren stereotype better.

      • by rts008 (812749) on Wednesday January 18, 2012 @06:43AM (#38736412) Journal

        You took a wrong turn in Albuquerque....

    • by jbeaupre (752124)

      You must be in the eastern part. I've live in 5 counties, all of them had mesas, mountains, forests, and badlands of one sort or another. Multiple mountain ranges: Gila, Black, Organ, Manzano, Sandia, Sangre di Cristo, Flores, Mt. Taylor, etc. The only thing close to that picture west of the Pecos is between Las Cruces and Deming (but that area doesn't even have the weeds).

      There's a reason so many Sci Fi movies are shot in NM these days: Most of the state looks unusual. It's funny watching Breaking Bad

      • A bit further between Deming and Silver City, there are farms, cows and even a herd of antelope near Bayard. No word on whether they were playing or not. Stay tuned. Towards Lordsburg.... not so much. Of anything.

        • by Endo13 (1000782)

          Damn, seeing these posts about that part of the state makes me miss it. Lived in Mimbres Valley 20 years ago when I was a kid. Silver City was where we did our shopping.

    • by mjwx (966435)

      Probably those experiments over at Black Mesa. By the way, the portrayal of New Mexico in Half-Life always amused me, with the cartoonish Looney Tunes cliffs and plateaus. With the exception of the northern area of the state, it's mostly just weeds as far as the eye can see [imgur.com], littered with the occasional beer can. We have good Mexican food, though.

      Well, if you were building a secret lab to run probably illegal experiments into inter-dimensional travel with the potential to bring vicious invaders to earth, which part of New Mexico would you pick.

    • One man's weeds, another man's area of natural beauty..... [nature.org].

    • The portrayal of New Mexico with the cartoonish Looney Tunes cliffs and plateaus.

      Let's not forget George Herriman's seminal comic strip Krazy Kat, source of my sig.
      Kokonino Kounty's mesas and surrealistic landscapes predate The Road Runner by more than a quarter century.

      Finally, I can't resist taking a jab at that headline:
      New Mexico Is Yawning, Sonar Reveals.

    • Good job, idiot. You linked to a page with words on it. You should try the preview button some time, make sure your links actually work before posting.

      -Average Joe

  • by rbowen (112459) Works for SourceForge on Tuesday January 17, 2012 @08:55PM (#38733426) Homepage

    So much for driving to California next summer. It'll be farther away by then.

    • Re:There go my plans (Score:5, Interesting)

      by R3d M3rcury (871886) on Tuesday January 17, 2012 @09:56PM (#38733926) Journal

      Perhaps I'm taking this too literally...

      I'm not sure New Mexico can get any wider--it's borders are set along latitude and longitude lines. So it's more likely that Albuquerque will eventually end up in Arizona and Santa Fe will end up in Texas.

      • Re:There go my plans (Score:4, Informative)

        by Anonymous Coward on Tuesday January 17, 2012 @11:24PM (#38734420)

        I'm not sure New Mexico can get any wider--it's borders are set along latitude and longitude lines.

        It's borders are not defined by the latitude and longitude lines, but by the markers set by the surveying team which attempted to follow the latitudes and longitudes. In pretty much every country, certainly all regions of North America, boundaries that were intended to follow specific latitudes or longitudes don't change as our ability to more accurately define these imaginary lines on the globe. Typically the act in Canada or the U.S. that defines the national, state/province or county borders as following specific lat. or long. lines also includes the phrase "as defined by" and the specific survey mission that defined the border using the technology then available.

        So every border that is popularly defined by a latitude or longitude is rarely accurate as the technology was often quite crude compared to what we can do today.
        Therefore, yes New Mexico can and is getting wider and Albuquerque and Santa Fe are going to remain part of N.M. as long as some kind of hispanic revolution doesn't occur. ;-)

        • by c++0xFF (1758032)

          I presume similar provisions have been made for boundaries defined by rivers? At first, a river seems to be a natural border ... this side is ours, that side is yours. But rivers have a tendency to change over time, sometimes very dramatically.

        • by Obfuscant (592200)

          It's borders are not defined by the latitude and longitude lines, but by the markers set by the surveying team which attempted to follow the latitudes and longitudes.

          Further, the actual lat and lon lines depend on which datum one uses for the measurement. WGS84 and NAD27 are different. Not by much, but enough.

      • I'm not sure New Mexico can get any wider--it's borders are set along latitude and longitude lines. So it's more likely that Albuquerque will eventually end up in Arizona and Santa Fe will end up in Texas.

        Unless New Mexico was gaining altitude. As the r to the earths center grew, so would the distance between the two state lines while staying at the same latitude and longitude lines.

  • by Anonymous Coward on Tuesday January 17, 2012 @08:58PM (#38733454)

    ...is so bad in the United States now, even the GROUND is getting fatter.

  • New Mexico was where LightSquared was testing their LTE system...
  • I believe the same thing is happening to Nevada. It's what causes the "horst and graben" faulting and the north-south mountain chains.

  • Not News (Score:5, Funny)

    by sunderland56 (621843) on Tuesday January 17, 2012 @08:59PM (#38733480)
    Yeah, yeah, we know - America is getting fatter.
    • And then there is the expansion of the universe to consider. Whats's the red shift of Mexico City right now?

      • The leading political party is liberal, so I'd say it's more of a blue shift. This very handily brings us back to the Half Life comments at the top.

        Apparently a side effect of resonance cascades is pre-destination and determinism.
    • Yeah, but it's not that bad--1 inch every 40 years. Personally, I added about an inch in the past year.

      • by rts008 (812749)

        Personally, I added about an inch in the past year.

        Piker!
        I can claim 3cm's this year, n00b!

        *The above was to be taken in jest.*

  • They have to put the spoil from all those tunnels someplace!
  • Wait, are we caring?

  • GPS Accuracy (Score:4, Interesting)

    by Proudrooster (580120) on Tuesday January 17, 2012 @09:18PM (#38733628) Homepage
    Fellow Slashdotters... this is a little off topic, but is there any way to get accuracy out of GPS? I can barely get plus/minus 12 feet of accuracy out of my GPS in the best conditions. How are they able to determine sub-inch accuracy? This sounds impossible, even with "25 extra-precise GPS receivers" as stated in the article. I just don't believe it is possible to measure to this level of accuracy with GPS. Someone please prove me wrong and school me how to build one with this accuracy for my autonomous lawn bot :)
    • Re:GPS Accuracy (Score:5, Interesting)

      by BitterOak (537666) on Tuesday January 17, 2012 @09:23PM (#38733668)
      They probably use techniques like differential GPS [wikipedia.org] to increase their accuracy.
    • by Formalin (1945560)

      Good question, I came to post this too. Mod parent inquisitive.

      AFAIK the fed can enable the higher-accuracy bit on GPS, but I don't think it is anywhere near 1/40th of an inch accurate, like TFS impies.

    • by tomhath (637240)
      A couple of years ago some coal miners were trapped underground in Pennsylvania. They brought in someone with super expensive GPS equipment to locate where to drill the rescue hole. As I recall he claimed he could fix the position within a few centimeters. Anyway, they drilled where he said and hit the chamber where the men were located, so he was either very good or very lucky. But don't expect your phone or other (non-special-government licensed) consumer device to be much better than a few meters.
    • Re: (Score:3, Informative)

      by Shavano (2541114)

      You use 2- frequency GPS receivers that are inherently less noisy and more accurate than the cheap ones everybody uses for coarse navigation. Then you average the position data over long times.

      The longer you average, the lower the uncertainty in the position.

      • by Shavano (2541114)

        There's also the point that this inherently a differential question. They use simultaneous data from two receivers that see the same satellites at the same time to solve for the difference in position rather than the absolute position of each receiver. You can do this for each pair in their set of 25 receivers or for any subset.

        Fancy math: cool answers.

    • If they use military-grade GPS systems they can get sub-inch accuracy. All everyone else can get a lot less accurate. One of the reasons China is putting up their own satellite constellation for the own GPS-type system, so they can achieve the same accuracy our system has. I suspect they either can't crack the coding to use the more accurate system, or more likely they have cracked it and reverse engineered it.
    • by imidan (559239)

      Stationary GPS is a little bit different. The receiver is planted in a location whose coordinates can be very carefully determined via more traditional survey methods. Combine this with some other technologies, and you can get very precise and accurate results. For example, one of the factors that degrades the accuracy of GPS is atmospheric effects. With a network of carefully surveyed stationary GPS units, we can correct for atmospheric effects by seeing how 'off' the various units are compared to normal,

    • Re:GPS Accuracy (Score:4, Interesting)

      by dido (9125) <dido@@@imperium...ph> on Tuesday January 17, 2012 @09:45PM (#38733848)

      Differential GPS [wikipedia.org] gets accuracy to up to 10 cm, which is just above 4 inches I think. It seems that it is possible to obtain even sub-millimeter accuracy [nxtbook.com] from GPS, although I gather the techniques used aren't real-time, and as such unsuitable for mobile robotics. :( They work well enough for surveying though.

      • Re: (Score:3, Informative)

        by maroberts (15852)

        I was working for a company on differential GPS back in 1992 and we were obtaining precision of less than a centimetre for differential GPS even then, real time. Admittedly "real time" was only about 1 update every 5 seconds or so but that was good enough for surveying purposes. Also we were generating an atomic reference clock using GPS to correct the receiver oscillator. If the resulting time signal was good enough for radio astronomy at Jodrell Bank, I presume it was good enough for anyone.... We were us

        • by Muad'Dave (255648)

          We were using 68000 processors...

          Wow - you really did imagine a Beowulf cluster of ... oh, you mean Motorola 68000 (tm) processors. Drat!

      • by tokul (682258)

        to 10 cm, which is just above 4 inches I think

        2.54*4 = 10.16 cm
        below 4 inches, if your below and above don't reffer to accuracy.

    • Differential GPS, as BitterOak said, as well as some exotic techniques of receiving the GPS signal, as well as certain signal processing approaches - you're measuring distances over a year; there's a lot of processing gain if you simply take a million readings and average them!

      There's a good chart here http://www.geoplane.com/gpsneeds.html [geoplane.com] showing the cost curve as accuracy goes up.

    • Re:GPS Accuracy (Score:5, Informative)

      by oneblokeinoz (2520668) on Tuesday January 17, 2012 @09:50PM (#38733886)
      The key thing is that this level of accuracy is not achieved in realtime.

      The receivers would be recording more than the information contained in the GPS messages, they would be recording phase and signal strength data for all the satellites in the visible constellation.

      Sophisticated post processing software would combine this information across multiple receivers, along with published satellite ephemeris data, to produce an accurate position solution.

      Realtime positions cannot be that accurate due to affects like ionospheric refraction etc.

      I used to work with a mobile system that recorded the GPS data along with inertial information (at 200Hz) that in realtime gave a solution that was usually accurate to within 30cm, and got to better than 10cm when combined with static ground station data in the post-processing step.

      There are systems used in agriculture that are very accurate (10cm-ish) that use differential-GPS in realtime. The trick is your mobile unit has to be in constant communication with the differential ground station. Works ok for tractors, not so well for an aircraft 200-300km away. For differential-GPS to work well both units need to see the same satellites.
      • Thank you, I wish I had mod points... This clears up some questions I had about GPS. I have been trying to use a fixed point (known location) as a starting reference, but I could never come up with an %-error calculation for the Long/Lat as I moved away from that position. Additionally both the %-error and position and it would drift each day and even averaging the data over time never got close to plus/minus 10 feet. I have since switched to gyros, magnometers and accelerometers but they have their issu
        • I was living in the US at the time when "selective availability" was turned off. This was the deliberate manipulation of the non-military GPS signals to make the position solution less accurate.

          I set my laptop up to record and plot my position on the night it was disabled, using a Delorme GPS. The next morning it showed a wide green wandering star-ish shaped track roughly around my house in the early part of the recording, and just a steady green blob for the later hours. I wish I had bothered to be mo
        • by tibit (1762298)

          You should have perhaps asked someone who knows a bit about it, since those are all problems with known solutions. A GPS receiver that you can buy for less than USD $1k won't give you anwyhere near the accuracy you can pull out of the signal in realtime without using any differential techniques at all. For about $15-$20k in gear (multifrequency receivers with phase processing and ionospheric correction, large antenna, etc) you can get a couple mm of error in real time. Add to that another "nearby" receiver

          • by adolf (21054)

            Be prepared to spend good money for that. A good car's worth.

            What's a "good car" worth? Are we talking H1 Hummer, Pagani Zonda, or a Kia Whatever?

            They're all "good cars," in that they're all solid and reliable, and are also optimized for their purpose.

            So please forget the car analogy, and use a value that people can actually relate to. (Dollars would be adequate.)

            • by ThePeices (635180)

              Hummer? Kia?

              He said a "good" car.

    • by mini me (132455)

      The RTK receivers used to power much larger lawn bots (i.e. farm equipment) claim 1-2cm accuracy. They are quite expensive and require correction data from an external source; either a base station or a subscription with someone who will provide the base station date, typically over IP. With a decent budget, it's definitely possible though.

    • Isn't consumer GPS artificially liimited in accuracy? I thought the military and government versions were much, much more accurate...

      • by Wingman 5 (551897)

        Isn't consumer GPS artificially liimited in accuracy?

        Not artificially, economically. It costs a LOT more to get real-time sub 1m accuracy without post-processing. For what you are using the gps for (navigating a turn on the street 90% of the time) 1-5m accuracy works fine. You can buy high end equipment (we are taking more than $1K) and get realtime data in the 1 inch range. For 10-20K you can get to the millimeter range.

        Which would you buy to use in your car, the $50 GPS, or the $900 gps with the only additional feature it has is if you go to the menu that

      • by imidan (559239)

        It used to be artificially limited (they called it 'selected availability'). Today, US GPS has selected availability turned off, so civilian GPS users have access to the same data as the military. I don't believe there's any technical reason why they couldn't turn it back on, but GPS has proved to be so useful for civilians that it'd probably have to be a pretty serious situation that would prompt them to do it.

    • When you drive around, you get to see a couple of sats for a few seconds, and then your position has changed again. If the receiver knows it is bolted to the floor, it can track satellites for hours and calculate very nice averages.
    • by Jonner (189691)

      Extremely accurate GPS fixes needed for tasks such as this need many samples without moving the receiver and sometimes use ground stations with known positions.

  • by Anonymous Coward

    Airplane quote for the win!

  • This is news? (Score:5, Insightful)

    by QuasiEvil (74356) on Tuesday January 17, 2012 @09:37PM (#38733764)

    Seriously? The entire Rio Grande Valley - which pretty much covers a north-south line right down the middle of the state - is a rift valley. The continent has been splitting and spreading here for millions of years. It's an interesting measurement, to be sure, and it's nice to have confirmation, but it shouldn't come as much of a surprise.

  • the state is unquestionably expanding

    By definition, New Mexico lies between the 103 W and the 109 03' parallels (mostly [senate.gov]). The only way New Mexico could be getting wider is if the earth's radius is increasing, pushing the meridians apart. Since Arizona is bounded on the west by primarily by rivers, maybe it's the one getting wider (or Arkansas!)

  • So is a "nanostrain" equal to 1/40th of an inch? That seems too big for the nano prefix.
    • by tibit (1762298)

      Nanostrain is a unitless unit. It means 10^(-9) in/in -- inches per inch. It's a relative measure of deformation, it always needs to be a applied to a length to give length. Just to look at orders of magnitude: 10 nanostrains over 100 miles = 10^(-6) mile = 0.6 in.

    • "Strain" is expressed as length divided by length (e.g. in/in). In other words, it's a dimensionless ratio. Here's how we calculate it for this situation:

      The length (actually width) of New Mexico is about 343 miles, which is 21,732,480 inches:

      L = 2.1*10^7 inch

      In a year it stretches 1/40 of an inch (on average):

      dL = 2.5*10^-2 inch

      Therefore the strain, dL/L is:

      dL/L = 2.5*10^-2 inch / 2.1*10^7 inch = 1.2*10^-9

      Voila: the inches cancel and you get 1.2 dimensionless "nanostrains."

      • By the way, I ignored it by considering only a single year, but what I really calculated was the average strain rate, with units 1 / year (i.e., the answer is really 1.2*10^-9 year^-1). Weird, eh?

  • The earth is trying to get away
    From the New Agers in Santa Fe

  • Louisiana is losing ground fast. Some parishes will be almost entirely water pretty soon; the basic problem is that the way we're artificially keeping the Mississippi's course stable is sending all the silt off the continental shelf when it should be helping to reinforce the delta.

    Maybe to mitigate the inevitable cost of cleaning that state up the next time a hurricane blows through we should give strong incentives for people to move to NM where the ground is growing rather than getting eroded into the ocea

  • ...what about Brooklyn [youtube.com], then?

  • is this will trigger another terrible Roland Emmerich disaster movie.

  • The Rio Grande rift is a classic extensional (expanding) zone. Downdrop valleys and volcanics.
    • I agree, the Rio Grande Rift is well known and you have a clear and visible history of recent past volcanism in the areas in and around it in New Mexico. About the only thing new in this article is it listing the speed of expansion based on GPS data.
  • An interesting theory by Neal Adams is that all planets grow...
    http://www.nealadams.com/nmu.html [nealadams.com]
    Perhaps the energy in the core of the planet gets converted into mass. My guess is there are lots of places on the planet that are "growing".
  • so is my midsection! ba-dum-ching!
  • At least my decendants will have a place to pay taxes on.

  • by cshark (673578)
    Sounds like another proof for the "expanding earth" theory. Interesting stuff.
    • This is no proof at all for the "expanding earth" theory. The thing is, elsewhere on earth, you have crust being subducted and remelted into the mantle.

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