Four Corners Monument in da wrong place (Dona Ana: lawyer, transfer)

[mike0421]

Originally Posted by denverian

I've noticed that the state lines on square states are anything but straight, if you look at the satellite view and zoom in. They're quite crooked.

Example:


Look at that big "oops"! That error was a result of the Mason-Dixon survey.

[Poncho_NM]

That is because the earth is curved and you are trying to view it on a flat display. Ever notice those airline brochures which showed curved route lines? They aren't really curved lines, they are actually the shortest distance between two points. Google Great Circle


Rich

ADDED: Also issues like Mike pointed out below. Also image resolution could cause jagged lines. etc

[mortimer]

The point is only off by 2.5 miles.

When I said move the border, I meant just let the lines 'jog' over for about 3 miles or so. If any state is worried about losing territory, then there could be a compensating 'jog' in another location.

If it sounded like I was proposing moving borders over by 2.5 miles along the entire length of the states, that wasn't my intent.

Naturally, what will end up happening is we'll just use some stimulus money to physically move the monument.

[mortimer]

Poncho on globes:

> That is because the earth is curved and you are
> trying to view it on a flat display.

I always found it fascinating that when taking off from Los Angeles - heading for Taiwan, the plane would fly just off the coast of San Francisco so that I could observe the Golden Gate bridge and then later, 3 hours out, I could look down on Japan. I have pictures of Mount Fuji from the plane.

[Lovehound]

Originally Posted by Poncho_NM

That is because the earth is curved and you are trying to view it on a flat display. Ever notice those airline brochures which showed curved route lines? They aren't really curved lines, they are actually the shortest distance between two points. Google Great Circle

ADDED: Also issues like Mike pointed out below. Also image resolution could cause jagged lines. etc

No, that's not it at all. The map that Mike showed is actually an historic map showing the border that Pennsylvania claimed in historic times. The modern border includes the odd shaped sliver of land as part of Delaware.

You can get a better understanding by reading these two Wikipedia articles: (1) the Wedge, and (2) the Twelve Mile Circle. As Mike stated, the original confusion was caused by Mason's and Dixon's surveying inaccuracies compounded by the fact that Delaware was originally part of Pennsylvania and when the two became separate the border was poorly defined. It took until 1921 to settle which state included the wedge: Delaware.

[Lovehound]

The more I research this topic the more interesting it gets. The first time I went to Monument Valley after getting GPS (I've been to MV about a dozen times) I noticed that the border was in the wrong place. I had traveled up Highway 163 from Arizona to Utah and I noticed that the state border was incorrectly located about 1,000 feet south of 37° N. I was puzzled and assumed that my GPS must be a bit out of whack.

Today when writing posts for this topic it dawned on me that the border was in the correct place and that I had been mistaken in thinking it was 37° N. Most maps (eg. AAA) show the border along the 37th latitude. You can tell by looking at Google Maps that it isn't that at all. You can even see a place about 10 miles west of Highway 163 where the UT-AZ border takes a kink! I presume that west of the kink the border actually is 37° N.

Curious observation: To get to Monument Valley from Arizona on Highway 163 you have to go to Utah and take the turnoff which leads to Monument Valley... which is located back in Arizona!


Getting back to Four Corners, it's surprising that nobody noticed it wasn't in the expected place sooner, considering that many people have GPS. I presume that is because most people leave their GPS on the road map display. I've been to the Four Corners Monument only once, before I had GPS, so I never noticed that the monument was in the "wrong" place.

By the way, the entrance fee to get into the monument was the most wasted dollar that I've ever given to a Native American. (It was a dollar to get in when I went.) There is nothing interesting in the area except the area where the state boundaries are inscribed. It takes about 5 minutes to see every last interesting detail about the monument.

I advise tourists to spend the few hours it takes to get to Four Corners Monument doing something else more productive. Unless of course you're driving along Highway 160 intending to go to some other destination. It might be worth the half mile detour and 5 minutes if you're not driving out of your way.

[Poncho_NM]

Originally Posted by Lovehound

No, that's not it at all.

I have stated the three possible reasons. And I guess you could come up with other reasons of why there would be "crooked" lines. Perhaps denverian can define what he/she means by "quite crooked" lines...

I was using GPS with the Department of Defense during 1980 if my old/tired memory is accurate, before they were released for civilian use and bought one of the early civilian units for aircraft use.




Rich

[desert sun]

four corners from google

Link: <Google Maps>

[jazzlover]

Originally Posted by mike0421

There are a bunch of points I have to make regarding this thread. I'll start with Mortimer's assertion of moving the borders to reflect the actual location of the monument. This would seem rational and logical, however, many more borders also have to be moved. The four corners survey actually post-dates many others that were made in this country that define modern day boundaries, including the most high profile survey, the Mason-Dixon survey. If all surveys today were re-done based on ancient title deeds, there would be much litigation in the federal courts.

I will try not to bog this part of my post down into highly technical jargon, so here it goes: the four corners survey was conducted using a completely different datum than the one that exists in the present day. A datum is essentially the reference specifications of a measurement system, in coordinate positions, either horizontally or vertically. The datums that have been used over history have varied, being superseded by superior measuring techniques. These techniques evolved over time as geodetic scientists were able to garner an appreciation for the shape of the earth. In the beginning, the earth was thought to be a perfect sperhoird, but over time, the x and y flattening and orientation was taken into account: the earth bulges out more at the equator than at the poles. Therefore, the distance from the north pole to the south pole is shorter than is the distance from Greenwich meridian to the International Date Line is, at the equator. This was not acknowledged in the 1800s.

The state of New Mexico conducted its own survey in the 1920s, to divide the state into logical land parcels for undeveloped land. (There are outliers in this survey, such as metes and bounds for Spanish and Mexican land grants that shatter the gridiron pattern) This survey was conducted using another geodetic datum, in this case the North American Datum of 1927. This datum is applied for the lower 48 states, and assumes a known point in Meades Ranch Kansas, the geographic center of the lower 48 states. Herein lies the initial likelihood for discrepancy.

Now consider, in chronological terms, all the land boundary surveys that have been conducted since colonial times, and how they vary, as time goes on. The Clark survey conducted that measured the New Mexico-Texas boundary was more than 2 miles inaccurate, as later proved. This survey occurred in 1859. Subsequent to that survey, the proper 103rd meridian was uncovered to survey the Oklahoma-New Mexico boundary. If you zoom into the point where the three state boundaries converge, you'll observe a 2 mile offset between these boundaries. Yet, it is rarely remarked upon or even observed.

As a final observation, going back to the PLSS survey, I possess data where survey monuments are SUPPOSED to reside, using the 1927 NAD survey markers. However, in 1980 the International Union of Geodesy and Geophysics refined (once again) the criteria in which datums are callibrated. Previously, these datums were callibrated from a known point on the earth's surface. The geodetic reference system of 1980 redefines this criteria. The datums now commonly used are now geocentric, which means that now, rather than the point being derived from a known point on the earth's surface, now, the horizontal geodetic datum based on an ellipsoid that has its origin at the earth's center of mass. The reason for doing this was to accommodate at that point the emerging technology of satellite positioning systems. Why do I mention this? Because I have had the pleasure of converting the NM survey monuments, conducted in the 1920s and 30s, derived from the NAD 1927 datum, into the NAD 1983 datum, which is formulated from the GRS 1980. If I convert these monuments into waypoints and navigate to them, they are RARELY where they should be. The tolerance threshold is typically anywhere between 3 and 50 + feet.

I only offer up this post to illustrate how inexact our entire U.S. land boundaries are. This article is not surprising, in fact, given the history and evolution of survey techniques, it should be very understandable.

Great post. As I said earlier, the surveying and geographical community has known for years that the Four Corners Monument is not at an accurate location, but--as you point out--there are few section corners, etc. that are, either. Since the monument is the legally accepted point where the four states meet (along with the state boundaries emanating from it), neither the monument nor those state lines are going to be moving--not unless a Federal Court judge decides to decree that they will.

I am not a surveyor, but I work with these issues on nearly a daily basis in my work. Just one of those "ho-hum" things that people don't think about until somebody makes a news story out of it. So, if you lay down sprawled across the Four Corners monument, are you in four states at once? Geographically, no. Legally, yes.

[Lovehound]

Originally Posted by Poncho_NM

I have stated the three possible reasons. And I guess you could come up with other reasons of why there would be "crooked" lines.

Um? I thought that I did that (above).

Originally Posted by Poncho_NM

I was using GPS with the Department of Defense during 1980 if my old/tired memory is accurate, before they were released for civilian use and bought one of the early civilian units for aircraft use.

I was interfacing GPS to the US Army TACFIRE artillery system in 1969. I recall at the time being amazed at the $25,000 or $50,000 units and hush-hush, and remember that I wished that this technology could become available to ordinary citizens. I thought then, like oh yeah, ordinary people could ever afford that much to buy a GPS unit.

Yet in the early '90s (that I remember) civilian prices came down after access was granted, and I bought my own first GPS in '95. I never guessed that it would go from (guessing) $50K to $500 in mid '90s, and down to slightly more than $100 now. (Maybe there are sub-$100 units.)

I'm just waiting to get my own spy satellite and ICBMs!