USC&GS overstamping USGS disk

[+LSUFan]

One of my geocaching/benchmark friends sent me a question about a benchmark he found which is EH0329

 

It appears that the USC&GS in 1934 sort of took over a USGS mark possibly from 1908. Below is my answer to my friend, but I wanted to let the experts here take a look to see what your thoughts are on it. I had never seen this scenario before. I have also never seen a USGS disk set in a post with this kind of inscription either.....but I don't get out much.

 

Any help would be appreciated.

 

Here was my reply:

 

Richard, that is an interesting one, no doubt.

 

Just looking at the disk itself, shows some peculiarities. It is a US Geological Survey(USGS) disk, who are the people who make the topo maps. What is odd, is that the US Coast and Geodetic Survey (which is now the NGS) stamped this USGS disk with their initials and converted it into one of theirs in 1934. Can't say I've ever seen that before. IMHO, I don't think the disk was added later (1934), but was originally there in 1908 and then overstamped in 1934.

 

The designation itself, G30, tells me that is most likely part of of level line run. Looking at a map, you should see other marks in a line with the same 30 stamping, but the letter of the alphabet changed. Ex: A30, B30...Z30. They will usually follow roads, rr tracks, etc.

 

 

The fact the concrete post itself, is engraved with USGS #3 leads me to believe that in 1908 it was possibly part of a triangulation station.....maybe reference mark #3. I can't really tell if the disk was stamped with anything in 1908, or if the #3 could have just came from the engraving in the post. If the disk was mostly blank, that may be why the NGS put their stamp on it in 1934. Not sure on this part though.

 

 

Problem with USGS marks, is that they don't have any online database to search for active or destroyed marks. All of their info resides in filing cabinets in their regional offices, which you can send emails or make a call to...and they will do a search and send you the results.....if you want to attempt to find out the history of the original disk from 1908. Here is a link on how to do this:

 

http://gallery.usgs.gov/audios/130#.UF98XqDN6So

 

However, any mark (including USGS ones) that the NGS bluebooks for use in the National Spatial Reference System (which is what you see on gc.com) are in the online database maintained by the NGS, which you are reading the datasheet for, from the point the NGS accepted it (1934)

 

If you don't mind, this would be a good one to show my buddies out in the national forums...to get their take on it.

Edited September 23, 2012 by LSUFan

[+LSUFan]

If you don't mind, this would be a good one to show my buddies out in the national forums...to get their take on it.

 

Isn't this a national forum?

 

Yes. I was telling my friend I was going to post it here.

[kayakbird]

LSUFan,

 

I think that this took place rather frequently:

 

JN0016 DESIGNATION - E 11

---

---

JN0016'WEST ABUTMENT. A UNITED STATES GEOLOGICAL SURVEY STANDARD DISK,

JN0016'STAMPED 4062.

 

ALSO PASTED IN A RECENT THREAD HERE

 

 

And one in Eastern Oregon:

 

PA0352 DESIGNATION - U 18

---

---

PA0352'UNITED STATES GEOLOGICAL SURVEY STANDARD CAP, STAMPED 4203 U 18 H 1903

 

HARNEY CO, OREGON

 

 

Seems like I noticed logs or Datasheets of others in Oregon. Need to CSI the center to see what somebody spent a lot of effort to mostly hammer out on yours - I think that I see the 'EL' OF 'ELEVATION'.

 

kayakbird

[kayakbird]

And sticking my neck out a little bit, I would like to CSI the chemical composition of this large diameter, ONE INCH,

 

copper bolt to verify that it is Clarence King's CHALK BUTTE of the 1867 Fortieth Parallel Survey which

was end stamped USGS at some time and enhanced with CGS RM's in 1938. MEL

[+LSUFan]

Thanks Mike. Any suggestions on what the No. 3 means, on the post?

Edited September 24, 2012 by LSUFan

[southpawaz]

Thanks Mike. Any suggestions on what the No. 3 means, on the post?

 

I'm guessing from my limited experience with USGS marks around here from that era that it's not the numbering of a reference mark for a triangulation station, since I don't think they were monumenting a lot of RMs. A few stations that come to mind: CG1052 single reference mark, chiseled cross (though that monumentation type might not have been appropriate for the area where this one is); while these three DU2086, DU2276, ET0856, each had no USGS reference marks set.

[kayakbird]

Thanks Mike. Any suggestions on what the No. 3 means, on the post?

 

Bobby,

 

I would guess that there was/is a sequentially numbered series of marks with the same style of setting.

 

Came up with this one 45 miles north:

EH0014 DESIGNATION - CONCRETE MON 1

-------------

EH0014 HISTORY - 20030409 GOOD USACE

----------

EH0014'THE CENTER LINE OF A PAVED ROAD. AN ALUMINUM DISK IN TOP OF A LARGE

EH0014'CONCRETE POST WITH LETTERS MISS 1908 CAST IN THE SOUTH FACE OF THE

EH0014'POST AND USGS NO 1 ON THE NORTH FACE OF POST WHICH PROJECTING 2 FEET

EH0014'ABOVE LEVEL OF THE GROUND AND 2 1/2 FEET ABOVE LEVEL OF THE ROAD.

 

There is something on GE bearing 204D 30M 112 FT from where it pegs.

 

Did not see any others 'Placed By' CGS in 1934 in the counties along that line with anything in the description that sounded like a tapered concrete post. Did not work further south. Am I seeing an older levee/drain system more or less parallel to the line between the two points? Maybe USGS did a special level run for map control for a USACE/COE/USED project?

 

Sometimes a good NONPID mystery mark is more fun that what can be logged/recovered. MEL

[+LSUFan]

 

There is something on GE bearing 204D 30M 112 FT from where it pegs.

 

 

What an eye you have, Mike! I saw what you were talking about in the aerial view. That is the mark, which you can plainly see the tapered post when you take google earth all the way down to street view. I'm impressed.

 

Edited September 24, 2012 by LSUFan

[kayakbird]

#4 may be visible also - and it was recovered GOOD in 2006.

 

DK0022 DESIGNATION - 4 USGS

 

--------------------------

DK0022'AND NUMBERS USGS NO. 4 ARE CAST ON THE NORTH SIDE AND MISSISSIPPI 1908

 

MEL

[+LSUFan]

Kayakbird and Southpawaz, thanks for the help and education. As always, ya have helped out tremendously.