Interesting Pids

[+BuckBrooke]

Here's an interesting cluster of stations for someone to find in Kern County, CA.FU2776 LOST 2, which has nearby PIDs LOST RM 2, LOST 2 RM 3, LOST 2 RM 6, LOST 2 RESET, LOST RESET, LOST AZ MK 2, and who knows how many more marks, all at one intersection.

 

Has anyone else ran across large clusters of PIDs, either ones that they've found, or not found? While we've had a bit of this discussion before, I find places like this interesting, that are target rich and you can see the surveying history by the placement of the multiple disks. They're easy enough to find in your area by using the other search option and searching for RM 2, RM 3, RM 4 ... RM 10, and searches for marks up to AZ MK 5.

 

Does anyone else have good locations, or search strategies?

Edited May 26, 2005 by BuckBrooke

[kc2ixe]

Yeah - look in the area of KU3502 - there are 6 or 7 pids in a couple of hundred meter radius, and that whole area is riddled with BMs - heck, I recovered 5 this weekend - 2 not entered, because I'm not sure what to enter

[+Me & Bucky]

On the grounds of the USGS office in Flagstaff, Arizona, there is a horizontal control disk FLAGSTAFF NCMN (PID FQ0454) with 4 Reference Marks. The Azimuth Mark is about 4/10 mile to the east.

 

Found 4 of them, with one DNF and a Note on the Azimuth. Probably the DNF should have been a Note as well, since I wasn't able to search the actual location.

[evenfall]

Me & Bucky,

 

Interesting to see an AZ Mark off to the east of the station. The practice was that they were attempted to be placed to the south. I looked at Photos and it appeared that buildings in the area may have prevented that practice form being practical.

 

If the NGS Datasheet is pulled, we can see that this station has photos. In three of them we can see the GPS Antenna and receiver mounted on the tripod above the station. one photo shows a Long cable is stretched from that back to the comfortable, air conditioned Suburban where the Party Chief can monitor out of the HOT Arizona Sun. That is the way to do it!

 

Another Interesting thing about that Station; It is an A order Station, but rather than being as such by way of GPS observations, It was done with VLBI (Very Long Baseline Interferometry) which is no where near as commonly done.

 

Thanks for sharing!

 

Rob

[+BuckBrooke]

I have experience of interferometry and VLBI techniques from observing in radio astronomy with the Very Large Array and reading about the VLBA. What's the setup for GIS surveying use?

Edited May 27, 2005 by BuckBrooke

[holograph]

BuckBrooke,

 

Take a look at this PDF document from NASA, specifically pages 27 and following. It figures that not much of this is done nowadays, with compact, portable GPS equipment giving better results.

 

If you Google for "mobile VLBI" you see a lot of overseas pages, and almost no US pages. I saw one page that mentioned that "NASA discontinued mobile VLBI observations" some years ago.

[evenfall]

Buck,

 

It is a lot to read, But Nasa is still at it, the website is here:

 

http://lupus.gsfc.nasa.gov/vlbi.html

 

Enjoy, it is a good read.

 

Rob

[holograph]

Right, VLBI is still an essential part of establishing the reference frames. NASA used to have a program called the Crustal Dynamics Project (CDP) that used the mobile trailers to acquire VLBI data at places that didn't have fixed radio telescopes. It's those mobile operations that were discontinued. VLBI geodesy from radio telescopes is alive and well.

[+Spoo]

Route 25 on the ME-NH border........

 

There are about 25 NGS, CGS and USGS (countable) marks all within a 5 mile radius. There are also numerous ME DOT, NH DOT and ME-NH SURVEY marks within this area.

 

I am still looking for some of these.

 

For those interested, center your hunt at OC0569.

[+Bos]

TRIANGULATION STATION NICEVILLE

http://www.geocaching.com/mark/nearest.asp...&lon=-86.517211

 

HISTORY Near as I can reckon. Twelve marks total. Seven probably missing. Five survive. (Three in good shape. Two hit pretty hard.)

 

NICEVILLE Triangulation Station - set in 1934 - Destroyed by highway construction, 1970. Reset nearby as Niceville 2. Data sheet is hard to find but makes interesting reading.

http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=BG3383

 

NICEVILLE 2 * Triangulation Station - Replacement for above station. Set in 1970 about 37 feet NW of the original 1934 Niceville site.

 

NICEVILLE RM 1 - 1934 - Reference Mark for Niceville Triangulation Station. Destroyed by construction of highway 10 (now SR 85), 1945. Replaced by RM 3.

 

NICEVILLE RM 2 * - 1934 - Reference Mark for Niceville Triangulation Station and for the reset Niceville 2. Two data sheets - one adjusted (listed coordinates accurate) , one scaled (listed coordinates approximate).

 

NICEVILLE RM 3 - 1945 - Reference Mark for Niceville Triangulation Station, set as replacement for RM 1 when RM 1 was destroyed by highway construction - data sheet says this was monumented as a Triangulation Station Disk in 1957 and stamped Niceville No 3 1945. Destroyed by highway construction, 1970.

 

NICEVILLE RM 4 * - 1934 - Reference Mark for Niceville Triangulation Station and the reset Niceville 2. Although disk is stamped 1934 its data sheet says it was set in 1955 - and the data sheet for the original station Niceville says RM 4 was set in 1945.

 

NICEVILLE RM 5 - 1964 - Reference mark for NICEVILLE Triangulation Station. Certified destroyed by land clearing operations, 1970.

 

NICEVILLE 2 RM 6 * - 1970 - Reference Mark for Niceville 2 Triangulation Station.

 

AZIMUTH MARK NICEVILLE - 1934 - Moved in 1942 due to highway construction. Same disk was used with 1934 removed and restamped 1942.

 

AZIMUTH MARK NICEVILLE RESET - 1942 - Reset of moved 1934 Azimuth mark. 1945 recovery note says this mark was destroyed.

 

AZIMUTH MARK NICEVILLE Reference 2 - 1945 - No data sheet found. Set to replace the above azimuth mark. Destroyed by highway construction, 1970.

 

NICEVILLE 2 AZ MK * - 1970 - Present day azimuth mark for station Niceville 2. Mark moved slightly and witness post destroyed during land grading for a fence in September 2004.

 

* - Known to still exist. The others are believed destroyed.

[+Harry Dolphin]

I see nine listed at this location:

Brigantine Bridge. Isn't this what people go to Atlantic City for?!?

 

I was checking NGS for a planned visit to DC, and found something like 25 benchmarks inside the US Capitol. Of course, I wouldn't be able to get near any of them. Oh, well.