Good or Poor?

[Bill93]

I found this one yesterday. It was a 2nd order horizontal mark set in 1970 by USGS as part of their work to complete topo maps of the area. It is a disk on a rod in a clay tile (broken). The tile is now pushing against the rod and slightly moving the disk horizontally. Is that Poor because the disk isn't exactly in its original position, or Good because a surveyor could dig out around it and find the position of the main part of the rod?

 

I've seen worse, and generally find this type to frequently look questionable.

 

I'm not sure why it is so high above ground. Did frost raise it in 39 years? (Don't know length of rod) Or did somebody try to pull it up but not all the way out? Or did that much dirt get removed, which doesn't look too likely from terrain?

Edited June 1, 2009 by Bill93

[+t8r]

I'm going to guess, as a non pro here, that a surveyor would not trust this one.

Too many variables here. If the rod only extends deep enough to allow frost heaving, it could have been pushed over more than is obvious.

Too many other options these days. I've been watching local surveyors, and they seem to have their favorite station upon which to set up the reference transmitter, on a high spot, outside of town that is not likely to be disturbed.

Remember, this was set flush with the ground. It will be interesting to see the professional input here.

 

There seem to be some really stable vertical stations, deep rod with lid, that have been used by local engineers for horizontal reference. They have the precise coordinates and do not always share them.