We’re trying to stake a well location, and for the purposes of saving some location costs, the operations guys want to move this well 100 feet. Fine - usually not a problem, but I’m still cooling off the embers from the 250 foot location move that I was not consulted about that faulted out our primary objective with a fault that I had picked. So, we’re gonna check it even if it probably means little or nothing.
So our engineer gives me new coordinates, generated by a field guy with a GPS unit. They are written in the form:
N *##*º 03.891 ft.
W *##*º 57.368 ft.
All of the software I use wants lat-longs in decimal degrees or degrees minutes seconds. The above does not jive with either. The geologogist, the engineer and the landman don’t know what to make of it. If I ignore the annotation indicating units in feet, I can make it sort of make sense if I assume it’s lat-long in degrees decimal minutes. The worrisome thing there is that a.) I don’t know definitely that the surveyor and I are working the same problem and b.) that moves the location WNW instead of the SSW the surveyor indicated.
So, the question for the GPS using folks would be: is degrees decimal minutes a format commonly used? We’ve never seen it before, and none of our software likes it, but that is the only interpretation of the above data that makes sense (we are going to get a resurvey in language we speak - I’m just curious here).
All the GPS units I’ve used, and I’ve used quite a few, display one of two ways:
A. Degrees - Minutes - Seconds or
B Degrees - Minutes - decimal of minutes.
Some GPS units allow you to change the display to how you want it. I use it in a maritime environment, so I’ll display whichever format that matches the type of chart I’m on. I’ve never seen a format which places “ft.” at the end in your example.
Assuming that your display is reading minutes and decimals thereof, converting to seconds is easy should that better suit your purpose, and the unit won’t do it automatically.
To convert decimals to seconds, multiply by 6.
As in 44-35.500’ .5 x6=30 44-35’30"
From seconds to decimals, divide by 6.
FYI, you can measure distance on your Lat scale if you didn’t know that already 1 minute of Lat=2000yds or 6000ft or 1nm
It’s obviously decimal minutes and the guy didn’t recognize the annotation for minutes, so he wrote down ft. The conversion’s not a problem, I just don’t like to make possibly costly assumptions.
Ah yes, I see where he got the “ft”. The short answer to your OP question is yes, that format is very common. At least it is in the maritime environment.
Considering that someone’s mistaking the ’ in a GPS readout as “ft”, and not minutes, your resurvey seems a very wise idea indeed.