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Single point Basis of Bearing
Posted by ridge on January 6, 2014 at 6:55 pmNever seen this one before. Plat just lists an old USGS point as the Basis of Bearing. There is no tie with bearing from a corner on the plat to the point but the location of the NGS point is approxametly shown as about SW all the way across a section plus some (maybe 8000 feet). I know where the USGS point is.
So I don’t know, maybe close to astronomic or NAD27 geodetic?
Here is a portion of the plat from 1980:
T.P. Stephens replied 10 years, 7 months ago 16 Members · 26 Replies -
26 Replies
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Your guess is as good (or bad) as anybody else’s.
Talk about crappy (virtually non-existent) metadata…
Tie in Hilltop-1938 and a few of this yoyo’s “corners,” and let us know what you find out.
Man I hate that kind of crap…
Loyal
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That’s where the little doggie, did his rotation thing, (N-S) and determined north to be!!!
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:good:
Triangulation station with published bearings to other stations or reference marks?
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He doesn’t show any record vs. measured bearings on anything recovered on his plat that might provide a clue? Just seems a little far fetched to me he’d use an azimuth point off a USGS station to wing a point out 8000′ and not show that tie.
Willy -
Now that’s funny; an early version of “Bearings are GPS”. I’ve got to think it’s state plane, they probably used an AZ mark or water tank or something on the old data sheets
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I tried to call his morning, left a message. The guy just retired from the head of a state agency (not surveying). I’m more interested in what if anything was set at the corners so I’d know what to look for. These subdivisions in Utah from that time period could be anything from nothing (paper lots) to wood hubs or if you are lucky a short steel rebar or really lucky a steel tee post (shows above ground). The plat doesn’t say what if anything was set at the corners (typical for the time). I should be able to find the fences shown though (get me started).
This area is covered with juniper trees and Gamble oak (very hilly). It would have been difficult the old way, cutting sight lines and pulling a tape. Even with a distance meter still would have been trouble cutting sight lines. I don’t expect the corners will be all the precise. So it will be resurveyed a few lots that miss the original quite a bit. Then the original might be there, might not. I probably should pass on the job. Snow on the ground at this time, a five acre lot sells for 7-10 thousand, gonna be hard to get them to pay for a real survey.
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KN0382 ***********************************************************************
KN0382 DESIGNATION – HILLTOP
KN0382 PID – KN0382
KN0382 STATE/COUNTY- UT/SANPETE
KN0382 COUNTRY – US
KN0382 USGS QUAD – INDIANOLA (1975)
KN0382
KN0382 *CURRENT SURVEY CONTROL
KN0382 ______________________________________________________________________
KN0382* NAD 83(1994) POSITION- 39 45 12.36233(N) 111 29 24.98225(W) ADJUSTED
KN0382* NAVD 88 ORTHO HEIGHT – 1954.11 (+/-2cm) 6411.1 (feet) VERTCONEven state pain bearings wouldn’t be far off of “North” as the SP Meridian is at W 111 30 00
You’d need to pull the original USGS sheet to get any sighting bearings. The point is on top a hill. I suppose he could have set on it, sighted some reference noted from the USGS, then turned to a control point in the subdivision. Then from the subdivision back sighted the station and be on his way. It would get you close but still, state plane, NAD27 geodetic, astronomic, be nice to know, but no really big problem, just one I hadn’t seen before.
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> Never seen this one before. Plat just lists an old USGS point as the Basis of Bearing…..
The B.O.B. statement is obviously useless, but presuming that monuments were set at all those corners – and even a few survive – it is unlikely to affect the retracement. -
Never really care about a B.O.B. anyway. I’ll put true on anything I find and compare. What part of my true don’t you understand…. would be you’re problem.
Pablo B-)
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I don’t see where they are setting any corners based upon the symbols.
“Point in change in bearing”
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True
True: values based directly on astronomical observations. Geodetic Glossary – National Geodetic Survey
Do you make solar or polaris observations?
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There Is A Arrow On That Monument, So He Held That
Paul in PA
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Leon and Loyal… gidday from DU …the datum note is as useful as using the top of your boot toe as the mobile site bench mark…….where every player wins a prize.
RADU
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True
Both and with the sat stuff, depending how close to beer thirty it is. 😀 I got my certificate yesterday Jimmy…there’s only 40 of us left.:-O
Pablo B-)
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He shows a “point of change in bearing” symbol at the SW corner of Lot 39 but shows no change in bearing…. a straight line. So whatever exists at the SW corner of Lot 39 is probably different from what is at the next corner to the west, IF anything was set at either. It will be interesting to see results of what you find out there. I hope you get the job!!
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Angles & Distances Are What Matters, Bearings Are Relative
Rotating any description to compare it with true or an adjacent description should be second nature and never ever really worried about.
Paul in PA
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True
U.S. Mineral Surveyor certificate. Only 40 on the roster now.
Pablo B-)
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