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turning point?


rogbarn
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OK, I'm gradually understanding a lot more about surveying than I ever thought I'd now. But this one is new to me. See KK2045

Its Marker Type is "unmonumented" and in the description it says "turning point, needs no description". Perhaps another surveyor doesn't need a description, but I do! Can anyone interpret please?

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Turning points are used in Level Circuits which, in turn are used to determine an elevation of an unknown point from a known one.

 

If you envision a game of leap-frog, the first runner would represent the initial benchmark.

 

He runs, places his hands on the shoulders of the second person and propels himself over , landing running a bit and then crouching and waiting as the second person now stands and begins running to repeat the process. The second person, while crouching could be considered the turning point

 

Eventually the leap-froggers reach the end of the play area or tire out (the new benchmark).

 

So, to put it into a survey perspective, level circuits are seldom single set-up processes. You set up the level (the gun), hold a tape on the known benchmark and read the difference (generally as a positive value since we usually find the known benchmark on the ground.)

 

The person with the tape moves ahead to new point along the direction that you must go to reach the destination and places the tape there. The surveyor reads the difference and subtracts it from his running total, then grabs his level tosses upon his shoulder and marches past the man with the tape (or rod) and on toward the destination.

 

(Here comes the answer.. get ready..

 

ok.. so now the second person, holding the rod or tape TURNS to face where the surveyor went to his next setup.

 

And with that the process begins again (leap-frogging).

 

and that, students, is a TURNING POINT.

 

voila..

 

gil

ca_surveyor

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Rog

This is an unusually poor description. Check out the description of Sheep(1951), kk2044, referred to in kk2045, presumably the nearest marker to it. It is newer than kk2045, so I am guessing that they are not related, but it gives you some indication of the position of kk2045, since it is clearly labeled on the map. Look at the Bottle Pass quad on Topozone. This is a very remote area, above 10,000 feet. As a result, the early surveys in the area were highly irregular, as you can see from the distorted shapes of the sections (the red lines). Blue Tp would be about 4-4.5 miles WNW of Sheep, along Blue Ridge. There is a labeled peak in section 10, near this location, but the elevation does not match. I believe it must have been somewhere along the ridge line near there. Blue Tp may have been a local traverse control station, possibly a blue paint spot on a rock, but is probably faded or eroded away now, if not destroyed. It may have been intended to be only temporary, and was superseded when better points, like Sheep, were later set. All the points in this area would be difficult to reach, even with a valid description. I would say anyone who can find kk2045 deserves 5 gold stars.

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