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Benchmark/coords Don't Match?

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It appears that you found the azimuth mark for the station, but not the station itself. Azimuth marks are often set a mile or more away from the station, and are used to align surveying equipment. In 2001, the Minnesota Department of Transportation confirmed that the station for PR0977 was destroyed.

 

Do this sound like what you found and where you found it?

THE AZIMUTH MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971,

SET IN THE TOP OF A ROUND CONCRETE MONUMENT FLUSH WITH THE

GROUND. IT IS 98 FEET SOUTHWEST OF THE ROAD INTERSECTION, 75 FEET

WEST OF THE CENTER OF THE ROAD LEADING SOUTH TO THE LAKE, 53 FEET

SOUTH OF THE CENTER OF THE EAST-WEST ROAD, AND 14 FEET NORTHWEST

OF THE NORTHWEST END OF A STONE STRUCTURE SUPPORTING THE SIGN,

OAKWOOD LAKES STATE PARK.

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SoDak Searchers3 -

 

You've found the mark! What you've pictured is an azimuth disk, and the description is for a reset azimuth disk.

 

You should consider reporting this find to the NGS since it is apparently recorded as being destroyed.

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Sorry, BDT, it isn't that simple. The first description does sound like it was an AZ disk used in the main station, but whatever it was it has been replaced. If you read the whole messy history on the NGS data sheet you will find some confusion about what was originally set and then replaced, as well as replacing reference marks, etc.

 

But it is clear that the AZ disk set in 1971 in a round concrete monument was about a mile from PR0797. The photo posted shows an AZ disk in a round concrete post, and as near as I understand the locations it sounds like the right place for the AZ mark, so it is not the station.

 

It cannot be PR0977 which is "SET IN THE TOP OF A SQUARE CONCRETE MONUMENT 16-INCHES BELOW GROUND LEVEL". I would expect that one to be a triangulation disk without any statement to the contrary. Too bad we don't know what evidence MNDT submitted for a destroyed report. It would take a photo of the proper disk and a lot of supporting explanation to get that overruled!

 

I also encourage people to report to NGS when they have useful information, but I recommend they wait until they have a dozen or two finds so that they are more familiar with what to expect and therefore can give more reliable reports, and know how the reports are usually written.

 

I was interested to note PR0976 DESIGNATION - T112N R51W SEC 33 NE COR mentioned in connection with Oakwood Lake. It is one of those very rare cases where the land survey system and the geodetic survey system have point in common. Too bad it doesn't describe the monument at that location. Perhaps someone in the area can check that out as well.

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Bill93 -

 

Yes, I see now. It is quite a mess indeed. Certainly it is that case that a location-adjusted mark can't be a mile off. I believe that the coding "PR0977_MARKER: DZ = AZIMUTH MARK DISK" should be changed to lessen the confusing tale. It is probably a moot point now, as the station is destroyed.

 

SoDak Searchers3 -

 

In light of all this, you should change your log to a note. Keep the picture in the log though. :D I'm recommending a note instead of a Not Found, assuming that you didn't search in vain at the coordinates for PR0977.

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>> a location-adjusted mark can't be a mile off

 

I've never caught a location-ADJUSTED mark off any amount that can be measured with a handheld unit, except for one where somebody entered the coordinates of the wrong point from the USGS list. That made it 0.6 mile wrong. NGS has now fixed the problem by making MH0702 unpublished. That shows that while the data sheet is almost always right, you still need to cross check things.

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SoDak Searchers3,

 

Congrats on find finding PID#PR0977!

 

The only question is which part of the 1971 NGS recovery log is correct. From your pictures I am not sure if the concrete is round or square. In either case case everything fits with the 1971 description of the station mark for PR0977.

 

Quoted from the 1971 recovery report.....

THE STATION MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971, SET IN A SQUARE CONCRETE MONUMENT 16-INCHES BELOW GROUND SURFACE. IT IS NEAR THE CENTER OF THE NORTHWEST-SOUTHEAST RIDGE, 305.5 FEET SOUTHEAST OF A METAL WITNESS POST SET AT THE NORTHWEST END OF THE RIDGE, AND 86.5 FEET NORTH OF A METAL WITNESS POST ON THE SOUTHWEST SLOPE OF THE RIDGE.......... THE AZIMUTH MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971, SET IN A ROUND CONCRETE MONUMENT FLUSH WITH THE GROUND.

 

The Marker Type is " Marker Type: azimuth mark disk"

 

From the description,it is a fair bet that the disk set in the square concrete could be below the disk set in the round concrete. We have found disks set in round concrete posts that are only about 12" high (Total length! They were laying on their sides and not broken off.).

 

When you find a disk that has all the correct markings, then your handheld coordinates for that spot are what counts. You may wish to let the NGS know what you found and where. It is probable that an error was made when the datasheet was first established and no one else has noticed or if they did they didn't bother to notify the NGS.

 

Again, congrats on a good find.

 

John & Shirley

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We need to read the whole NGS data sheet, including its box score, to understand this situation.

 

Whether the found concrete post is round or square makes a lot of difference. The main station was reset in a square post and the 1971 AZ mark in a round post. The picture shows an AZ disk in a round post. Therefore he has not found PR0977.

 

And since the coordinates don't match the data sheet, that is double evidence he hasn't found the main mark. We have no reason to doubt the data sheet ADJUSTED coordinates. His coordinates are 0.9 mile at 223 degrees from PR0977 as found on the Garmin map program. The NGS data sheet lists the az mark as being at 223 03 31.6 which is as close as that program can get. That says he found the AZ mark.

 

There is nothing he needs to report to NGS on this one unless he finds a disk at the coordinates and meeting that description.

 

What part of the 1971 recovery report are you questioning? The only thing that seems strange about the whole deal is why the initial listing said the main station was an AZ mark in 1903. Whatever it was, it has been replaced as shown by subsequent logs.

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PR0977 is for an azimuth mark.

 

"Designation: OAKWOOD LAKE RESET

 

Marker Type: azimuth mark disk

 

Setting: surrounded by a mass of concrete"

 

 

This is what the 1903 description describes. "THE STATION IS MARKED BY A STANDARD AZIMUTH MARK DISK."

 

The 1933 recovery note describes something entirely different. Possibly a station called OAKWOOD LAKE? Unknown at this time. Some how between 1903 & 1933 the station changed from an Azimuth mark to a monel rivet??? Or is that description for an entirely different station mark? Perhaps it describes the station PR0977 is the Azimuth for?

 

The 1965 & 1966 recoveries are "Not Founds", again are they "Not Finding" a different station mark? The Monel rivet?

 

1968 and the mark is declared destroyed.

 

In 1971 The Azimuth Mark is reset. Is it a square concrete post or a round one? Or Both?

 

" THE STATION MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971, SET IN A SQUARE CONCRETE MONUMENT 16-INCHES BELOW GROUND SURFACE."

 

"THE AZIMUTH MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971, SET IN A ROUND CONCRETE MONUMENT FLUSH WITH THE GROUND."

 

Both of the above quotes are from the 1971 recovery! Since the second quote mentions a round concrete post flush with the ground, that is a good indication he found the described mark.

 

If you remove all reference to the Station Mark "BILL" it makes it easier to find the relevant information about OAKWOOD LAKE RESET.

 

There appears to be descriptions of at least three different stations in the recovery reports on the datasheet for this Azimuth Mark. We have found this on several occasions & find it difficult to seperate those descriptions sometimes. With three different mark descriptions in the recovery reports what is the confidence level of the coordinates being correct for the Mark in question? His picture shows the mark as described in the 1971 recovery report - the reset report. I'd say that makes it a valid find for this PID#.

 

He found the correct marker type (according to the NGS datasheet).

It has the correct stampings (according to the NGS datasheet).

It is set in a round concrete post (according to the NGS datasheet recovery note for 1971).

I think the coordinates are for a different mark, possibly "BILL" or "BILL RM?".

 

He made a valid find for OAKWOOD LAKE RESET (the Azimuth mark) as described.

 

John

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You have to read the whole data sheet and reconstruct the history. Here's the story as I see it.

 

In 1903 the C&GS monumented the station called OAKWOOD LAKE using an AZ disk for some reason, perhaps because they had run out of regular disks and didn't want to wait for a new shipment. That is what got coded in the Marker Type field. The description says the station was on a high ridge in the SW part of NE 1/4 of section 33. That agrees with the coordinates and the topo map, and is not down by the lake. They set only one reference mark (type not described), about 1/4 mile (428.913 m) to the SW of the main station (S55 DEG 21 MIN W) and that put it near the SW corner of the NE 1/4 section, which would be about 1/4 mile from the ridge on the topo. The settings for both we can see from the later descriptions was concrete poured into a terra cotta clay tile. Everything is looking like the coordinates are right.

 

In 1933 the C&GS checked on the station, and found the post according to the old description. The post was broken so the AZ disk was gone. The description says "nail" which I interpret as loosly referring to any position mark. They identified the position that the old mark had left and set a rivet in that position in the same post. The original reference mark was still there.

 

In 1965 the USGS looked for OAKWOOD LAKE and did not find it. In 1966 the C&GS couldn't find it.

 

In 1968 the USGS really wanted a station around there and looked again. Local people told them that the ridge had been used to supply dirt for road building and since they couldn't find the mark they proceeded to set PR0978 designation BILL on the same ridge, as it turns out just 2.656 meters (8.7 ft) NW (302 50') of the missing OAKWOOD LAKE. The topo shows an x about there, probably for BILL.

 

In 1971 the NGS re-checked this area. They found BILL and its RM's. It is only a second order station and OAKWOOD LAKE was first order, so they wanted to find the better one. They measured from BILL and dug and found the 1933 rivet in concrete post at OAKWOOD LAKE. They couldn't find the RM for OAKWOOD LAKE so asked around and were told that it had been plowed out. Wanting the 1903 position, not the 1933 rivet, they carefully referenced the rivet and then dug out its post to see if an underground mark was there. They did not find an underground mark, which althoug expected had never been specifically noted in the 1903 log.

 

They then put in a new monument, carefully positioned from the references they had made off the rivet before they dug its post out. It was a STANDARD DISK STAMPED OAKWOOD LAKE

1903 1971, SET IN A SQUARE CONCRETE MONUMENT 16-INCHES BELOW GROUND SURFACE. This is what is defined as PR0977 OAKWOOD LAKE RESET. They redescribed BILL on the OAKWOOD LAKE RESET data sheet because they re-used BILL and its reference marks to reference the new disk.

 

At this same time they set an azimuth mark STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971, SET IN A ROUND CONCRETE MONUMENT FLUSH WITH THE GROUND. Since they didn't note to the contrary, standard would usually mean one marked AZIMUTH. Its location as described was a bigger part of a mile away, which was a common practice in the 1960's, and it was SW bearing 223 03 31.6.

 

In 1974 the NGS looked into it again. They talked to the farmer who was on the land in the 1950's and he said the plowed-out post had come from the location of the main station, not the reference mark. So that means the 1971 party had really found the underground mark and mistook it for the surface mark. I'm not sure I'm convinced, but it doesn't matter because they didn't change anything in 1974 except setting an additional RM3.

 

In 2001 the MNDT reported OAKWOOD LAKE RESET as destroyed. I wish we knew what they found.

 

In 2006 a geocacher found the AZ disk as described near the lake, in a round concrete post as described, and an AZ disk as described in 1971, about 0.9 file SW from the ridge that PR0977 OAKWOOD LAKE RESET was on. He did not find anything on a ridge, or near the coordinates, or in a square concrete post, nor a standard triangulation disk, so there are 4 reasons he did not find PR0977.

 

The whole story fits together, and seems entirely consistent with the logs.

Edited by Bill93

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So the question then becomes - What did he find?

 

He finds the correct type of mark with the correct type of setting and correct stamping as described in the 1971 recovery log for PID# PR0977, but it is something other than what is described? What then?

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I think one of our main points of disagreement is what kind of disk was set at the main station in 1971. The original disk in 1903 was noted as an azimuth disk; they made the notation because it was not the standard thing to use in that position. In 1971 they said "standard disk" and that would have meant a triangulation station disk at PR0977 since it is the main triangulation station on the ridge. The azimuth mark they set in 1971 would have been an azimuth disk since that was standard for the purpose. If that were the only evidence, I would agree that it was debatable. But that is just one thing in a long list.

 

He finds the correct type of disk for the Azimuth mark that was set in 1971, with the correct type of setting (round post) described for the 1971 azimuth mark, and correct stamping as described in the 1971 log for the azimuth mark, at a location that fits where the 1971 description says they set an azimuth mark almost a mile from the main station. It is the azimuth mark that was set in 1971 to go with PID# PR0977.

 

He did not find the correct type of disk for a main triangulation station reset in 1971 as PR0977, did not find it in a square post like PR0977, did not find it on a ridge in the middle of section 33 where PR0977 was, and did not find it at the coordinates of PR0977.

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So the question then becomes - What did he find?

 

 

CO9329 OAKWOOD LAKE AZ MK 2

 

"PR0977'THE AZIMUTH MARK IS A STANDARD DISK STAMPED OAKWOOD LAKE 1903 1971,

PR0977'SET IN THE TOP OF A ROUND CONCRETE MONUMENT FLUSH WITH THE

PR0977'GROUND. IT IS 98 FEET SOUTHWEST OF THE ROAD INTERSECTION, 75 FEET

PR0977'WEST OF THE CENTER OF THE ROAD LEADING SOUTH TO THE LAKE, 53 FEET

PR0977'SOUTH OF THE CENTER OF THE EAST-WEST ROAD, AND 14 FEET NORTHWEST

PR0977'OF THE NORTHWEST END OF A STONE STRUCTURE SUPPORTING THE SIGN,

PR0977'OAKWOOD LAKES STATE PARK."

 

That is what was found.

 

Check it out at the NGS Datasheet for PR0977

 

The descriptions for the Azimuth Mark in both 1971 and 1974 match the photos and description in SoDak Searchers3 log. It certainly is not the station mark, which, when reset, was not an azimuth disk but, instead, a standard disk. And the disk he found is in a round concrete post flush with the ground, matching the 1971 and 1974 Azimuth Mark descriptions as well. The photos make it appear to be the correct distances from the road.

Edited by GH55

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Hey you all have been a great help and I did log this as a find because all signs lead me to believe it is the right marker. But the bottom line on the NGS page says this:

 

PR0977'RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 2001 (DB)

PR0977'THIS STATION WAS VERIFIED DESTROYED BY MNDT.

 

Its been verified as destroyed when actually it wasn't. So where do i go from here with the info? :laughing::laughing:

 

Lucky find huh? :laughing: LOL!!

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I know we were long-winded, but the consensus of several posters here is that you have not found PR0977, so you have not shown the "destroyed" report to be in error.

 

They reported the main marker on the ridge which is PR0977 as destroyed. The mark which defines the position on the data sheet often has reference and azimuth marks to assist with its location and its use. You found one of those instead. There is no evidence of an error on the data sheet unless you can find the marker as described on the ridge at the coordinates.

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SoDak Searchers3 -

 

I agree with Bill93. You have found the azimuth mark instead. The finding of the azimuth mark of PR0977 is not a find of PR0977. I recommend you change your log type from "Found" to "Write note".

Edited by Black Dog Trackers

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OK, what I meant to say earlier:

 

There are several reasons to believe that station PR0977 "OAKWOOD LAKE RESET" was not found:

 

(1) The station was recovered (found) by the NGS in 1974 at the correct coordinates and rechecked at that time.

 

(2) the station mark was set in a square concrete monument - the disk that was found is set in a round monument.

 

(3) the station mark was set 16 inches below the ground surface - the disk that was found was flush with the ground.

 

(4) the station is described as being 0.35 miles south of an east-west graded road on a ridge in a cultivated field - the photos show the disk you found near a road and not on a ridge.

 

(5) the station "Oakwood Lake Reset" is described (in the box score for PR0978 "BILL") as being 2.656 meters (8 ft 9 in) at 122 deg 50 min from PR0978 "BILL". That distance was checked by the NGS in 1974. The coordinates for the two stations indicate they are only a few feet apart.

 

PR0978 BILL NAD 83(1996)- 44 27 53.86665(N) 096 57 19.96752(W) ADJUSTED

 

PR0977 OAKWOOD LAKE RESET NAD 83(1996)- 44 27 53.82001(N) 096 57 19.86656(W) ADJUSTED

 

It is extremely unlikely that NGS would get the coordinates wrong on two marks on several separate occasions.

 

(6) The datasheet indicates that a reset was made in 1971 and at that time, a standard disk was used - the disk that was found is an Azimuth Mark disk.

 

(7) the station was described in 1971 and in 1974 as being 3/4 mile north-northeast of the north end of Oakwood Lake. A check on Topozone shows the published coordinates as being on a ridge, at an elevation between 1750 and 1760 feet, about 3/4 mile northeast of Lake Oakwood, about 0.35 miles south of an east-west road. The east west road has a curve, and a westward continuation just as in the "go-to" description for the AZ mark. Therefore, the published coordinates and the published description of the location for the station match closely.

 

There are several reasons to believe that you found CO9329 OAKWOOD LAKE AZ MK 2:

 

(1) the disk you found is in a round concrete monument, the AZ Mark is described as being set in a round concrete monument.

 

(2) the disk you found is flush with the ground - the AZ Mark is described as being set flush with the ground.

 

(3) from the photos it appears to be the correct distances from the road for the AZ Mark - 98 feet southwest of the center of a road intersection, 75 feet west of the center of the east-west road, and 14 feet northwest of the northwest end of a stone structure supporting the sign "Oakwood Lakes State Park."

 

(4) You describe the disk you found as being "almost a mile off from the coords." - The "go to" description for the AZ mark describes it as being, from the field entrance of the road that is 0.35 miles north of the station mark, west about 0.65 miles and south about 1.0 miles. From plane geometry, that would put the AZ mark roughly 0.80 to 0.85 mile SW of the station mark coordinates.

 

(5) the disk you found is an Azimuth Mark disk stamped OAKWOOD LAKES 1903 1971 - the datasheet indicates an azimuth mark was set in 1971 at a location consistent with the description of where the disk was found.

 

(Did I miss anything?)

 

Based on that evidence, it is as certain as one can be that the azimuth mark "OAKWOOD LAKE AZ MK 2" was found and PR0977 "OAKWOOD LAKE RESET" was not found.

Edited by GH55

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... all signs lead me to believe it is the right marker.

 

The evidence seems overwhelmingly to indicate that it is not.

 

Just which signs would lead you to believe it is the right marker?

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OK so you all have your opinions and have shared with me what you believe this marker is. You still really haven't answered my questions. HOW do you figure out from benchmarks what they are when it doesn't actually say PID on it or give a station name. And other than being a rocket scientist or a real live survey person how the heck does one understand these data sheets? But I did go back and read the data sheet (for the 10th time) and at the end of the description is describes this marker. And on PR0977 it says Azimuth Marker. I now understand that the datasheet originally started out as describing a station but then went into describing this same exact marker that i found. So I found this marker but can't post it anywhere? Because this is just a benchmark which points to the station?

I love looking for these benchmarks because its a real challenge but i already have a whole handful of them i don't know what to do with or where to post them because no one has really given me an answer yet. How on earth did you find CO9329 OAKWOOD LAKE AZ MK 2, GH55?? And yes your right. That fits the description well. But even looking under the station name and doing a datasheet search for it on the NGS website i still didn't come up with that. And what on that marker indicates to you what to search for that you came up with that? :lol::wub::wub:

I have markers that say geodetic survey on them and i have one that says geological survey on it. Whats the difference? Do I post them as finds on benchmarks on gc.com? I can't find the CO9329 OAKWOOD LAKE AZ MK 2 on gc.com to post it. Thats the question that newbies like me need to know when coming to this site. I thought thats what this forum was for?

Anyways, thanks for all the help. Ahead of time. :P:):D

Laurie

Edited by SoDak Searchers3

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HOW do you figure out from benchmarks what they are when it doesn't actually said PID on it or give a station name.
It would be much easier if they'd put the PID on them! The answer to this question is experience. It takes a several months of benchmark hunting to get the experience you need for 90% of the marks. The other 10% take more experience to figure out.
And other than being a rocket scientist or a real live survey person how the heck does one understand these data sheets?
There's also experience needed to understand the survey-speak in datasheets. :lol:

 

How on earth did you find CO9329 OAKWOOD LAKE AZ MK 2, GH55??
This mark is only listed in the NGS datasheet format in the box score for PR0977. You see the NGS datasheet format by either clicking on

"view original datasheet" on the geocaching sheet or by going to the NGS website to get its datasheet for the PID. CO9329 is not a regular PID that you can look up directly at the NGS site. It is shown in the 'box score' for PR0977 only.

 

I have markers that say geodetic survey on them and i have one that says geological survey on it. Whats the difference?
The difference is which agency set the disk. There are different agencies' disks that say "geodetic survey" on them. Some are state agencies, some are county agencies, some are national agencies. The USGS disks are set by the U.S. Geological Survey. The USC&GS disks were set by the U.S. Coast and Geodetic Survey, a predecessor of the National Geodetic Survey. There are lots and lots of different agencies' disks represented in the NGS database. We even have a virtual collection of them! Check out the collection!

 

You can post any benchmark agencies' benchmark on gc.com IF the benchmark is included in the gc.com copy (circa 2000) of the NGS database.

 

Posting a "Write Note" on PR0977 with a picture of OAKWOOD LAKE AZ MK 2 is a proper thing to do. It doesn't constitute a find of PR0977, but you can post a note for PR0977 since OAKWOOD LAKE AZ MK 2 is its azimuth mark.

 

Don't worry a lot about PR0977. It is a very vague and complicated situation, and way beyond the typical in that regard. It's bad luck to run into this one as you start benchmark hunting, but don't let that get you down. We're here to help, too. :wub:

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Under normal circumstances, you simply need to be able to recognize the difference between a reference mark, an azimuth mark, and the station mark. There are relatively few reference marks that have their own distinct datasheets -- around my area, less than half, maybe less than 25% of reference marks have their own datasheets. It much, much rarer that an aziumth mark has its own distinct datasheet.

 

Therefore, unless a datasheet explicitly states that it describes a reference mark or an azimuth mark, you should assume that the data sheet describes the primary marker for the station. You can generally look at the "designation" part of the datasheet to see if RM or AZ is in the designation; if it is, then the datasheet is probably describing a reference or azimuth mark.

 

When I say "describes", I mean which mark is described by the datasheet's coordinates and/or the elevation, which is what the datasheet is all about. Yes, the textual description often talks about reference marks and azimuth marks, but they are only incidental to the primary subject of the datasheet, which is the mark having the coordinates and/or elevation stated at the top of the datasheet. If you want to log a "find" you have to find the mark that is descibed by the datasheet's coordinates and/or elevation.

 

You also want to look carefully at what is embossed and stamped on the disk. The markings should match the "STAMPING" on the datasheet.

 

Also, a reference mark or azimuth mark usually has an arrow embossed in the mark, and the arrow points toward the primary station. If you find a mark that has such an arrow, you can be 95% sure that you have found a reference mark or azimuth mark. Sometimes the surveyors used a spare reference disk or azimuth disk for the primary station, but they didn't do it very often, and if they did, they may have noted that fact in the description, too.

 

In your case, there where three immediate strikes against your find: first and foremost the disk you found was at the wrong location, the disk you found had an arrow on it pointing to the right location (hey, where did that image go? Did I imagine that?), and a reputable agency had made an explicit note that the station had been destroyed. The final nail in the coffin was that the mark you found was a perfect match to what was described as the azimuth mark for PR0977. It was also at the location where PR0977's azimuth mark should be. Hence the conclusion: you found the azimuth mark for PR0977, but not PR0977 itself.

 

There were two things about PR0977 which made it unusually difficult to sort out: 1) the datasheet indicated that PR0977 was one of the rare cases where an azimuth disk was used to mark the station, and 2) PR0977 has had an unusually complicated history.

 

As far as hunting marks goes, the best technique is to first find the datasheets that describe marks in your area, and use the datasheets to find the marks. Most people who stumble across a mark and then go searching for a matching datasheet are going to be disappointed, because maybe less than 1% of all the survey markers out there will have a datasheet in the NGS database.

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Sorry to take so long to reply, but my computer was down for a few days waiting on a new mother board.

 

How on earth did you find CO9329 OAKWOOD LAKE AZ MK 2, GH55??

 

Anyways, thanks for all the help. Ahead of time.

Laurie

 

If you look (again) at the NGS Datasheet, you will find a box that looks something like this that lists reference objects for this mark: PR0977|---------------------------------------------------------------------|

PR0977| PID Reference Object Distance Geod. Az | dddmmss.s |

PR0977| PR0969 BROOKINGS SD ST COLL CAMPANILE APPROX.21.3 KM 1410704.3 |

PR0977| PR0973 BROOKINGS MUNICIPAL TANK APPROX.22.0 KM 1420213.6 |

PR0977| CO7834 BILL RM 2 18437 |

PR0977| CO9331 OAKWOOD LAKE RM 3 27.274 METERS 19414 |

PR0977| CO9329 OAKWOOD LAKE AZ MK 2 2230331.6 |

PR0977| PR0861 ARLINGTON MUNICIPAL TANK APPROX.18.2 KM 2313054.4 |

PR0977| CO9330 OAKWOOD LAKE RM 23521 |

PR0977| PR0978 BILL 2.656 METERS 30250 |

PR0977| CO7833 BILL RM 1 32451 |

PR0977|---------------------------------------------------------------------|

 

Notice that there are some reference objects listed with similar PID's, such as PR0861 ARLINGTON MUNICIPAL TANK that have their own PID and datasheet. Those are also reportable at Geocaching if they were in the database that was loaded there. A search for nearby marks should turn them up.

 

Other reference objects that are not surveyed and worked up to a degree that they are included in the NGS database, but are nonetheless used as reference objects from the station are given an identifier that looks something like a PID in that it has two letters followed by 4 digits. This is not a PID, but just something to identify the object in the records. The Azimuth mark is one of those objects, as are the reference marks. There is no provision for reporting these other reference objects except to note the results of the search for them in the notes to the report of the main station.

 

I hope this helps. One of the great things about this pursuit is that there is so much to learn!

 

GH

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SoDak,

I think one of your questions left unanswered is: What do I do with all of these disks I've run across that I can't log at Geocaching or the NGS?

This is a question that often comes up, because people run across all sorts of disks that are not in the database. To quote the Frequently Asked Questions:

 

2) We found a disk not listed on GC.com, now what?

 

Please check here - FAQ - for the first answer. If you do not find what you are looking for please start a new thread in the forums with as much detail about your benchmark as possible (the stamping on the disk, the location, and even a picture.) and let us know what type of info you're looking for. There are so many different agencies that set benchmarks that Geocaching couldn't afford the servers needed to house all those databases, so they chose to use the database of the most prestigious (Boy, will I hear about this!) agency for our benefit. We use the NGS database, but it is several years old now and there are newer benchmarks that can be found on their site. More on searching their site later.

 

If you find a benchmark that is NOT listed here you may still be able to log it on GC.com by going to Waymarking.com - Waymarking.com - and checking their list. Waymarking is just getting started so you may be the first to create a Waymark for your benchmark.

 

In the last week I've run across three not in the database, a DOI NPS disk, a private surveyor's disk (new agency noone's seen before) set along a state road and a AMAFCA disk (also a new agency). It happens. There's 3,000 City of Albuquerque disks here in Albuquerque that are in their own database, but not in the NGS list.

Edited by BuckBrooke

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