View Full Version : Benchmarks on top of Pinnacle Mt

07-17-2004, 10:40 PM
I tried to find the BM disk WAU, and the Maumelle reset Triangulation station. I thought it was strange that no one had logged these since I know there have been a few cachers who have climbed the mt.

I searched for WAU (Somewhere close to the park entrance on the west side) for about 15 minutes with no luck. I thought for sure I would score with the maumelle reset. After a gruelling hour long hike in the 90* heat, I finally made it to the summit w/ both Squirrel21309 and Lil angel in tow.

I looked for the obvious disks but no such luck, then I started noticing some irregularities in the rocks. You tell me if I am right in thinking these are the locations that at one time held the triangulation station, and BM diks. See Log
:arrow: http://www.geocaching.com/mark/log.aspx?LUID=701f1bfc-040d-4fdb-9292-1a4552b42b93

After reading the official notes when I returned I noticed that they've had to replace these BM almost ever time they recovered them. My theory is that some tourist thought that these disks woukd make a nice souvenier from the mt. Just a theory based on the high muggle traffic in the area.

If the marks have been plundered, how do we go about getting them replaced? Aby thoughts?

07-18-2004, 01:18 PM
From your photo's it appears you found the spot where the disc was,I can not tell for + from a phot but it appears to be evident on the rocks that the mark has been removed.
You will find this in high traffic areas(muggles).

You can report your find to the NGS as destroyed,or poor more precisely because you did not find the disc,to say it has been destroyed,(kinda confusing but).

FROM http://www.geocaching.com/mark/

What do I do when I find a benchmark? You simply log your find on the site. You do not take them, even when they appear to have been damaged. These markers are public property, are actively used in surveying, and are protected by law. In the unlikely event that you discover a marker lying loose on the ground, the best thing is to leave it where you found it. For further information you can look here.

How do I log a benchmark?
On the benchmark's page, click on "Log this benchmark" at the top right corner of its page to log your find. If you have a digital camera, we ask that you take a picture of the mark, and one or two pictures of the area around the mark. Even if you don't have a digital camera, just log your find for others to read. After you have successfully logged your find, you can click on "[upload images]" to upload your pictures. When uploading images, you can put the station's Designation (name, not PID) as well as its State and location in the "Name:" field - it makes the benchmark gallery more interesting.

Some listings describe things like radio towers, church steeples and smokestacks. How do I log them?
Unless (in very unusual cases) the description says that there is a benchmark disk, surveying nail, or other small object that can't be seen from the ground, the top of the tower, steeple, or smokestack is the station. Do not climb it. Simply log your find, and if you have a digital camera, take the structure's picture from the ground. These kinds of "large object" station markers, known as intersection stations because of the way their coordinates are calculated, are usually landmarks higher in the air than any surrounding objects, allowing them to be seen from many miles away in several directions, which makes them valuable as points of reference. By observing one or more such points through a telescope, surveyors can determine positions on the surface of the Earth through the use of trigonometry.

What do the choices "Found it!", "Couldn't find it!", "Destroyed", and "Post a Note" mean?
You can log "Found it!" if you see the marker and know that it is the correct marker. If the marker is a survey disk, you must read the disk. The designation (its name) stamped on it must match the Designation in the description. Reading the disk is necessary because another disk could have been set within a few feet of the one you're looking for. If the station has reference marker disks, they don't count as the find; you must find the station disk itself.

If you searched carefully, and could not find the marker, you should log "Couldn't find it!" so that other benchmark hunters will know that the mark is going to be difficult or impossible to find. There is nothing wrong with doing a good job of looking and not finding the marker, since many of them are actually gone and many others are buried under dirt, asphalt, concrete, etc.

"Destroyed" means that you know that the benchmark cannot be in its original location because the structure it was on is gone. Don't log as destroyed unless you are absolutely sure. If there is any doubt at all, it's best to refrain from using this option and let someone else have a chance at finding it. Remember, you can always seek advice from more experienced hunters by posting a message, which may enable you to increase your chances of success!

"Post a Note" is good for letting other benchmark hunters know about some special problem they may encounter looking for the benchmark, for an update on the benchmark's status, etc.

What are reference marks and azimuth marks for and how do I log them?
Reference marks are for helping to keep the location of triangulation stations from being lost. The triangulation station's description has accurate azimuth and horizontal (not slope) distance to each of its reference marks so that it can be re-set from them if necessary. An azimuth mark, together with its associated triangulation station, provides an accurate azimuth (like a compass direction) that is based on true North rather than magnetic North. This azimuth is used to orient local traverse surveys. The only reference marks and azimuth marks that can be logged on their own are those that have their own PID. If you're looking for a triangulation station and only find its reference mark or azimuth mark, you can't properly claim "Found it" (unless the reference mark or azimuth mark has its own unique PID, in which case you'd log it under that PID), but you could log it as "Couldn't find it" and even upload the picture of the reference mark.

I found a benchmark, but it isn't in your database. Why?
The NGS is not the only organization that creates and uses benchmarks and other types of control markers. For example, the US Army Corps of Engineers (USACE) places survey markers at their dams, dikes, levees, flood control systems and other structures. The Bureau of Land Management (BLM) and other federal agencies, along with your county surveyor and private surveyors and engineers place markers that often appear very similar to geodetic markers, to reference land survey corners as part of the public land survey system. Your local highway department also may have set markers along highways, at major bridges and overpasses. Many markers have also been set in recent years by utility companies, telecom companies, and others engaged in laying pipe or cable over long distances, to mark their underground lines. In most cases, the information stamped on the disk will tell you, or at least give you a clue, about its purpose. Remember, all these markers are highly important, both to businesses and to individual citizens such as your neighbors, so please treat them with respect, while enjoying the thrill of the hunt. We'll try to find other databases and add them to the site as well. If you have access to one of these databases and would like to submit it to Groundspeak, contact us.

07-19-2004, 01:32 PM
Wow! Geo you sure know a lot about survey bench marks. Are you an ex-engineer or land surveyor? Thanks for sharing that information.

07-19-2004, 01:51 PM
I am a disabled Measurement Tech.
I am currently a volunteer with the BLM USGS as the local mapper here in SW Missouri,for the National Map Program.
I am a History Buff and have been all over the US and Mexico.
I have been working on the PLSS here for 10 years or so.
I guess you could say I was the first one before selective availability was turned off to be working with some NASA programs in the Field of GPS and Measurements of the Earth.
I was talking with the Space Shuttle Commader, Kevin Kreigle and crew on the computer during the SRTM Mission (SPACE RADAR TOPOGRAPHY MAPPING).


Of course all the measurements of the Louisiana Purchase and the PLSS began right there in Arkansas.
www.lapurchase.org (http://www.lapurchase.org)

Which is also a Benchmark.

07-19-2004, 07:25 PM
As a former resident of southwest Little Rock I have always heard that Baseline Road was laid out on the Base Line that was surveyed westward from that beginning point mentioned in GEO's post. Just a little bit of useless (for most of us) trivia.

07-19-2004, 10:18 PM
You are correct with that trivia bit.
I also have 2 caches on that base line surveyed by Joseph C. Brown.
and 2 on the North line surveyed by Prospect K. Robbins.