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Everything posted by tosborn

  1. After going down the list of highest points in Monroe (overpasses, mounds in gravel yards, and a backstop for a rifle range), I believe the highest natural area is the plateau of sorts that includes tri-station Sicard (CQ2664, N32.53019°, W092.01085°, NAD83) at an elevation of about 95 feet. The tri-station is actually just outside the city boundary. So inside the boundary look at N32.53047°, W092.01431° or somewhere nearby. NGS lists tri-station Sicard as destroyed, but the circumstances seem odd. On Jan 1, 2011 GEOCAC recovered the station disk and two surviving reference marks but not the azimuth mark. On the very next day, NGS reported the station as destroyed with no explanation. Might be worth a trip to see what is or isn't there. For West Monroe, it looks like the highest natural point within the city boundary (US Census) is at or near N32.50650°, W092.19290°. The topo map shows three enclosed 150 foot elevation contours there. However, the northerly one is at the exit and entry ramps of Interstate 20 and so may have been affected by construction.
  2. Travis: I brought the boundaries of West Monroe, and Monroe into my GIS program and overlaid them on USGS elevation contour data and National Elevation Data. It appears that the high points in both cities are overpass embankments. For West Monroe the high point is at 32.51138, -92.19194 (NAD83 Lat, Long) at an elevation of nearly 157 feet. There is an NGS Datasheet for a survey disk in the overpass roadway. It's PID is CQ2678. For Monroe the high point is at 32.5181, -92.07986 (NAD83 Lat, Long) at an elevation of nearly 103 feet. The nearest PID for this point (CQ3431) is .3 miles away. Hope that's what you wanted.
  3. That does seem unusual. Maybe it wasn't occupied (as in setting up a theodolite on the station from which to sight other objects) since there is no box score.
  4. Not sure I understand what you are saying. But at least a year ago I reported that Deb at NGS said she would prefer to receive no reports on intersection stations...no recoveries and no destroyed reports.
  5. Dave: What do you know about the history of the mini obelisk? It appears that it's PID is HV1841 and it was first recovered by NGS in 1971. The monumented date is unknown by the Department of Defense. Does this go back to the original construction of the Washington Monument? If it is more recent it seems like it would have been a lot easier to just drive a rod rather than create a 12 foot tall buried version obelisk. Enjoyed the podcast. Tim Osborn
  6. I think this reads such that "North" and "East" are relative directions with respect to the highway. So, this is how I would interpret it: at the point of intersection between the highway and the railroad, proceed 74 feet perpendicular to the direction of the highway in a Northerly direction (based on Topo maps that would be a true azimuth of about 348.3 degrees). Then, from that point go parallel to the highway 117 feet in an Easterly direction. That puts you almost exactly on top of the BM X on the topo map. You'll cross over the tracks on that second leg.
  7. Yes, put it on your website and let us know the url.
  8. Looks like it was PID EJ1729, recovered on 20110416 by DOR. Found by doing a datasheet search via Load Date (June).
  9. The explanation on Wikipedia seems to be the most repeated version. But a while back I came across this link which offers some alternative theories.
  10. The General Land Office Public Land Survey System (GLO PLSS) was all about marking corners so that the public lands could be homesteaded or sold into private property. Entrymen took possession based upon the PLSS corners. If the landowner you referred to owned the 40 acre quarter-quarter immediately to the southwest of this corner, then it surely was his NE property corner. If he only owned the next quarter-quarter to west, then he was probably mistaken.
  11. No. The Datasheet folder contains the most recent monthly State Archive files in textual format. The Archive folder contains the archived Archive files....in other words, last month's textual format Archive files. That's why I said the word "archive" has two meanings.....1) a statewide snapshot and 2) last month's files.
  12. That's correct. Important data items for benchmarking that are not in the shapefiles are monumentation type (e.g. benchmark, triangulation station, tower, etc), stamping, box scores, setting, and "to reach" info. The following fields are what the shapefiles include: DATA_DATE - date the archive was prepared DATA_SRCE - URL of the datasheet DEC_LONG - decimal longitude DEC_LAT - decimal latitude PID NAME STATE COUNTY QUAD - USGS quadrangle containing mark LATITUDE - degrees, minutes and seconds LONGITUDE - ditto POS_DATUM - NAD83 DATUM_TAG POS_SRCE - scaled, adjusted, HH ELEVATION ELEV_DATUM ELEV_SRCE ELLIP_HT ELLIP_SRCE POS_ORDER POS_CHECK ELEV_ORDER ELEV_CLASS ELEV_CHECK DIST_RATE ELLP_ORDER ELLP_CLASS FIRST_RECV - first recovery date LAST_RECV - last recovery date LAST_COND - good, not found, etc LAST_RECBY - agency for last recovery SAT_USE - satellite visibility SAT_DATE STABILITY
  13. The NGS database is constantly changing....new recoveries, new marks, marks classified as destroyed, etc. Once a month on a particular day for each State, NGS takes a snapshot of all non-destroyed PIDs. They call this an archive since, on the very next day, one or more datasheets may be different due to new recoveries, new marks, etc. The archive can be either in textual datasheet format (Datasheets folder), or they can be in shapefile format (Shapefiles folder). After a month, they create new archive files for the State, and save the previous month's textual datasheet archive in the ARCHIVE folder. The previous month's shapefile archive is saved in an Archive folder under the Shapefiles folder. So there are really two meanings of archive involved. But archive doesn't mean destroyed or inactive.
  14. In checking the NGS database this evening I see a November 20, 2010 GEOCAC "MARK NOT FOUND" report for FAWN by FSC. That's pretty recent. Are you perhaps FSC? If not then its too soon for another report unless you have different recovery results.
  15. http://www.mappingsupport.com/p/gmap4.php?z=15&t=t2&icon=ch&ll=36.15438,-94.23657 Replace the coordinates at the end of the above URL with your hand-held coordinates (lat,lon) and view in your browser. A crosshair icon will be placed on the map at the location of your coordinates.
  16. Dave: Here are 13 PIDs for Arkansas. They should constitute all of the adjusted marks in Arkansas with an incorrect County Name. I didn't see any point in checking scaled marks(coordinate accuracy) or intersection stations(relevance). I have checked each of these 13 against Bureau of the Census Arkansas county boundaries for 2010 and USGS 1:24,000 topo maps. PID WrongCounty CorrectCounty DG4779 CHICOT DESHA DK2001 DESHA CHICOT DK2009 DESHA DREW DL1575 MILLER HEMPSTEAD EH0993 LEE PHILLIPS EH2912 MONROE PHILLIPS EH3062 PRAIRIE LONOKE EH3076 PRAIRIE LONOKE EH3117 LEE ST FRANCIS EJ1878 PERRY PULASKI EJ1911 SALINE GARLAND EK0817 SCOTT POLK FF1965 MISSISSIPPI CRITTENDEN Tim
  17. Deb recently clarified that she would prefer to receive no reports of any kind concerning intersection stations such as KS1902. If you found the displaced disk from KS1126 then you could send a photo to Deb to have it classified as destroyed, otherwise the convention is to report it as not found.
  18. I converted the coordinates from State Plane NAD27 to Lat/Long NAD83 using Corpscon.
  19. It appears that the coordinates are Mass Mainland State Plane coordinates, NAD27 US feet. If so, they would translate to 42.347792473 degrees latitude by -73.119747542 degrees longitude (NAD83). This is a point near the intersection of Schulze Road and the Pittsfield Road. Schulze Road would be the "Y ROAD EAST." Elevation of 529 meters looks correct for this location on topo map. However this location is 2.25 miles Northwest of Becket...not 1.7 miles Northeast as description states.
  20. Same thing as "beating the bounds." (see this wikipedia link)
  21. In late August we had a discussion (link) about reporting destroyed intersection stations (e.g. water towers, church steeples, etc) to NGS. It has been stated by some here that while NGS (Deb Brown) no longer wishes to receive positive recovery reports on intersection stations, destroyed interesection stations should continue to be reported to NGS so that they can be removed "from the active database to reduce clutter." Shortly after that discussion I emailed Deb Brown the following: Yesterday I received the following response from Deb: So I would humbly suggest that we respect Deb's wishes and refrain from submitting info of any sort to NGS concerning intersection stations. Tim
  22. There was this thread from May 2009 about an existing Bilby tower in Louisiana: http://forums.Groundspeak.com/GC/index.php?showtopic=221772
  23. tosborn


    A spot elevation is a label on a topographic map that measures the vertical position of a point at less than third order accuracy. There is usually at least one spot elevation shown per square mile. You may see them at prominent tops, saddles, or depressions, intersection of trails and road, sharp turns in linear features, boundary marks, PLSS corners etc. The T indicates that this spot elevation was determined using photogrammetric methods...meaning it was not determined in the field but from aerial photography.
  24. tosborn


    Its an unchecked photogrammetric spot elevation.
  25. Be careful with respect to using the metal detector if the area in question is within the bounds of the National Historic site. The National Park Service prohibits the use of metal detectors and will likely confiscate it unless you get their prior approval.
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