Loading ...
Sorry, an error occurred while loading the content.

GEOSTATS: Land-grid to map projection conversions

Expand Messages
  • Larry N. Smith
    I am interested in finding out what are the various methods people use in the conversion of locational data from land-survey grids to map projection units. In
    Message 1 of 1 , Aug 11, 1997
    • 0 Attachment
      I am interested in finding out what are the
      various methods people use in the conversion
      of locational data from land-survey grids to
      map projection units.

      In our shop we use a program modified from one
      written at the Montana USGS office (but never
      published) that calculates latitude and longitude
      for a point in the US General Land Office grid
      system (township-range-section), based on
      digitized corners of townships or sections. The
      program can handle a precision of up to 1/1024 of a
      section (approximately a square mile), although
      the way it handles irregularly distorted sections
      is not too elegant.

      In order to improve locational accuracy, we are
      reformating Arc/Info basemap coverages of sections,
      whereas we had used the township corners previously.
      The reformatting of the basemap must essentially
      be done by hand to extract "sigificant" corners in
      the grid.

      I am wondering what others do to convert large
      quantities of data points when they are supplied
      with locational data like the township-range-section
      format.

      Except for some references to Kansas Geological
      Survey programs from the 1960's, where the land-
      grid is much more regular than in is in the western
      U.S., I am unaware of other programs that are used
      in North America or elsewhere.

      thanks

      Larry

      _____________________________________________________________
      Dr. Larry N. Smith 1300 West Park St.
      Montana Bureau of Butte, MT 59701-8997
      Mines and Geology (406) 496-4379 (v)
      Montana Tech of the (406) 496-4451 (fax)
      University of Montana larry@...
      http://mbmgsun.mtech.edu
      _______________________________________________________________
      --
      *To post a message to the list, send it to ai-geostats@....
      *As a general service to list users, please remember to post a summary
      of any useful responses to your questions.
      *To unsubscribe, send email to majordomo@... with no subject and
      "unsubscribe ai-geostats" in the message body.
      DO NOT SEND Subscribe/Unsubscribe requests to the list!
    Your message has been successfully submitted and would be delivered to recipients shortly.