Description: This coverage was generated from an ascii file containing latitude-longitude coordinates for all the corner tics for the USGS protracted 1:63,360 quadrangle sheets covering Alaska. The coverages contains both the 1:63,360 quadrangle boundaries along with the tic locations of the quadrangle corners. Each tic-id is equal to its longitude and latitud in degrees and mintues. Seconds are not included to the tic-id (due to limited number of digits allow for tic-ids), but were used to position the tics on each quad corner. There are negative tic-ids for all the 1:63,360 quads west of the 180 degrees, i.e. Attu, Kiska, and the Rat Islands. The source for the corner coordinates was provided by the Bureau of Land Management (BLM) AEH files. DNR computer programs were used to convert the corner locations into ARC/INFO coverages. The unique tic numbering system, which is tied to each corner, allows for the future development of statewide digital libraries using these boundaries as reference tiles.
Description: This coverage contains the boundaries of the USGS protracted 1:250,000 quadrangle maps covering Alaska. It also includes annotaiton for the quadrangle names in the annotation subclass qmqanno. This coverage was dissolved from another coverage named "itma", which consists of the USGS protracted 1:63,360 quad sheets covering Alaska. The coverage contains tic locations for both the USGS protracted 1:250,000 and 1:63,360 quadrangle corners. Each tic-id is equal to its longitude and latitud in degrees and mintues. Seconds are not included to the tic-id (due to limited number of digits allow for tic-ids), but were used to position the tics on each quad corner. There are negative tic-ids for all the 1:63,360 quads west of the 180 degrees, i.e. Attu, Kiska, and the Rat Islands. The source for the corner coordinates was provided by the Bureau of Land Management (BLM) AEH files. DNR computer programs were used to convert the corner locations into ARC/INFO coverages. The unique tic numbering system, which is tied to each corner, allows for the future development of statewide digital libraries using these boundaries as reference tiles.