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.
Modification: 8/25/95 - R. Van Pelt To correct bad TIC -- $RECNO 3233. Methodology: 1. Determined tic location from ITMA by building for NODE and selecting appropriate node to get X -- Y coordinates. 2. In INFO SEL .TIC file and RES $RECNO = 3233 CALCULATE IDTIC = 166306530 CALCULATE XTIC = -575816.210 CALCULATE YTIC = 1781155.129
Modification: 10/4/95 - R. Van Pelt To correct south boundary of KENAI Quadrangle. Methodolgy: 1. Corrected placement of south boundary of KENQ8 in ITMA (see ITMA documentation for details). 2. In AE: set BC ITMA with BE ARC NODE; SPLIT ARC at NODE locations; SELected ARC and DELETEd; set EC ITMA ARC; SELected ARC; PUT QMQA; set EC QMQA ARC; SELected 3 ARCs; CALC $ID = 99; UNSPLIT; CALC $ID = 1; SAVE; QUIT; in ARC BUILD. 3. In INFO ALTERed the QMQA.TIC IDTIC OUTPUT WIDTH to 10 so the IDTIC displays.
Modification: 05/10/96 - D. Mortenson Extented a portion of the Sutwik Island quad to include all islands. Previous versions contained this extention- however- it did not go south quite far enough.
Modification: 6/10/97 - M. Gorham Extended a portion of the Ketchikan quad to include area around Camp Pt. along the Portland Canal.
Modification: 6/17/97 - M. Gorham Straightened boundary between Iliamna and Seldovia quads so it runs along 153 for entire boundary.
Any hardcopies or published datasets utilizing these data sets shall clearly indicate their source. If the user has modified the data in any way they are obligated to describe the types of modifications they have performed. User specifically agrees not to misrepresent these data sets, nor to imply that changes they made were approved by the Alaska Department of Natural Resources.
Some tics were found to be incorrect including missing tics and extraneous tics. These were corrected by projecting the lat/longs from the USGS maps into Albers and adding them to the cover.
Each tic id contains the longitude/latitude for its location in degrees & minutes. For example tic id 157405615 has a longitude of 157 degrees and 40 minutes and a latitude of 56 degrees and 15 minutes. Seconds are not included in tic id but the complete longitude/latitude including seconds was used to position the tics. Negative tic ids were used for the quads of ATTU KISKA and RAT ISLANDS because these islands are located west of 180 degrees longitude.
This coverage includes an outside polygon for the purpose of setting up the library in order to include some areas which fall outside the USGS qmq boundaries. This is in case we ever need to add new tiles to map anything off the coast which would not be covered by USGS quads.