OVERVIEW

MassGIS has adopted the Massachusetts State Plane Coordinate System (SPC) as its standard coordinate reference system, using the Mainland zone throughout the state. MassGIS has generated an SPC point layer called GRID10K. Using a grid with 10,000 feet on a side, the points were derived from the grid intersections. This coverage can be plotted on a map as coordinate reference. The plotting of coordinates on a map enables that map to be used as a compilation manuscript for further data automation. The points can be used as 'TICS' to register the plot/manuscript on the digitizing table. This is of great utility to any project planning to digitize information that needs to be compiled onto GIS plots because it insures that the new data will register to the other datalayers in the MassGIS system. The datalayer is stored as a single coverage in the NE library named GRID10K and in ArcSDE as GRID10K_PT.

MassGIS staff produced GRID10K using the ARC/INFO command GENERATE. The grid starts at the origin of the Massachusetts SPC Mainland Zone and has a grid block size of 10,000 feet on a side. MassGIS then made the point coverage by using the ARC/INFO command NODEPOINT, in which each node of the grid was converted into a point in the new datalayer. Next the SPC northing and easting of each point was added to the attribute database (.PAT) using the command ADDXY.

The GRID10K.PAT contains two items of note:

		X-COORD		the number of feet east of the SPC origin
		Y-COORD		the number of feet north of the SPC origin

MassGIS carefully proofread the SPC coordinates of the quad corners.

MassGIS is maintaining this datalayer.

Last Updated 7/14/2004
Site Policies