Topics
- What is a shapefile?
- More about shapefile data
- What is a DOQQ?
- Can I use ArcView?
- What projection is used for these data?
- Can I get data in another projection?
- Where can I get more data?
- What is Federal Geographic Data Committee (FGDC) metadata?
- About MrSID (Multi Resolution Seamless Image Database)
What is a shapefile?
ArcView's format for storing location, shape, and attribute information of geographic features. After selecting and downloading a self-extracting file from the shapefiles libraries, double-click on the file to extract the following files:
.html
Metadata documentation
.shp
a spatial data file for shape and location information
.dbf
the attribute data file is a dBASE file that stores information about the features in shape file
.sbx
the spatial index file for spatial data
.shx
another spatial index file
.sbn
another spatial index file
It is important not to rename any of these files and to keep them in the same directory. ArcView needs all of these files to be present in order to properly display the layer. Once the above files are created on your computer, you may either use ESRI ArcView software.
More about shapefile data
Format
The District's GIS data are created and stored using the Environmental Systems Research Institute's (ESRI) Arc/INFO software. In an effort to increase the accessibility of these data to the widest possible user community, the data are available at no charge from the Internet in the ESRI Shapefile format. This format can be easily used in a variety of GIS software packages. Translation of files to formats other than those described here is the sole responsibility of individuals downloading the data.
Coordinate system
Projection: Universal Transverse Mercator (UTM) Projection,
Zone 17
Datum: North American Datum of 1983, 1990 adjustment
Horizontal Units: Meters
Vertical Units: Feet, NGVD 29, unless otherwise specified in
the metadata files for individual layers.
Metadata
Metadata describing how each dataset was created is included in each self-extracting PKZIP file as an HTML file. This includes appropriate use of data and complies with the Federal Geographic Data Committee (FGDC) standard.
Spatial coverage
Spatial coverage is a function of the density of points, lines or polygons making up a particular dataset. The data are organized into State-wide, District-wide, or in subsets of the United States Geological Survey's (USGS) 1:100,000 quadrangles.
What is a DOQQ?
Digital Orthophoto Quarter Quadrangle. For more information, please visit USGS's site.
Can I use ArcView?
Of course you can! If you have purchased the ArcView software from ESRI, then you can view both the shapefiles and DOQQs with this software. However, in order to view the MrSid files, you must load the appropriate extension which can be done by selecting Extensions in the File menu in ArcView.
What projection is used for these data?
Universal Transverse Mercator (UTM) Projection, Zone 17. The horizontal units are in meters.
Can I get data in another projection?
We supply both shapefiles and imagery as is; projection or unit changes require ESRI's Arc/Info or a similar GIS program.
Where can I get more data?
More data can be found at the Department of Environmental Protection or the Land Boundary Information Systems sites.
What is Federal Geographic Data Committee (FGDC) metadata?
See their web site for details.
About MrSID (Multi Resolution Seamless Image Database)
The previous version of the MrSID Stand Alone Viewer is no longer available from Lizard Tech.
If you already have the earlier version MrSID Viewer on your pc, it will continue to work in the manner you are accustomed to for viewing MrSID images and will still export MrSID files to tif files.
If you need a viewer for MrSID images, then go to the following link to download a free trial version of the ExpressView plug-in or the free trial GeoExpress Viewer. The new version will only work for PCs using Windows 98, ME, NT, 2000 or XP. It will view MrSID and tiffs.
Once you have downloaded the plug-in or the viewer, follow the direction and read the Help section.
For a quick start using GeoExpress View; Open GeoExpress View, then
- Click new project
- Then click on the + located in the Project 1 window
- Select the file(s) then click open
- The images appear in the viewer
- If needed, save as a project
Download the free trial GeoExpress Viewer
View a brief tutorial for the original MrSID stand alone viewer created by SWFWMD GIS section.
