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USGS
Data Sources and Processing Instructions
Common
Data Types & Standards
Digital Elevation Models
(DEMs) | Digital Orthophoto Quads(DOQQs)
| Digital Line Graphs(DLGs) | Digital
Raster Graphics (DRGs) | Landsat
Satellite Images | Land Use Land Cover (LULC)
| Spatial Data Transfer Standard(SDTS)
Note:
these tools and extensions are already loaded on computers in Branner
Earth Sciences Library.
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Importing
Digital Line Graphs (DLGs)
into ESRI GIS software |
The
following instructions apply to the Spatial Data
Transfer Standard (SDTS)
format. For the Optional Format,
please click here.
Instructions
for importing SDTS DLGs into ESRI's:
Importing
SDTS format DLGs into ArcGIS
In
ArcToolbox, , select Import to Coverage > Import
SDTS Wizard. The wizard steps you through the
process, including relating the new layer to its
associated data dictionary.
Importing SDTS format DLGs into ArcView 3.x
Users
in Branner Earth Sciences Library
1.
Download and unzip 1:24,000, 1:100,000 or 1:2,000,000
DLGs in SDTS format from the EROS
Data Center.
2. You may use the DLG2SHP Utility loaded on the
GIS machines.
3. Directions for how to use this helpful utility
may be found at the GIS
Tools website.
Users
outside Branner Earth Sciences Library
1.
The U.S.G.S. has put together a helpful set of instructions
for retrieving and unpacking SDTS format DLGs, including
a description of the data dictionaries. You may
view the document: sdts_tutorial.
(It includes instructions for DEMs as well.)
2. For instructions on importing these DLGs into
ESRI software, read the instructions from the US
Fish & Wildlife. Their instructions utilize
several free utilities, all of which are available
at ftp://ftp.blm.gov/pub/gis/sdts/dlg/
3. Download SDTS2dlg.exe, dlgbld.exe, and dosxmsf.exe
These utilities convert a DLG in SDTS format into
an Optional Format DLG. You should read our
instructions for importing the newly created
Optional DLG into ArcView.
Importing
DLGs into Workstation ArcInfo
1. The
ARC command SDTSIMPORT produces coverages that have feature
attributes residing in separate "normalized" tables, some
of which contain "one to many" relationships. Manual processing
of these attribute tables can be very complicated for the
novice ArcInfo user, so I recommend using the following AML
available from the USGS sdts2cov.zip
2. Follow the instructions in the included readme file.
This AML simplifies the attribute structure by attaching all
of the attributes from the attribute modules directly to the
feature attribute tables. This is not as efficient, because
many of the attributes get duplicated, but it makes accessing
the attributes much easier.
| Spatial
Data Transfer Standard (SDTS) |
- The USGS also provides
a directory
for public domain software used when working with SDTS. There
you will find ESRI product utilities, DEM conversion tools, information
for programmers, and a number of links to other resources.
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| Land
Use Land Cover (LULC) |
The
Land Use and Land Cover (LULC) data files describe the vegetation,
water, natural surface, and cultural features on the land surface.
The LULC mapping program is designed so that standard topographic
maps of a scale of 1:250,000 can be used for compilation and organization
of the land use and land cover data.
Datasets are
available for download from:
Note: These
LULC files haven't been updated recently, so you may want to explore
other
resources for land cover data, especially the new seamless
National Land Cover
Dataset Server.
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Last modified:
July 26, 2006
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