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89:(UTM), but are sometimes cast on the State Plane rectangular coordinate system. Intermediate-scale DLGs are sold in 30- by 30-minute sections that correspond to the east or west half of the 100K quadrangle map, and each of the 30-minute sections is distributed in four 15- by 15-minute cells and is cast on the UTM coordinate system. Small-scale DLGs are sold in state units and are cast on either the
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137:(HP), Non-vegetative features (NV), Survey control and markers (SM), Man-made features (MS) and Vegetative surface cover (SC). Large-scale DLGs offer all nine layers, while intermediate-scale DLGs offer the five layers of PLSS, BD, TR, HY and HP. Small-scale DLGs offer the five layers of PLSS, BD, TR, HY and MS.
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Large-scale DLGs are available in optional format and will also be available in SDTS format as the data from each state is converted. Intermediate-scale DLGs are available in optional format and the HY and TR layers are also available in SDTS format. Small-scale DLGs are available in both optional
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DLGs are normally derived from USGS maps or USGS map-related sources. DLGs are distributed at three different scales: large-scale, which normally correspond to the USGS 7.5- by 7.5-minute, 1:24,000 and 1:25,000-scale topographic quadrangle map series, 1:63,360-scale for
44:(USGS). DLGs are collected from USGS maps and are distributed in large, intermediate and small scale with up to nine different categories of features, depending on the scale. They come in optional and
81:; intermediate scale, which are derived from the USGS 30- by 60-minute, 1:100,000-scale map series; and small-scale, which are derived from the USGS 1:2,000,000-scale sectional maps of the
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DLGs are available in two different formats: optional format, a simple-to-use format that incorporates an 80-byte logical record length, the UTM ground coordinate system, and
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153:(SDTS) format, a format that facilitates transferring of spatial data between different computer systems.
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of 1927 (NAD27) or the North
American Datum of 1983 (NAD83). USGS DLGs are
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Nine different categories of features, or layers, are available in DLGs:
101:, depending on the distribution format. All DLGs are referenced to the
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linkages contained in line, node and area elements; and
87:Universal Transverse Mercator coordinate system
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85:. Large-scale DLGs are usually cast on the
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175:"USGS Fact Sheet, Digital Line Graphs"
7:
83:National Atlas of the United States
36:map feature represented in digital
91:Albers equal-area conic projection
14:
40:form that is distributed by the
246:United States Geological Survey
151:Spatial Data Transfer Standard
46:Spatial Data Transfer Standard
1:
111:geographic information system
54:geographic information system
95:geographic coordinate system
129:(BD), Transportation (TR),
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68:Map produced with DLG data
123:Public Land Survey System
219:National Atlas home page
209:USGS Digital Line Graphs
107:topologically structured
50:topologically structured
251:GIS vector file formats
109:for use in mapping and
77:and 1:30,000-scale for
52:for use in mapping and
48:(SDTS) format and are
99:latitude and longitude
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42:U.S. Geological Survey
21:
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19:
141:Distribution formats
113:(GIS) applications.
103:North American Datum
56:(GIS) applications.
214:USGS Product Guides
157:and SDTS formats.
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26:Digital Line Graph
22:
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225:The National Map
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180:. Archived from
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117:Data categories
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203:External links
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93:system or the
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187:on 2009-08-25
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189:. Retrieved
182:the original
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34:cartographic
29:
25:
23:
241:Cartography
135:Hypsography
131:Hydrography
79:Puerto Rico
60:Description
235:Categories
191:2009-08-11
161:References
127:Boundaries
20:USGS logo
147:topology
125:(PLSS),
32:) is a
133:(HY),
75:Alaska
38:vector
185:(PDF)
178:(PDF)
97:of
30:DLG
237::
24:A
194:.
28:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
