1:1M Geologic Map of the Dao, Harmakhis, and Reull Valles Region, Mars
February 2, 2018

The original geologic map was created in 2005 from Viking basemap imagery. To make this map more useful with modern data it has been georeferenced to align with the more modern 2014 THEMIS Daytime IR imagery. Links used to transform the data are included with this documentation. A polyline feature class was created to digitize contacts at 1:250k and attributed with contact type. A polygon feature class was created from this polyline feature class, attributed with geologic unit labels, and symbolized based on RGB values identified from the map sheet TIFF in Adobe Photoshop.

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Data are saved in a feature dataset in I2557_DaoHarmakhisReullValles_1M_clon0.gdb

 I2557_DaoHarmakhisReullValles_1M_clon0_GeoContacts (polyline feature class)
 I2557_DaoHarmakhisReullValles_1M_clon0_GeoUnits (polgyon feature class)

GCS_Mars2000_Sphere
Projection    	Plate_Carree

Zunits        NO                                                                
Units         METERS                                                            
Xshift        0.0000000000                                                      
Yshift        0.0000000000                                                      
Parameters 3396190.0000000000  3396190.0000000000                               
0.000 /* longitude of central meridian                                   
000.000 /* latitude of true scale                                          
0.00000 /* false easting (meters)                                       
0.00000 /* false northing (meters)

Separate shapefiles of the two feature classes are located in the ...Data/Shapefiles/ directory.

The coordinate system used for this digitization is based on the coordinate system stated on the map sheet and is stored in ...Documentation/CoordinateSystems/ directory.

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Basemaps have not been included in this download package, but the most current base using THEMIS data is available through ArcGIS Online or can be downloaded at the following link:
https://astrogeology.usgs.gov/search/map/Mars/Odyssey/THEMIS-IR-Mosaic-ASU/Mars_MO_THEMIS-IR-Day_mosaic_global_100m_v12

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Below are the RGB values sampled from the scanned map sheet used to symbolize geologic units and saved as a layer (*.lyr) file in the ...Data/LayerFiles/ directory. 

GeoUnit		RGB
Ada  221 179 167
As   255 222 185
AHv  189 214 48
AHk  126 203 195
AHvi 62  185 157
AHch 65  149 209
AHv2 0   181 233
AHv1 113 187 236
AHpp 122 191 206
AHm  208 173 107
Hps  249 255 139
HNh  255 234 203
NH1  224 203 174
Nm   217 200 180
cf   250 190 166
c3   252 243 2  
c2   131 205 118
c1   194 117 45
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For more information, contact:
Michelle Barton
mbarton@usgs.gov
USGS Astrogeology Science Center
Flagstaff, AZ
(928)556-7177