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<!DOCTYPE metadata SYSTEM "http://www.fgdc.gov/metadata/fgdc-std-001-1998.dtd">
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    <product>
        <format>2.0</format>
        <title><![CDATA[Mars Geologic Map of the Dao, Harmakhis, and Reull Valles Region]]></title>
        <date>1998</date>
        <target>Mars</target>
        <scale>1:1000000</scale>
        <authors><author> K. Price</author></authors>
        <abstract><![CDATA[The geology for this map was compiled using
Viking Orbiter images on 1:500,000- scale photomosaics of the Mars
Transverse Mercator quadrangles -40262, -40267, and -40272. This
map represents a detailed extension of regional geologic mapping of
the east Hellas rim (Crown and others 1990, 1992) and is published
at 1:1,000,000 scale. The map area is on the east rim of one of the
largest impact structures in the Solar System, the
~2,000-km-diameter Hellas basin (fig. 1). Channeled plains, with
Dao, Harmakhis, and Reull Valles as the primary drainage features,
dominate much of the surface within the map area. Dao Vallis is the
downstream extension of Niger Vallis, which originates on the south
flank of Hadriaca Patera, north of the map area. Harmakhis Vallis
and Reull Vallis appear to intersect near latitutude 38°30' S.,
longitude 264°30'; Harmakhis Vallis trends southwest and Reull
Vallis trends southeast from the area of intersection. The source
area for these major outflow channels is at the intersection of two
principal rings of multiring impact basins (Potter, 1976; Schultz
and Frey, 1990; fig. 1). Hellas basin is centered southwest of the
map area, and the proposed Hesperia basin is centered northeast of
the map area (Schultz and Frey, 1990).The eastern part of the map area contains
extensive remnants of ancient mountains and crater rim materials,
along with large mesa-like features. Landforms over the entire map
area appear to have been modified by multiple erosional events
including downslope movement, eolian, and fluvial
processes.The purpose of mapping the geology of the Dao,
Harmakhis, and Reull Valles region of Mars is to refine
stratigraphic and geomorphologic relations among the geologic units
in thearea in order to better understand the nature of, relative
timing of, and interactions among martian highland surface
processes.]]></abstract>
        <seriesId>2557</seriesId>
        <quadName>Dao</quadName>
        <wkt>MULTIPOLYGON (((85 -37.5, 100 -37.5, 100 -42.5, 85 -42.5, 85 -37.5)))</wkt>
        <projection>Transverse Mercator</projection>
        <pixelResolution>Left as unknown</pixelResolution>
        <themes><theme>Cartography</theme><theme>Geology</theme><theme>Geomorphology</theme><theme>Photogeology</theme><theme>Stratigraphy</theme><theme>Planetary evolution</theme></themes>
        <forms><form>Geologic Map</form><form>Raster Data</form><form>Vector Data</form></forms>
        <mission></mission>
        <accessInstructions>1 remote-sensing map :col. ;32 x 72 cm., on sheet 91 x
110 cm., folded in envelope 30 x 24 cm.</accessInstructions>
        <minLat>-42</minLat>
        <maxLat>0</maxLat>
        <minLon>85</minLon>
        <maxLon>100</maxLon>
    </product>
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