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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>A.B. Campbell</dc:contributor>
  <dc:creator>J. E. Harrison</dc:creator>
  <dc:date>1963</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;A continuous strip of geologic maps has recently been completed along the&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Idaho&lt;/span&gt;&lt;span&gt;-&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Montana&lt;/span&gt;&lt;span&gt;&amp;nbsp;state line between Clark Fork,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Idaho&lt;/span&gt;&lt;span&gt;, and Superior,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Montana&lt;/span&gt;&lt;span&gt;. New stratigraphic and petrographic information provides the basis for stratigraphic&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;correlations&lt;/span&gt;&lt;span&gt;&amp;nbsp;and for the interpretation of facies changes&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;this part of the basin of deposition of the Precambrian&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Series&lt;/span&gt;&lt;span&gt;. Identification of facies changes is aided by the recognition of siltite (low-grade metamorphosed siltstone) as a valid rock type,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;addition to quartzite and argillite, to classify most of these rocks and to establish mappable units. The older&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;rocks (Prichard through Wallace Formations) were deposited&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;a trough whose axis trended northwestward, perhaps approximately through Libby,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Montana&lt;/span&gt;&lt;span&gt;. Subtle facies changes suggest an ancient shore line southwest of the Coeur d'Alene district,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Idaho&lt;/span&gt;&lt;span&gt;, perhaps near the present exposed edge of the&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Idaho&lt;/span&gt;&lt;span&gt;&amp;nbsp;batholith. The younger&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;formations of the Missoula Group, however, thicken markedly southeastward toward Superior. Thus, the younger&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;rocks were deposited&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;a trough whose main axis was about at right angles to that of the older trough and perhaps was near Missoula,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Montana&lt;/span&gt;&lt;span&gt;. Deposition&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;the Clark Fork area was scant and often interrupted&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;Missoula time. The young major cross-warp&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;the old&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;geosyncline undoubtedly has contributed complexities to&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;correlation&lt;/span&gt;&lt;span&gt;&amp;nbsp;farther north. Detailed petrographic studies indicate that the&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Belt&lt;/span&gt;&lt;span&gt;&amp;nbsp;rocks from the Pend Oreille area,&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;Idaho&lt;/span&gt;&lt;span&gt;, are remarkably uniform&amp;nbsp;&lt;/span&gt;&lt;span class="ScopusTermHighlight"&gt;in&lt;/span&gt;&lt;span&gt;&amp;nbsp;the mineralogic composition of similar rock types throughout 40,000 feet of strata. Further mineralogic studies are required to determine whether this uniformity is local or widespread.&amp;nbsp;&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1130/0016-7606(1963)74[1413:CAPIBS]2.0.CO;2</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Geological Society of America</dc:publisher>
  <dc:title>Correlations and problems in belt series stratigraphy, Northern idaho and western Montana</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>