PERMFILE123911

• Permit No: C1981034
• IBM Index Class Name: Permit File
• Doc Date: 9/9/1982
• Section_Exhibit Name: APPENDIX I Hydrology Part 2
• Media Type: D
• Archive: No

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After deposition and possible reworking of the fourth
terrace, local streams underwent considerable downcutting
prior to a period of deposition in which the alluvial
material now forming the third terrace (designated Qt3 on
Map 7) was deposited. This terrace is currently
approximately 100 feet above the modern stream channel of
Ward Creek. The alluvium of the Qt3 terrace consists of
gravels and cobbles in a matrix of reddish-brown fine
sediment. The cobbles and gravels are basalt. The
reddish-brown sediment is thought to be volcanic as its
color is indicative of oxidized volcanic material, and it is
strikingly different from the black basalt cobbles and the
grayish-brown Mancos clays which it overlies.
After deposition of the third terrace, extremely large
mudflows, originating far upstream, occurred which covered
most of the Mesaverde Group in the study area and Mancos
material downstream. The terminus of these mudflows was in
the narrows areas of the valleys in the southern portions of
Sections 13 and 14, T13S, R95W (approximately a mile south
of the Red Canyon Mines; see Map 7). These mudflows,
designated as Qaf on Map 6, cover most of the surface of the
mapped area. This alluvial fan material, like the third and
fourth terraces above it, consists of basalt cobbles and a
matrix of reddish-brown volcanic sediment. (The sheer size
of these fans makes it difficult to interpret them
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