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Stratigraphic relations between Bonanza Center and adjacent parts of the San Juan volcanic field, south-central Colorado Dennis L. Bruns, Rudy C. Epis, Robert J. Weimer, and Thomas A. Steven, 1971, pp. 183-190 in: San Luis Basin (Colorado), James, H. L.; [ed.], New Mexico Geological Society 22nd Annual Fall Field Conference Guidebook, 340 p.
This is one of many related papers that were included in the 1971 NMGS Fall Field Conference Guidebook.
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183 STRATIGRAPHIC RELATIONS BETWEEN BONANZA CENTER AND ADJACENT PARTS OF THE SAN JUAN VOLCANIC FIELD, SOUTH-CENTRAL COLORADO
by DENNIS L. BRUNS', RUDY C. EPIS1,
ROBERT J. WEIMER' AND THOMAS A. STEVEN2
INTRODUCTION northwest of Saguache, Colorado ( figs. 1 and 2), where Saguache Creek and its tributaries East Pass, Sheep, Jacks, Stratigraphic relations of units derived from the Bonanza Cross, Middle and Ford Creeks have cut numerous val- volcanic center in the northeastern part of the San Juan leys into the Cenozoic volcanic rocks. These exposures volcanic field and units from sources in the central and show that many of the rocks from the Bonanza center are western parts of the field are well exposed in the Trickle generally equivalent in age to the early intermediate rocks Mountain and Lake Mountain NE quadrangles, 8-16 miles in the rest of the San Juan volcanic field, and are older
Colorado
Area of Fig.1 1
0 10 20 Miles 285 West Elk Scale Volcanic Field
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FIGURE 1. Location of the Trickle Mountain and Lake Mountain NE quadrangles in the San Juan volcanic field, Colorado.
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