Filters: Tags: monzonite (X) > Date Range: {"choice":"year"} (X)

Filters Date Types (for Date Range) Contacts U.S. Geological Survey Categories Image (2) Tag Types collection (2) Place (2) label (2) Tag Schemes http://www.sciencebase.gov/vocab/undefined/DenverHistoryPhotoLibrary/PhotoMedia (2) View Results as: JSON ATOM CSV

At head of Boren Creek showing monzonite stock, lines on published photo show boundary of stock. La Plata County, Colorado. 1936. At head of Boren Creek showing monzonite stock, lines on published photo show boundary of stock; Spiller and Burwell Peaks are in upper left and right corners. The jagged pinnacles along the gulch in the foreground are due to erosion of strongly altered and pyritized rocks of various kinds, view looking north from ridge east of Burwell Peak. La Plata County, Colorado. Circa 1936. Plate 4, in U.S.Geological Survey Professional paper 219. 1949. Categories: Image; Tags: La Plata County, Colorado, Monzonite, photo print Aplite dikes on one of the higher spurs in the northwestern part of the Little Ajo Mountains. Pima County, Arizona. 1932. Form a panorama; aplite dikes on one of the higher spurs in the northwestern part of the Little Ajo Mountains, viewed from the west. The smooth hill slopes ate equigranular Cornelia quartz monzonite. The craggy outcrops are aplite, commonly with blending contacts against the coarser grained rock. The dikes dip steeply to the left (north). Pima County, Arizona. 1932. Plate 1-D, in U.S.Geological Survey Professional paper 209. 1946. Categories: Image; Tags: Aplite, Monzonite, Pima County, Arizona, photo print