Of geological interest is the recent discovery by the writer of quartzite pebbles, one-half inch to three inches or more in diameter, at the base of the Lance formation in east central Montana. Most of the pebbles are of light-buff quartzite, but several porphyry pebbles were also found. The occurrence was noted while mapping the Freedom dome, about 15 miles south of Jordan, in Garfield County. Here, the Hell Creek member of the Lance formation rests on well-bedded sandstone and shale which ranges in thickness from 35 to 66 feet. This, in turn, lies upon dark shale of the Bearpaw...

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