Pg. 10, 11, 13 (table1). Huronian series not used in this report. Correlation of bedded Precambrian rocks of Marquette trough with the type Huronian sequence north of Lake Huron by early workers in the Lake Superior area (Hunt, 1861; Kimball, 1865; Irving, 1885) is now subject to considerable doubt. Applying to the Kiernan area the practice followed during recent Survey work in central Dickinson County, Michigan, crystalline rocks older than the Huronian of former reports are called lower Precambrian instead of Archean; rocks formerly correlated with the Huronian are now referred to the middle Precambrian; Precambrian rocks younger than those formerly designated as Huronian are now called upper Precambrian rocks. Subdivision of lower, middle, and upper Precambrian rocks of the Kiernan quadrangle into formal groups or series has not been attempted in the present report.

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Pg. 30 (table 1), 33. Term Huronian not used in Iron and Dickinson Counties, Northern Peninsula, northwestern Michigan (Lake Superior region); replaced with Animikie series (middle Precambrian). Not used because of uncertainty of correlation with the type Huronian of Canada.

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