The state of Iowa; something of its history, its institutions, its resources and natural advantages . PH1MC5 MALI 51. CWSi3K ,s jsu/i; AR- aiiiDiwC 52 In Fayette, Winneshiek and Howard counties the Maquolveta forma-tion tal<;es on characteristics altogether different from those which itexhibits near Dubuque. It is much less argillaceous, and some of thebeds, as at Ft. Atkinson, actually become heavy dolomite suitable forbuilding stone. The plastic clays of the formation have been used forbrick and pottery making. The maximum thickness is about 200 feet. SILURIAN.—The Silurian is represented
The state of Iowa; something of its history, its institutions, its resources and natural advantages . PH1MC5 MALI 51. CWSi3K ,s jsu/i; AR- aiiiDiwC 52 In Fayette, Winneshiek and Howard counties the Maquolveta forma-tion tal<;es on characteristics altogether different from those which itexhibits near Dubuque. It is much less argillaceous, and some of thebeds, as at Ft. Atkinson, actually become heavy dolomite suitable forbuilding stone. The plastic clays of the formation have been used forbrick and pottery making. The maximum thickness is about 200 feet. SILURIAN.—The Silurian is represented in Iowa by a single se-ries which is generally referred to as the Niagara limestone. Theformation has a thickness of more than 300 feet. Certain parts of itare very rich in chert, but, taken as a whole, the Niagara of Iowa issingularly free from shale. Throughout its entire range the calcareousconstituent has been altered to dolomite. Notwithstanding the generaluniformity of the material composing the formation, the characteristicsof the beds vary within quite large limits. Some parts break intoshapeless mass
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectlouisia, bookyear1904
