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The effects of geologic structure on topographic form within the driftless area. The gently undulating, lower slopes are underlain by Maquoketa Shale, the steep hills in the background are of the overlying Niagaran Limestone. Graf, Iowa, late 1890s or early 1900s
Located south from Lattner's, near Graf.
Beds of passage, Iowa, late 1890s or early 1900s
Section 10, Twp. 90 R. 4,
Beds of passage, Iowa, late 1890s or early 1900s
Twp. 90. R. VI, Section 10
The effects of geologic structure on topographic form within the driftless area. The gently undulating, lower slopes are underlain by Maquoketa Shale, the steep hills in the background are of the overlying Niagaran Limestone. Graf, Iowa, late 1890s or early 1900s
Located south from Lattner's, near Graf.
Beds of passage, Iowa, late 1890s or early 1900s
Section 10, Twp. 90 R. 4,
Beds of passage, Iowa, late 1890s or early 1900s
Twp. 90. R. VI, Section 10