,Geology of Parts of The Upper Mississippi Valley Zinc ...
ZINCLEAD DISTRICT GEOLOGY OF THE DUBUQUE SOUTH QUADRANGLE, IOWAILLINOIS By C. ERVIN BROWN and JESSE W. WHITLOW ABSTRACT The Dubuque South quadrangle in the southwestern part o:f! the Wisconsin IllinoisIowa zinclead district is an area of 52 square miles in Iowa and 3 square miles in Illinois.