Insoluble Residue Analysis of Rock Samples from the Franconia and Trempealeau Formations of the Cambrian System of Wisconsin Open-file report; contains unpublished data that has not yet been peer-reviewed. Bedrock Geology Data and Resources WOFR1935-01 Insoluble Residue Analysis of Rock Samples from the Franconia and Trempealeau Formations of the Cambrian System of Wisconsin Powell, E.H.; 1935 Report: 48 p. Download Related Collections Open-File Report View Open-File Report