“…Silurian-aged evaporite deposits, e.g., the Salina Group, merit consideration; however, Salina Group evaporites generally are absent (or depleted) from bedrock underlying northern Lake Michigan (Wold, 1980;Wold et al, 1981;Aminian et al, 1987;Sonnenfeld and Al-Aasm, 1991;Black, 2012). Portions of these evaporite deposits dissolved during the Devonian, resulting in collapse features (Wold, 1980;Black, 1983Black, , 2003 and culminating with the formation of the Mackinac Breccia (Landes, 1945;Wold, 1980;Aminian et al, 1987;Black, 2003Black, , 2012. If remnants of Salina Group evaporites persist underneath northern Lake Michigan-perhaps as recycled evaporites present in younger (Devonian) formations (Sonnenfeld and Al-Aasm, 1991)-then these remnants could affect pore-water chemistry on a localized scale.…”