39 FAA Chart Users’ Guide - VFR Symbology - Sectional and Terminal Area Charts HYDROGRAPHY (Continued) Salt Evaporators and Salt Pans Man Exploited  Hummocks and Ridges Peat Bogs  Rice Paddies Extensive areas indicated  by label only. Springs, Wells and Waterholes Permanent Snow and Ice Areas Glaciers Glacial Moraines Ice Cliffs Snowfields, Ice Fields And Ice Caps  Foreshore Flats Tidal flats exposed at low tide. Swamps, Marshes and Bogs Mangrove And Nipa Cranberry Bogs Land Subject To Inundation Tundra Ice  Permanent Polar Ice Pack Ice Ice Peaks