MINOR MORAINES--Annual moraines, small moraines, corrugated moraines, or transverse ridges.  Composed chiefly of till.  Most of the ridges delineate the configurations of vanished retreating ice margins.  Local relief of ridges typically is 1-5 m
ICE-MOLDED OR ICE-SCOURED LANDFORM--Drumlin, rock drumlin, or fluting.  Long axis of symbol is parallel to the direction of ice movement.  Some symbols represtne more than one landform
INFERRED LIMIT OF A GLACIAL READVANCE MARKED BY THE DISTAL MARGIN OF GLACIOTECTONIC DEPOSITS OR GLACIOTECTONIC STRUCTURES
ESKER--Subglacial or englacial stream deposit
INTERLOBATE MORAINE--Formed at the junction of two ice lobes
MARGINAL END MORAINE--Single till ridge deposited along the margin of an ice lobe
ICE-MARGIN ALIGNMENT INTERPRETED FROM ICE-MARGIN DRAINAGE CHANNELS AND TILL RIDGES
BURIED BEDROCK VALLEY OF THE ANCESTRAL MARIAS RIVER
BURIED BEDROCK VALLEY OF THE ANCESTRAL MISSOURI RIVER
LIMIT OF ILLINOIAN GLACIATION ON THE SWEET GRASS HILLS
LIMIT OF LATE WISCONSIN GLACIATION ON THE SWEET GRASS HILLS
LIMIT OF A LATE WISCONSIN GLACIAL READVANCE, OR POSITION OF A SIGNIFICANT STILLSTAND OF AN ICE MARGIN