IODP SEDIS - Thesaurus -

Millbrig Bentonite Bed
BT	Chronostratigraphic Units
	.Phanerozoic
	..Paleozoic
	...Ordovician
	....Middle Ordovician
	.....Millbrig Bentonite Bed
RT	Iowa
	Missouri
	Illinois
	Wisconsin
	Minnesota
	Decorah Shale
SN	Of Glencoe Member of Spechts Ferry Formation in NW Illinois and Wisconsin. Also may be of Decorah Shale in Iowa, Minnesota, and Missouri. Added to Thesaurus in 1995.