First Glaucony - a consistently thick bed. May locally include horizon of main clay and be joined with ss above this clay, but can't prove exactly where this horizon is when it tenses out. South of Creek main bed goes out abruptly and a coarse zone of ss with clay pellets that comes in locally near top of first Glaucony may be this horizon. A small amount of clay was found at this break in AIN- 48-95, #1. The plant fossils commonly found mixed in float with marine fossils below first Glaucony, are from within first Glaucony - see section AIN-48-93 #18.