Sentence Examples with the word Turritella

The oldest is the Midway limestone and clays in a narrow strip whose western limit is nearly parallel to the western boundary of the Selma chalk; it includes: the Clayton formation, characterized by the hard blue Turritella limestone (so named from the frequent fossil (Turritella mortoni); and Porters Creek (previously called Flatwoods) clay, which is grey, weathering white, and is occasionally overlain by grey fossiliferous sandstone.