Two thick tephra deposits, collectively known as the Finlay tephras, are situated between sand, silt, mud and gravel in the Dease Lake and Finlay River areas. They both range in composition from phonolitic to trachytic and are high in iron(II) oxide, indicating that the tephras were likely extruded from a single volcano. Radiocarbon dating of terrestrial plant macrofossils directly overlying the youngest tephra deposit suggest an early Holocene age for this volcanic material. Because Level Mountain has received little scientific study and it is debated on whether or not Holocene volcanic rocks are present, the volcano is a possible source for these tephra deposits along with Hoodoo Mountain, Heart Peaks and the Mount Edziza complex.