How did Komitake contribute to the formation of Mount Fuji?

Komitake served as one of the earliest precursors to Mount Fuji and forms the foundation of the mountain, specifically its north slope.1

The present-day mountain is a composite of three successive volcanoes, with Komitake at the bottom. Over millennia, lava and other ejecta from the subsequent volcano, Ko Fuji ("Old Fuji"), covered most of Komitake. Despite this, the top of the Komitake cone continued to protrude from the slope of Ko Fuji, contributing to the structural history of the mountain before the final, most recent layer, Shin Fuji ("New Fuji"), helped produce the mountain's current tapered form.21