The start of soil formation (time zero) generally occurs following a major geologic event such as a volcanic eruption, deposition of material from a flood, landslide, or a glacial period. The soils in New England began forming after the last ice sheet retreated back into Canada between 14,000 to 10,000 YBP. The soils of New England are considered very young and are only in the early stages of profile development. Humans also cause time zero with each back hoe excavation and dump truck load.