- Timeframe: The Sturtian glaciation occurred approximately 720 to 660 million years ago during the Cryogenian Period.
- Description: The Sturtian glaciation is one of the earliest known global glaciations in Earth’s history. During this time, vast ice sheets covered large portions of the planet, including areas near the equator. These ice sheets extended over present-day continents, and some evidence suggests that glaciers may have even reached the ocean’s edge. The glaciation led to a significant drop in sea levels due to the accumulation of ice on land.
- Environmental Impact: The Sturtian glaciation had profound effects on the environment. The Earth’s surface temperature dropped significantly, causing a “Snowball Earth” scenario, where most of the planet’s surface was covered in ice. This extreme cooling likely resulted from the reflection of sunlight by the ice and snow, preventing the absorption of solar radiation and perpetuating the glaciation.
- Geological Significance: The Sturtian glaciation is important in Earth’s history as it marks one of the most severe ice ages ever recorded. The massive glaciation and associated sea-level changes left distinct geological features, including glacial deposits and sedimentary layers that record the transition from ice-covered to ice-free conditions.