2007 Cahokia excavation reveals colorful layered soil construction. An emergency preservation excavation in 2007 removed approximately 30,000 cubic feet from the side of Monks Mound Excavation revealed alternating layers of colored soil: white, red, blue, black, and brown throughout the mound construction The soil colors varied in thickness and composition through different layers
In 2007, an emergency preservation repair addressed a large slump area on the eastern side of Monks Mound. The repair involved cutting large stair steps, approximately seventy feet long, up the steep slope to stabilize the damage. Future slumping issues are anticipated, and the area was later backfilled with monitored soil to prevent further collapse.
Key Facts
- An emergency preservation excavation in 2007 removed approximately 30,000 cubic feet from the side of Monks Mound
- Excavation revealed alternating layers of colored soil: white, red, blue, black, and brown throughout the mound construction
- The soil colors varied in thickness and composition through different layers
- Archaeologists previously claimed nearby ponds were borrow pits for building materials, but they don't provide nearly enough material
- Soil was likely transported to the site in canoes or on rafts via the nearby Mississippi River
- Evidence of canals connecting to the Mississippi River has been found at the site
Related site: Cahokia Mounds State Historic Site — view location, images, and history on the Ancient Nerds map.
Source: The Roundtable Chronicles by Institute for Natural Philosophy