Frequently Asked Questions

Why are fossils preserved so well in Foulden Maar?

Over time, plants and animals fell into the lake and sank to the bottom. The lake bed is anoxic, meaning it lacks oxygen, and so they become pickled. The sediment is made up of diatoms, a microscopic plant made of silica. These form a bloom on the lake’s surface every spring and summer, then die off and sink to the bottom to create a 1mm thick blanket across the lake bed, preserving whatever had fallen in that year. This process has been repeated year after year for over 100,000 years to create an incredibly high-quality and detailed fossil record.