We see there is a problem, it's not going away on its own, and it comes from those old sediments.

Living bacteria from 400 metres below the seafloor in 16 million year old sediment have been discovered.

Deposits of even older glacial sediment exist on every continent except South America.

Research has shown that the old sediments are no longer a threat to ecosystems.

Downstream of the crossing, older sediments will be buried beneath younger deposits.

Cast a light in the darkness, don't just churn up the same old sediment at the bottom of the river.

Because the reef grows upward, the oldest sediments are found lower in the reef.

Dinosaurs are known from this Formation, but represent specimens washed out to sea or reworked from older sediments.

More exciting still has been the recognition of many Burgess elements in older sediments.

Progressively older sediments outcrop toward the north of the basin.