Cowie Formation

The Cowie Formation is geological formation located on the Highland Boundary Fault between the fishing village of Cowie and Ruthery Head, in Aberdeenshire, Scotland. The age of this formation is controversial, originally estimated at the Middle Silurian, specifically Wenlock to Ludlow, but zircon geochronology points to the Early Devonian, Lochkovian instead. In study published in 2023, according to spore microfossils and additional zircon data, the Middle Silurian, late Wenlock age is suggested again. However, in 2024 it is considered as unsustainable because this conclusion is based on adjacent structurally separated block with different stratigraphy and sedimentology to the block with fossil productive Fish Bed. This formation preserves fossils, including a millipedes such as Pneumodesmus and Cowiedesmus that were discovered by Mike Newman in 2001, and some agnathan like Cowielepis.