Stac Fada Member

The Stac Fada Member is a distinctive layer towards the top of the Mesoproterozoic Bay of Stoer Formation, part of the Torridonian Supergroup. This rock unit is generally 10 to 15 metres thick and is made of sandstone that contains accretionary lapilli and many dark green glassy fragments of mafic composition. Evidence for a bolide impact near Ullapool or Lairg has been published and refined in studies in 2008 and 2015. It is prospectively among the twenty largest impact craters on Earth, is 40km across, and dates from 1. 2 billion years ago.

The Stac Fada Member is a distinctive layer towards the top of the Mesoproterozoic Bay of Stoer Formation, part of the Torridonian Supergroup. This rock unit is generally 10 to 15 metres thick and is made of sandstone that contains accretionary lapilli and many dark green glassy fragments of mafic composition. Evidence for a bolide impact near Ullapool or Lairg has been published and refined in studies in 2008 and 2015. It is prospectively among the twenty largest impact craters on Earth, is 40km across, and dates from 1. 2 billion years ago.