Following Paul Gannon's book, we went to see the volcaniclastic sediments on Bowfell on the way up from Three Tarns. These layers are the back on the Great Slab, which is the top sloping layer of these sediments. These layers are apparently formed from dust and ash from volcanoes that settled in the bottom of lakes in the large Scafell Caldera. He talks about volcaniclastic sandstone so I went to see the thick darker band. It is made of lumps a bit like large barnacles. He also says that some layers were disturbed by earth tremors before they had fully solidified and so have swirled patterns. I found these
