Geology on Rosthwaite Fell

I found this wonderful paper on the geology of Rosthwaite Fell which explains its place in the Scafell Caldera. http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount289.pdf The summit rocks pictured yesterday are Crinkle Tuffs and the abstract suggests that these might be ignimbrites. As such it would be the result of a pyroclastic flow. If I ever go again I'll know to look more carefully https://en.wikipedia.org/wiki/Ignimbrite . The rock under Tarn at Leaves is Rosthwaite Rhyolite. Scafell must have been a pretty impressive volcano.