Paul D. Ryan is Emeritus Professor of Geology at NUI Galway, Ireland, with fifty years of experience in the geology of western Ireland. He has 107 publications including books, maps, software and articles with over 42,000 citations, an 'h index' of 53 and an 'i10 index' of 125 (GoogleScholar, 09/01/22). Paul co-edited 'Arc-Continent Collision' in the Springer Frontiers Series which, from 2011-2018, recorded some 42,000 chapter downloads ('top 25%').