Abstract As we have seen, the main ‘professional’ mapping of the Lakes was more or less completed by the 1880s, though the Survey continued to publish memoirs on the region for some time after finishing the fieldwork, before returning to the region in the twentieth century to revisit some of the old questions; and then it undertook a major resurvey after 1982 (see Chapter 14). So it was that much of the detailed research from the 1880s to the outbreak of World War I was undertaken by ‘amateurs’. Of these, the most important were Nicholson, whose ideas were discussed in Chapter 3, John Postlethwaite (see Chapter 6), John Edward Marr (1857–1933) and J. F. N. Green (see Chapter 6). There are good archival sources on Marr, in that all 65 of his field notebooks and an unnumbered ‘journal’ survive at the Sedgwick Museum, together with a few letters. 1 The notebooks reveal that from 1874 until 1927 Marr spent a substantial part of almost every year in the Lakes; and he wrote what became the standard book on Lakeland geology for many years ( Marr 1916 ). 2 To my knowledge, rather little on Green has survived beyond his published works. Marr’s family came from Bolton-le-Sands in Lancashire, and he attended school at Lancaster Grammar. While there, he made the acquaintance of the Surveyor Richard Tiddeman, then working in the district, and accompanied him on several field-trips. Marr’s unnumbered journal (for 1874–1876) shows that he was examining human

Abstract From the time that the Geological Survey was established in 1835, its officers tramped the country, entering information on topographic maps, and colouring them according to the determined rock types, so that – through the preparation and publication of maps – the essential tools for elucidation of the geological structure and history of the United Kingdom were prepared (or constructed), and much information was gathered of economic significance. By and large, the team of surveyors worked systematically across the country from the SW northwards, though some preference was given to regions of commercial significance, with important mineral deposits. The task was a large one, which even now is not complete. It posed difficulties in that geological theories, and stratigraphic subdivisions, were altered during the course of the work; and sometimes there were differences of factual, methodological or conceptual opinion between the Survey officers themselves and in relation to the ideas of ‘amateur’ geologists – which according to the accepted terminology of the time might include anyone from impecunious collectors such as John Bolton to university professors such as Sedgwick, Nicholson or Lapworth. This terminology may seem odd today, but certainly it was the Survey staff who earned their money by the making of geological maps; and they were in the field for much longer stretches of time each year than were the ‘amateurs’. Indeed, one way or another, they were at it all the time. So they regarded themselves as the ‘professionals’. On the other hand, they might sometimes be

Abstract Rock successions in Britain and Ireland, and more especially those in Wales, were instrumental in the founding and naming of the Ordovician System, and the Anglo-Welsh series established both initially and subsequently were used widely as a standard for Ordovician chronostratigraphy. Although now largely superseded in the global scheme of series and stages, they retain their local and regional importance. The Ordovician System in Britain and Ireland documents the history of a segment of the Earth's crust that incorporated opposing peri-Gondwanan and peri-Laurentian/Laurentian margins of the Iapetus Ocean during its closure, and is accordingly complex. The complexity arises from the volcanic and tectonic processes that accompanied oceanic closure coupled with the effects of eustatic sea-level changes, including the far-field effects of the Late Ordovician glaciation. For the past three decades, Ordovician successions in Britain and Ireland have been discussed in terms of terranes. Here we review Ordovician successions in each terrane, incorporating the results of recent research and correlating those successions via biostratigraphical schemes and radiometric dates to the global Ordovician series and stages.

Abstract For some forty years after Adam Sedgwick took to the field in the Lakes in 1822, he was virtually the only major geologist to make the region one of his main objects of study. We have seen how he made considerable efforts to sort out the stratigraphy of the southern Lakes, relating his work there to his investigations in Wales, but to a large extent he left the central volcanic region alone; likewise the Skiddaw Slates - apart from claiming them for his Cambrian System on the basis of their apparently meagre fossil contents, as collected by Ruthven. The man who took up from where Sedgwick left off was Robert Harkness (1816–1878) (see Fig. 3.1 ). 1 His family came from Ormskirk, near Liverpool, but he attended school in Dumfries in SW Scotland, his father’s home town. From there he went to Edinburgh University, where he studied under the geologists Robert Jameson and James David Forbes, and the chemist Thomas Charles Hope. In his early twenties Harkness was making geological investigations in Lancashire, particularly among the coalfields and the rocks of the New Red Sandstone. In 1848, the family moved to Dumfries, from which centre Harkness, being of independent means, began geological investigations among the rocks of the Southern Uplands, including the region near Moffat, which, rich in graptolites, later became a classic site through the work of Charles Lapworth (1842–1920) ( Hamilton 2001 ). Thus early in his career, Harkness became familiar with these Lower Palaeozoic fossils. In fact, his

Abstract The Lower Palaeozoic accretionary thrust belt forming the Southern Uplands terrane lies to the northwest of the Iapetus Suture and to the southeast of the Southern Upland Fault ( Fig. 6.1 ). The former structure marks the line of closure of the Iapetus Ocean and of collision between the continental blocks of Laurentia and Avalonia; it underlies the Solway Firth and approximates to the line of the Anglo-Scottish border. The latter structure separates the Southern Uplands terrane from the mainly Upper Palaeozoic rocks of the Midland Valley terrane and in particular the Ballantrae Complex. The following sections have been contributed by B. J. Bluck (Ballantrae), P. Stone (Southern Uplands stratigraphy, and provenance) and G. J. H. Oliver (Southern Uplands structure, metamorphism, and geodynamics).

Abstract The evolution of Silurian geology in Britain was strongly influenced by the final stages of the closure of the lapetus Ocean ( Fig. 4.1 ). Avalonia united with Baltica at around the time of the Ordovician-Silurian boundary (443ma) and impacted with the Laurentian margin ( Fig. 4.1 ), between 440 Ma and 420 Ma, probably during the Llandovery or Wenlock ( Soper & Woodcock 1990 ; Cocks & Torsvik 2002 ). The Avalonian margin apparently remained tectonically active throughout the final stages of convergence as indicated by sporadic volcanicity and evidence of early to mid Silurian crustal extension within the Welsh Basin ( Fig. 4.2 ). The initial effects of the collision of Laurentia and Avalonia particularly affected the development of the Lakesman Basin (see section on Lakesman Basin), but later, as Laurentia and Avalonia were driven more tightly together, crustal shortening ended the regime of extensional subsidence in the Welsh Basin. An influx of sediment from the uplifted land to the north and from the land area (Pretannia) to the south caused the basin to become progressively filled in the Late Silurian (Woodcock in Aldridge et al. 2000 ) as the basin underwent thermal subsidence prior to the onset of compression. However, this was punctuated by an interval of southeasterly migrating crustal flexure and increased subsidence, as Laurentia or the advancing accretionary prism overrode Avalonia from the north (King 1994).