Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 Part 2. Lyell and the development of geological science One could be forgiven for thinking that basin evolution and dynamics was a field of study developed in the later part of the twentieth century. The rapid rise in sedimentology and basin analysis would support this view. In attempting to understand, and give credit for, the origin of a particular discipline, there is often a need to identify individuals who may be regarded as the founder. Clearly with sedimentology such a man was Sorby. In his contribution, Mike Leeder argues that a case can be made that it was Lyell rather than Sorby who was the true originator of sedimentology and basin analysis. Leeder critically analyses Lyell's sedimentological descriptions and field observation as published in the Principles. Leeder demonstrates that Lyell grasped many concepts both of processes and products, indeed he recognized a number of sophisticated sedimentological concepts. Leeder further documents Lyell's willingness to abandon firmly held views. It is also clear that Lyell was not anticatastrophist as is often claimed. From Leeder's analysis it is firmly established that Lyell was engaged in and indeed contributed to establishing geology as a truly scientific discipline. Of major interest to Lyell was the concept of geological time and its divisions. Lyell's studies on Tertiary molluscs and the establishment of geological periods based upon their percentage similarity to modern forms is well known. William Berggren discusses the development of Cenozoic stratigraphy including Lyell's terms Eocene, Miocene, Pliocene and Pleistocene and suggests changes to current nomenclature and concepts. The establishment of time as a major element in geological ideas and the recognition of changing faunas and floras through time caused many difficulties to geologists in the nineteenth century. In his early work, as Tony Hallam points out, Lyell argued against organic progression. However, as data accumulated, Lyell eventually began to accept some kind of organic progression in the stratigraphic record whilst still believing in the imperfection of the fossil record. Hallam argues that it is not fair to criticize Lyell for his late and lukewarm conversion to evolution. Joe Burchfield takes the concept of time a step further and gives a considered account of how, through the course of the nineteenth century, Lyell and his contemporaries developed ideas from a general impression of the vastness of geological time to the clear recognition of a geological history of the Earth as a succession of events in the stratigraphic record and attempts to determine a chronology for the age of the Earth. If the general concensus at the end of the century gave the Earth an age of c. 100 Ma, to be disproved within a decade, no matter, the concept of geological time had been established and with it the essential scientific basis to quantify the rates of geological processes. Rapid climatic change and Quaternary glaciation provided a major challenge to Lyell. Patrick Boylan in his paper discusses Lyell's work in relation to the Glacial Theory of Louis Agassiz. Boylan documents the intensive field research of Lyell centred on his Scottish estate at Kinnordy. Lyell at first supported the Glacial Theory but hostility by a number in the Geological Society persuaded Lyell to revert to his earlier views of the importance of floating icebergs. However, by the end of his life he had begun to accept some highland glaciations but still continued to attribute deposits of the 'Glacial Period' to submergence. Whilst Lyell continued to have problems with the Glacial Theory, he was still particularly interested in climate change. In his paper, James Fleming examines Lyell's position on climatic change in geological and historical times, and explores the mutual influence of Lyell with James Croll who was a proponent of an astronomical theory of Ice ages. Clearly the period of Charles Lyell's active geological life was one when numerous important astronomical discoveries were being made and many theories being advanced about climate change. Fleming argues that Lyell was slow in modifying his views on climate change but only because he tempered his judgements with solid evidence gathered from the record of the rocks- a lesson we might all learn! It is clear from many of the contributions in this volume that labelling Lyell simply as a uniformitarianist who did not entertain catastrophes was not correct. Baker argues that working scientists are prone to misconceptions as to the relationship of philosophy to science. The 'new catastrophism' that Baker proposes is rooted in firm geological observation. Finally, in this section, Lyell Professor John Mather relates the historical development of hydrogeology in Britain through the nineteenth century, a subject of passing interest to Charles Lyell which was advanced in his day by geologists who needed practical solutions to locating groundwater supplies to support the growing industrialization of the nation. Lyell recognized that rainwater percolated through the ground to issue forth as springs at the junction of permeable and impermeable strata, and was interested in this as an Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 96 PART 2 aspect of the Earth's surface processes. But it was really only in the latter half of the century that the science of hydrogeology was established and hydrogeological maps were published. Derek J. Blundell Andrew C. Scott Downloaded from http://sp.lyellcollection.org/ by guest on September 27, 2021 Lyell's Principles of Geology: foundations of sedimentology M. R. LEEDER School of Earth Sciences, University of Leeds, Leeds LS2 9JT, West Yorkshire, UK Abstract: This chapter examines the extensive arguments Lyell brought to bear on the interpretation of sedimentary rocks through the operation of 'present causes' in the first Edition of Principles of Geology (1830-1833). A case is made inter alia for Lyell, rather than Sorby, being the true originator of sedimentology and basin analysis, amongst much else of course. Lyell had a special interest in Earth surface processes, and the effects of tectonics and climate on them, because he saw that the evidence is firmly written in the sedimentary products of observable events. His own explanations for the sedimentary and geomorphic processes of erosion and deposition were acutely sensible: he analysed (in today's parlance) river avulsions, controls on delta morphology, oceanic brine pools, cross stratification, confluence bars, boundary layers, hydraulic geometry, debris flows, sediment budgets, alluvial basin architecture, and clinoforms. Much of Sorby's work in some of these areas must have been inspired by his reading of the Principles. Lyell was occasionally too much guided by theory, as in the famous sophistry of his 1830 analysis (in the first edition) of the sedimentary and geomorphological evidence for Holocene Fenno-Scandinavian uplift. His willingness in subsequent editions of Principles to abandon such firmly held views in the light of empirical and personally collected field evidence to the contrary presages his momentous decision to throw his weight behind Darwin's natural selection theories some 30 years later. Lyell was not so rigidly an anti-catastrophist and inductionist as is commonly made out. His writings make very clear his ability to state bold theories. For example, his discussions of climatic change and his concept of the 'great year' were outstandingly incisive, holistic and original. They include the role of land-sea interactions, ocean currents and precessional orbital cycles. He even considered the probablity that continents and oceans changed position, albeit by vertical movements. The motive for all this came from observations he and others had made on the distribution of Cenozoic molluscs and the need for some general global cooling to explain these. He included in his actualism all manner of extreme (but not 'catastrophic') events, for example earthquakes and volcanic eruptions. He was also willing to consider (but then rejected) the possibility of catastrophes, most obviously in his discussion in the seventh edition of Principles (1846) of the possible 'lake-burst' of Lake Superior into the headwaters of the Mississippi. One feels he would have welcomed probability theory and the development of magnitude/frequency analysis, and that he would have laughed at any modern description of himself as the 'father of uniformitarianism'. It is tempting to view Charles Lyell as a remote Kennedy, who, according to his biographer (Sutton geological figure of only historical interest, with 1980, p. 301), during his distinguished tenure as little relevance today. The great work of his early Chair at Leeds (1946-1967), used to read through years, the first edition of Principles of Geology Principles before the beginning of each new acad- (Lyell 1830-1833), can thus be seen as a museum emic year to give himself the necessary inspiration item in the pantheon of early geological literature, for teaching. Nowadays the wide availability of the along with James Hutton's Theory of the Earth and first edition of Principles of Geology, via the William Smith's Geological Map of England and facsimile University of Chicago reprint, enables us Wales. This view is wrong, because geology is a all to confirm the essential modernity of much of special science in that much depends upon the Lyell's geological logic. Principles is an eternal primacy of field observations. Lyell was an acute stream from which we can all drink and refresh observer of Earth surface features and processes ourselves periodically. That the stream is a deep and the use of these in the interpretation of rocks. one, more than 1400 pages in total, is somewhat We can all relate to geologists of any age through off-putting but the majority of Lyell's views on their field observations; this stress on the empirical sedimentary topics are to be found concentrated in basis of geology is Lyell's hallmark, although, as volume 1, published in 1830.