Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204

Alain Godard on the NW Highlands of : present relevance for long-term landscape evolution studies Alain Godard sur les hautes terres de l’Écosse du Nord-Ouest : pertinence actuelle pour les études d’évolution du relief à long terme

David Jarman*

Abstract Godard’s seminal 1965 thesis is revisited as a landmark amongst regional geomorphological studies of Scotland and older uplands gen- erally, for its omnivorous powers of acute observation, for its rare grasp of structural and , and for its comprehensive synthesis of landshaping factors. While this vast work extended to the coasts, the , and , the revisit focuses on the upland areas of the NW Highlands. Factors which may have hindered its assimilation and follow-through in the coun- try of study and in anglophone geomorphology are explored. These include obvious and fundamental scientific differences – French regional and synthetic versus British process and thematic at a time of paradigm change away from Davisian denudation chronology – and more subtle cultural barriers, notably its exogenous status in the land of Hutton and Lyell, its non-translation into English, and its at times eye-catchingly expressive idiom and argumentativeness. These stylistic, linguistic, and editorial barriers illustrate the difficul- ties and opportunities in disseminating important concepts in transnational geoscience. While its lack of methodological originality can be criticised, the scope for emulating the author’s eye for landscape, understanding of , and passion to interpret their interac- tion is promoted. Godard’s magnum opus is today most noted for its highly detailed tracing of exhumed and extant surfaces. It remains relevant and instructive as the study of long-term landscape evolution undergoes a renaissance in Britain. Godard’s ideas and observations are assessed as platforms for future research on several themes which are reviving in the anglophone world: the large-scale efficacity of glacial erosion; drainage networks and watershed migration; etch-planation processes; passive-margin tectonics; and the possible roots of the paleic relief in the Caledonian orogeny. Key words: A. Godard, , erosion surfaces, watersheds, etch-planation, glacial efficacity, landscape evolution.

Résumé La thèse magistrale d’A. Godard (1965) est revisitée ici en tant que mine d’informations et matrice conceptuelle pour les études de géo- morphologie régionale tant sur l’Écosse que sur les massifs anciens en général. Cette thèse sert aussi de matériau pour dresser un portrait des capacités hors pair d’observation de son auteur, sa maîtrise exceptionnelle de la géomorphologie structurale et climatique, et son art pour la synthèse des facteurs qui ont donné forme au paysage. Face à un tel monument, le présent article se restreint à l’exa- men des Hautes Terres du nord-ouest de l’Écosse, et donc élude cet autre vaste domaine de l’ouvrage concernant les côtes et les îles Hébrides et Orcades. Les facteurs qui ont entravé la postérité des travaux de Godard au sein de la géomorphologie anglophone sont examinés. Ces derniers concernent des différences de culture scientifique évidentes mais fondamentales, notamment le régionalisme et le penchant français pour la synthèse contre l’accent sur les processus et le penchant thématique en Grande-Bretagne, à une époque charnière (1965) où s’opérait un changement de paradigme historique vers la process geomorphology au détriment de la denudation chronology davisienne. On évoquera aussi toutefois des barrières culturelles plus subtiles, comme le statut d’étranger sinon d’intrus dans la patrie de Hutton et Lyell, l’absence de traduction en anglais de l’ouvrage, et un style d’écriture et d’argumentation quelque peu désuet aux yeux de la nouvelle géographie scientifique. Ces barrières stylistiques, linguistiques et éditoriales soulignent des pro- blèmes récurrents dans la dissémination transnationale d’idées scientifiques. Bien qu’on puisse rester critique à l’égard d’un certain manque d’originalité méthodologique chez Godard, son sens du paysage, sa compréhension de la géologie et sa passion pour inter- préter leurs interactions n’ont fait que peu d’émules parmi ses homologues britanniques. Lorsqu’il est mentionné dans la littérature, le magnum opus de Godard demeure essentiellement célébré pour ses levés topographiques extrêmement détaillés des surfaces d’éro- sion, exhumées ou non. Il est toutefois instructif que l’étude de l’évolution du paysage à long terme subisse actuellement une

* Landform Research, Ross-shire, Scotland. E-mail: [email protected] David Jarman

renaissance en Grande-Bretagne. Dans cette perspective et dans le contexte d’une bibliographie actualisée sur l’Écosse, on réévalue ici la qualité des analyses de Godard et leur rôle de ferment pour des recherches futures sur quelques thèmes devenus récemment à la mode en géomorphologie britannique comme l’efficacité à long terme de l’érosion glaciaire, les conséquences morphologiques des pro- cessus d’altération, les réseaux hydrographiques et la migration des lignes de partage des eaux, la tectonique des marges continentales passives, et les traces de paléoreliefs hérités de l’orogenèse calédonienne. Mots clés : A. Godard, Écosse, surfaces d’érosion, réseau hydrographique, altération différentielle, efficacité des glaciers, évolution du paysage.

Version française abrégée focalisation sur les processus, Godard restait ancré dans une approche française régionaliste, employant des La thèse d’A. Godard, publiée en 1965, est peut-être la ten- méthodes encore limitées aux observations visuelles, à l’in- tative la plus monumentale jamais réalisée de produire en terprétation des cartes et aux analyses géologiques de solitaire le tableau géomorphologique d’une vaste région des routine. Affronter un si gros volume était donc une tâche Îles britanniques (fig. 1). Elle est fondée sur des travaux de décourageante, même si, comme ce fut le cas pour le présent terrain et des observations de grande envergure, et elle abou- auteur, les dividendes se sont avérées considérables à tit à une ample synthèse de facteurs aussi diversifiés que la condition d’y consacrer une lecture attentive. Cet effort a géologie ancienne, l’érosion tertiaire, et les glaciations qua- permis de révéler l’intérêt de détenir toutes les conclusions ternaires et leurs conséquences. Cet article se focalise sur d’une campagne de recherches contenues dans une seule l’évolution du paysage à long terme dans la partie non insu- source bibliographique, au lieu d’être éparpillées entre plu- laire des Hautes Terres du nord-ouest d’Écosse, c’est-à-dire sieurs articles comme c’est trop systématiquement le cas en les Highlands. On éludera donc le travail sur les côtes, sur Grande Bretagne. les archipels des Orcades et des Hébrides, et sur la Province L’actualité de Godard quarante ans après la parution de Volcanique Tertiaire, reprises depuis dans la thèse de Le sa thèse est examinée sous cinq rubriques : les surfaces Cœur (1994), ainsi que ses vues d’ensemble climatiques et d’érosion (y compris l’altération différentielle) ; l’évolution hydrographiques et ses abondantes analyses pétrologiques et du paysage à long terme (notamment les origines du relief sédimentologiques. paléique) ; l’inefficacité et la sélectivité de l’érosion gla- Il est inhabituel pour des géomorphologues étrangers de ciaire ; la migration des lignes de partage des eaux sous mener des programmes de recherche en Grande Bretagne, et l’effet de l’englacement ; et les limites des glaces (y compris on déplorera ici que l’absence de fertilisation croisée entre l’insignifiance des dépôts glaciaires et des processus post- écoles de pensée nationales, ainsi que l’attrait pour la glaciaires durant l’Holocène). On cite encore Godard au- recherche dans des régions plus éloignées et plus presti- jourd’hui comme l’auteur le plus crédible en ce qui concer- gieuses, soient à terme nuisibles à la discipline et ses ne l’analyse des surfaces d’érosion en Écosse, en grand protagonistes. En dépit d’une large ignorance du détail des partie en raison de ses levés topographiques remarquable- travaux de Godard par la communauté écossaise des ment détaillés et généralement valides des surfaces d’éro- sciences de la Terre, les aspects plus accessibles de son tra- sion, exhumées ou non. Ses cinq surfaces « tertiaires » vail demeurent malgré tout reconnus en Écosse (Sissons, comprennent une « surface écossaise » étendue, avec son 1976a ; Hall, 1991 ; Hall et Bishop, 2002), notamment ses « knick brutal » caractéristique ; et une « surface inter- levés topographiques des surfaces d’érosion. Néanmoins, médiaire », plus ancienne, qui indique un soulèvement en beaucoup de ses idées plus générales et la plupart de ses dôme. La gamme d’altitudes varie d’une région à l’autre, observations perspicaces sont restés dans l’ombre, et sans mais des surfaces définissent dans l’ensemble un système en presque aucune postérité en Grande Bretagne. escalier avec des niveaux à 800–1 000 m, 650–750 m, Certes, pour que la science reçoive quelque écho, elle doit 400–600 m, 180–300 m et 90–180 m. Au-delà des simplistes se rendre compréhensible, doit être communiquée avec com- sommets concordants davisiens, Godard utilise ces corréla- pétence et compter sur une large diffusion. Les raisons pour tions pour identifier des effets de déformation tectonique et lesquelles le travail de Godard n’est jamais entré au pan- des soulèvements saccadés. Ses levés topographiques n’ont théon de la géomorphologie anglophone en général sont toutefois pas encore été analysés par des techniques numé- examinées ici. On relèvera certaines évidences, notamment riques modernes. Ils soulèvent encore des interrogations en l’absence d’une traduction en anglais, pas même de maniè- ce qui concerne certains critères d’identification et de vali- re résumée, mais aussi son style littéraire et sa façon dation par des méthodes indépendantes. Il reste aussi à ex- engagée et combative d’aborder les problèmes (l’écriture pliquer pourquoi certaines surfaces sont en forme de ban- scientifique anglo-américaine étant censée être tranchée, quettes tandis que d’autres sont des vestiges de , à neutre et détachée). Plus fondamentalement, la thèse a été justifier les étendues parfois vastes qui séparent les vestiges publiée à une époque marquée en géographie physique par de ces surfaces fragmentées, et à identifier les processus im- un changement de paradigme scientifique majeur favorisant pliqués (par ex. fig. 4). Hormis les travaux de Le Cœur la géomorphologie dynamique. Au moment où la recherche (1994), essentiellement restreints à la province volcanique, anglophone entreprenait son aventure quantitative et sa les travaux français postérieurs à la thèse de Godard sur

178 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape l’altération différentielle n’ont pas encore fait l’objet d’une Deux autres taches aveugles chez Godard concernent le mise en application en Écosse continentale. fandelta du Ness, qui est unique en Grande Bretagne (Sis- La plus haute surface, ou « surface supérieure » selon sons, 1981), et l’importance des volumineux éboulements Godard, ne doit pas être confondue ou amalgamée avec les paraglaciaires de versants rocheux (Jarman, 2006). Son banquettes et plateaux intermédiaires. Elle comprend des penchant pour s’en prendre aux travaux des personnalités vestiges d’une surface ancienne conservée sur les sommets établies, telles que Bremner et Linton, plus par la force de onduleux de la topographie régionale. L’auteur omet de l’argumentation logique que par des démonstrations préciser cette distinction, et même s’il écarte la théorie de la appuyées sur des faits de terrain, a peut-être aussi nui à sa submersion mésozoïque suivie d’une table rase au Tertiaire, crédibilité auprès de lecteurs anglophones. Plusieurs de ses il n’explore pas le potentiel offert pour retracer une évolu- propres idées géomorphologiques, aussi brillantes soient tion subaérienne ininterrompue du socle calédonien allant elles, sont fondées davantage sur des intuitions et des extra- de l’orogénèse et sa surface infra-dévonienne à la surface polations que sur les analyses méticuleuses du type de celles actuelle des sommets (fig. 5). Godard est reconnu pour ses qui seront menées un peu plus tard par Sissons et son école. reconstructions de cette surface infra-dévonienne. Celles-ci Les méthodologies de Godard (notamment pour le levé divergent de celles proposées par Bremner (1942), et Go- topographique des surfaces d’érosion) et ses références aux dard la différencie d’autres topographies anciennes en voie travaux antérieurs sont de qualité inégale, et l’auteur se d’exhumation par l’érosion dans la même région. laisse parfois aller au débat d’opinion plus que ne l’autori- L’œil de Godard pour les palimpsestes paysagers est re- serait habituellement une démarche scientifique. Pour ces marquable. Ce talent inclut le Quaternaire, où l’auteur pré- défaillances de démarche et de style, il est instructif de com- figure des travaux britanniques ultérieurs en identifiant parer l’accueil général dans le monde anglophone de la l’héritage des glaciations pré-dévensiennes – notamment thèse de Godard à celui qu’a reçue celle de son collègue et les étages différents du développement des cirques. Le ami Rapp (1960). scepticisme de l’auteur en ce qui concerne l’efficacité de Le magnum opus de Godard gagne aussi à être examiné à l’érosion glaciaire est passé en grande partie inaperçu. Il travers les clés de relecture fournies par l’ouvrage sur identifie en Écosse des situations très répandues qui infir- « Les régions de socle », récapitulation précieuse de l’éco- ment cette idée reçue, et ses arguments invitent à réexami- le française dont il est devenu un chef de file (Godard et al., ner les parts respectives des érosions glaciaire et fluviale 1994, traduit en anglais en 2001). Cet ouvrage montre la dans le façonnement du relief actuel. Ses interprétations grande influence de sa thèse sur le cours des recherches quelque peu hérétiques à l’époque ont suggéré, avant francophones ailleurs dans le monde, en particulier dans les d’autres auteurs, que le concept d’érosion linéaire sélecti- plus vieilles chaînes de montagnes du monde. Cet ouvrage ve (Sugden, 1968) pouvait être mis à l’épreuve même dans fait aussi ressortir la presque totale absence de mise à jour l’ouest très découpé (fig. 6). de ses idées sur les Hautes Terres d’Écosse. Le travail de Le Godard exprime également un certain dédain vis-à-vis Cœur (1988) demeure l’exception, bien que cet auteur n’ait des dépôts quaternaires, insignifiants par leur volume et que peu publié. leur prégnance visuelle, et des processus holocènes dans le Pour récapituler les réussites de Godard, on doit retenir paysage actuel. Il n’éprouve presque aucun intérêt à retra- qu’il a été parmi les premiers à identifier : les paléo-nuna- cer les limites des dernières avancées, mineures, des taks (et donc les anciennes limites supérieures de la calotte glaciers dévensiens. Ceci s’inscrit en contrepoint de la foca- glaciaire écossaise) ; les paysages en palimpseste (quater- lisation sans doute excessive sur ces vestiges glaciaires et naires mais aussi beaucoup plus anciens) ; les vestiges périglaciaires qu’affectionnent les géomorphologues bri- d’une haute surface pré-glaciaire assez vallonnée, et enfin tanniques. Ceci n’a pas empêché Godard d’avoir été le les déplacements systématiques des principales lignes de premier à détecter des « paléo-nunataks » dans les Hautes partages des eaux. Il est le premier à avoir défié les ortho- Terres d’Écosse continentale et d’en déduire, à partir de doxies régnantes sur la prédominance de l’érosion glaciaire leur distribution, la configuration générale de la calotte dans les massifs montagneux, et sur l’enfouissement des glaciaire durant son maximum d’extension. Cette observa- racines des montagnes calédoniennes sous une épaisse cou- tion pionnière n’a été exploitée que beaucoup plus tard par verture de sédiments mésozoïques. Il a développé enfin une Ballantyne et al. (1998). cartographie presque exhaustive des surfaces d’érosion ter- Tour à tour audacieux et réservé, Godard est le premier à tiaires, devenue un modèle de référence pour ce qui avoir effectué le levé topographique du déplacement vers concerne les reliefs à multiples niveaux étagés. Sa démarche l’est de la principale ligne de partage des eaux. Sauf à ses holiste et son art de la synthèse restent presque sans équi- terminaisons extrêmes, il se limite prudemment aux sous- valent parmi les études régionales existantes sur l’évolution bassins dont la capture paraît la plus évidente (fig. 7). Il du paysage, surtout dans les Îles britanniques. Ces qualités intègre les effets de l’effondrement tectonique du Minch, ont ouvert la voie à de nombreux travaux sur les interac- mais ne prend pas en considération ses conséquences sur tions entre géologie, tectonique et climat en France sans l’évolution du réseau hydrographique régional. Il reconnaît toutefois que le prototype écossais ait bénéficié par la suite (après Linton, 1949) l’ouverture de nombreuses brèches par des progrès réalisés ailleurs. les glaces, sans toutefois en aborder l’âge, l’étendue ou Nous concluons sur un appel à revenir, grâce aux travaux l’impact possible des cas principaux. méconnus de Godard, sur l’étude géomorphologique des

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 179 David Jarman

Hautes Terres d’Écosse continentale en tant que microcosme (etch-planation), origins of the paleic relief (tectonics), gla- de l’évolution du relief à long terme dans les régions de cial inefficacity (offshore deposits), watershed reconstruc- socle, voire des régions de marge passive aux latitudes tion and glacial breaching, and ice limits (trimlines, cosmo- moyennes. À partir de cette réévaluation, et dans la pers- genic nuclide dating); (iii) to convey the distinctive flavour pective de recherches futures, on peut dresser une liste de of his thesis, with examples of his ability to unite geology thèmes scientifiques à la fois stimulants et controversés, tous and landscape, of his powers of landform observation, of his en germe dans la thèse de Godard mais restés sans réponse occasional blindspots and minor lapses, and of his hyperbo- définitive : l’altération différentielle et ses conséquences lic and combative style; (iv) to explore the effects of style sur le relief ; les surfaces d’érosion et leur façonnement en and language as both bridges and barriers in comprehending fonction de niveaux de base régionaux mais aussi locaux ; and communicating seminal geoscience; (v) to suggest that formes à contrôle structural et formes d’érosion ; soulève- Godard’s initial reception and present standing in Britain ment et basculement au début du Cénozoïque et leurs causes have been inhibited by numerous factors, not only stylistic géodynamiques ; la submersion Mésozoïque, sa réalité, son and linguistic, but including paradigm change, and funda- étendue et son rôle, à réévaluer grâce à des études de ther- mental differences in purpose between anglophone and mochronologie basse température ; les origines de l’actuel- continental geomorphology; (vi) to regret the lack of pursuit le surface des sommets, et sa dérivation à partir de la dis- of Godard’s findings, and in the five themes to explore how cordance calédonienne (Caledonian Unconformity) ; l’évo- he might have refined them had a challenging peer-group lution des réseaux hydrographiques et la migration des milieu existed; (vii) to discuss the rarity of ‘exogenous’ re- lignes de partage sur le long terme (y compris le rôle de la search by foreign geomorphologists in Britain, and to argue tectonique) ; la disposition actuelle et l’altitude absolue des for greater cross-fertilisation between national schools, for hautes surfaces ; les impacts relatifs de l’érosion céno- re-exploration of well-studied areas as a test bed for new zoïque (fluviale) et quaternaire (glaciaire), y compris dans thinking, and for a return to ‘real geomorphology’ seeking to les captures de drainage ; enfin les effetsde l’isostasie sur le comprehend whole landscapes and disseminate findings to long terme. wider audiences. Since this revisit is the fruit of a belated encounter with the actual work, and has evolved from an Aims and approach amazed personal hommage à Godard, the story unfolds more readily if these post-rationalised aims are taken in ap- A. Godard’s thesis, published in 1965, is perhaps the most proximately the reverse order. substantial solo attempt at a comprehensive landscape evo- lution study of a large region in Britain, grounded in Context: exogenous research wide-ranging original fieldwork and observations, but in Britain achieving a broad synthesis of factors from ancient geology through Tertiary erosion to and its Godard’s thesis is rare as a major exogenous, non-British aftermath. This reappraisal focuses on the mountainous core based contribution to the study of Scottish, and indeed Bri- of his study area, the NW Highlands of Scotland, and skips tish, geomorphology. Why should this be, and what do we over his work on the coasts, the Orkney and Hebridean lose thereby? There seem to be both scientific and cultural archipelagoes, and the Tertiary Volcanic Province, as well as barriers to ‘foreign’ research – echoing differences in fields his climatic, hydrographic, petrological, and sedimentologi- as diverse as philosophy, literary studies, and energy policy. cal analyses. Since his findings have never been published The ‘political geography’ of geomorphological research has in summary form (apart from a few precursor papers on spe- certain territorial and colonial tendencies, which allied to cific aspects), those unfamiliar with the tome itself will find national differences in mindset and language can both shar- a partial introduction to it in what follows. pen its focus and inhibit dissemination and cross-fertilisa- In revisiting a work over 40 years old, it would be egre- tion. In Europe, countries with strong schools of geomor- gious to criticise it as though it were published yesterday. It phology such as Britain, France, Germany, Poland, or Swe- was not notably innovative in method or concept; its streng- den seem to monopolise their home territories. Conversely, th was to apply the entire armoury of available techniques some countries with abundant geomorphic interest can at- and thinking to a given area, with the insight of a great tract researchers from many quarters, as in Spain, Greece, structural geomorphologist possessed of a remarkable eye Norway, and Iceland. And where a geomorphic entity is po- for landscape at all scales. From today’s perspective, it litically sub-divided, there can be a lack of synthetic spatial stands as a landmark broadly free of gross error or crass overview in the corpus of research, notably in the Alps, misinterpretations. where mappings of ice limits (e.g., school of Schlüchter, The aims of this revisit are thus: (i) to identify Godard’s Bern) or mass movements (e.g., schools of Crosta in Milan; principal lasting achievements in upland geomorphology Brückl in Vienna) tend to stay within national boundaries; in (drawn together in the concluding evaluation); (ii) to exami- the Scandes, where studies of pre-glacial land surfaces deal ne five of his main upland themes for their present relevan- mainly with the Swedish side of the border (Stockholm ce, as a spur to a renaissance in landscape evolution studies school) and would benefit from extending over the whole in Britain, and in the light of subsequent ideas or more re- range (A. Stroeven, pers. comm., 2006); and indeed in the cently acquired data (bracketed): Tertiary planation surfaces , where efforts such as Clayton and Shamoon

180 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

(1999) viewing as a whole impress by their ra- French tradition, even though it went well beyond mere des- rity and still omit Ireland. cription and cataloguing, with a carefully-integrated International research programmes tend to seek charisma- synthesis; (ii) it had the misfortune to appear after the hey- tic locations where processes are active, change is day of British physical geographies, just as the quantitative measurable, and results from exemplary sites and studies and methodological revolutions were transforming geomor- can be scaled up across broad zones. Geomorphologically, phology; (iii) it was constructed out of reams of relatively the British Isles are small, inactive and rather trivial, com- anecdotal material, organised on a Guide Michelin basis prising a messy collage of landscape types in a transitional rather than thematically as his Table des Matières proclaims climatic context (neither sub-tropical nor arctic). Lacking and apparently collected as opportunities arose rather than wider relevance, they are thus generally the preserve of to meet pre-specified research objectives (such simple local-interest workers, although the French school (notably honesty being out of fashion here); (iv) much of the data on Battiau-Queney) has taken a valuable neighbourly interest which maps and conclusions were based was not presented, in the SW peninsula and southern Ireland, integrating the and many interesting points lacked illustration (e.g., the sur- Variscan fragments of Armorica (Godard et al., 1994, 2001). viving rock-cut meanders, the géoflexure transversale, and Within Scotland, the paucity of exogenous research can the steep belt–flat belt transition instanced below); (v) the be illustrated from one comprehensive bibliography (Gor- index was confined to main themes, making it impossible to don and , 1993), which for Quaternary geomor- track down specific observations; (vi) his style was verbose, phology cites only six authors of non-UK origins and re- declamatory, enthusiastic, and egotistical – all capital search base including Godard. Of these, Agassiz (1841) was offences to the younger generation who wanted to leave exceptional as an invited paradigm-changer, whose findings behind the self-indulgent travelogue manner and make geo- were assiduously published and promoted in English by his morphology a respectable science; even a paragon of the hosts. By contrast, Louis (1934) and Sölch (1936) were the new virtue admits to being mocked for including the uns- first to identify wholesale glacial breaching of the main wa- cientific term ‘remarkable’ in a title (Sissons, 1976b; tersheds; published only in German, they were known to Sissons, pers. comm.); (vii) he took a confrontational stan- Linton and thence Godard, although not cited in his biblio- ce, robustly challenging leading workers in the area; yet he graphy. Since then, only Godard’s might have been a semi- demanded ‘observable facts’ when it suited him, while nal exogenous contribution, had it been more thoroughly making sweeping assertions (e.g., ‘it cannot be denied’, ‘it read and widely disseminated over here. Had we enjoyed a is beyond all reasonable doubt’) whenever he lacked them; stronger infusion of the ‘French approach’ to geomorpholo- (viii) above all, his work was only available in French, and gy, we might now have a better appreciation of Scotland’s to read it properly required a great commitment of time, and landscape evolution, which currently lags far behind the much wrestling with his (or that language’s) wondrously state of knowledge of Scotland’s geology, paleogeography, elaborate syntax and rich vocabulary. glacial and eustatic history, and process geomorphology A litmus test of its initial penetration is offered by Sissons (Trewin, 2002). (1976a), who cites Godard in respect of the pre-Devonian And as to why Godard chose this particular region for his land surface, Tertiary planation surfaces and their warping, ‘exogenous research’, his own career review (Godard, 2006) the supposed offshore drowned river network, and the distri- simply acknowledges his mentor at Nancy, Guilcher, for bution of cirque elevations. It may be significant that these steering him to the British Isles. He describes Scotland are all subjects of Godard’s principal figures; however, his affectionately as his ‘école de terrain’ even above the Mas- mapping of a preglacial drainage system and watershed dis- sif Central (p. 14), but neither in the original work nor in placements is omitted. Since then, the lack of follow-up subsequent publications does he place it in the context of research to test and expand upon his ideas has prevented the comparator regions or develop its relevance for crystalline emergence of an informed critical debate. Indeed only one of basements or passive continental margins. his 18 full-doctorate students has addressed Scotland: Le Cœur (1994) applies updated approaches including an etch- Godard (1965): reception and basin typology to the Inner Hebrides, but again most of this present standing in Britain work remains unpublished. Today, in speaking to Scottish geomorphologists one ge- The published PhD is an extraordinary achievement, com- nerally finds ‘Godard’ regarded as little more than a vast piled over ten years (Rapp, 1960, below), and tackling a footnote to history, if not as grotesque an outpouring as wide range of geomorphological issues over an extensive Charlesworth’s 2300 pages (1957); they might agree that it (25,000 km2) and diverse area covering the NW Highlands, had some interesting material and ideas, but regret that these Hebrides, and Orkney (fig. 1). It is difficult to grasp the were mostly lost in non-translation; they would only refer to depth of this commitment, when British PhDs have always it fleetingly if at all for any contemporary relevance. In geo- been much shorter in timescale and more restricted in area logical circles, Godard is neither cited in Trewin (2002) nor or subject matter. even mentioned in a well-referenced wider-audience book However, it seems likely that the value of this magnum on the geohistory of his study area (Rider, 2005). A current opus to British workers was diminished because: (i) it was study modelling the Caledonian and compa- unashamedly a classic regional physical geography in the ring it with present day topography across Scot-

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 181 David Jarman

Fig. 1 Ð Northwest Scotland, showing locations, features, and lithologies referred to in the text. The NW Highlands lie to the north of the Great Glen. 1: internal (etch?) basins; 2: Tertiary Volca- nic Province; 3: Old Red ; 4: Moine thrust; 5: Strahconon fault; 6: Quoich line; 7: Kyle- railway; 8: preserved meanders (KL: Kyle RheaÐLoch Long; LH: Loch Hourn; OY: river Oykell); LD: Loch Duich; SC: strath Croe. Fig. 1 Ð Le Nord-Ouest de l’Écosse, avec toponymes, sites et lithologies mentionnés dans le texte. 1 : bassin interne (alvéole d’altération différentielle ?) ; 2 : province volcanique tertiaire ; 3 : Vieux grès rouge ; 4 : chevauchement de Moine ; 5 : faille de Strath- conon ; 6 : Quoich line ; 7 : voie ferrée de Kyle à Dingwall ; 8 : méandres conservés (KL : Kyle RheaÐLoch Long ; LH : Loch Hourn ; OY : rivière Oykell) ; LD : Loch Duich ; SC : strath Croe.

182 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape land was not aware of Godard’s mapping of it (D. Macdo- This is neither an attribute unique to Godard, nor the last nald, pers. comm. 2006). gasp of a former, more expansive era. One might say his Nevertheless, the most recent overview of Scotland’s style is ‘very French’, except that Linton and his predeces- landscape evolution (Hall and Bishop, 2002) still refers to sors also cultivated an eloquent and magisterial manner. But Godard (including three of his precursor papers) to eviden- in recent years, and with respect to crisply entertaining ce some fundamentals: three Neogene stages of uplift, authors such as Stoddart or Goudie, France may have beco- including warping of erosion surfaces (also citing Le Cœur, me a last bastion of the principle that original science can be 1988); exhumed sub-Torridonian, sub-Devonian and sub- written as literature, with a personal stamp and conviction, Triassic surfaces; the importance of deep (chemical) with a passion to engage, communicate, and persuade. For in pre-Quaternary relief development; the exis- the present writer to take delight as well as profit from rea- tence of of position (as against those of resistance ding (also in French) a thesis on a subject as esoteric as Les or exhumation). And Ballantyne (2007) still attributes to versants du Spitsberg (André, 1993) attests to a continuing Godard the first detailed and substantially sound descrip- tradition. Even in translation, sparks of creative language tions of the massive landslips along the Tertiary Volcanic can still fly (e.g., Lageat and Gunnell, 2001). Province escarpments (even citing his splendid description A further great merit of Godard is that his entire corpus of of as ‘cette topographie anarchique’). research on NW Scotland is comprised in a single work. For Since Godard’s career in geomorphology is founded on the general customer, this is invaluable, by contrast with the this epic work, the reasons why he never published his fin- present absurdity of splitting PhD findings into multiple dings in English (conscious decision, lack of time, transla- papers, with all the drawbacks of access, duplication, incon- tion difficulties, or inability to find a publisher?) would be sistency, and lack of a unifying train of thought that this of interest. Even his ten satellite papers on Scotland are all entails. By contrast, in History and Archaeology it is still but one in French journals (e.g., Godard 1957, 1961). In re- quite common to write a single book based on the thesis. It trospect. Godard (2006) extols the scenery of Scotland, but would help geoscience disseminate its endeavours and reach is silent as to the reception of his thesis in Britain, and its a wider audience if authors were encouraged to take time to lasting value or influence; perhaps it is difficult to maintain collect their thoughts, to hone their communication skills, enthusiasm for an area when there is virtually no ‘feedback’ and even to deploy language as imaginative as his. Indeed, from it on one’s findings. an updated ‘Godard’ with its grand sweep, vivid examples, and pungent style would make a valuable quarry for a pro- Comprehending Godard: gramme on the scenery of Scotland. communicating geoscience In now proceeding to explore the thesis, references in brackets thus (p. 145; fig. 42), etc. are to pages and illus- These questions of style and language are not trivial, trations in Godard (1965); locations mentioned are shown because they mediate the transmission of scientific informa- on fig. 1. tion. First impressions count for a great deal, and obstacles to ready comprehension deter pursuit. The shape of the land: uniting Since a survey of those who have read Godard is imprac- geology and physical geography tical, a personal account must illustrate the vicissitudes. After long awareness of Godard as an exotic reference to do More than any other work known to the writer, Godard’s with planation surfaces, the writer borrowed a copy in 2002, thesis addresses the question ‘why is this land shaped like out of idle curiosity. With a typically basic command of this?’ – perhaps reflecting his early architectural enthusiasm French, it took several weeks to become acquainted with for ‘la géométrie des formes’ (Godard, 2006). He tackles the even that half of Godard dealing with the more mountainous question with unflagging passion, while stopping just short areas; many revisits were required to digest it and explore of the sentimentality of the mere topographer. He operates further. Few can afford such quixotic dedication, which was on two levels simultaneously – always looking for the big sustained largely by the verve with which Godard writes. picture, the grand generalisation or verdict, but always alert Even so, the writer’s initial scribbled reactions were mixed: to the reality of specific sites, whether they support the over- ‘persevering through the flowery prose morasse… self- view or stand out as exceptions to be accounted for. He is indulgent regional descriptive tradition… an absorbing aware of processes, but his fieldwork rarely attempts to wealth of detailed observation and insight’ albeit this was measure them; he is interested in the issue of rates of ero- ‘frustrating as he hardly touches the main mountain areas – sion, but in the absence of data of his own or in the literature which he admits were too difficult of access’. But reactions he is reduced to airy speculation. Given his diligence in such as ‘language delightful, refreshing enthusiasm, won- quantifying many elements (pebble shape and size, corrie derful selection of words’ attest to his compelling style and elevation, clay minerals) it is intriguing to imagine how he rich vocabulary (see samples of his phraseology in the ori- might have utilised the techniques that have since become ginal French italicised throughout the paper). Had the same available. issues been written up in the arid, anonymous, condensed Above all, Godard brings to this question the training of a manner of present-day ‘mid-Atlantic’ geoscience, it would geologist combined with the perspective of a physical geo- quite probably have deterred such diligence. grapher. This parallels a British tradition going back to the

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Geikies and manifest in textbooks such as Holmes and surface bevelled across it, while the flat-belt terrain rises Sparks. Sadly, this has fallen victim to specialisation. There appreciably to the main watershed where it zig-zags west- has been no leading landscape geomorphologist in Scotland east across the Great Glen (see fig. 7). He suggests that the in recent times with strong geological roots, and vice versa. more subdued relief in the flat-belt must be attributed to an Thus there is no standard work which integrates the two: intermediate planation advancing more readily but incom- Sissons (1967) published his still-unsurpassed Evolution of pletely across it (p. 324) – geological factors and Scotland’s Scenery at too early a stage in his career; while time-constrained geomorphological processes both contri- packed with insights into aspects of the landscape, it is not buting to the current landscape. grounded in geology, his opening chapter on Rocks and Relief being derivative; Sissons (1976a) is updated but slim- Godard’s powers of geomorphological mer; and unlike Godard, he factorises rather than integrates observation and relevance today the landscape. The Geology of Scotland over its several edi- tions (Trewin, 2002) makes no pretence of considering the Godard is exceptional in his ability to characterise the dif- surface expression of bedrock and structure. A recent work ferent mountain groups; for example, to describe on Geology and Landscapes of Scotland aimed at a wider and its geologically disparate neighbours as les témoins audience (Gillen, 2003) is excellent on individual features, d’un ancien « rempart » bien démantelé facing the north as befits a geologist, but covers the shaping of the entire coast (p. 109) brings them into refreshing perspective. Grampian mountain range in a paragraph. Countless landscape insights, large and small, are buried in Godard’s instinct for geology and landscape is omnivo- Godard’s text. Some are exhumed in the great final synthe- rous, for example: (i) the shapes of the -Coigach sis, but many are all too easily missed: (i) he discerns ‘le inselbergs are interpreted with exceptional closeness, not relief appalachien’ in present landscapes as disparate as least to disprove their glacial origin. Intriguingly, he attri- volcanic Ardnamurchan, the environs of Gairloch, and iso- butes the larger extent of Quinag (as an inselgebirge) to a lated Eday in Orkney; he applies it with more interpretative lower frequency than usual of faults and dykes in the Lewi- force to the ORS-buried quartzite ridges of Caithness. This sian basement on which it stands, plus its position above a unexpected analogue does not appear in Sissons (1967) or hollow in the pre-Torridonian surface (p. 145); (ii) Seana Gillen (2003), but may not be original (p. 178, 550, 566); Bhraigh and the Freevater group are recognised as mon- (ii) he is able to portray what we are accustomed to regard tagnes massives… succèdent brusquement vers le Nord… as some of the most rugged wild land in Britain (coastal des plateaux assez réguliers d’altitude médiocre (p. 116). , Morar, Ardgour) as a paysage plus aéré et moins He interprets this bold step of 400 m in identical Moine sauvage than the high and deeply dissected just lithology as a géoflexure transversale from to Dor- inland. He attributes this to advancing planation creating an noch. It fronts a 20 km gap between the and intermediate plateau landscape which was then subjected to Assynt massifs, which is the most substantial differential glacial erosion (p. 300). It takes Godard to show ‘doorway’ (Rudberg, 1992) in the main mountain axis of the us a possible wood for the trees; (iii) he draws attention to Highlands (see fig. 7). Yet although noticed by Peach et al. sequences of rock-cut meanders in the Oykell (1912) it has attracted little attention, and is hard to explain (p. 293), on a grander scale at Loch Long–Kyle Rhea by fluvial or glacial ‘breaching’; (iii) he asks why the moun- (p. 355), and more doubtfully in the course of Loch Hourn tains of North Harris and the low plateau of South Lewis are (p. 612), which he suggests must predate glaciation. These cut in the same gneiss, finds no petrological differences, and may be isolated survivals, or not even mature river products, infers a tectonic role (p. 226); (iv) the Inchbae internal basin but they still demand explanation: for example, above is conventionally associated with differential erosion in the sinuous Loch Long there is in fact a straight-sided glacial Inchbae augen-gneiss, and Hall (1991) proposes similar trough at 200 m asl (above sea level); (iv) he identifies lithological explanations for the basins of NE Scotland. But nunataks above the ice sheet such as and Ben Godard points out that the basin ‘englobes’ the igneous More Assynt from their pointed, frost-shattered summits, intrusion (p. 317), and is etched equally across Moinian contrasting with the surfaces plus lourdes rabotées par les psammites and the weaker Old Red Sandstone (ORS) depo- glaciers elsewhere (p. 604). sits (see fig. 5). Even so, he notes that the augen-gneiss is While large swathes of Godard might now be passed over especially resistant to linear incision, yet vulnerable to che- as Victorian in their eclectic observations and opportunistic mical weathering, thus favouring etching and inverted measurements, including countless petrological and fabric topography; however his tectonic and erosion-surface expla- analyses, there is a core which addresses major issues that nations for the adjacent Carn Chuinneag augen-gneiss are still relevant and far from being resolved. It might be forming distinctive summits are less convincing; (v) the thought that Scotland, as a small country where geoscience marked contrast between the high, dissected mountains of originated and with a strong research capacity in geomor- the Western Highlands and the lower-key terrain separating phology, has been studied to death, but this very familiarity them from the Great Glen is conventionally attributed to the makes Scotland an excellent test bed for new ideas. Regret- steep-dipping–flat-lying transition within the Moine schists tably the direction of effort by funding bodies to exotic (the ‘Quoich Line’). Godard notes this, but observes that the locations in recent decades leaves many of the challenges steep-belt nevertheless has traces of an undulating highest raised by Godard still to be pursued. There are some signs

184 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape of reawakening interest in the landscape evolution of Scot- the summit accordances best seen by eye, although the al- land after long neglect (e.g., Bishop et al., 2005), and five most exactly equal altitudinal heights of some groups of themes from Godard are here explored as a prompt to reap- peaks can dangerously reinforce such impressions. While praisal with the benefit of contemporary techniques and the rival marine and sub-aerial theories could apply to both mindsets. kinds, presumably only the latter is amenable to interpreta- tion as late-stage Davisian peneplanation. Theme 1: Tertiary planation surfaces It now seems remarkable that as late as 1966 leading wor- kers such as George and Jardine could still advocate exten- Godard is most often cited for his identification of a sive marine planation to explain the summit surface. Godard sequence of five Tertiary planation surfaces (e.g., Gordon finds their Achille’s heel in the requirement for absolute ho- and Sutherland, 1993; Hall and Bishop, 2002). This may be rizontality. Thus he lampoons Hollingworth’s statistical cor- his best-known contribution because it is prominent on a relations as requiring to postulate l’absence de tout gauchis- fold-out map (his Carte VI), and is accessibly summarised sement des niveaux (p. 572); while Godard is thinking main- in the text (p. 572–587). It is a readily-grasped concept – in ly of regional warping, we can add local tectonic displace- today’s media-speak, it has ‘sound-bite’ quality. The vali- ments and differential glacio-isostatic recovery as negating dity of Godard’s system of surfaces is today generally numerical accordances (affection for which still lingers: accepted, even though his and subsequent interpretations e.g., ‘the elevated surfaces... represented by plateaux and of their origins remain unconvincing (A. Hall, pers. comm., coincident summits’, Trewin and Rollin, 2002). 2006); this is still one of the most vexed issues in Scottish Godard emphasises that his surfaces are not level, locally geomorphology. or regionally, although he is not the first to avoid this trap, To place Godard in his context, two kinds of surface must following with scant acknowledgement Geikie, Peach and be distinguished: the erosional bench, most apparent from Horne, and Fleet (cf. Sissons, 1967): (i) his fragmentary sur- mapwork especially when miles wide and fragmented, and face supérieure is traced across the highest plateaux and just below residual peaks such as Foina- ven. It is allowed to undulate consi- derably, providing it remains calme (fig. 2). West of it displays a bombement to attain 800–1000 m asl; it declines to 600 m in the far north, but southwards it is lost to ex- treme dissection; (ii) his not-quite- a-surface hauts paliers d’érosion et fragments perchés de haute surface comprise sparsely scattered inter- fluves and benches at 650–750 m asl (fig. 3); (iii) his ‘magnificently conserved’ surface intermédiaire is best displayed on Tertiary Volcanic Province and Caledonian granite plateau fragments. It rises from 400 m asl to a central 600 m, suggesting domed uplift; (iv) his well-known surface écossaise is characterised Fig. 2 Ð Sgurr nan Conbhairean (1105 m), one of the higher peaks in the NW Highlands, a pyramide résiduelle assez lourde (p. 325). Note the tip of its smooth cone, which probably by le knick brutal at its inland li- rose higher before truncation by the deep cirque behind the left shoulder. The mits. It slopes gently (3-4° is cited comprises a distinct monadnock swelling steeply from the broad bench at 950Ð1000 m well at one point), and lies within a band seen to its right. The summit and shoulders are probably below the main periglacial trimline, but of 200-300 m asl, which in a dis- appear only lightly glaciated. Godard did not map his surface supérieure in this area. View east concerting nod to the ‘flat-earth’ from A’ Chràlaig (1120 m), a similar monadnock with scantier traces of paleic relief (photograph: D. Jarman). tendency he finds echoed all round the British Isles (p. 581). Endearin- Fig. 2 Ð Sgurr nan Conbhairean (1 105 m), une Ç pyramide résiduelle assez lourde È gly, he admits to so terming it to (p. 325) et l’un des plus hauts sommets dans les Hautes Terres du Nord-Ouest. Noter la pointe émoussée de son sommet, dont la hauteur était probablement encore plus importante avoid having to assign any age or avant d’être réduite par la morsure profonde du cirque en arrière de l’épaulement situé sur la mode of origin to it (p. 579); confu- gauche. La surface paléique comporte un monadnock qui se dresse nettement au-dessus de la singly he also calls it the aplanisse- large banquette à 950–1 000 m, visible sur la droite. Le sommet et les épaulements se situent ment écossais; (v) his lowest niveau probablement au-dessous de la limite supérieure des glaces, mais ne semblent avoir subi que pliocène around the coasts and up de légères modifications par l’érosion glaciaire. Godard n’a pas effectué le levé topographique de sa Ç surface supérieure » dans cette région. Vers l’est, on observe d’A’ Chràlaig (1 120 m), valley benches is the most extensive, un monadnock semblable avec des vestiges plus réduits du relief paléïque (cliché de l’auteur). embracing a heterogenous collection

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Fig. 3 Ð Extensive upland erosion sur- faces in partly mapped by Godard. A: viewed from Diebidale Ridge (691 m) looking west to Beinn Dearg, the northernmost summit in Scotland over 1050 m asl. Foreground: was not identified by Godard as a surface, but identical to hauts paliers. Middle ground: mapped as hauts paliers d’érosion. Beyond them, slightly lower uplands (not well seen) are mapped as surface intermédiaire. Right skyline: Carn Bàn plateau 4x10 km, boldly swelling summits 845/822 m mapped as surface supérieure, other selected benches and outliers as hauts paliers. Left skyline: mountains of the Beinn Dearg massif, eight fragments mapped as surfa- ce supérieure despite summits ranging between 927 and 1084 m (most fragments sub-kilometric, but Am Faochagach partly seen extreme left is one of Godard’s three largest at 3x2 km). The entire ensemble forms a coherent, smoothly hilly preglacial landscape, the three mapped surfaces merging with few pronounced breaks other than glacial troughs (the narrow axial trough of Gleann MorÐGleann Beag is unseen beyond the middle ground, and is ~300 m deep). B: viewed from Dunan Liath (691 m) looking north to Bodach Beag (822 m) and Càrn Alladale. Foreground: hauts paliers above Gleann Mòr glacial trough. Middle ground: broad ridge des- cending gently eastward, mapped as small fragments of hauts paliers (left) and surfa- ce intermédiaire (right edge), but with no obvious distinction. Skyline: small widely separated fragments of surface supérieu- re, hauts paliers, and surface intermédiaire from left to right. Most of skyline not assi- gned to any surface (Photography: Jarman). Fig. 3 Ð Hautes surfaces d’érosion de grande étendue en Easter Ross, partiellement cartographiées par Godard. A : vue vers l’ouest depuis Diebidale Ridge (691 m). On aperçoit Beinn Dearg, le sommet (à 1 050 m d’altitude) le plus septentrional de l’Écosse. Le premier plan, quoique non identifié par Godard comme une surface, est identique au second plan, identifié comme un haut palier d’érosion. Derriè- re ces niveaux, les terrains à peine en contrebas sont identifiés par Godard comme « surface intermédiaire È, bien que la distinction soit peu perceptible. Sur l’horizon, à droite : plateau de Carn Bàn (4 x 10 km), sommets proéminents à 845/822 m identifiés par Godard comme appartenant à la « surface supérieure », et autres bancs et pics isolés identifiés comme « hauts paliers È. Sur l’horizon, à gauche : mon- tagnes du massif de Beinn Dearg, huit fragments identifiés comme « surface supérieure È malgré l’altitude des sommets entre 927 et 1 084 m (la plupart des fragments font moins d’un kilomètre carré, sauf Am Faochagach, visible à l’extrême gauche, l’un des trois plus grands de Godard : 3 x 2 km). L’ensemble forme un paysage préglaciaire lisse et vallonné, mais cohérent. Les trois surfaces identifiées se recoupent sans ruptures topographiques marquées en dehors des brèches formées par le creusement glaciaire (l’étroite dépression linéai- re de Gleann Mor–Gleann Beag, qui n’est pas visible au-delà du second plan, fait ~300 m de profondeur). B : vue vers le nord depuis Dunan Liath (691 m) en direction de Bodach Beag (822 m) et Càrn Alladale. Au premier plan, « hauts palier » au-dessus de la dépression glaciai- re de Gleann Mòr. Au second plan, large crête descendant vers l’est, identifiée comme un ensemble de petits fragments des Ç hauts paliers È (gauche) et de Ç surface intermédiaire » (bord droit), mais sans critère de distinction très nets. Sur l’horizon, de droite à gauche, petits frag- ments espacés de « surface supérieure È, Ç hauts paliers È et Ç surface intermédiaire È. La majeure partie de la ligne d’horizon n’est attribuée à aucune surface (clichés de l’auteur).

of features between 90-180 m asl, and can often slope by very little hard or datable evidence to go on. Unfortunately, that height range (p. 584). he gives neither the criteria employed in his identification Godard is excellent in conveying the character of these and mapping of these surfaces, nor worked examples of how surfaces as they are encountered, and their relations to litho- they are to be distinguished in any sequence. This would logy and structure, post-formational tectonics, and correlati- have been especially important given that their absolute ve deposits. He perceptively infers climatic environments height ranges merge (Sissons, 1976a). His method relies on and processes, and estimates their descending ages from une très large mesure au patient travail de reconnaissance these inferences and from cross-cutting relations, all with sur le terrain (p. 572), with mapwork, sections, and air pho-

186 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape tos only utilised secondarily. We have to take on trust that pates that le véritable knick, found where the surface écos- les grands plans inclinés can be seen in the field, but ‘not on saise terminates brutalement against slopes as steep as 25°, even the best maps’. Yet when his Carte VI is taken into hills is vulnerable to the criticism ‘how has it survived glacia- such as Easter Ross where broad surfaces seem well deve- tion?’, and responds with a teasingly seductive straw man: loped (fig. 3), admiration of his perceptiveness is tempered ‘so it must be an early Quaternary marine planation cliff by bewilderment. Especially at the upper levels, countless line then’ (p. 582). This proposition is then sledgehamme- rather uniformly distributed fragments have been selected red on six counts, all didactically compelling, but the origi- when much larger areas would seem equally qualified; in nal question still begs more discussion (see section on gla- the not atypical area of fig. 3, only 10% of the terrain is as- cial inefficacity below). signed to the upper three surfaces, and entire interfluves are overlooked while adjacent ones are embraced. Etch planation? Godard assigns all these surfaces to the Cenozoic. The hauts paliers, for example, cut the Paleogene Volcanics, but Indeed Godard leaves the processes by which his surfaces quite how they can be traced with confidence to a single extend rather vague – a longstanding criticism of the sub- base-level event effective from Skye to the east coast is aerialists (Sissons, 1976a). His researches just precede the unclear. Contrarily, although the surface intermédiaire best advent of ‘etch-planation’, which Hall (1991) identifies as displays deformation (p. 573), he cannot reconstruct its iso- the key process in humid sub-tropical Tertiary erosion in the hypses in the Volcanics or adjacent west coast because of Highlands, and much of what he describes anticipates this later tectonic movements. model. Thus he recognises internal basins (cuvettes, for The five surfaces have essential if unacknowledged dif- which he later coined the term ‘alvéoles’) as part of erosion ferences of character. One (intermédiaire) is mainly a surfaces, with evacuation of weathered debris via main bevelled plateau. One (écossaise) is a broad pediment rivers; he frequently notes the adjustment of relief to geolo- below a degraded scarp with its characteristic ‘knick’. Two gy, which is fundamental to etching, although he observes (pliocène; hauts paliers) include both plateau fragments bevelling across the grain just as often; and he sees his sur- and benches, but without mention of ‘knicks’ backing face écossaise in particular as best explained by des them. And the surface supérieure is a rolling landscape processus de planation latérale dans un materiel inégale- with occasional monadnocks. But Godard does not consi- ment altéré... sous climat de savane ou semi-aride (p. 582). der different geneses (e.g., plateaux from downwearing, Of course, earlier planation surfaces are likely to become benches from base-levelling) nor indeed whether the upper progressively more modified, but it is unclear whether his two or even three plateau surfaces could be related. Above identification procedures allow for this. about 600 m asl, they share similar smooth signatures in air The opportunity is not taken in Godard et al. (2001) to photos, and could all be integrated into a single preglacial retro-apply the etch-planation concept to Scotland, although land surface of greater overall relief (e.g., fig. 3 and fig. 4); a not entirely convincing small example in similar glaciated indeed Gjessing (1967) made such a suggestion, with schistose terrain in Labrador is illustrated in its fig. 3.3. One contemporaneous development of paleic forms at all eleva- problem is that Godard’s simple notion of un soulèvement tions adjusting to local (p. 109). Interestingly, Le saccadé or staged uplift (p. 573), triggering successive ero- Cœur (1994) is also a ‘lumper’ rather than a ‘splitter’ of sion-surface ramifications, requires all surface elements to erosion surfaces. be attributable to a specific marine base-level stillstand. But With hindsight, Godard’s key concept is a ‘staircase’ of since planation can presumably propagate from any resistant Cenozoic surfaces, a previsioning of the ‘multi-storeyed rock barrier or tectonic break creating a local base-level, landscapes in passive margins’ (Godard et al., 2001). But there must in practice be an increasingly anarchic overlap- although the ‘treads’ of this staircase occupy about half i.e. ping of locally and regionally originated surfaces over time. the terrain (at least at lower levels), it is not clear what sta- Thus Godard’s cuvettes cannot be assumed to have similar tus is assigned to the other half – the ‘white spaces’ on Carte dates and modes of origin – basins such as Atholl, Spean, VI. These intervening strips are too pervasive to be simply Naver (p. 279), or Shin (p. 283) (fig. 1) are at different ele- the ‘risers’ between sub-tropical pediments, and they can vations, drain to four structurally separate sea areas, and hardly be attributed to blurring by glaciation. The risers have differing geological enclosures. It would be intriguing illustrated by Peulvast in Norway and Lageat in South Afri- to have a Godardian structural geomorphologist analyse a ca (in Godard et al., 2001) appear relatively abrupt: basin with several possible controls such as Monar (fig. 4) crucially, Godard does not give any cross-sections relating with the benefit of etch-theory. Based on clues provided by his surfaces (fig. 4a). Have these strips evolved coevally fig. 4, possible factors in basin development in these head- with the surfaces at their feet, or do they represent degrada- waters of the east-flowing River Farrar might include any tion of original scarp-like risers, encroaching into the combination of structural factors: the basin could be (i) a surfaces above, and if so over what timescales? vestige of an ancient NE–SW intramontane basin, (ii) be- The survival of plateau fragments and mountain tops can hind a more durable band in steep Moinian metasediments – be understood within the framework of selective glacial although most of the basin is in uniform psammites except erosion, but it is less obvious how staircase elements might for pelites north of the Ling and Monar gorges, or (iii) behind survive, especially at lower levels. Indeed Godard antici- a barrier either tectonically uplifted or (more feasibly, becau-

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 187 David Jarman

A

Fig. 4 Ð The Monar internal basin, , immediately east of the main Highland watershed, a testing ground for etch pro- cesses and erosion surfaces. For location see fig. 1. A: form of Monar basin with surrounding fragments of Godard’s three highest surfaces and additional paleic relief. 1: Monar basin outlined by the 457 m (1500 feet) contour; 2: main Highlands watershed; 3: inferred pre-glacial watershed; 4: glacial breaches; 5: glacio-fluvial incision; 6: Monar gorge; 7: Strathconon fault; 8: gulls-wing upland drainage. The sections confirm Godard’s identification of ‘multi-storey relief’ surrounding the basin, which displays marked asymmetry in Section A. Note that valley widths at the 457 m contour, just 10 km east of the watershed, are: 1.5 km for the Meig and the Orrin, 2 km for the and the Affric, and 4 km for the Monar. B: view of the Monar basin looking NNE approximately along line of Section A from below point 1089 to Maoile Lunn- daidh plateau (point 1007), showing the surface supérieure (SS) grading smoothly into the hauts paliers (HP), and more pronounced surface intermédiaire (SI) bench in middle ground (Photography: Jarman). Fig. 4 Ð Le bassin intérieur de Monar, Wester Ross, juste à l’est de la ligne principale de partage des eaux : un laboratoire naturel pour mettre en regard processus d’altération différentielle et surfaces d’érosion (localisation : fig. 1). A : contours du bassin avec frag-

188 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

the surface écossaise, but curiously is not mapped as such, whereas ex- tensive areas in the Ling basin to the west and in east-flowing basins fur- ther north are. It is still not very clear how etch- planation is supposed to operate in the roots of a passive-margin moun- tain range. Indeed Thomas (1989) treats the ‘etched plain’ as merely one expression of relief differentia- tion and elimination by dynamic etch processes when he writes: ‘it re- mains a problem to reconcile this long-term trend towards a more dif- ferentiated land surface with the claim for both regional and local pla- ments des trois surfaces les plus élevées de Godard et ajout du relief paléique. 1 : bassin de nation levels’ (p. 261). The processes Monar souligné par l’isohypse 457 m (1 500 pieds) ; 2 : ligne de partage des eaux des High- by which extensive low-relief etch- lands ; 3 : ligne de partage des eaux pré-glaciaire hypothétique ; 4 : trouées glaciaires ; 5 : surfaces are elaborated in the High- incision (fluvio-)glaciaire ; 6 : gorge de Monar ; 7 : gorge de Strathconon ; 8 : réseau de vallées lands are difficult to envisage given: dendritique. Les coupes confirment l’identification effectuée par Godard de « relief à niveaux (i) long-term tectonic buoyancy multiples È autour du bassin, avec une asymétrie marquée illustrée sur la coupe A. Noter que les largeurs des vallées au niveau de l’isohypse 457 m, à peine 10 km à l’est de la ligne de par- continually tending to decouple the tage des eaux, sont de 1,5 km pour la Meig et l’Orrin, 2 km pour la Cannich et l’Affric, et 4 km terrain from marine base level, with pour la Monar. B : vue vers le NNE du bassin de Monar à peu près dans l’alignement de la reincisions/rebevellings destroying coupe A, du point 1089 jusqu’au plateau de Maoile Lunndaidh (point 1007). Ce paysage montre earlier surfaces and operating across la Ç surface supérieure È se raccordant aux Ç hauts paliers », et un banc marqué de la « sur- terrain which has had little time for face intermédiaire » au second plan (cliché de l’auteur). etch-weathering; (ii) sod-forming vegetation cover (evolved in the se this would also explain the anomalous far-eastern position early Tertiary) and a generally warm, moist climate greatly of the Strathfarrar Range) laterally displaced along the Stra- inhibiting wash processes and thus pediment formation; thconon Fault (a major Caledonian lineament). To these and, as a corollary, (iii) fluvial export of deep-weathered structural factors we may add (iv) the erosional exploitation material being restricted to narrow corridors of incision plus of any enhanced etch-weathering within the basin by fluvial limited zones of significant lowering by solution, leaving dissection by the Farrar drainage system behind the barrier wide interfluves of inactive relief across successive phases created by (i)–(iii); (v) a rejuvenation of the west coast drai- of uplift. nage promoting a fluvial breach of the main watershed and Godard et al. (2001) give examples of etch-planation ran- a transient capture of part or all of the basin by the short and ging in scale from kilometric alveolate relief in the Massif steep River Ling; and/or (vi) glacial breaching at several Central to continental on ancient cratons, but the processes points across the main watershed, which enabled a broad ice- capable of eroding extensive surfaces in post-orogenic ti- stream to flow west (notably through the broad Ling ‘door- mescales in locations such as Scotland remain elusive; et- way’) and glacial reduction of already narrowed or lowered ching is not invoked by Peulvast (1987) in the Scandes, al- interfluves. Overdeepening of the Monar trough by 50 m though Lidmar-Bergström and Näslund (2002) identify it could have been achieved by east and/or west-flowing ice. around their fringes and possibly in the lowest level of the Note the narrow Monar Gorge, situated in unusually com- paleic relief. With justifiable exasperation, A. Hall (pers. plex topography, and only ~1 km wide (Section B). It is not comm., 2006) remarks that ‘The Scottish Highlands are not obviously a glacial breach in origin as are the adjacent gaps a good location in which to study erosion surfaces because and the narrow passes to the west. It may be a pre-glacial in- glaciation and recent uplift have removed correlative depo- cision maintaining the continuity of the Monar-Farrar river, sits on land. The serious student of long-term landform de- as drainage orientations confirm, perhaps accentuated by gla- velopment should perhaps go elsewhere’. Perhaps in pursuit cifluvial action. Erosion surfaces mapped at small scale by of suitable analogues for Scotland? Godard and considerably extended from field, map, and air photo evidence suggest a hilly paleic relief, with smooth Planation surfaces become spurs down to 700 m asl. The sections imply incision of the Monar Gorge into a ridge as young as the surface intermé- When it comes to Les problèmes d’ensemble, one senses diaire facets, and elaboration of the Monar Basin at its ex- that Godard’s heart lies in geological influences on scenery pense. The floor of the Monar basin is at the 250–300 m asl rather than in the planation issue, and that he may have been level as recognised by Godard in the mountain interior for directed to pursue it by others (possibly his mentor, Guil-

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 189 David Jarman cher). Yet Godard et al. (2001) celebrate a ‘re-enchantment surface supérieure. This is not a new perception (Geikie re- with the erosion cycle’, and the Scottish Highlands are cited cognised a summit ‘tableland’) but Godard is the first to exa- for Godard’s ‘ample and compelling evidence... for the mine it minutely. Yet he is uncharacteristically deprecatory development of step-like erosion surfaces’ (p. 62). They about it, for although he maps scores of widespread frag- might also have noted that his surface supérieure bevels ments, he considers it would be aléatoire de les raccorder across lithologically-variable and uptilted metasediments, in entre eux (p. 300), especially south of the Kyle-Dingwall contrast to the selectively preserved/eroded Cambrian quart- railway line where they become réduits et plus douteux zite peaks, thus spanning one of the concluding issues set (Carte VI). They range in elevation from 750 m to 1150 m out by Lageat and Gunnell (2001) in their siliciclastic wea- asl, with considerable local variations. This surface should thering problem of climate versus geology. repay thorough remapping and testing with new techniques, Within Scotland, erosion surfaces remain rather passé. not least since it is the most likely to have survived glacial Sissons (1967) endorsed planation for the new geomorpho- modification; a sample area around Monar suggests it could logy, recognising Godard’s map as ‘by far the most detailed be considerably extended (fig. 4). In his reluctance to com- work on erosion surfaces in Scotland’. However, it has prehend this surface as a whole, and in bracketing it with the never been critically evaluated (cf. figs. 3 and 4), and has multi-storeyed Tertiary planation stages, Godard misses the lain dormant, no doubt because it is unconducive to precise possibility of tracing an evolution, however exiguous, from measurement, process verification, and objective proof. The the original shaping of the Highlands. advent of techniques such as Digital Elevation Models and LiDAR imagery ought to assist identification, although the Exhumed erosion surface comparators effort of Ringrose and Migoñ (1997) in a transect across the Central Highlands lacks conviction in the absence of Yet he provides a splendid explication of two ancient sur- Godardian groundtruthing. faces now being exhumed east and west of the Moine Thrust By contrast, studies in Scandinavia are well respectively, interpreting them as real buried landscapes advanced: interestingly, Lidmar-Bergström and Näslund with significant slopes and corrugations, although he maps (2002) describe ‘characteristic landscape types formed by them very conservatively as lambeaux (‘tatters’) along their etching and planation’, which vary in their hilliness and outcrops (his Carte V): prédévonienne, which he notes was mode of evolution in much the same way as Godard failed identified by Bremner (1942); and infratorridonienne, to distinguish. The tectonics provoking these paleosurfaces which he accepts has long been known to unspecified géo- remain contentious, with some contributors to Doré et al. graphes (in fact at least as far back as Geikie in 1888), with (2002) rejecting Godardian ‘soulèvement saccadé’ after an the classic hilly unconformity exposed on being sans initial Paleocene uplift, instead interpreting Tertiary base- doute la plus belle d’Écosse (p. 168). level changes as climatic/eustatic; elsewhere in the Godard observes that the basal breccias and conglome- Caledonides, doubt is now even being cast on any major rates burying the sub-Torridonian surface fossilisaient une Paleocene uplift event, as against long-persisting post-oro- topographie irrégulière sculptée dans le gneiss lewisien genic buoyancy (Nielsen et al., 2007). Scotland might bear (p. 564) without even noticing canyons 150–350 m deep comparable re-evaluation, although its smaller size and around Stoer (Stewart, 1972; Rider, 2005). Likewise, he lower elevation should make it rather less susceptible to tec- recognises that the ‘pre-Devonian surface’ on which the Old tonic/isostatic effects (S. Nielsen, pers. comm., 2006). Red Sandstone (ORS) accumulated was hilly, evidencing Godard’s analysis is, of course, predicated on a substantial valleys cut in Moine schists as deep as 300 m in the Inchbae and pulsed Tertiary uplift from low relief (Hall, 1991). Even area (p. 566; fig. 5). He is well aware that the ORS is the if this is challenged, the terrain patterns which Godard produit de la destruction des chaînes calédoniennes, but he sought to map do exist (fig. 3), and beg explanations which does not convey its essential difference from the Torridonian must surely be more generic than site-by-site geological sandstone: this was deposited on an ancient planation surfa- adaptations, tectonic variations, or drainage evolutions. The ce, latterly uplifted and dissected, whereas the ORS intervening ‘white spaces’ between Godard’s surface frag- comprises ‘the molasse deposits of the emerging Caledonian ments, including some extensive planar versants (e.g., mountains’ whose extant basal members were variously fig. 4a), remind us that it is the totality of the ensemble of ‘alluvial fans at the foot of actively moving fault scarps’ and slopes that has to be understood, not just the most readily ‘deposited on a mountainous landscape’ (Mykura, 1991). It extracted elements. is curious that Godard seems unable to visualise a diachro- nous sub-Devonian surface encapsulating a ‘moving Theme 2: Origins of the paleic relief moment’ in the shaping of the Caledonian mountains, as the products of their rapid erosion lapped steadily higher up It is now generally recognised that the present main ele- their still-rising slopes. ments of the Highlands are the eroded roots of the Caledo- The landscape evolution significance of this sub-Devo- nian orogeny (Hall, 1991), but the trajectory is poorly-un- nian surface, or ‘Caledonian unconformity’, is intriguing. derstood and contentious. Thus perhaps the most challen- By definition the ORS deposits can never have covered the ging of Godard’s surfaces in landscape evolution terms as summits or higher ridges (e.g., fig. 5), and the subsequent the ‘paleic relief’ and parent form for all that follows is his stripping of ORS only reveals the ‘final form’ of specific

190 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape lower parts of the mountains at snapshot moments in the try of the eastern Grampians, there are few areas which could orogeny. Thus no trace of the ‘final form’ of the summit be called flat in the / sense, with Sugden’s relief at the end of the orogeny can have been preserved. (1968) summit surface having a local amplitude of 150 m. The possibility of continuous sub-aerial evolution from Smooth ‘gulls-wing’ fluvial valleys unrelated to present local emergent Caledonide mountainscape to present paleic base levels can be found in the upper reaches both here and relief appears not to have occurred to Godard or earlier in the glacially-dissected western Highlands (e.g., fig. 4), workers. where tiny pre-Quaternary surface remnants display quite pronounced relief (fig. 2). Evolutionary descent from the sub-Devonian What Godard does not quite do is to make the evolutiona- surface to the present summit surface ry connection between the Devonian relief of the buried mountain footslopes (the exhumed lambeaux) and his surfa- It had long been thought that the proto-range had been re- ce supérieure, which he relates entirely to Tertiary duced to low relief, submerged, planated, buried in Mesozoic upwarping (‘in all probability éogène (= Paleogene) or deposits, and rejuvenated in the early Tertiary as a tabula later’, p. 573), although he does concede that since it has no rasa on which a new drainage system was inscribed. The no- datable deposits on it and bevels no Tertiary Volcanics, this tion of a complete chalk cover (Linton, 1951) was under at- remains open to debate (p. 576). Godard may have blinke- tack by George and others as Godard wrote, paving the way red himself in his anxiety to rebut Bremner’s attempts to for his devastating coup de grâce (see below). Even so, the trace surviving Devonian surfaces with minimal Tertiary Godard-Sissons generation still built their accounts from Ter- modification (p. 567). Thus Bremner instances the sharp tiary foundations, and the shaping of the range remains ridge of Scaraben buried in ORS, which Godard belittles as contentious. On the one hand, N. Trewin (pers. comm., 2006) a special case of resistant quartzite lithology, but might well considers that submergence during the late-Cretaceous eus- be a freshly-eroded minor Caledonide crest overwhelmed by tatic high may have been very extensive; apatite fission-track deposits from surrounding higher ridges, now outstanding analyses (AFTA) suggest deep burial to many geologists by topographic inversion. Bremner also suggests that the (A. Hall, pers. comm., 2006), although these results have puzzling tract of intermediate relief between the Great Glen been challenged; and thick sediment sequences in offshore and the Western Highlands (the ‘flat belt’ mentioned above) basins suggest pulses of uplift and erosion, but their asso- is an exhumed Devonian surface, which emerges from ciation with upland relief elimination is not proven. On the beneath ORS fringes at The Aird and Meallfuarvonie. It other hand, the paleogeographies in Trewin (2002) indicate seems not unreasonable to detect a ghost of a mountain fore- substantial Highland land-masses since the Devonian and land in the structure here, but Godard dismisses it because especially throughout the Cretaceous (Harker, 2002, figs. he finds two Tertiary planation surfaces inscribed on it. 12.4-12.9 therein), a consensus reflected in a wider-audien- provides an exceptionally well-constrained ce work on Scottish mountainscapes (Goodenough, 2006). opportunity for reconstruction (fig. 5). Bremner recognises Even if Cretaceous marine transgressions were very exten- it as a Caledonian mountain ridge separating two basins of sive, their local planations and thin deposits would only extant ORS deposition, Inchbae and Cromarty. Given the have been superficial interruptions, soon erased, with the alignment of this range parallel to the Moine and Sgurr Beag underlying hydrography quickly reasserting itself. Tectonic Thrusts, and further ORS outliers on the same alignment ex- events not fully known to Godard have had considerably tending NE for 100 km (fig. 1), it is intriguing to envisage greater influence on the shape of the landmass, notably the here a vestige of the fold-parallel ridges and intramontane end-Variscan opening of , and the Paleogene valleys typical of alpine ranges. But Godard dismisses the opening of the Atlantic, with its associated vulcanism brie- idea that the present steep planar NW slope of Ben Wyvis is fly burying proximal upland areas. However, the structural literally an exhumed Devonian mountain side on narrow controls on the north-western seaboard and the extent of technical grounds, missing the larger point. Yet surely his post-rifting uplift and possible tilting remain speculative. own lambeaux on either side of Ben Wyvis (his Planche V) Bearing in mind that the landward ORS is a terrestrial sys- must scope its original height as an alpine massif with at tem of deposits, it is thus arguable that the extant Caledoni- least 3000 m relief, assuming minimal subsequent tectonic de metamorphic basement has never been submarinated movements (see section on fig. 5)? The notional subdivision since its Ordovician/Silurian emergence; and that the present of the range reflects the present relief, and the tendency of paleic relief is the end-state of a near-continuous process of valley spacing in the Highlands and metasedimentary Alps to sub-aerial erosion, albeit of varying modes and paces, from be around 8 km rather than 15 km. A summit height of the Devonian until now. Godard’s summit surface fragments around 3300 m, i.e., 1300 m above the present summit, turns suggest evolution from a mountain range of alpine character out to be broadly compatible with latest estimates inferring to a rolling upland, with fluvial encroachments after succes- average removal of 1.5 km of overburden in the last 300 Ma sive or sustained uplift never eliminating their cores. Deep (A. Hall, pers. comm.). Sources of conglomerate are from weathering mantles, and the longevity of the Grampian divi- Peach et al. (1912) as acknowledged by Godard. They record de (fig. 7), suggest that this dissected upland may well have abundant augen-gneiss in the Strath Rannoch outliers, but become rather stable in general form, if not of course in ab- none SE of Wyvis. They inferred that the intrusions had been solute height and shape. Even in the present ‘plateau’ coun- buried in ORS before deposition of extant conglomerates on

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 191 David Jarman

Section

192 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

Fig. 5 Ð Ben Wyvis and Inchbae, Central Ross-shire. For locations see fig. 1. The Inchbae cuvette or internal basin is not confined to the augen-gneiss outcrop, but encompasses three lithologies. Ben Wyvis is the only high massif framed by Old Red (ORS) outcrops. The cross-section suggests how they might assist in reconstructing its scale soon after the close of the Caledonian orogeny (geology interpo- lated from British Geological Survey sections in vicinity). 1: Old Red Sandstone (on basal unconformity), with M (Middle) and L (Lower; the contact at SE flank is Emsian); 2: breccia and conglomerate; 3: breccia and conglomerate along fringes; 4: sources of conglomerate after Peach et al. (1912), with figures indicating maximum clast dimension in metres; 5: augengneiss (AG) with unroofing domes (IB: Inchbae; CC: Carn Chuineag, occurs north of section); 6: Moinian schist (SCH), with psammite (top) and pelite (bottom); 7: Torridonian and Cambrian pebbles (T+C), occurring only in Middle ORS and in outrcops currently 50 km to the west; 8: preglacial land surface including maximum relief (dashed lines) NE of section (Ben Wyvis range only; 772 may also be a preglacial remnant); 9: Meall a’ Ghrianain outlier (772) and Meall nam Mullach (SCH:AG); 10: faults, thrusts; 11: Caledonide major sinistral strike-slip fault (SC: Strathconon fault; SG: fault). The theoretical maxi- mum elevation envelopes apply strength equilibrium slopes of 20¡ (the lowest residual friction angle generally found in schists, allowing for significant erosion of the orogenic pile towards conditional stability), and 30¡ (a median figure attainable during the period of rapid upbuilding). The peak friction angle of 40¡ in schists would theoretically yield a summit of 6800 m above present sea level, but while locally sustainable, syn-orogenic erosion would prevent literal attainment. The notional profile of the Wyvis range is centred above the reconstructed preglacial whaleback mountain, which in turn reflects the greater resistance of the Glenfinnan Group pelites. The high SE face is adopted from Trewin and Thirlwall (2002, fig. 8.14 therein), which indicates ‘high mountains with deeply incised valleys (and) alluvial fans’. Fig. 5 Ð Ben Wyvis et la cuvette d’Inchbae, Ross-shire central (voir fig. 1 pour la localisation). La cuvette d’Inchbae n’est pas confinée à l’affleurement de gneiss œillé et met en jeu trois lithologies différentes. Le massif de Ben Wyvis est le seul qui soit encadré par des affleure- ments de Vieux grès rouge. La coupe suggère comment ces grès peuvent servir à la reconstruction de l’étendue du massif après la fin de l’orogenèse calédonienne (géologie interpolée des coupes voisines levées par le British Geological Survey). 1 : Vieux grès rouge (sur dis- cordance basale), avec distinction entre étages M (Moyen) et L (Inférieur ; le contact au flanc SE est Emsien) ; 2 : brèches et conglomérats ; 3 : brèches et conglomérats sur les bordures ; 4 : sources des conglomérats selon Peach et al. (1912), avec chiffres indiquant la dimension maximale des clastes en mètres ; 5 : gneiss œillé (AG) affleurant en dôme (IB : Inchbae ; CC : Carn Chuineag localisé au nord de la coupe) ; 6 : schiste moinien (SCH), avec psammite (demi-caisson du haut) et pélite (demi-caisson du bas) ; 7 : galets Torridoniens et Cambriens (T+C), présents seulement dans le Vieux grès rouge moyen et dans des affleurements actuellement présents 50 km plus à l’ouest ; 8 : sur- face topographique pré-glaciaire avec enveloppe topographique maximum (lignes tiretées) au NE de la coupe (seul le massif du Ben Wyvis est représenté ; la cote 772 est peut-être un résidu pré-glaciaire) ; 9 : buttes de Meall a’ Ghrianain (772) et Meall nam Mullach (SCH:AG) ; 10 : failles, chevauchements ; 11 : failles calédoniennes majeures à jeu décrochant sénestre (SC : faille de Strathconon ; SG : faille de Stra- thglass). Les enveloppes d’altitude maximum théorique de la chaîne calédonienne impliquent des pentes d’équilibre critiques de 20¡ (plus faible angle de friction résiduelle généralement rencontré dans les schistes, tenant compte de l’érosion considérable du prisme orogénique en équilibre stationnaire) à 30° (valeur médiane réalisable durant la période de construction rapide de l’orogène). Une valeur maximale de 40¡ sur schistes fournirait un sommet théorique de 6 800 m au-dessus du niveau actuel de la mer, mais cette altitude est irréaliste en raison de l’érosion syn-orogénique. Le profil hypothétique de la chaîne de Wyvis est centré sur la montagne pré-glaciaire reconstruite en forme de dos de baleine, qui reflète la forte résistance des métapélites du Groupe de Glenfinnan. La haute façade vers le SE est adoptée de Trewin et Thirlwall (2002, leur fig. 8.14), qui décrivent de Ç hautes montagnes avec des vallées profondément incisées… et des cônes alluviaux È. the SE, but since both flanks are now dated as Lower ORS, developed on a Paleogene tilted uplift, from a stepped se- a simpler reason would be that the intrusion roofs were lower quence in southern Norway where uplift and doming has than the proto-Wyvis crest (as sketched). Remarkably, they continued, all with inferred Mesozoic origins. They conclu- found frequent pebbles of Torridonian and Cambrian prove- de that ‘genetically interpreted landforms are important da- nance (nearest present outcrops ~50 km west, beyond the tasets in morphotectonic analyses, complementary to studies Moine Thrust) but only in the Middle ORS SE of Wyvis, sug- of the sedimentary record and thermotectonic evolution of gesting consequent southeasterly trunk drainage with early the bedrock’. It is high time to extend similar, comparative incision of major gorges across Caledonide axes, as com- investigations to Scotland, in which Godard’s pioneering monly seen in young orogens. They described the basal un- mapping of summit surface remnants, so cautiously under- conformity as ‘very uneven’ with local cliffs. Godard shows played by him, merits revisit, testing the probability that (his fig. 112) the Strath Rannoch outlier as filling/capping they are rather more extensive and the possibility of consi- two valleys/interfluves with sub-Devonian relief of 300 m. derably earlier ancestry. Clearly this reconstruction would be flawed if significant vertical tectonic displacements had occurred post-ORS de- Theme 3: Glacial inefficacity position, but this seems unlikely. The major Caledonide (NE–SW) fault movements framing this area have been pre- After a century of enthusiastic post-Agassiz pursuit of the dominantly lateral. Ben Wyvis is anomalously high for the new paradigm of Ice Age Scotland and its wholesale remo- eastern side of the NW Highlands, but this may be not unre- delling by glaciers, Godard (1961) is possibly the first to lated to the anomalous preservation of the ORS Strath Ran- seriously question their role (in Scotland if not in Scandina- noch outliers adjacent to it; as with the Strathfarrar Range via): leur efficacité globale a été trop souvent surestimée (fig. 4) it could result from ancient lateral displacement because glacial action has been applied to a relief already along transcurrent faults. profondément marqué par le dispositif structural (p. 7). He In Scandinavia the ‘paleic relief’ has been recognised for intuits this at every scale: (i) a roadcut in the supposedly over a century, with pre-Tertiary pedigree (Gjessing, 1967). scoured gneiss of NW Sutherland reveals 4.5 m of deeply Lidmar-Bergström and Näslund (2002) can distinguish a rotted bedrock (p. 134); where solid rock is exposed, the ice heavily-dissected summit surface in the northern Scandes, has ‘contented itself with polishing it’, although he reco-

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 193 David Jarman

are most pronounced where pregla- cial valleys were already most dee- ply incised, on the short descent to the west coast. Faults such as Stra- thconon are more influential than ice outflow direction in shaping glacial troughs. The Great Glen gabarit (template) is glacial, but the valley is Tertiary, with glaciers merely exag- gerating plateau vs. valley contrasts (p. 611). He approves of Tarr’s ana- logy with Alaska, with glaciers lo- sing their erosive powers when they Fig. 6 Ð A case for selective linear erosion by glaciers in the dissected Western Highlands, leave the valleys and spread over as suggested by schematic profiles along main watersheds. Profile (a) shows its classic lower ground, where preglacial fea- effects in the Eastern Highlands, with simple cirques, troughs and occasional sharply-incised tures survive widely. Le Cœur breaches. Profile (b) suggests that the scoured relief of the Western Highlands is merely a surfa- ce roughening of essentially similar selective erosion of deeper troughs, many of them breached (1994) endorses the predominance and cross-breached, but with much of the preglacial topography surviving with increasing intact- of structural and preglacial signa- ness at higher levels. 1: preglacial land surface remnants; 2: superficially scoured glacial tures over Quaternary processes, in topography; 3: background relief, including cross-breaches between main valleys (4). the igneous Inner Hebrides at least. Fig. 6 Ð Le cas de l’érosion linéaire sélective par les glaces dans les Hautes Terres de l’ouest, This iconoclasm has scarcely suggérée par les profils schématiques des principales lignes de partage des eaux. Le profil been noticed, e.g., not by Sissons (a) montre ses effets classiques dans les Hautes Terres de l’est, avec des cirques simples, des (1976a), possibly because once auges et d’occasionnelles brèches profondément incisées. Le profil (b) suggère que le relief récu- again Godard does not illustrate it. ré des Hautes Terres de l’ouest n’est que la version plus accidentée d’un paysage fondamentalement semblable à (a), avec des entailles d’érosion sélective plus profondes. La plu- It was a necessary corrective at the part des interfluves encadrants sont troués par des brèches de transfluence, mais les survivances time, but perhaps overegged. Lin- de topographies pré-glaciaires demeurent plus intactes vers les niveaux plus élevés du paysage. ton (1959) had grasped the extreme 1 : topographies pré-glaciaires résiduelles ; 2 : topographie glaciaire ayant subi un râclage superfi- contrasts between west and east in ciel ; 3 : topographie d’arrière-plan avec trouées de transfluence entre les vallées (4). the dissection of a once-uniform upland, which must reflect a signi- gnises that the gneiss lacks crush zones and faults to exploit ficant glacial contribution, while Haynes (1983) (p. 138); (ii) even in the mountains, the cirques of demonstrates the limited area of preglacial land surface sur- are found weak by comparison with those of the Lake Dis- viving at higher elevations in most of the Highlands. With trict (p. 138, here acknowledging Thompson); (iii) the the abundant data on offshore glacial deposits now available extreme relief of is contrasted with that just inland, and attributed to greater preglacial dissection of the coastal Fig. 7 Ð The main watershed of the NW Highlands, showing dis- mountains, exploited by glaciers where it suits their direc- placements from preglacial positions inferred by Godard (1965) tion of discharge (p. 183); (iv) the survival of incised and Jarman (2006). Note how the catchment area of the River Ness meanders in Strath Oykell is an example plus démonstratif is almost entirely intercepted by Loch Ness, rendering the ‘fan-delta’ de l’efficacité limitée du travail glaciaire (p. 293). at Inverness (see fig. 8) patently anomalous. 1: present main water- In the core mountain area of the Western Highlands, under sheds; 2: inferred pre-Quaternary watersheds (Jarman, 2005); 3a: watershed displacements according to Godard and author; 3b: dis- le travail glaciaire (p. 332) he catalogues the evidence for placements according to author; 3c: displacements according to incomplete glacial remodelling of a preglacial valley sys- Godard, doubtful; 4: Loch Linnhe river (Godard, doubtful); 5: steep tem, with gentle slopes (10-15° in Garry and Arkaig), lack belt/flat belt (S/F, Quoiche line);6: mountains in flat belt (750Ð950 m of truncated spurs or hanging valleys, the raccordement of asl); 7: river Ness catchment. tributaries, and oversteepening occurring only locally at the Fig. 7 Ð La ligne principale de partage des eaux des Hautes slope foot even in the most extreme 1000 m relief at the Terres du Nord-Ouest, montrant les déplacements des positions head of Loch Duich. Here on the west coast les formes typi- pré-glaciaires déduites par Godard (1965) et Jarman (2006). quement préglaciaires n’ont guère été modifiées par les Noter la manière dont le bassin hydrographique de la Ness est presque complètement intercepté par le Loch Ness, rendant de ce passages répétés de la glace (p. 356). fait anormal le fan-delta d’Inverness (v. fig. 8). 1 : principales lignes de In a masterly summary of les retouches… quaternaires partage des eaux actuelles ; 2 : lignes de partage des eaux pré-qua- (p. 603 – a splendidly dismissive phrase), Godard stresses ternaires hypothétiques (Jarman, 2005) ; 3a : déplacement de ligne that although the Highlands exemplify glaciated relief, this de partage des eaux selon Godard et l’auteur ; 3b : déplacement does not mean a radical transformation by ice. Even the im- selon l’auteur ; 3c : déplacement (discutable) selon Godard ; 4 : Loch Linnhe river (selon Godard, mais discutable) ; 5 : steep belt/flat belt pact of cirque erosion must not be exaggerated: there are few (SB/FB, Quoich line) ; 6 : reliefs montagneux de la flat belt arêtes resulting from cirques adossés (p. 609). Glacial troughs (750Ð950 m d’altitude) ; 7 : bassin versant de la rivière Ness.

194 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

(Clayton and Shamoon, 1999; Stoker and Bradwell, 2005), linear erosion’ in the eastern Grampian plateaux, while it would be interesting to see how Godard might reappraise ‘areal scouring’ is seen in the degraded ridges and knock- the total effect of this volume of glacial erosion in reshaping and-lochan terrain of the west. It is the latter which Godard the Highlands landscape. It is also notable that Lageat and is really challenging, whereas the former might be a power- Gunnell (2001) contrast Godardian glacial cosmetics in ful ‘hidden agent’ in the western mountains (fig. 6), as Go- Scotland with Peulvast’s wholesale adaptation to ice in Nor- dard never quite spelled out (possibly because he scarcely way, albeit in a more arctic climate. penetrated to observe the surprising selectivity there). The Two contrasting modes of glacial erosion have been invo- extent to which gross lowering of the highly-dissected west ked in the Highlands. Sugden (1968) recognised ‘selective is attributable to areal glaciation, intensive selective linear

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erosion under the thickest ice, and pre-Quaternary fluvial incursions from a rejuvenated west coast, me- rits investigation – with Godard’s rhetorical question about the survi- val of ‘véritables knicks’ in mind. Theme 4: Watershed reconstruction and glacial breaching

Godard’s approach is at its most dated when he embarks on a meticu- lous, if poorly evidenced, analysis of the réseau hydrographique (p. 105). He observes that the pre- sent main watershed of NW Scot- land ne coïncide pas avec la ligne Fig. 8 Ð The anomalous large ‘fan-delta’ at the mouth of the 7 km-long River Ness is attri- des plus hauts sommets mais qu’el- buted to the jökulhlaup. It creates the site for the city of Inverness, and narrows the le zigzague de part et d’autre (p. Moray/ Firth sufficiently to permit its bridging at Kessock. The deltaic form is defined by 107). His Planche II identifies 14 the Caledonian Canal (left), River Ness (centre) and a former cliffline (centre right), with wooded ‘islands’ of Quaternary deposits surviving within the paleo-flood channel. View looking NE (Pho- pockets between Cape Wrath and tograph by kind permission of The Highlands Council). Mull where drainage network shape suggests capture by the short west- Fig. 8 Ð Le fan-delta anormalement vaste au débouché de la Rivière Ness (7 km de long), attribué au jökulhlaup du Glen Roy. Ce fan-delta a déterminé le site de la ville d’Inverness et flowing rivers, all displacing the di- a rétréci suffisamment le Moray/Beauly Firth pour avoir permis la construction du pont de Kes- vide east by a few miles (fig. 7), but sock. La forme deltaïque est délimitée par le Caledonian Canal (à gauche), la rivière Ness (au he offers no criteria for their selec- centre) et la ligne d’une ancienne falaise (au centre droit), avec des Ç îlots » boisés constitués tion. Nevertheless, this is the first de dépôts quaternaires qui ont survécu dans le paléochenal d’inondation. Vue vers le NE (cliché comprehensive attempt at pre-Qua- reproduit avec l’aimable autorisation du Highlands Council). ternary Highland watershed recons- truction, although Dury (1953) had spotted local displacements. Yet once again Godard is conservative as to the scale of landscape change, constraining himself to extant relief by contrast with ‘hazardous’ interpretations such as Bremner’s, which attributed the wide ‘through valleys’ of the northern High- lands to an ancestral divide out in The Minch since lost to a parodied catastrophe engloutissant les parties supérieures des bassins (p. 108). Given his lack of any bet- ter explanation, and his later adoption of concepts from Cloos and Fourmarier which envisage the ‘foundering of the Minch’ and subsequent upwarping of the NW mainland coast (p. 563) (cf. Hall, 1991), it might even be worth revisiting Bremner here. Godard acknowledges the role of glacial Fig. 9 Ð The paraglacial rock slope failure (RSF). View across upper part breaching by regional ice transfluent from from the NE, with the 5Ð15 m source scarp and trench (right centre, continuing up to the east in effecting some captures, attribu- skyline above snowpatch) misinterpreted by Godard as a perched ‘’ at 800 m ting its first recognition to German workers asl. This is one of the largest RSFs in Scotland within a cirque, affecting 0.4 km2 (pho- (Louis, 1934; Sölch, 1936) prior to Linton tograph: D. Jarman). (1949), while overlooking Cadell (1886) Fig. 9 Ð L’écroulement paraglaciaire du versant rocheux de Ben Hee. Vue sur la around Loch Lomond, which was admitted- partie supérieure depuis le NE, montrant l’escarpement de la couronne d’écroulement ly located beyond his study area. Godard d’une hauteur de 5 à 15 m ainsi que la gouttière (au centre droit, continuant jusqu’à la ligne d’horizon au-dessus de la plaque de neige), interprété par erreur par Godard makes one unusually bold leap in mapping comme une Ç moraine » perchée à 800 m d’altitude. Il s’agit d’un des plus grands Loch Shiel as a great fault-exploiting breach éboulements d’Écosse ayant eu lieu à l’intérieur d’un cirque, qui affecte une superficie in the watershed capturing the Glenfinnan de 0,4 km2 (cliché de l’auteur).

196 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

(p. 552), a submerged breach in fact, without equally suggesting such a possible origin for the Pentland Firth, as marine charts hint. And at the other end of his study area, Godard inexplicably shows the Sound of Mull as the preglacial route to the sea for his putative Loch Linnhe river, rather than the seaward Great Glen Fault, whereas Sissons (1967) more sensibly has the Sound as a glacial breach (while likewise overlooking the Pentland Firth). At the outset, Godard shrewdly questions whether all these breaches are entirely glacial (p. 107), some of them may well capitalise on fluvial Fig. 10 Ð The Sgurr nan Airgid RSF, with its prominent slip bulge into Strath Croe. incisions from the west coast, dating View from the SE. At 1.5 km2 it is one of the six largest RSFs in the mainland Highlands. The back to Paleogene rejuvenation if failure splits the skyline ridge at 600Ð800 m asl, and descends almost to sea level. A slightly- not the Permo-Triassic opening of deflected natural stream course down the right-hand side undercuts the steep and uncohesive the Minch. But for Godard et al. toe, promoting extensive gully erosion misconstrued by Godard as anthropogenic (photograph: D. Jarman). (2001) to suggest that such ‘expan- ding seaward-facing drainage basins Fig. 10 Ð L’écroulement rocheux de Sgurr nan Airgid, Kintail avec le bombement proémi- were affected by glacial transfluen- nent de la masse déplacée vers Strath Croe. Vue du sud-est. Avec une étendue de 1,5 km2, il s’agit d’un des six plus grands éboulements rocheux des Hautes Terres d’Écosse continenta- ce after their main arteries had le. La masse effondrée interrompt la crête sur la ligne d’horizon à 600-800 m au-dessus du breached major divides’ (paraphra- niveau de la mer et descend presque au niveau de la mer. Le cours d’un ruisseau se trouve légè- sed and emphasised) may take this rement dévié sur le côté droit et sape le lobe escarpé et peu cohésif du matériel effondré. Ceci too far. Extreme divide zig-zags déclenche une érosion ravinante que Godard avait interprétée par erreur comme étant d’origine associated with breach-captures, anthropique (cliché de l’auteur). whether locally in the Highlands (Hall and Jarman, 2004) or regional- basin, which is preferable to Dury’s (1953) limited diversion ly in the Torngat Mts (tracked by the Quebec-Labrador (fig. 7); he proposes a half-hearted restitution at the head of boundary) must surely have regional ice transfluence as the , which is not adopted by Hall (1991), and an main driver. Godard’s synthesis rather avoids the role of gla- implausible reversal of Loch More in NW Sutherland. Ho- cial transfluence and breaching, and this seems to be a wever, he often underestimates the scale of breach capture, surprising lacuna in the French school generally, given its and overlooks several major possibilities. As a result, Go- interest in glaciated passive margins. dard’s reconstructed line zigzags even more frenetically bet- ween Loch Monar and Beinn Dearg, when Glen Carron, Theme 5: Ice limits Glen Torridon, and even upper could all reaso- nably be construed as major breaches of the same ilk as A remarkable feature of Godard’s view of geomorphology Loch Shiel (fig. 7). Indeed his discussion of Torridon as a is his almost total disdain for glacial deposits. This aligns him dome of radial drainage (p. 183), borrowing from Linton with most geologists in Scotland who until recently have (1957), unduly limits his thinking here, and is at odds with taken little interest in superficial cover, although for them it his dismissal of this model in the summation (p. 610). is a concealing irritant whereas for him it is simply a distrac- Godard’s cautious appraisal of the main mountain water- tion from the solid relief. He is not unaware of the efforts of shed gives way to sweeping reconstructions across Donner or Charlesworth in identifying Perth or Highland Sutherland and the half-drowned undulations of Orkney Readvances (p. 618), and he alludes to the earliest work of (fig. 7). He has an uncharacteristic blind spot with the geo- Sissons on meltwater channels and raised beaches, but he graphy of the Pentland Firth, which is nowhere discussed. feels no compulsion to enter the lists. Indeed it is rare to find His Planche II shows the divide crossing it from near John any mention of a glacial epoch, and then only in a dismissive o’ Groats to South Ronaldsay, up the east side of Scapa Flow context: la ‘Scottish Readvance’ qui n’est pourtant qu’un and looping across Mainland to the low islands of Eday and stade tardif du Würm (p. 604). Sanday. A more plausible westerly line might be invoked This disdain is refreshing, given the energy since devoted from Dunnet Head across to the hills of Hoy and thence to to mapping ice limits and retreat patterns and shorelines, the hillier islands of and Westray. Remarkably, notably those of the Loch Lomond Stadial (Younger Dryas) Godard is able to see the Westray-Stronsay firth, which is by Sissons and his school. Taking the Plio/Pleistocene glacial not structural like Scapa Flow, as a glacial lowering of a col era as a whole, the Loch Lomond Stadial is in fact rather insi-

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 197 David Jarman gnificant in its erosive effects, mainly redistributing deposits (fig. 8). British rivers invariably indent the coastline, yet this already in the system. Indeed, Godard goes on to dismiss the unique protrusion is on Britain’s shortest effective major évolution postglaciaire of the Highlands as tout cela ne river, only 10 km long from the foot of Loch Ness, the représente qu’un aménagement de détail (p. 357), an obser- depths of which must have trapped all the Holocene sedi- vation worth pondering when setting research priorities. ment from its large catchment (fig. 7). This double anomaly Godard becomes briefly animated by glacial limits at just passed unpondered by geomorphologists until boreholes for one point, when he identifies 15 nunataks in Sutherland, the the Bridge enabled Peacock and thence Sissons (1981) to Inner and Outer Hebrides, and Hoy, from the presence of adduce a catastrophic flood (jökulhlaup) from the Glen Roy blockfields which he argues (after Dahl in Norway) cannot proglacial lake overtopping the foot of Loch Ness and re- have developed postglacially (p. 604). From their peripheral mobilising Quaternary deposits in the valley. Godard must distribution he generates a fairly tentative and incomplete often have travelled through Inverness, and describes quite map of ice-cap contours (fig. 177); he observes that its rapid minor glacifluvial features on these shores; Agassiz (1841) decline northwards is consistent with the lesser glacio-iso- had verified the Glen Roy parallel roads. static recovery observed there. A more surprising blind spot is with rock slope failure This may be the first attempt to visualise a main ice-cap (RSF). Godard recognises the extensive RSF activity on the configuration for the Scottish mainland, Geikie (1873, cliffs of Skye, Eigg, Mull, and Morvern, but associates it 1878) having identified a trimline on the Outer Hebrides; it exclusively with Tertiary volcanic lithology (p. 629), while was evidently overlooked by Sissons (1967; 1976a) and finding little to say about the process or its significance Boulton et al. (1977), who envisaged total submersion by other than attributing it to ‘decompression’ after deglacia- ice. Ballantyne et al. (1998) impressively map a consistent tion. But he does not perceive the 200 or more RSFs which trimline pattern across the northern Highlands and Inner He- occur all over the mainland part of his area on Precambrian brides by cosmogenic nuclide dating. They acknowledge schists and most other lithologies, despite some being very Godard’s conceptual achievement, but dismiss his mapping large (reaching 3 km2 with 8 m-high antiscarps on Beinn as erroneous. In fact, Godard’s shape is essentially that of Fhada) and some being conspicuous (; slopes Ballantyne et al., but ~100 m higher. This is not a grave of ). RSF in all its manifestations had been reco- error, and Ballantyne et al. are a little uncharitable in faul- gnised in the Alps (Heim, 1932) if not yet published for ting a pioneering insight which occupies a mere two pages NW Scotland, although Johnstone of the British Geological and draws on observations from a small sample of summits Survey was recording them in the Western Highlands in the visited not with this prime aim in mind. Ballantyne et al. 1960s, and Bailey and Maufe (1916) had described them as also confine their interpretation to the ‘last ice sheet’ whe- endemic in the area. Had he been aware of it as reas Godard assigns his configuration simply to the maxi- an upland phenomenon, Godard would doubtless have been mum glaciaire, which embraces the whole epoch. Trimlines quick to appreciate the significance of RSF as a contributor have moved up and down over the various glacials, and Go- to gross erosion over repeated glacial-paraglacial cycles, as dard is simply looking at actual summits which appear never well as its direct influence on mountain shaping (Jarman, to have been affected by active ice. In fact, both are proba- 2002, 2006). bly observing the upper limit of obvious glacial erosion, ra- As it is, Godard makes a delightful error in misinterpre- ther than ice sheet upper limits (A. Hall, pers. comm., 2006). ting the headscarp and slip trench of the Ben Hee RSF as a A commendable ability to see the Pleistocene epoch as a bourrelet morainique laissé par un petit glacier perché, tar- whole pervades Godard’s work. Thus he takes Linton’s diglaciaire (Photo 17). Unfortunately he cites this as his best (1959) observation that cirque floor levels rise steadily from example for the extraordinary freshness of fragile forms of west to east, and analyses two transects to identify no less accumulation at high levels (p. 603); Haynes (1977) recti- than five generations of cirque development (his fig. 179). fied this detail without extending her critique to the rest of Perhaps wisely, he then restricts his interpretation to older his œuvre (fig. 9; Jarman and Lukas, 2007). More serious- and younger cirques, following an observation by Louis ly, he misattributes gully erosion in Strath Croe to human (1934) in the Loch Maree area (his Planche VII). This pre- activity (p. 335), failing to spot the bulging landslip toe of figures work on old cirques in Scotland (Sugden, 1970) and Sgurr nan Airgid (fig. 10); and he alludes to the gorge in Sweden (Holmlund, 1991), and on palimpsest landscapes Glen Shiel (p. 335, 613) without appreciating the associa- generally (Kleman, 1992). tion of breaching, deepening, and narrowing with the large (1.25 km2) and fairly prominent RSF of Sgurr na Ciste Some blind spots: the River Ness fan; Duibhe (Fenton, 1991; Jarman, 2003, 2007). rock slope failure Geomorphological combat It is instructive to learn from blind spots such as the Pent- land Firth in an otherwise outstanding eye for terrain. One Godard and the British geomorphological prominent example that long escaped notice is the large establishment ‘deltaic fan’ at the mouth of the River Ness, which has faci- litated the growth of Inverness as a regional capital, and the Godard delights in taking on the British geomorphologi- Kessock Bridge across the Moray-Beauly Firth narrows cal establishment and in spearing any weaknesses

198 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape mercilessly, an entertaining sport, but with risks. Thus he argues for complete chalk cover from thin deposits followed contrasts his own cautious mapping of sub-Devonian surfa- for long distances (Ireland-Hebrides): c’est allez un peu plus ce traces with l’ébauche globale du relief extrapolated à la vite en besogne semble-t-il, an over-hasty interpolation. Une manière de Bremner (p. 569). He taunts Bremner with three telle assertion demande à être confrontée avec les faits. grave objections, including monadnocks carved in the ORS, Swingeing criticism from an upstart for a doyen. And Go- which should not exist above an exhumed pre-Devonian dard cannot resist a final stab: le brillant mais fragile écha- surface, and, circonstance aggravante, have similar forms to faudage imaginé par Linton runs into too many structural those cut in the basement rocks (p. 567). He admits in intro- and stratigraphical difficulties, and the grand name of King ducing his problèmes d’ensemble to an unresolved one: how is deployed to underline this (p. 572). do we identify the respective roles of exhumed topographies If Linton was aware of these attacks, he does not seem to and Tertiary planations in the present relief? He ridicules have been sufficiently troubled to respond, and they have some attempts as assez fantaisistes et bien éloignées des passed unremarked subsequently by even such pugnacious réalités (p. 563); yet while minimising Bremner’s predevo- British workers as Sissons, as have Godard’s occasional nian surface in favour of his Tertiary planations, he is happy lapses in applying the same rigorous logic to his own to extend his niveau pliocène over large swathes of knock- constructs. It would also have been helpful had he made it and-lochan terrain where in effect it is exhuming his own clearer when ideas were his own or where he was benefiting pretorridonian landscape. from previous workers; in places (for example in his eluci- In similar quixotic vein, he tilts at Wilson’s ambitious dation of a sub-Torridonian surface) one gains the impres- notion of an ancient watershed extending from Lewis to sion that the NW Highlands were previously unexplored, the Faeroes, with its beheaded river valley remnants cros- while to encounter a pellucid appreciation of his three main sing Orkney (laissons à l’auteur la responsabilité de ses surfaces, and of the terrain anomaly manifesting as his Ulla- affirmations, p. 552, sic!) yet his own wayward alignment pool-Dornoch géoflexure transversale, in Peach et al. across the archipelago (above; fig. 7) might equally be (1912) brings a distinct frisson of ‘déjà vu’. described as ‘assez fantaisiste’. Indeed, Godard recons- tructs entire drainage networks extending well out onto the Rapp and Godard: contrasts in reputation continental shelf (his Planche II), linking up submarine ba- building sins which may be tectonic in origin, or carved by major ice streams (Stoker and Bradwell, 2005). The lack of field By way of comparison, another major thesis published in evidence or solid argument for his hydrographic recons- the same era, also after a decade of fieldwork, is still wide- tructions takes us back into a more primitive era of arm- ly cited as a landmark in studying erosional processes in a chair physical geography. northern mountain environment. Rapp (1960) pioneered But it is when he comes to David Linton that he dons the process quantification and might be judged far more mantle of giant-killer, most notably in the affair of la surfa- influential internationally than Godard’s thesis, yet it dealt ce infracénomanienne (p. 570). Godard is rightly sceptical almost exclusively with a single, atypical side valley in of the notion of a continuous chalk cover over the High- northern Sweden, and its results have never been replica- lands, which Linton (1951) and many others advocated to ted. Indeed one of its findings, which is an inferred rate of explain the superimposed easterly drainage pattern, and scarp retreat during Holocene times, has been nullified by which even Sissons (1967) reluctantly endorses. He admits reattribution of most of the valley-floor giant boulder he cannot refute it, but ‘paleogeography hardly pleads in its deposit to a single RSF source at the head (Jarman, 2002). favour’. His destruction of the Lintonian hypothesis de- The influence of Rapp’s methodologically-seminal thesis serves to be celebrated for its ruthless logic. It unfolds as has arguably been assisted (in Darwinian terms) by his follows: if the sub-Cretaceous base was irregular, then we crafting a very readable, easily assimilated magnum opus, must renounce the idea that today’s very smooth high level by his politesse in recognising all antecedents and avoi- elements are fragments of a great initial surface of uplift. So ding combative language, by being anchored within the this is probably why Linton does regard the Cairngorm and Swedish establishment, and by being published in English. Grampian plateau fragments as traces of a sub-cenomanian By contrast, Godard failed to ensure publication in an surface très regulière, bombée asymétriquement durant le accessibly condensed form in English, and to our eyes at Tertiaire. But if the basement surface is very regular, Linton least his themes disappeared into the impenetrable thickets does not need to invoke another very regular chalk surface of French geomorphology. Where ‘Godard (1965)’ is cited on top of it. This is ‘un luxe coûteux et inutile’ in Godard’s today, it is more out of bibliographic diligence than becau- own raised eyebrows, cheekily prefaced nous sommes tentés se of what he actually has to say, merely registering that he de dire, because elle ajoute à une première hypothèse une once worked in NW Scotland. Rapp became a highly-suc- seconde tout aussi invérifiable. We might also ask if the per- cessful, widely-known figure in the anglophone as well as iod between the upper Jurassic and the upper Cretaceous the continental geo-community (and a good friend of was long enough to inscribe on the basement as perfect an Godard), publishing primarily in English, whereas Godard erosion surface as Linton wishes: Godard suggests we need confined his managerial activities to France: the sole inter- the whole of the Cretaceous and the Eocene, with (semi- national congress featured in his CV is Paris 1984, while )arid climate periods, to achieve this. Moreover, Linton of his entire published œuvre of 86 items, only six are in

Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 199 David Jarman

English, of which only three are significant papers in trans- limpsest landscapes. (vii) The most detailed and systematic lation or important contributions to edited volumes attempt at reconstruction of a preglacial main watershed in (Godard, 2006). the Highlands to date, recognising its consistent eastward displacement by some combination of glacial breaching and Concluding evaluation: Godard’s preglacial fluvial incision. (viii) The most meticulous ela- achievements in mountain landscape boration of ancient landscapes revealed by exhumation evolution across each of the major unconformities, and the fullest re- cognition of the extent to which they influence the present relief. He was also one of the first to challenge the ortho- Summary of key insights and ideas doxy of Mesozoic submergence and planation, and the Ter- of present relevance tiary emergence of a uniform chalk surface on which the proto-drainage was held to be inscribed and become super- Godard (2006) describes himself today as a physical imposed. (ix) His championing of the widespread survival geographer (indeed he only mentions ‘geomorphology’ of summit elements of considerable antiquity, not just in flat post-1965 in respect of crystalline basements), and as a residuals, but in smooth yet sometimes quite steep hill- generalist, concluding his career review with a plea for forms, including inselbergs, monadnocks, and ramparts of convergence over divergence in research which should be varying relationship to geology and structure. Although he heard in Britain too. In fact Godard is an exceptional struc- does not develop an integrated interpretation of these pre- tural geomorphologist and climatic geologist, and a great glacial upland surface remnants, including their possible synthesiser. However silent he may have become on the evolutionary descent from post-orogenic relief, he is clear significance of his original researches, he acknowledges that they are far from a Davisian peneplain let alone a cra- his grounding in Scotland’s laboratory of contrastes mor- tonic ultiplain. (x) The fullest flowering in Scotland if not phostructuraux… marquées par une longue histoire Britain of the erosion surface school of landscape interpre- paléoclimatique (2006). tation; coherent, yet cautiously constrained by real observa- This reappraisal has focused on his researches into the tions. He identifies families of surface facets, which might evolution of the NW Highlands as a mountain landscape, plausibly relate to former base levels in a real landscape of neglecting his even more extensive work around the coasts complex history. He factors in geological controls in relief and in the archipelagoes. In the uplands, his insights, ideas, differentiation, although he pays less attention to slope de- and achievements of lasting value and contemporary rele- velopment. He paves the way for etch-planation theory, vance include: (i) A holistic approach to landscape evolu- which has yet to be applied in the western Highlands. tion – firmly grounded in geology, but not inhibited by over- literal rock-strength preconceptions; aware of climate, hy- A nexus of issues for landscape evolution drology, and process; but interested primarily in outcomes and the synthesis of contributory factors. (ii) His remar- The most contentious and intriguing issues emerging kable powers of geomorphological observation and inter- from this review are in the field of long-term landscape evo- pretation, both in fine detail and over a broad canvas. Many lution, which is finally returning to favour in Britain. They of his ‘worked examples’ remain almost unknown, and have only been touched upon in this review, and are drawn would benefit from exhumation when a new ‘Scenery of together here as an agenda for the integrated research Scotland’ to succeed Sissons (1967) is written. (iii) A clear espoused by Godard: (i) Etch-planation – how it is suppo- eye for the actual, often localised incidence of glacial ero- sed to work in complex, mid-latitude, passive margin, sion. Here he was and still is something of a lone voice. His orogen-root crystalline basement terrain such as Scotland; systematic ‘cutting down to size’ of the considerable but not (ii) multi-storeyed relief: the extent to which erosion surfa- wholesale effects of glaciation merits re-evaluation, in the ce fragments represent pulsed marine base-level changes, or light of more recent thinking on warm- and cold-based ice. relate to more local controls, or have evolved separately or (iv) A disdain for the relatively trivial landshaping role of coevally; (iii) geologically-controlled versus bevelled glacial deposits and glacifluvial/paraglacial/Holocene pro- relief, and implications for the siliciclastic weathering pro- cesses. Their study, both spatially and quantitatively, has blem; (iv) early Tertiary uplift: how and indeed whether a dominated Scottish geomorphology since the 1960s, to the major Paleocene upwarping, with or without tilting, occur- neglect of the Godardian approach. (v) The first recognition red in the Highlands; (v) Mesozoic submergence: the extent of nunataks in the NW Highlands as potential indicators of and influence of sediment cover and its subsequent remo- the maximum extent and shape of former icecaps. (vi) His val, reassessing AFTA and offshore deposit indications; (vi) astute discernment of glacial features of different ages the present summit surface (paleic relief) as a direct des- (cirques, valleys, breaches) building a picture of glaciation cendant from the Caledonian unconformity; (vii) long-term as a progressive and fluctuating process, rather than the drainage evolution and divide migration, including influen- conventional image of a single if interrupted event, in which ce of tectonic events; (viii) present disposition, dissection, the last glaciation stands as a proxy for all that went before. and absolute elevation of high ground and relative contri- Here he anticipates by three decades work in Sweden on pa- bution of Cenozoic (fluvial) and Quaternary (glacial)

200 Géomorphologie : relief, processus, environnement, 2007, n¡ 2, p. 177-204 Godard on the Scottish landscape

erosion including breaching of divides; (ix) effects of long- Bremner A. (1942) – The origin of the Scottish river system – Part term isostatic buoyancy and incision in driving relief III. Scottish Geographical Magazine, 58, 99-103. accentuation. Cadell H.M. (1886) – The Dumbartonshire Highlands. Scottish It would be especially interesting to compare and Geographical Magazine, 2, 337-347. contrast Scotland with other Caledonide ranges, notably the Charlesworth J.K. (1957) – The Quaternary Era (2 volumes). Scandes, where recent work in geophysics, offshore data, Edward Arnold, London, 2300 p. and terrain analysis has yielded significant insights into their Clayton K.M., Shamoon N. (1999) – A new approach to the relief landscape evolution, with the possibility of a paradigm shift of Great Britain III. Derivation of the contribution of neotecto- if reappraisals of the tectonic driving factors prove valid nic movements and exceptional regional denudation to the (e.g., Nielsen et al., 2007). present relief. Geomorphology, 27, 173-189. To conclude: it is high time to revisit the Highlands of Doré A.G., Cartwright J.A., Stoker M.S., Turner J.P., White Scotland as a microcosm of multi-storeyed and glaciated N. (eds.) (2002) – Exhumation of the North Atlantic Margin: mid-latitude relief, harnessing the still-tangential concerns Timing, mechanisms, and implications for petroleum explora- of British and French geomorphology to interpret the tion. Geological Society of London, Special Publication 196, interactions of shifting climates and tectonics, and armed 498 p. with the pioneering observations, insights and approaches of Dury G.H. (1953) – A glacial breach in the north-western high- Alain Godard. lands. Scottish Geographical Magazine, 69, 106-117. Fenton C.H. (1991) – Neotectonics and palaeoseismicity in NW Acknowledgements Scotland. Unpublished PhD thesis, university of Glasgow, 403 p. I am immensely indebted to J. Gordon, for his continuing Geikie J. (1873, 1878) – On the glacial phenomena of the Long encouragement and for lending me a copy of Godard for Island or Outer Hebrides. Quarterly Journal of the Geological several years; to Y. Gunnell for hand-holding this conver- Society of London, 29, 532-545 and 34, 819-870. sion of the original hommage; and to A. Hall for valuable Gillen C. (2003) –- Geology and landscapes of Scotland. Terra, discussions, for an extremely thorough review, and for resis- Harpenden, 245 p. ting the temptation to rewrite it as magisterially as the Gjessing J. (1967) – Norway’s paleic surface. Norsk Geografisk subject deserves. I have not sought to interview Professor Tidsskrift, 21, 69-132. Godard, as the ‘epistemological’ purpose here is to revisit Godard A. (1957) – La surface prétorridonienne en Écosse. 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