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In the mid-1850s, Thomas Henry Huxley, who coined the term 'coccolith', described their presence in oceanic sediments dredged from the sea floor. Subsequent recognition of their occurrence in the Upper Cretaceous English Chalk, largely unconsolidated pelagic sediment, and similar, more lithified limestones in the Jurassic of the Alps, led to their being considered major rock-forming elements through much of geological time, although they are now known to be limited to the Late Triassic–Recent interval. Unlike Charles Darwin, who did not travel abroad following the voyage of the Beagle, Huxley made a number of trips to Italy and Switzerland and is recorded as a guest in the exclusive Hotel Kursaal Maloja in the Engadin in 1893. While staying there, he made a number of excursions on foot and his presence was thought significant enough that it is recorded in an inscribed granitic stone tablet, erected in 1896, describing him as'the illustrious writer and naturalist'. His rambles would have led him past outcrops of tectonically emplaced true oceanic calcareous sediment of Early Cretaceous age, here shown to have originally contained coccoliths that were largely destroyed under the imprint of Alpine metamorphism of sub-greenschist to greenschist facies. To this extent, Huxley could have come close to recognizing true oceanic sediments exposed on land, but the dissimilarity between these Swiss Alpine deposits and the friable English Chalk would not obviously have led to the investigation of the former for the organisms he had christened as 'coccoliths'. [ABSTRACT FROM AUTHOR]

In 1890, former students of Arnold Guyot at the University of Neuchàtel dedicated a 'large glacial boulder from Neuchâtel' to his memory, now in front of Guyot Hall at Princeton University. We established that this block originated with all certainty from Upper Carboniferous conglomerates of the Salvan–Dorénaz Basin, the relics of which crop out in the Alps of western Switzerland and eastern France. During the Last Glacial Maximum, the boulder travelled from the lower Rhône Valley on the back of the Pleistocene Rhône Glacier to Neuchâtel from where, later, it crossed the Atlantic and was transported to Princeton. Guyot's name is familiar to geologists because of the term 'guyot', introduced 1946 by Harry Hess for 'curious flat-topped peaks scattered over millions of square miles in the Pacific basin', many of which are now known to represent drowned carbonate platforms. [ABSTRACT FROM AUTHOR]

Rudolf Trümpy (1921-2009) was one of the great Alpine geologists of the twentieth century and an influential figure in the international geological community. He played a dominant role in the change of opinion concerning the Alpine evolution by showing that normal faulting dominated the early development of the Alpine realm from the Triassic to the early Cretaceous. This provided a convenient model for later plate-tectonic interpretations of collisional mountain belts. His further recognition of strike-slip faulting during all stages of the Alpine evolution presaged the realisation that the Alps were not built by a simple open-and-shut mechanism. Trümpy was educated during an intellectual lull, a time when simplistic models of the earth behaviour inherited from the middle of the nineteenth century became prevalent under the influence of a close-minded, positivist approach to geological problems. This period, which we term the Dark Intermezzo, lasted from about 1925 to 1965. The grand syntheses of Suess and Argand which preceded this period were viewed from this narrow angle and consequently misunderstood. It was thought that earth history was punctuated by global orogenic events of short duration taking place within and among continents and oceans whose relative positions had remained fixed since the origin of the planet. These views, summarised under the term 'fixism', were developed when the ocean floors were almost totally unknown. When data began coming in from the post World War II oceanographic surveys, the world geological community was slow to receive and digest them. Trümpy followed these developments closely, realising that his work was important in placing the geology of the mountain belts within the emerging, new theoretical framework. He adopted the position of a critic and emphasised where detailed knowledge of the Alps, unquestionably the best known mountain belt in the world, supported and where it contradicted the new ideas. His voice was listened to carefully and subsequent developments have shown his critique to have been prescient. It is regrettable that he did not publish some of the theoretical criticisms he communicated to his colleagues during scientific meetings and informal conversations. His hesitance in becoming involved in theoretical arguments in geology may have stemmed partly from his scientific upbringing during the Dark Intermezzo and partly because he genuinely believed that he was better off sticking to what he thought he knew for sure. He nevertheless stressed that it is important for geologists 'to dream'. It is often said about teachers that one should do what they say, not what they do. In Trümpy's case, it was the opposite. Both scientifically and as a human being, he was a most admirable man. [ABSTRACT FROM AUTHOR]

Abstract: A new reconstruction of Alpine Tethys combines plate-kinematic modelling with a wealth of geological data and seismic tomography to shed light on its evolution, from sea-floor spreading through subduction to collision in the Alps. Unlike previous models, which relate the fate of Alpine Tethys solely to relative motions of Africa, Iberia and Europe during opening of the Atlantic, our reconstruction additionally invokes independent microplates whose motions are constrained primarily by the geological record. The motions of these microplates (Adria, Iberia, Alcapia, Alkapecia, and Tiszia) relative to both Africa and Europe during Late Cretaceous to Cenozoic time involved the subduction of remnant Tethyan basins during the following three stages that are characterized by contrasting plate motions and driving forces: (1) 131–84Ma intra-oceanic subduction of the Ligurian part of Alpine Tethys attached to Iberia coincided with Eo-alpine orogenesis in the Alcapia microplate, north of Africa. These events were triggered primarily by foundering of the older (170–131Ma) Neotethyan subduction slab along the NE margin of the composite African–Adriatic plate; subduction was linked by a sinistral transform system to E–W opening of the Valais part of Alpine Tethys; (2) 84–35Ma subduction of primarily the Piemont and Valais parts of Alpine Tethys which were then attached to the European plate beneath the overriding African and later Adriatic plates. NW translation of Adria with respect to Africa was accommodated primarily by slow widening of the Ionian Sea; (3) 35Ma–Recent rollback subduction of the Ligurian part of Alpine Tethys coincided with Western Alpine orogenesis and involved the formation of the Gibraltar and Calabrian arcs. Rapid subduction and arc formation were driven primarily by the pull of the gravitationally unstable, retreating Adriatic and African slabs during slow convergence of Africa and Europe. The upper European–Iberian plate stretched to accommodate this slab retreat in a very mobile fashion, while the continental core of the Adriatic microplate acted as a rigid indenter within the Alpine collisional zone. The subducted lithosphere in this reconstruction can be correlated with slab material imaged by seismic tomography beneath the Alps and Apennines, as well as beneath parts of the Pannonian Basin, the Adriatic Sea, the Ligurian Sea, and the Western Mediterranean. The predicted amount of subducted lithosphere exceeds the estimated volume of slab material residing at depth by some 10–30%, indicating that parts of slabs may be superposed within the mantle transition zone and/or that some of this subducted lithosphere became seismically transparent. [Copyright &y& Elsevier]