Bertrand, Marcel-Alexandre

(b. Paris, France, 2 July 1847; d. Paris, 13 February 1907)

geotectonics, stratigraphy” general geology.

Bertrand’s father was the mathematician Joseph Bertrand. Marcel studied at the École Polytechnique and the École des Mines in Paris. After graduation he worked in the Geological Survey of France, and in 1886 he succeeded his teacher Béguyer de Chancourtois at the École des Mines. In 1896 the Académie des Sciences elected him to the chair Pasteur had held.

Inspired by the writings of Eduard Suess, Bertrand always maintained a concern for what he called the grand problems of general geology. Early in his career he devoted his attention to the general problems of mountain structure while producing a dozen sheets of the geologic map of France. He solved the anomaly of le Beausset (and was awarded the Prix Fontannes by the Geological Society of France for it in 1889) by discovering that the islands of Triassic sediments resting on Cretaceous formations are the eroded remains of an enormous overturned fold. His conception of very large-scale overturned folds and over-thrusts related the geological structure of Provence to that of the Alps. Bertrand was the first to conceive of the overthrust structure of the Alps, and by this theory of grandes nappes he attempted to connect the structures of the Pyrenees, Provence, and the Alps. His analysis of horizontal crustal compression and the displacements resulting from it won the Prix Vaillant of the Académie des Sciences of the Institut de France in 1890, but the essay was not published until 1908.

Bertrand developed an orogenic wave concept that he used to separate earth history into natural divisions on the basis of successive periods of intense folding and orogeny, each division identified with a chain of mountains. Working from Suess’s brilliant synthesis, Bertrand demonstrated in 1887 that the Caledonian, Hercynian, and Alpine deformation produced consecutively those three mountain chains, thus building up the European continent gradually from north to south.

In 1894, at Zurich, Bertrand offered his very original conception of the complete sedimentary cycle with its recurring facies; each cycle represented one of the fundamental deformations. He showed that four kinds of facies are repeated in the different mountain chains, typically gneiss, followed by schistous flysch, then coarse flysch and coarse sandstone. At this time he also added the Huronian orogeny of Precambrian time to the other three deformations. In essaying a mechanism for these orogenies, Bertrand revived, then abandoned, the tetrahedral plan of the earth of Lowthian Green and Michel- Lévy.

BIBLIOGRAPHY

I. Original Works. Oeuvres géologiques de Marcel Bertrand, Emmanuel de Margerie, ed., 3 vols. (Paris, 1927–1931), contains all Bertrand’s published works except the sheets of the Carte géologique détaillée de la France (scale 1:80,000); “Études sur les terrains secondaires et tertiaires dans les provinces de Grenade et de Malaga,” in Mémoirés de l’Académie des sciences, 30 (1899), 377–579; and the posthumously: published “Mémoire sur les refoulements qui ont plissé l’écorce terrestre et sur le rôle des déplacements horizontaux,” ibid., 50 (1908), 1–267. It includes Bertrand’s own notice of his scientific works to 1894.

II. Secondary Literature. The most complete biographical notice is the éloge by Pierre Termier, in Bulletin de la Société geologique de France, 4th ser., 8 (1908), 163–204, including a bibliography. Other notices are Archibald Geikie, in The Quarterly Journal of the Geological Society of London, 61 (1908), 1-liv; W. Kilian and J. Révil, in Annales de l’Université de Grenoble, 20 (1908), 15–35; And Otto Wilckens, in Centralblatt für Mineralogie, Geologie, und Paläontologie (1909), 499–501, V. V. Beloussov, in his Basic Problems in Geotectonics (New York, 1962), pp. 39–43, sets some of Bertrand’s contributions in historical perspective.

Bert Hansen