Gignoux, Maurice

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GIGNOUX, MAURICE

(b Lyons, France, 19 October 1881; d Grenoble, France, 20 October 1955)

geology

Gignoux was born into a family of Swiss origin. A brilliant student, he was accepted by both the École Polytechnique and the École Normale Su peacuterieure. He chose the latter, which offered courses closer to his interests in research and teaching, and passed the agreacutegation in natural sciences with honors. Gignoux married Marie Garel in 1909; they had five sons and a daughter. In Lyons, under the su pervision of Charles Depeacuteret, he prepared a dis sertation on the Mediterranean Pliocence; presented in 1913, it remains the basis of more recent studies on the subject.

Gignoux’s career was interrupted by World War I, during which, because of his delicate health, he served in the meteorological research department of the army. After the war he was appointed professor of geology at the University of Strasbourg, now under French jurisdiction, where he taught stratig raphy, placing sediments in their structural frame for the first time. In 1925 he published Geacuteologie stratigraphique, a highly acclaimed work that ran to five editions and was translated into English, Russian, and Polish.

While at Strasbourg. Gignux collaborated with the Eumlcole Supeacuterieure du Peacutetrole and thus was able to pursue his interest in the tectonics of the evaporite ores. He extended his tectonic findings to the genesis of some Alpine structures, notably to the emplacement of the large nappes de charriage, and demonstrated, conversely, that the assumed remains of a gigantic nappe (the Suzette-Gigonadas massif in the southern Rhocircne Valley) were only rooted diapirs.

During his summer holidays Gignoux spent as much time as possible in the Alps, both for reasons of health and for the pleasure of being close to the mountains. In 1926 he accepted the chair of geology at the University of Grenoble in the Alps, succeeding Wilfrid Kilian, whose temporary assistant he had been in 1909. This was the beginning of the most productive period of his life, devoted to the innermost and most complex Alpine zones, particularly the Brianccedilon region. This tremendous undertaking lasted until World War II and produced the fundamental study Description geacuteologique du bassin supeacuterieur de la Durance, published in 1938 in collaboration with Leacuteon Moret. This study set the precedent for geological research in the Durance area for the next forty years.

The strength of Gignoux and Moret was that they outlined the existence of great structural zones, homogeneous in geological evolution and style of deformation and applied to these zones a special terminology (Brianccedilonnais zone, sub-Brianccedilonnais zone, Piedmont zone, etc.) that clarified the synthesis and became a model easily applied to other great mountain chains.

Among the series that Gignoux explored, one was an important turning point inhis research: the Embrunais flysch. Under the term flysch geologists class thick accumulations of sediments arranged in very regular beds, rhythmically repeated, that provide regularly stratified mountains. Furthermore, these flysch series are folded in a manner that suggested to Gignoux deformations arising from the sliding or “flowing” of the plastic mass of flysch down a slope, propelled by its own weight. This gravity tectonics theory had been put forward by the Swiss \ geologist Hans Schardt in 1893 but did not receive much attention until Gignoux proved its validity.

Although later studies did not fully consider Gignoux’s theory, it was recognized between 1948 and 1955 as far away as the United States. In 1955 Gignoux was awarded the Penrose Medal of the Geological Society of America, m rarely awarded out side the United States.

Like most true scientists, Gignoux never separated pure research from its applications. He was interested in the geological problems encountered in hydro electrical engineering, upon which he was frequently consulted. This work led to the publication of Geacuteo logie des barrages, written with Reynold Barbier, in 1955. This highly acclaimed work was not re published due to Gignoux’s premature death at Grenoble in 1955.

Throughout his life, Gignoux/7rsqo;s work was out standing in its simplicity and directness. Above all else, he retained the ability to arrive at an accurate interpretation of the observed facts. This persistent interest is well expressed by his choice of Pirandello’s words in the preface to his Géologie stratigraphique: “Un fatto eacute come un sacco, chevuoto non siregge. Percheacute si regga, bisogna prima farci entrar dentro la ragione” (“A fact is like a bag that will stand up only if filled with common sense”).

Throughout his life Gignoux worked ceaselessly, despite his chronic asthma, without regard for per sonal gain or honor. He received many prestigious appointments and honors; he was dean of the Faculty of Sciences at Grenoble, an officer of the Legion of Honor, a member of the French Academy of Sciences (1932), and a recipient of the Prix Gaudry of the Geological Society of France.

Gignoux was not only a famous geologist but also a fascinating man of extreme personal charm who was devoted to his family, friends, and students. He was also a knowledgeable musician. Through his professional and literary talents, his personal integrity, and his intellect, he made a great impression on those who knew him. Gignoux is remembered not only as the founder of the Alpine geological school that is still active, but also as a leader of European geology from 1938 to 1955.

BIBLIOGRAPHY

1. Original Works. Among Gignoux’s writings are Geacuteologie stratigraphique lpa)is, 1925; 5th ed., 1960), translated by Gwendolyn G. Woodford as Stratigraphic Geology (San Francisco, 1955); Description geacuteologique du bassin supeacuterieur de la Durance (Grenoble, 1938), written with Leacuteon Moret; Geacuteologie dauphinoise: Initiation aacute la geacuteologie par l’eacutetude des environs de Grenoble lpa)is, 1944; 2nd ed., 1952), written with Leacuteon Moret; Meacuteditations sur la tectonique d’eacutecoulement par graviteacute (Grenoble, 1948); “La notion de temps en geacuteologie et la tectonique d’eacutecoulement par graviteacute,” in International Geological Congress, Report of the 18th Session, Great Britain, pt. XIII (London, 1952); and Geacuteologie des barrages et des ameacutenagements hydrauliques lpa)is, 1955), written with Reynold Barbier.

II. Secondary Literature. A biography of Gignoux is Leacuteon More, “Maurice Gignoux (1881–1955),” in Bulletin de la Socieacuteteacute Geacuteologique de France, 6th ser., 6 (1956), 289–317.

Jacques Debelmas