Obruchev, Vladimir Afanasievich

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OBRUCHEV, VLADIMIR AFANASIEVICH

(b. Klepenino, Rzhev district, Tver [now Kalinin] guberniya, Russia, 10 October 1863; d. Moscow, U.S.S.R., 19 June 1956)

geology, geography.

Obruchev was the son of Afanasy Aleksandrovich Obruchev, a personnel officer in the Russian army, and Paulina Hertncr, the daughter of a German pastor. After attending elementary school in Brest, he graduated from the technical high school in Vilna (now Vilnyus), where he showed a special interest in geography and the natural sciences, especially chemistry. In 1881 he won admission to the St. Petersburg Mining Institute, from which he graduated in 1886. It was there that he first became strongly interested in geology.

Obruchev showed outstanding abilities during his first Transcaspian expedition (1886–1888). He was assigned the task of studying the Transcaspian depression, discovering the conditions of the mobility of quicksand in the regions where railroads were being constructed, seeking water-bearing levels in the sands, and making observations of the Tedzhen and Murgab rivers and the ancient Amu-Darya river bed. His study of the action of the wind as a geological agent inspired a lifelong interest in wind processes, particularly in the production of loess. Obruchev’s interest in dynamic geology also dates from this expedition.

Contrary to the then prevalent opinion that the Transcaspian sands were of exclusively oceanic origin, Obruchev discovered convincing evidence that they were of triple origin—marine, continental, and fluviatile. Explaining the conditions under which immobile or slightly mobile sands become mobile, he suggested practical measures that were subsequently implemented for combating migrating sands.

In 1888 Obruchev accepted Mushketov’s offer to go to eastern Siberia as staff geologist of the Irkutsk Administration of Mines, with supervision of a vast territory that comprised part of Irkutsk and Yenisey provinces, and the Yakutsk and Transbaikal regions. The geology of Siberia subsequently remained his main scientific topic. Obruchev’s area of responsibility included the study of the geological structure of the area and distribution of useful minerals, especially gold, which was mined in the Olekma-Vitim district and the area surrounding Lake Baikal.

In 1889 Obruchev completed an expedition across the Pribaikal Mountains, studied mica deposits on the Slyudyanka River, looked for lapsis lazuli and lazurite in the Khamar-Daban range and graphite on the Baikal island of Olkhon, investigated mineral springs in the Nilova Desert, and prospected for brown coal on the banks of the Oka River (a tributary of the Angara). In 1890 and 1891 he inspected in detail the goldfields in the Olekma-Vitim basins. Goldfields in these districts—in contrast to those in other areas of Siberia were generally covered with a coating of loose glacial deposits to a depth of 60–180 feet. These layers prevented the gold-bearing ones from rewashing and preserved their extraordinary richness.

Having confirmed Kropotkin’s views on the pre-glacial history of the gold-bearing layers, Obruchev explained their origin not by the erosion of thick quartz lodes, as had been asserted, but from the gold disseminated in thin quartz veins and in pyrite, dispersed through certain layers of bedrock. The destruction of this rock in situ, at the bottom of valleys under river beds, endowed these deposits with their unique structure and enriched their gold, which was chemically extracted from pyrite. This explanation of the origin of gold deposits, given by Obruchev in 1900, has retained its importance.

Summarizing his predecessors’ results in “Geologi-chesky ocherk Irkutskoy gubernii (“;A Geological Sketch of Irkutsky Province,” 1890), Obruchev expressed his own views on the current question of the origin of the depression of Lake Baikal.

When one stands on an elevation at the edge of the majestic depression of Baikal, it is impossible to agree with Chersky’s opinion that this depression is the result of the combination of prolonged erosion and slow crustal folding. It is too deep and wide, and its slopes are too steep and precipitous. Such a depression could have been created only by faulting, and comparatively recently; otherwise its steep slopes would have been smoothed by erosion and the lake would have been filled with its products [Moi puteshestvia po Sibiri (“;My Travels Through Siberia”; 1948), p. 35].

Obruchev’s views on the origin of the Baikal depression were supported by Suess. Obruchev published more than thirty works during his four years with the mining administration. During the winters he worked in the eastern Siberian section of the Russian Geographical Society as director of affairs and curator of its museum.

From 1892 to 1895 Obruchev traveled through Mongolia and China as a member of the central Asian expedition. His work gained him a worldwide reputation as an explorer and geologist; the Russian Geographical Society awarded him the Przhevalsky Prize and the Great Medal of Constantine, and the Paris Academy of Sciences honored him for his contributions. His research was based on Suess’s synthetic work on the geology of central Asia. From Kyakhta to Kuidja, Obruchev investigated the steppe, the Gobi Desert, and the quicksands of the Ordos Desert: traveled throughout the loess area of northern China; spent time in the Alashan range; investigated the Nan Shan and eastern Kunlun ranges; visited the shores of Lake Koko Nor; traveled through all the oases of Kansu Province; traced the course of the Edsin Gol River; crossed the mountainous southwestern region of the Gobi and central Mongolia; and thus extended Richihofen’s research deep into central Asia to the north, northwest, and west. From along the eastern Tien Shan Mountains he came out into Kuldja. His two-volume diary of the expedition (1900–1901) has remained the only source material on certain areas of central Asia.

Through his work with the expedition Obruchev disproved Richthofen’s ideas about the Tertiary Lake Khanka in central Asia, showing that the multicolored deposits of the Khanka suite are continental. In addition he noted that continental conditions had prevailed there since the Mesozoic Era. He introduced significant corrections and additions into Richthofen’s theory of the formation and distribution of loess in China and central Asia. Contrary to Richthofen’s views, Obruchev asserted that there is no loess in those depressions of central Asia that are part of the area of weathering and wind erosion. Obruchev considered that it was precisely from this area that the loess was carried by wind to the borders of central Asia, mainly into northern China, where it was deposited, preserving and smoothing the forms of the ancient topography.

Returning to Irkutsk in 1895 as head of a special mining party, Obruchev spent the next three years studying the geology of Selenga Dauria (western Transbaikalia) along the route of the main line of the Trans-Siberian railway, then under construction. The material gathered on this expedition formed the basis for the conclusions presented in his Orografichesky i geohgichesky ocherk Yugo-Zapadnogo Zahaykalya (“;Orographical and Geological Sketch of Southwestern Transbaikalia”), for which the Russian Academy of Sciences awarded him the Helmersen Prize.

Advancing new ideas about the tectonics of Siberia, Obruchev believed that the Transhaikal, composed of huge stretches of granites and crystalline slates, was part of the oldest dry land of Eurasia, “of the ancient shield of Asia.” Around this skeletal nucleus, he believed, further growth of the continent had occurred in more recent periods, from the Paleozoic to the Quaternary. The concept of the “ancient shield of Asia,” raised in the works of Ivan Chersky and Obruchev, was accepted by Suess. Obruchev continued to develop it throughout his life.

Obruchev also developed the idea of the origin of a series of large depressions of the Transhaikal, tilled with Mesozoic and Cenozoic deposits. In his opinion these depressions are grabens, which appeared as a result of faulting of the rigid blocks of the ancient shield of Asia, and they are similar to the depressions of Lake Baikal. Obruchev subsequently developed a concept of the prime role of faulting in the formation of the surface and geological structure of Siberia.

From 1898 to 1901 Obruchev worked in St. Petersburg on the material from his expeditions to central Asia and Transbaikalia. In 1899 he studied geology in Germany, Switzerland, and Austria, where he became acquainted with Suess; and in 1900 he participated in the Eighth International Geological Congress in Paris. In 1901 he again returned to Siberia, to study the goldficlds on the Bodaybo River.

In 1901, on Mushkelov’s recommendation, Obruchev was invited to the Tomsk Technological Institute to organize a department of mining and to teach general geology. An outstanding teacher (1902–1912), he also founded the Siberian school of geology.

Continuing his research expeditions, Obruchev traveled to the border regions of Dzungaria in the summers of 1905, 1906, and 1909, with the aim of clarifying the interplay of the Altay and Tien Shan mountain systems. In his opinion the distinguishing feature of the topography is that the mountain heights are remains of an ancient plateau, broken by faults. The flat peaks are horsts (tectoniealiy raised blocks), while the hollows dividing them—the grabens—are zones of tectonic sinking along faults, filled in by large amounts of lake alluvium. Obruchev discovered traces in the mountains of two glaciations and established the presence of vertical zonation of vegetation.

After retiring from Tomsk in 1912, Obruchev settled in Moscow, continued writing up the results of his previous research, and conducted geological fieldwork by contract with private firms. In 1914 he traveled through the Russian Altay, and the following year his Ahayskie etyudy (“;Altay Studies”) appeared; the second sketch, “O tektonike Russkogo Allaya” (“On the Tectonics of the Russian Altay”), is of special interest for his analysis of the views of previous investigators, notably Helmersen, P. A. Chikhachev, G. E. Shchurovsky, Karl Ritter, Cotta, Chersky, and Suess.

In Suess’s presentation the Altay are folded mountains convex to the south, formed by tangential stresses of the earth’s crust. Obruchev, however, after studying the adjoining Dzungaria, concluded that the recent topography was primarily the result of faulting:

It was not ancient folds that caused this topography; they have long since been worn down and reduced to almost a plain. It was, rather, faults that turned the entire area into a combination of horsts and grabens. Such land cannot be called plicate; it was such in Paleozoic times but has long since lost its characteristic peculiarities; what now dominate here are more or less extensive stepped plateaux, broad plains, frequently arranged inconsistently with a stretch of Paleozoic sedimentary rock, of which the planed-off ends come to the surface [Izbrannye trudy, V (Moscow, 1963), 34].

On his trips through the Altay, Obruchev was especially concerned with relating the topography to the geological structure. He established the existence of a severe discrepancy in orographical maps in relation to the actual position of mountain ranges. In describing the topography, Obruchev counted three mountain chains: “The Russian Altay in its topography has little similarity to the system of narrow and long mountain chains of folded origin. It is, rather, an ancient plateau, a highland, broken down by faulting into more or less broad and long parts, frequently consisting of two or more ledges of different heights and divided by deep and wide fault valleys” (ibid., p. 43).

Obruchev was close to the truth; according to the latest data the mountainous Altay is a complex block-fault structure, formed as a result of an arched uplift, faulting, and uneven vertical displacements of separate blocks of an ancient peneplained surface of folded Paleozoic formations. The uplift occurred at the end of the Tertiary and was especially forceful in the mid- and upper Tertiary periods. The raised parts of the peneplain form mountain systems; the lowered parts are the hollows between mountains. Obruchev’s original treatment of the geomorphology of the Allay and Siberia was subsequently developed as an independent branch of science-neotectonics.

At the request of the Higher Council of National Economy, in 1918 Obruchev went to the Donets Basin to prospect for fire-clays and marls. Cut off from central Russia by the civil war, he was obliged to accept the post of professor of geology at the University of the Crimea, in Simferopol. In 1920 he returned to Moscow and the following year was appointed to the chair of applied geology at the Moscow Mining Academy. For the next eight years he taught advanced courses on ore deposits and field geology; his lecture material formed the basis for the texts Polevaya geologia (“;Field Geology”) and Rudnye mestorozhdenia (“;Ore Deposits”). The former is the best-known Soviet handbook for beginning geologists and covers the entire work cycle of the geologist-prospector.

In 1928 Obruchev reported on Chinese bess to the All-Union Geological Congress in Tashkent, of which he was also president. Elected a member of the Soviet Academy of Sciences in 1929, lie subsequently headed its Geological Institute and Committee for the Study of Permafrost. Working with materials gathered in China and Dzungaria, he began the compilation of the five-volume Istoria geologicheskogo issledovania Sibiri (“;History of Geological Research in Siberia”).

Obruchev retained a lifelong interest in the geography of Siberia, especially in the former glaciation of the northern region, already suggested by Kropotkin after the expedition of 1866. The formation of the topography of Siberia also occupied an important place in Obruchev’s geographical works. Defending the necessity’ of the geomorphological regionalization of Siberia, Obruchev wrote in the first volume of Geologia Sibiri (“;The Geology of Siberia,” 1935) that earlier characterizations of its regions, given by Kropotkin, Chersky. and Suess, had become outdated and required “certain more or less essential changes and additions on the basis of new data.” His delineation and characterizations of ten geomorphological regions have retained their importance.

Referring to the research of Hans Stifle and W. H. Bucher, Obruchev wrote in “Molodost relefa Sibiri” (“;The Youth Stage of the Topography of Siberia”), “At present, on the basis of the numerous investigations of the past decade, it is possible to assert with full justification that the topography not only of the ancient shield hut of almost all Siberia is young and was formed by movements during the Tertiary and post-Tertiary periods that attained in places quite a substantial amplitude.”

Obruchev also investigated the conditions of the origin and development of permafrost, its geographical distribution, and its influence on agriculture. For many years he was head of the Institute of Permafrost Management of the Soviet Academy of Sciences.

In 1937 Obruchev was head of the Soviet delegation to the Seventeenth International Geo1ogic1 Congress in Moscow, and in 1939 he became editor of the geological series of Izvestiya Akademii nauk SSSR. During World War II he was secretary of the Geological Sciences Section of the Soviet Academy of Sciences. A recipient of many Soviet medals and awards, he was corresponding member of the Royal Geographical Society and a member of the Russian Geographical Society, the American Geological and Geographical Societies, the Geological Society of China, the Hungarian Geographical Society, and the Deutsche Geophysikalische Gesellschaft.

A volcano in Transbaikalia, a glacier in the Mongolian Altay, a peak in the Russian Altay, and a steppe between the Murgab and Amu-Darya rivers are named for him. In 1941 a prize in his name was established for work on the geology of Siberia.

BIBLIOGRAPHY

I. Original Works. Obruchev’s published work comprises more than 2,000 pages of scientific works and more than 3,000 reviews for foreign journals, as well as teaching materials, classical works on geology and mining, and several science fiction novels. Only the basic works reflecting his scientific activity are given here.

His selected works were published as Izbrannye trudy, 6 vols. (Moscow, 1958–1964). His account of his journey completed at the request of the Imperial Russian Geographical Society was published as Tsentralnaya Azia, Severny Kitay i Nan-Shian (“;Central Asia, Northern China, and the Nan Shan”), 2 vols. (St. Petersburg, 1901). Subsequent fundamental works include Rudnye mestorozhdenia (“;Ore Deposits”), 2 vols. (Moscow-Leningrad, 1928–1929); Istoria geologicheskogo issledovania Sibiri (“;History of Geological Research on Siberia”), 5 pts. (Moscow-Leningrad, 193 I -1949); Polevaya geologia (“;Field Geology”), 2 vols. (Moscow-Leningrad, 1927; 4th ed., 1932); and Izbrannye raboty po geografii Azii (“;Selected Works on the Geography of Asia”), 3 vols. (Moscow, 1951). V staroy Sibiri “In Old Sibiria”; Irkutsk, 1958), contains articles, recollections, and letters from 1888 to 1955.

His science fiction works include Plutonia. Neobychaynoe puteshestvie v nedra Zemli (“;Plutonia. An Extraordinary Journey to the Depths of the Earth” Leningrad, 1924; repr., Moscow, 1958); V debryakh, Tsentralnoy Azii. Zapiski kladoiskatelya (“;In the Depths of Central Asia. Notes of a Treasure Hunter”), 3rd ed. (Moscow, 1955); and Zemlya Sannikova, ili poslednie onkilony (“;The Land of Sanniikov or the Last Onkilons”; Moscow, 1958).

II. Secondary Literature. On Obruchev and his work, see V. A. Obrechev (Moscow-Leningrad, 1946), materials for a bibliography published by the Soviet Academy of Sciences; and their notice in Bolshaya sovetskaya entsiklopedia (“;Great Soviet Encyclopedia”), 2nd ed., XXX, 390–392. See also A. N. Granina, “Deyatelnost V. A. Obrucheva v Vostochno-Sibirskom otdele Geograficheskogo obshchestva SSSR” (“;The career of V. A. Obruchev in the Eastern Siberian Section of the Geographical Society of the U.S.S.R.”), in Izvestiya Vsesoyuznogo geograficheskogo obshchetva, 89 , no. 2 (1957), 123–130; L. G. Kamanin and B. A. Fedorovich, “V. A. Obruchev—issledovatel Sredney i Tsentralnoy Azii i Sibiri” (“;V. A. Obruchev—Investigator of Middle and Central Asia and Siberia”), in Voprosy geomorfologii i paleogeografii Azii (“;Questions of Asian Geomorphology and Paleogeography” Moscow, 1955); E. M. Murzaev et al., Vladimir afanasevich Obruchev. Zhizn i deyatelnost (Moacow, 1959), on his life and work; and V. V. Obruchev and G. N. Finashina, Vladimir Afanasevich Obruchev (Moscow, 1965), with bibliography.

G. V. Naumov