Vernadsky, Valdímir Ivanovich

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VERNADSKY, VALDíMIR IVANOVICH

(b. St. Petersburg, Russia, 12 March 1863; d. Moscow, U.S.S.R., 6 January 1945)

mineralogy, geochemistry,biogeochmistry.

Vernadsky’s father, Ivan Vasilievich Vernadsky, a member of the gentry, was a professor at Kiev and Moscow universities and later at the Main Pedagogical Institute and the Aleksandrov Lycèe in St. Petersburg. From 1857 to 1864 he edited liberal economic journals, in which he spoke against serfdom. His mother, Anna Petrovna Konstantiovich, came from a Ukrainian landowning family and taught singing.

While still at the classical gymnasium, Vernadsky became interested in chemistry but was also attracted by history, philisophy, and Slavic languages. From 1881 to 1885 he was a student in the Natural Sciences Section of the Physics and Mathematics Faculty at St. Petersburg University. According to Vernadsky, while he was there Mendeleev’s brilliant lectures awakened a strong desire for knowledge and its application. Dokuchaev, who lectured on mineralogy and crystallography, supervised Vernadsky’s first scientific research. After graduation Vernadsky remained at the university to prepare for a teaching career, and from 1886 he was curator of the mineralogical collection at the university. In the latter year he married Natalia Egorovna Staritskaya; they had two children. From 1888 to 1890 Vernadsky traveled abroad. Interested in the structure of crystal substances, he worked in Groth’s crystallographic laboratory at Munich and in Le Châtelier’s and Fouqué’s laboratories at the Collège de France. He also made geological excursions in Italy, Germany, Switzerland, Austria, France, and England. Vernadsky subsequently traveled widely in Europe and North America in order to become acquainted with areas of geological and mineralogical interest, to participate in international scientific congresses, and to study the organization of scientific research and higher education.

In the fall of 1890 Vernadsky became a Privatdozent in mineralogy and crystallography at Moscow University, In 1891 he defended his master’s thesis, “O gruppe sillimanita i roli glinozema v silikatakh” (“On the Sillimanite Group and the Role of Alumina in Silicates”) and, in 1897, his doctoral dissertation, “O yavleniakh skolzhenia kristalli–cheskogo veshchestva” (“On the Phenomena of Gliding in Crystal Substances”). Vernadsky was appointed professor at Moscow University in 1898. The St. Petersburg Academy of Sciences elected him associate member in 1909 and academician in 1912.

Vernadsky was among those professors and teachers who, in response to the reactionary treatment of the university by the Ministry of National Education, left Moscow in 1911 and moved to St. Petersburg. In 1914 he became director of the Geological and Mineralogical Museum of the Academy of Sciences and a year later joined the Commisssion to Study the Natural Productive Forces of Russia, serving as its president in 1915–1917 and in 1926–1930. From June 1917 to the beginning of 1921 Vernadsky lived in the Ukraine. He was responsible for the creation of the Ukrainian S.S.R. Academy of Sciences in 1919 and was its first president. Following his return to Leningrad from Paris and Prague in 1926, he continued his scientific and organizational activity at the Academy of Sciences. In 1926 he founded and headed the Commission on the History of Knowledge of the Academy of Sciences of the U.S.S.R. and, the following year, the Section on Living Substances (now the V. I. Vernadsky Institute of Geochemistry and Analytical Chemistry). At Vernadsky’s suggestion, at the Seventeenth International Geological Congress, held at Moscow in 1937, an international commission was created to determine the absolute age of geological rock by radioactive methods; he was elected vice–president of this commission.

In the fist twenty-five years of his scientific career, Vernadsky was concerned with crystallography and, primarily, mineralogy, which he also studied later, when he turned to geochemistry, radiogeology, and biogeochemistry. Two important works devoted to the structure of crystalline substances were Vernadsky’s doctoral dissertation (1897) and Osnovy Kristallografii (“Fundamentals of Crystallography”; 1904), in which he developed the relation of crystal form to physicochemical structure and emphasized the importance of energetics in studying crystals.

Vernadsky opened a new, evolutionary direction in mineralogy. His research was presented in Opyt opisatelnoy mineralogii (“Experiment in Descriptive Mineralogy”; 1908–1922) and Istoria mineralov zemnoy kory (“History of Minerals of the Earth’s Crust; 1923–1936). Defining mineralogy as the chemistry and history of the minerals in the earth’s crust, he believed that “mineralogy, like chemistry, must study not only the products of chemical reactions but also the very processes of reaction” (Izbrannye sochinenia, II, 9)–and in the concept of mineral he included gases and water. In his works on mineralogy Vernadsky started from the premise that the purposes of mineralogy as a science are to establish the chemical composition of minerals; to establish the chemical composition of minerals; to explain the conditions necessary for chemical reactions involved in the genesis and paragenesis of minerals, and to study the conditions under which minerals change in the various zones of the earth.

Vernadsky’s works stated the laws of paragenesis of minerals, the concept of which had been introduced into mineralogy in 1849 by J. F. A. Breithaupt. In Paragenezis khimicheskikh elementtov v zemnoy kore (“Paragenesis of Chemical Elements in the Earth’s Crust” 1910), Vernadsky, starting from the capacity of isomorphic compounds to produce isomorphic mixtures–solid solutions–introduced the concept of natural isomorphic series of chemical elements. His table of elements in the earth’s crust consisted of eighteen series, each of them related to definite thermodynamic zones. Vernadsky distinguished three such zones: the weathering crust, the area of low temperature and low pressure; the area of metamorphism, the area of high pressure and moderate temperature; and the deep layers of the lithosphere-the area of magmatization– the area of high temperature and high pressure. He emphasized that “isomorphic series are transformed and change under the influence or changes of temperature and pressure” (lzbrannye sochinenia, I, 404). Vernadsky’s position was the basis for the development of the theory of paragenesis of elements and minerals, which was of great importance in the search for useful mineral deposits.

Vernadsky’s great contribution to mineralogy was his research on silicates and aluminosilicate minerals, which constitute a major part of the earth’s crust. The aluminosilicates had previously been considered to be salts of silicic acid and their acid properties to be attributable only to alumina. Vernadsky refuted this view in his master’s dissertation and showed experimentally a different structure of aluminosilicates, according to which aluminum in the most important rock–forming minerals– feldspares and micasa– is chemically analogous to silicon. He proposed the theory of the kaolin nucleus, composed of two atoms of aluminum, two of silicon, and seven of oxygen, and constituting the basis of many minerals. This theory has played an important role in explaining the structure, genesis, and classification of minerals. It was later confirmed by X-ray structural analysis, and it is now considered an established fact that silicon and aluminum in aluminosilicates are joined by atoms of oxygen placed at the points of tetrahedropns, which represent the framework of the aluminosili cates, the cavities of which are filled with large cautions.

Vernadsky’s basic works in geochemistry are of great importance. Geochemistry is a science of the twentieth century. although the term was introduced into the literature in 1838 by C. F. Schonbein. Defining geochemistry a science, Varnasky wrote;

Geochemistry scientifically studies . . . the atoms of the earth’s crust and, as much as possible, of all the planets. It studied their history, distribution, and motion in space–time, their genetic relationships on our planet. It is sharply distinguished from mineralogy, which studies the history of the earth in the same space and the same time only as the same space and time only as the history of compounds of atomas– molecules and crystals [Izbrannye sochinemia,I, 14]

Vernadsky’s geochemical research, which he conducted intensively from 1908 to 1910, was generalized in Ocherki geokhimii (“Sketches in Geochmistry” 1927, 1934). which first appeared in French as La géochimie (Paris, 1924). Directly connected with this work is Biofera (“Biosphere”, 1926). Examining the early period of geochemistry, Vernadsky showed the importance of the contrbuttions of many scientists in different countries, including Robert Boyle, In his geochemical works he gave remarkable works he gave remarkable descriptions of many elements of the earth’s crust. He prepared precise data on the chemical composition of the earth’s crust to a depth of twenty kilometers and tabulated the chemical elements of this layer in wight percentages.

The history of the chemical elements in the earth’s crust, Vernadsky showed, can be reduced to their migrations: the motion of atoms in the formation of compounds; their transformation into mobile liquids, gases, and solid bodies; and their assimilation into the respiration, nourishment, and metabolism of organisms.

These migrations in the crust of the earth create large systems of chemical equilibria or modes of occurrence of chemical elements. Vernadsky distinguished four such modes; molecules and compound in minerals, rocks, liquids, and gases; elements in living organisms; elements in magmas, occurring under conditions of high pressure and temperature; and dispersed elements. He paid much attention to the geosphere (the earth’s layers), between which the migration of chemical elements also occurs. Material on geospheres occupies a large portion of Ocherki geokhimii (“Sketches in Geochemistry”).

Vernadsky considered inaccurate the widely accepted view that the earth’s crust is the remnant of the first crust of a once–liquid mitten mass. In studying it, he found it convenient to distinguish, in a simplified form. the following layers; the biosphere, the layer occupied by all living things; the stratosphere, the layer of sedimentary rock; the metamorphic layer; the granite layer; and the basalt layer. The layers have a close genetic relations to each other, and cyclical transfers of chemical elements occur among them. Vernadsky believed that these processes have formed “burial layers,” including the granite, that have gone through the biosphere stage and thus should be called ex–bioshperes.

Vernadsky classified the elements of Mendeleev’s periodic system into six groups according to their role in the geochemical history of the earth’s crust: noble gases, noble metals, cyclical elements, “scattered” elements, strongly radioactive elements, and rare earths. The cyclical elements, which constitute about 99.7 percent of the weight of the earth’s crust, play the main role in the processes originating there.

Each element in a given geosphere enters into the compounds appropriate to it under given thermodynamic conditions. These compounds are broken down in the transition to another geosphere, where other compounds are formed. In this process, “after more or less prolonged and complex changes the element returns to the first compound and begins a new cycle, which is completed for the element by a new return to its primary condition” (Izbrannye sochinenia, I, 40). These cycles are partly reversible, however, and some of the atoms constantly leave the cycle. Vernadsky examined the sources of energy under the influence of which tectonic motions and transfers of substances in the earth’s crust take place. On the basis of work by Joly and Strutt (Lord Rayleigh), as well as his own research, he considered the energy released by the radioactive decomposition of elements to be one of the main sources of these processes: “The heat effect of radioactive decomposition has been so substantial that it allows us to discard the hypothesis of the once molten planet and provides a basis for a new scientific consideration of atomic heating of the substance of the planet, sharply distinct in its various localities’ (Izbrannye sochinenia), I , 225).

Vernadsky was one of the first to recognize radioactivity as a powerful source of energy. When even physicists did not clearly recognize its practical significance, he pointed out the responsibility of scientists for the consequences of the use of their discovery. He wrote in 1922:

We are approaching a great revolution in the life of humanity, with which nothing . . . earlier . . . can be compared. The time is not far away when man will take atomic energy into his hands. . . .This can occur in the near future; it may happen after a century. But it is clear that it will inevitably happen. Does man know how to use this power, to direct it to good and not to self–destruction? Has he . . . the ability to use this force, which science will inevitably give him? Scientists must not close their eyes to the possible consequences of their . . .work of . . . progress. They must consider themselves responsible for the consequences of their discoveries. They must relate their work to the best organization of all humanity [Ocherki i rechi, II , foreword].

In 1910 Vernadsky and his colleagues began to seek radioactive and to study them in the laboratory. Greatly concerned with radioactivity, Vernadsky later laid the foundations of a new science, radioactivity.

In the last twenty years of his scientific career Vernadsky and his colleagues, especially A. P. Vinogradov, concentrated on the chemical composition of plants and animals. At the same time he clarified the role of living organisms in reactions and transformations of chemical elements in the biosphere. He introduced into geochemistry the concept of living matter as the totality of living organisms expressed in terms of weight, chemical composition, and energy. Such an approach to the study of living matter allowed Vernadsky to express in mathematical form certain regularities of the multiplication of organisms. He showed the primary importance of living organisms as accumulators, transformers, and carriers of solar of energy in geochemical cycles.

The analysis of biogeochemical processes led Vernadsky to conclude that the main gases of the earth’s atmosphere–oxygen, nitrogen, and carbon dioxide–are created by living things. He indicated the immediate role of living matter in the concentration of many chemical elements in the earth’s crust, especially carbon, silicon, calcium, nitrogen, iron, and manganese. Living matter, he asserted, influences the entire chemistry of the earth’s crust and determines the history of almost every element in it. He also considered the possibility that the quantity of living matter on the earth apparently has been constant throughout geological time. There is another possibility, however: that the mass of living matter grows over geological time. Vernadsky is thus considered the founder of the theory of the biosphere and of a new area of geochemistry: biogeochemistry.

Vernadsky gave great attention to the hydrosphere. His research in this field is presented in Istoria prirodnykh vod (“History of the Waters of Nature”; 1931), in which he treats the mineralogy of water and explains the relation between water and the solid crust of the earth. In the first volume of Opyt opisatelnoy mineralogii (“Experiment in Descriptive Mineralogy”: 1908–1914), and in later works Vernadsky showed the substantial effect of human activity on the history of the earth. As a result of this activity the face of the planet is increasingly changing as are the chemical properties of its surface.

BIBLIOGRAPHY

I. Original Works. Vernadsky’s writings include “O gruppe silliamanita i roli glinozema v silikatakh” (“On the Sillimanite Group and the Role of Alumina in Silicates”), in Byulleten Moskovskogo obshestva ispytatelei prirody, 5 (1891), 1–100, 165–169: Ocherki i rechi (“Sketches and Speeches”), 2 vols. (Petrograd 1922); Biosfera (“the Biosphere”; Leningrad, 1926; Mosocow, 1967); Bigeokhimicheskie oocherki, 1922–1932 gg. (“Biogeochemical Sketches …; Moscow–Leningrad, 1940); Izbrannye sochineia (“Selected Works”), 6 vols. (Moscow, 1954–1960): and Khimicheskoe storenie bisofery Zemli ie ee Okryzhenia (“The Chemical STructure of the Earth and Its Environs”; Mosocow, 1965). A work still in MS is “Nauchnaya muslkak planetnoe yavelnie” (“Scientific Though as a planetary”), MOPscow, Archives of the Academy of Sciences, fond 518.

II. Secondary Literature See A. E. Fersman, Zhiznenny put akademika Vladimirie Ivanovicha Vernadskogo (“The Career of Academician .. Verndandsky”; Moscow, 1946); B. L. Liochkov, Vladimar Ivanovich Vernadsky. 1863–1945 (Moscow, 1948), with bibliography on 83–102; Materialy k biobibliografli unchenykh SSSR (“Materials for a Biobibliograph of Sciencetists of the U.S.S.R.,”), Chem ser.,, no 6 (Moscow–Leningard, 1947), devoted to Verndsky, K.V. Vlasov, “Valadimir Ivanovich Vernadsky,” in Lydi russkoy nauki (“People of Russian Science”; Moscow, 1962), 135–157; and A. P. Vinogradov, Vladimir Ivanovich Vernadsky (Moscow–Leningrad, 1947).

I. A. Fedoseyev