Becke, Friedrich Johann Karl
Becke, Friedrich Johann Karl
(b. Prague, Czechoslovakia, 31 December 1855; d. Vienna, Austria, 18 June 1931)
mineralogy, petrography.
Becke’s father, Friedrich, originally a bookseller in Prague, became a railway employee at Pilsen in 1866 and later at Vienna. After attending several schools, Becke enrolled in 1874 at the University of Vienna, where he studied under the geologist Gustav Tschermak, who also published the journal Mineralogische und petrographische Mitteilungen. Becke soon devoted himself to mineralogy, and in 1878 he became Tschermak’s assistant. He had already gained notice in 1877 with his studies on Greek rock formations and his inaugural dissertation, Krystalline Schiefer des niederösterreichischen Waldviertels (1882), the first modern petrographical study of the metamorphic rocks of Austria. In 1882, at the age of twenty-seven, Becke was appointed associate professor (and later full professor) of mineralogy at the university of the Polish town of Czernowitz (now Chernovtsy, Ukrainian S.S.R.). While there, he discovered the differential solubility of dextrose crystals (1889).
In 1890 Becke was called to the University of Prague. Three years later he developed the method for the relative determination of the refraction of light by means of what since 1896 has been known as the Becke line. The procedure for measuring the angle of optical axes, which had been developed by François E. Mallard, was extended by Becke in 1895 for application to microscopic preparations. The following year he presented the Becke volume rule, which states that—assuming isothermal conditions—with increased pressure, the formation of minerals with the smallest molecular volume (the greatest density) will be favored.
In 1898 Becke went to the University of Vienna, where he attempted to classify the solidified rocks (plutonic rocks and lava). In 1903 he put forth the differentiation—based on their chemical composition and still used today—between the Atlantic group (of alkalic origin, mainly sodium and potassium) and the Pacific group (of calc-alkalic origin, characterized by high calcium and aluminum content). The mineral composition and the chemistry of both groups were correlated by Becke with E. Suess’s geotectonic concepts of an Atlantic Coast type (stratum) and a Pacific Coast type (mountain chain).
Becke’s work on crystalline schists was especially extensive. For the elucidation of the crystallization stratification he used Riecke’s rule, according to which mineral grains are relatively soluble in the direction of the applied pressure, whereas crystallization will proceed more rapidly perpendicular to the direction of applied pressure; thus the parallel planar texture of many rocks (“foliation”) develops independent of their original layering, and is characteristic for many metamorphic rocks. Becke’s explanation for the process in general considers only pressure as the cause, i.e., the process is static. According to more recent research, this is controversial.
For transformations in the solid state Becke introduced the terms crystalloblastic, granoblastic, porphyroblastic, blastophytic, blastogranitic, and blastoporphyric. With the aid of the graphic representation of rock components that he developed, it was possible, by utilizing the Si-U-L (Si = Si + Ti, U = Al + Fe + Mg, L = Ca + Na + K) traingle, to differentiate between orthorocks (solidified rocks transformed by metamorphosis) and pararocks (transformed sedimentary rocks). In 1909 Becke originated the term diaphtoresis for the adjustment of highly metamorphosed rocks to the conditions prevailing at lesser depths; the process is also known as regressive metamorphism. In later works he also dealt with the classification of the facies of metamorphic rocks, the mass movement during metamorphosis, and the graphic representation of rock analyses. His last publications dealt with the crystal systems and the nomenclature of the thirty-two symmetry point groups.
From 1899 on, Becke was the editor of Tschermark’s Mineralogische and petrographische Mitteilungen. Volume 38 of which was dedicated to him in honor of his seventieth birthday. He was director of the Mineralogical Institute of the University of Vienna from 1906 until 1927, and in 1911 he was appointed secretary-general of the Viennese Academy of Sciences. Immediately after World War I. Becke was rector of the University of Vienna, and in 1929 he received the Wollaston Medal of the Geological Society of London.
Becke did fundamental work in the elucidation of metamorphism, combining exact observations with bold and sophisticated theoretical considerations. Many students came to his institute to learn the methods of the “Vienna School.” His most important findings, especially those on metamorphic rocks, are still included in textbooks of mineralogy and geology.
BIBLIOGRAPHY
I. Original Works. Becke published many articles. Among the most important are “Beziehungen zwischen Dynamometamorphose und Moldkularcolumen.” in Neues Jahrbuch für Mineralogie. II (1896). 182–183; “Fortschritte auf dem Gebiete der Metamorphose,” in Fortschritte der Mineralogie, no. 2 (1911), 221–256, and no. 5 (1916). 210–264: Das Wachstum und der Bau der Kristalle, his inaugural lecture as rector of the University of Vienna (1918); “Struktur and Klüftung,” in Fortschritte der Mineralogie, no. 9 (1924). 185–220: and “Vorschläge zur Systematik und Nomenklatur der 32 Symmetrie-klassen.” ibid., nos. 11(1927), 289–292, and 12(1927, 97–103. He also published many works in Mineralogische und petrographische Mitteilugen between 1883 and 1928.
II. Secondary Literature. Of most value are A. Himmelbauer’s obituary of Becke in Mineralogische und petrographisch Mitteilugen. 42 (1932). i-viii: and the obituary in Vehandlungen der Geologischen Bundesanstalt Wien (1931). 239–241. A short but comprehensive article is by Walther Fischer, in Neue deutsche Biographie. 1 (1953). 708–709.
Hans BaumgÄrtel