Oskar Lenz, a German-Austrian geologist, geographer and explorer, studied geology and mineralogy at the University of Leipzig from 1866 and in 1870 was awarded the doctoral degree. That same year he went to Vienna, Austria, as a teacher, but in 1872 joined the Geologische Reichsanstalt. He did geological mapping in the southern and eastern regions of Austria and Hungary and published several papers on the geology of Germany and Austria from 1870 onwards. From 1874 to 1877 he explored Gabon, particularly along the Ogowe River, for the Deutschen Gesellschaft zur Erforschung Aequatorial-Afrikas. His second expedition, during 1879-1880, took him from Morocco through the Sahara desert to Timbuktu (now Tombouctou) and Senegal.
In 1885 Lenz was appointed as professor of geography at the University of Chernivtsi, Ukraine. That same year he set out on another expedition, this time to map the Congo River. During 1885 to 1887 he travelled across the African continent from the mouth of the Congo River to the mouth of the Zambezi in Mozambique. Many publications were based on his travels, including a number of papers on the geology and geography of the regions he visited. For example, "Petrefacten von der Loango-Kueste" dealt with fossils from near the mouth of the Congo River and was published in the Verhandlungen der Kaiserlich-Koeniglichen Geologischen Reichsanstalt (Vienna) in 1877, followed by "Geologische Mitteilungen aus W[est] A[frika]" the next year. A book, Skizzen aus West Afrika, also appeared in 1878, and a geological map of West Africa in 1882. Other books and papers described his travels in North Africa (1879-1883), and East Asia, his expedition to the Congo (1885-1887), and the geology of Greenland.
One paper relating to more southerly parts of Africa, "Ueber eine der Prororoca aehnliche Fluterscheinung am quaquafluss in Suedostafrika" [locality not identified] appeared in Petermanns Mittheilungen in 1889. In 1896 he published a paper in Prague on "Ophir und die ruinen von Zimbabye in Suedostafrika", dealing with the Zimbabwe ruins. He dealt with the same subject in a subsequent paper, "Ueber alt-arabische Ruinenstaetten in Maschonaland und deren Beziehungen zum biblischen Ophir", in the Mittheilungen des Kaiserlich-Koeniglichen Gesellschaft (Vienna, 1897, pp. 187-211). The titles of these two papers reflect opinions typical of the time before the ruins were first investigated by archaeologists early in the twentieth century. Lenz also described "British Zambesia, ein neues englisches Reich in Suedafrika" in Fernschau.
In 1887 Lenz was appointed as professor at the University of Prague (now Praha, Czech Republic), a post he held to his retirement in 1909. Oskar Lenz should not be confused with Otto Lenz, a foundation member of the South African Association for the Advancement of Science and partner in the engineering firm Reunert* and Lenz.