Four loess pioneers: Charles Lyell, F. von Richthofen, V.A. Obruchev, L.S. Berg

The four loess pioneers were Charles Lyell, Ferdinand von Richthofen, Vladimir Obruchev and Lev Berg. Their life spans covered the period 1797-1956. They each contributed significant thoughts and ideas to the development of the study of loess deposits. Their loessic ideas can be related to their life experiences and to their own particular approaches to their chosen branches of science. Their ideas can also be set in a framework of scientific development at a time when scientific knowledge was increasing rapidly and new fields and areas of study were being demarcated. The directions that they indicated and the ideas that they implanted still influence loess research today, and some problems that they touched on remain unresolved. The basic Lyell idea of lacustrine or fluvial deposition followed by uplift held sway from about 1830 till around 1880. Richthofen developed his ideas on aeolian deposition from 1870 and Obruchev developed his ideas after the Potanin expedition, in 1895. Berg offered his concept of loess formation by weathering and soil formation in 1916, and was a keen proponent until his death in 1950. Many scholars offered ideas and proposals on the problem of loess deposit formation but the four chosen individuals appear to predominate, and have delivered the paradigms that have shaped loess research since the 1830s. Richthofen has probably acquired a little too much credit for the aeolian theory, and Obruchev not enough. Obruchev delivered a fully worked out aeolian approach which encompassed post-depositional changes to the loess material. Berg, with his total concentration on post depositional changes was only considering half a picture. Some of his ideas were important but his one eyed view meant that many scholars neglected them.