“Time-specific facies”—a great concept introduced by a great man: Otto H. Walliser

The concept of “Time-Specific Facies” (TSF) was proposed in the 1980s by an outstanding palaeontologist/geologist: Otto Heinrich Walliser. His idea of comparing similar developments, which span a certain period of time within the geologic record, offers great potential for age assignment, long-range correlation, studies of palaeoenvironments, and other applications. By not tying his novel idea to a restrictive definition, he enabled present and future scientists to use the term in a relatively broad sense. As with the entire volume, this article pays tribute to this great scientist.