The Bubnoff unit (abbreviated B) is a unit of speed defined as 1 micron per year. In other words, 1 B is equal to 1 meter in 1,000,000 years or 1 millimeter in 1 millennium.[1] It was defined in 1969.[2]
The Bubnoff unit is employed in geology to measure rates of lowering of earth surfaces due to erosion[3] and is named after the Russian (German-Baltic) geologist Serge von Bubnoff (1888–1957).[4] An erosion speed of 1 B also means that 1 m3 of earth is being removed from an area of 1 km2 in 1 year.[5] Compared to everyday phenomena, erosion is under most circumstances (excluding rapid events like landslides) an extremely slow process, calling for such a specialized unit. For instance, the current average rate of erosion over the Earth's landmasses has been estimated at 30 B (30 m in a million years). There are, however, great regional differences in erosion speed. As an extreme example, the watershed area of the Semani River in Albania is eroding at a rate of almost 3000 B (3 millimeters per year), the river having been estimated to transport about 4600 tons of earth per year from the average square kilometer in its watershed.[6]
The Bubnoff unit was introduced because of a desire for a standard unit to replace the multitude of units in use, such as feet per year, centimeters per year, meters per decade, and so on. One criticism leveled was that by introducing the Bubnoff unit, it would obscure the rate of erosion behind a unit no one besides specialists understood.[7]
References
edit- ^ Allaby, Michael (2007). Encyclopedia of weather and climate. New York, NY: Facts on File. p. 501. ISBN 9780816063505. OCLC 69792154.
- ^ Fischer, Alfred G. (1969). "Geological Time-Distance Rates: The Bubnoff Unit". Geological Society of America Bulletin. 80 (3): 549. doi:10.1130/0016-7606(1969)80[549:GTRTBU]2.0.CO;2. ISSN 0016-7606.
- ^ Allaby, Michael (2013). A Dictionary of Geology and Earth Sciences (4. ed.). Oxford University Press. p. 82. ISBN 9780199653065. OCLC 835969159.
- ^ Allaby, Michael; Park, Chris (2013). A Dictionary of Environment and Conservation (2. ed.). Oxford University Press. p. 60. ISBN 9780199641666. OCLC 810946330.
- ^ Kearey, P. (2001) The New Penguin Dictionary of Geology. Penguin, London, 336 pp.
- ^ Hall, A. (1993) The Work of Rivers. In Duff, D. (ed.) Holmes' Principles of Physical Geology, Chapman & Hall, London, 312-345.
- ^ Berg, Robert R.; Gangi, Anthony F. (1971). "Bubnoff Unit: An Objection" (PDF). Geological Society of America Bulletin. 82 (12): 3475-3476. doi:10.1130/0016-7606(1971)82[3475:BUAO]2.0.CO;2.
- ^ "Convert 1 m/s (meter per second) to Bubnoff units". Convert 1 m/s (meter per second) to Bubnoff units. Wolfram Alpha. Retrieved 1 June 2021.
 | This geomorphology article is a stub. You can help Wikipedia by expanding it. |