GC: n
S: NatGeo – http://news.nationalgeographic.com/news/2014/03/140324-mudslides-natural-disasters-geology-science/ (last access: 30 October 2015). CDPH – http://www.bepreparedcalifornia.ca.gov/BEINFORMED/NATURALDISASTERS/Pages/LandslidesandMudslides.aspx (last access: 30 October 2015).
N: 1. Simple combination of mud (mid-14c., cognate with and probably from Middle Low German mudde, Middle Dutch modde “thick mud,” from Proto-Germanic *mud- from PIE *(s)meu-/*mu- (Buck), found in many words denoting “wet” or “dirty”) + slide (1560s, from slide (v.). As a smooth inclined surface down which something can be slid, from 1680s; the playground slide is from 1890. Meaning “collapse of a hillside, landslide” is from 1660s.).
2. First known use of mudslide: 1874.
3. A type of landslide, which occurs when the slope is saturated with water. This more destructive flow can pick up rocks, trees, houses and cars. As the debris moves into river and stream beds, bridges can become blocked or even collapse, making a temporary dam that can flood neighbouring areas. (GLIDE).
4. A mudslide (sometimes called a mudflow) is the most rapid (up to 80 km/h) and fluid type of downhill mass movement comprising of at least 50 per cent silt and clay-sized materials and up to 30 per cent water.
5. A mudslide may occur as a distinct phenomenon while a landslide is in progress.
6. A DEBRIS FLOW (commonly called a MUDSLIDE by the media) is a moving mass of loose mud, sand, soil, rock, water and air that travels down a slope under the influence of gravity. To be considered a debris flow, the moving material must be loose and capable of “flow”, and more than half of the solids in the mass must be larger than sand grains, including gravel, pebble, cobble and boulder sized material. The speed of a debris flow can reach of 100 miles per hour, although most commonly they are slow and move only a few feet per year downslope.
A MUD SLIDE (mud flow) is a mass of water and fine-grained earth materials that flows down a stream, ravine, canyon, arroyo or gulch. A MUDFLOW is a mass of water and sand-sized or smaller particles that can flow very rapidly. To be considered a mudflow, more than half of the particles must be sand sized or smaller. Mudlflows are the sandy, more watery counterparts of debris flows.
The media often use the term MUD SLIDE for events that are actually DEBRIS FLOWS or MUD FLOWS.
S: 1. http://www.allwords.com/word-mudslide.html (last access: 30 October 2015); OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=mud&searchmode=none; http://www.etymonline.com/index.php?allowed_in_frame=0&search=slide&searchmode=none (last access: 30 October 2015). 2. MW – http://www.merriam-webster.com/dictionary/mudslide (last access: 30 October 2015). 3. http://reliefweb.int/sites/reliefweb.int/files/resources/4F99A3C28EC37D0EC12574A4002E89B4-reliefweb_aug2008.pdf (last access: 30 October 2015). 4 & 5. TERMIUM PLUS (last access: 30 October 2015). 6. http://coloradogeologicalsurvey.org/geologic-hazards/debris-flows-fans-mudslides/definition/ (last access: 1 November 2015).
SYN: 1. mudflow (context). 2. mud flow, mud-flow (context).
S: 1. MW – http://www.merriam-webster.com/dictionary/mudslide (last access: 30 October 2015); TERMIUM PLUS (last access: 30 October 2015); EncBrit – http://global.britannica.com/science/mudflow (last access: 30 October 2015). 2. TERMIUM PLUS (last access: 30 October 2015).
CR: avalanche, erosion, eruption, landslide, natural disaster.
