191:. They are composed of at least 50% silt and clay-sized materials and up to 30% water. Because mudflows mobilize a significant amount of sediment, mudflows have higher flow heights than a clear water flood for the same water discharge. Also, sediment within the mudflow increases granular friction within the flow structure of the flow relative to clear water floods, which raises the flow depth for the same water discharge. Difficulty predicting the amount and type of sediment that will be included in a mudflow makes it much more challenging to forecast and engineer structures to protect against mudflow hazards compared to clear water flood hazards.
40:
271:
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When a mudflow occurs it is given four named areas, the 'main scarp', in bigger mudflows the 'upper and lower shelves' and the 'toe'. The main scarp will be the original area of incidence, the toe is the last affected area(s). The upper and lower shelves are located wherever there is a large dip (due
910:
Talling, P. J.; Wynn, R. B.; Masson, D. G.; Frenz, M.; Cronin, B. T.; Schiebel, R.; Akhmetzhanov, A. M.; Dallmeier-Tiessen, S.; Benetti, S.; Weaver, P. P. E.; Georgiopoulou, A.; Zühlsdorff, C.; Amy, L. A. (November 2007). "Onset of submarine debris flow deposition far from original giant landslide".
179:
After a mudflow forms, coarser sediment may be picked up by the flow. Coarser sediment picked up by the flow often forms the front of a mudflow surge and is pushed by finer sediment and water that pools up behind the coarse-grained moving mudflow-front. Mudflows may contain multiple surges of
335:. Normally a chilly 5 °C (41 °F), the lahar instantly raised the temperature to near 38 °C (100 °F). Today the bottom of Spirit Lake is 100 ft (30 m) above the original surface, and it has two and a half times more surface area than it did before the eruption.
247:
Mudflows can be caused by unusually heavy rains or a sudden thaw. They consist mainly of mud and water plus fragments of rock and other debris, so they often behave like floods. They can move houses off their foundations or bury a place within minutes because of incredibly strong currents.
235:
is a more general term than mudflow. It refers to the gravity-driven failure and subsequent movement downslope of any types of surface movement of soil, rock, or other debris. The term incorporates earth slides, rock falls, flows, and mudslides, amongst
851:
Kean, Jason W.; Staley, Dennis M.; Cannon, Susan H. (5 November 2011). "In situ measurements of post-fire debris flows in southern
California: Comparisons of the timing and magnitude of 24 debris-flow events with rainfall and soil moisture conditions".
217:
significantly altered more than 60 kilometers (37 mi) of the coastline. It was triggered by heavy rainfall and caused estimated damages of US$ 1.79 to US$ 3.5 billion, killed between 10,000 and 30,000 people, forced 85,000 people to
821:
Kean, Jason W.; McCoy, Scott W.; Tucker, Gregory E.; Staley, Dennis M.; Coe, Jeffrey A. (December 2013). "Runoff-generated debris flows: Observations and modeling of surge initiation, magnitude, and frequency: RUNOFF-GENERATED DEBRIS FLOWS".
71:
that has become liquified by the addition of water. Such flows can move at speeds ranging from 3 meters/minute to 5 meters/second. Mudflows contain a significant proportion of clay, which makes them more fluid than
342:
that disintegrated 60,000 years ago and produced the longest flow of sand and mud yet documented on Earth. The massive submarine flow travelled 1,500 km (930 mi) – the distance from London to Rome.
83:, a term applied indiscriminately by the mass media to a variety of mass wasting events. Mudflows often start as slides, becoming flows as water is entrained along the flow path; such events are often called
76:, allowing them to travel farther and across lower slope angles. Both types of flow are generally mixtures of particles with a wide range of sizes, which typically become sorted by size upon deposition.
180:
material as the flow scours channels and destabilizes adjacent hillslopes (potentially nucleating new mudflows). Mudflows have mobilized boulders 1–10 m across in mountain settings.
735:
105:
A statutory definition of "flood-related mudslide" appears in the United States' National Flood
Insurance Act of 1968, as amended, codified at 42 USC Sections 4001 and following.
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1029:
168:
size, the water content, and the slope of the topography. Fine grained material like mud or sand can be mobilized by shallower flows than a coarse
1042:
561:
202:, California, where they have destroyed many homes built on hillsides without sufficient support after fires destroy vegetation holding the land.
963:
Hungr, Oldirch; Evans, S. G.; Bovis, M. J.; Hutchinson, J. N. (August 2001), "A review of the classification of landslides of the flow type",
763:
587:
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off South Africa) occurred approximately 2.6 million years ago. The volume of the slide was 20,000 km (4,800 cu mi).
713:
Fletcher, Lara; Hungr, Oldrich; Evans, S G (1 February 2002). "Contrasting failure behaviour of two large landslides in clay and silt".
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310:
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331:, US The volume of material displaced was 2.8 km (0.67 cu mi). Directly in the path of the huge mudflow was
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676:
Dingle, R. V. (December 1977). "The anatomy of a large submarine slump on a sheared continental margin (SE Africa)".
176:
flow. Higher water content (higher precipitation/overland flow) also increases the potential to initiate a mudflow.
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Stock, J. D.; Dietrich, W. E. (1 September 2006). "Erosion of steepland valleys by debris flows".
624:"Enormous Submarine Landslide 60,000 Years Ago Produced The Longest Flow Of Sand And Mud On Earth"
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Iverson, RM; Reid, ME; LaHusen, RG (May 1997). "Debris-flow mobilization from landslides".
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in 1985. The mudflow destroyed more than 100 homes and claimed an estimated 300 lives.
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to mountain or natural drop) in the mudflow's path. A mudflow can have many shelves.
99:
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and/or mobilize loose sediment that is located in steep mountain channels. The 2006
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Areas where wildfires or human modification of the land have destroyed vegetation
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The areas most generally recognized as being at risk of a dangerous mudflow are:
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flowing through cracked bedrock may trigger a movement of soil or sediments in
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The world's largest historic subareal (on land) landslide occurred during the
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may also occur when strong rains on hill or mountain slopes cause extensive
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Slopes that have been altered for the construction of buildings and roads
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17:
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835:
295: in this section. Unsourced material may be challenged and removed.
184:
154:
126:
779:
Hungr, Oldrich; Leroueil, Serge; Picarelli, Luciano (4 January 2013),
902:
173:
734:
Hungr, Oldrich; Leroueil, Serge; Picarelli, Luciano (1 April 2014),
726:
606:"What was the largest landslide in the United States? In the world?"
187:
and therefore slow; others begin very quickly and continue like an
113:
1185:
1139:
222:, and led to the complete collapse of the state's infrastructure.
165:
146:
118:
112:
91:
38:
1322:
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The largest known of all prehistoric landslides was an enormous
195:
134:
68:
1011:
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The point where a muddy material begins to flow depends on its
264:
327:, a volcano in the Cascade Mountain Range in the State of
736:"The Varnes classification of landslide types, an update"
588:"Catastrophic Landslides of the 20th Century - Worldwide"
372:
Steep slopes and areas at the bottom of slopes or canyons
781:
The Varnes classification of landslide types, an update
785:
648:
488:
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43:
Mailboxes caught in a mudflow following the May 1980
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404:, occurred on Mt. Rainier's White River drainage.
548:
244:. They do not have to be as fluid as a mudflow.
30:"Mudslide" redirects here. For other uses, see
824:Journal of Geophysical Research: Earth Surface
1023:
999:United States Department of Homeland Security
794:Annual Review of Earth and Planetary Sciences
562:"What is a Landslide? – Geoscience Australia"
536:
8:
102:(outbursts from under glaciers or icecaps).
369:Areas where landslides have occurred before
1254:
1181:
1055:
1030:
1016:
1008:
965:Environmental & Engineering Geoscience
439:, Table 2, citing Cruden and Varnes, 1996
311:Learn how and when to remove this message
98:deposits on the flanks of volcanoes) and
67:involving fast-moving flow of debris and
564:. Ga.gov.au. 15 May 2014. Archived from
161:may have been caused by rogue drilling.
117:The Mameyes mudflow disaster, in barrio
775:. On-line publication 30 November 2013.
413:
883:Geological Society of America Bulletin
660:
7:
786:Hungr, Leroueil & Picarelli 2014
489:Hungr, Leroueil & Picarelli 2014
477:Hungr, Leroueil & Picarelli 2014
473:Hungr, Leroueil & Picarelli 2013
461:Hungr, Leroueil & Picarelli 2013
449:Hungr, Leroueil & Picarelli 2014
437:Hungr, Leroueil & Picarelli 2014
425:Hungr, Leroueil & Picarelli 2013
421:Hungr, Leroueil & Picarelli 2014
293:adding citations to reliable sources
125:, was caused by heavy rainfall from
25:
678:Journal of the Geological Society
378:Channels along streams and rivers
325:1980 eruption of Mount St. Helens
1003:Facts about Mudflows/Landslides.
513:Fletcher, Hungr & Evans 2002
501:Iverson, Reid & LaHusen 1997
269:
194:Mudflows are common even in the
90:Other types of mudflows include
854:Journal of Geophysical Research
280:needs additional citations for
183:Some broad mudflows are rather
549:Kean, Staley & Cannon 2011
1:
814:10.1146/annurev.earth.25.1.85
715:Canadian Geotechnical Journal
1392:Potentially hazardous object
348:largest submarine landslide
145:that continue as mudflows.
1469:
985:10.2113/gseegeosci.7.3.221
79:Mudflows are often called
29:
752:10.1007/s10346-013-0436-y
537:Stock & Dietrich 2006
398:, also known as Leda clay
32:Mudslide (disambiguation)
698:10.1144/gsjgs.134.3.0293
261:Largest recorded mudflow
94:(involving fine-grained
226:Mudflows and landslides
205:On 14 December 1999 in
610:U.S. Geological Survey
592:U.S. Geological Survey
130:
109:Triggering of mudflows
48:
213:, a mudflow known as
127:Tropical Storm Isabel
116:
42:
874:10.1029/2011JF002005
788:, with page numbers.
475:, §6.1 Mud failure;
289:improve this article
137:, or high levels of
27:Form of mass wasting
977:2001EEGeo...7..221H
933:10.1038/nature06313
925:2007Natur.450..541T
895:2006GSAB..118.1125S
889:(9–10): 1125–1148.
866:2011JGRF..116.4019K
806:1997AREPS..25...85I
690:1977JGSoc.134..293D
649:Talling et al. 2007
568:on 22 December 2015
451:, pp. 170, 185
340:submarine landslide
1043:list by death toll
836:10.1002/jgrf.20148
215:The Vargas tragedy
131:
49:
47:volcanic eruption.
1453:Natural disasters
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1407:Geomagnetic storm
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1117:Soil liquefaction
1039:Natural disasters
919:(7169): 541–544.
321:
320:
313:
252:Mudflow geography
159:Sidoarjo mud flow
16:(Redirected from
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1339:Tropical cyclone
1333:Tornado outbreak
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1182:
1135:Pyroclastic flow
1127:Volcano eruption
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903:10.1130/B25902.1
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830:(4): 2190–2207.
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762:, archived from
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238:other categories
133:Heavy rainfall,
55:, also known as
45:Mount St. Helens
21:
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1448:Landslide types
1443:Weather hazards
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1307:Cyclonic storms
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1238:Limnic eruption
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957:Further reading
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766:on 27 July 2014
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402:Osceola Mudflow
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346:By volume, the
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800:(1): 85–138.
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358:Areas at risk
357:
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352:Agulhas slide
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315:
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278:This section
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240:of hillslope
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41:
37:
33:
19:
1397:Impact event
1385:Astronomical
1319:Thunderstorm
1314:Bomb cyclone
1178:Hydrological
1147:Volcanic ash
1112:Seismic risk
1077:
1060:Mass wasting
968:
964:
916:
912:
886:
882:
857:
853:
827:
823:
797:
793:
780:
768:, retrieved
764:the original
743:
739:
721:(1): 46–62.
718:
714:
681:
677:
656:
644:
632:. Retrieved
628:ScienceDaily
627:
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591:
582:
570:. Retrieved
566:the original
556:
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532:
520:
508:
496:
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468:
456:
444:
432:
427:, p. 28
416:
381:Areas where
361:
345:
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322:
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298:
287:Please help
282:verification
279:
255:
246:
230:
229:
204:
193:
182:
178:
163:
151:debris flows
132:
104:
89:
85:mud failures
84:
80:
78:
74:debris flows
65:mass wasting
60:
56:
52:
50:
36:
1412:Solar flare
1298:Megadrought
1258:Temperature
1231:Megatsunami
1210:Storm surge
1205:Flash flood
1083:Debris flow
784:. Draft of
661:Dingle 1977
634:21 February
572:16 December
463:, p. 4
385:is directed
333:Spirit Lake
200:Los Angeles
139:groundwater
123:Puerto Rico
100:jökulhlaups
96:pyroclastic
1437:Categories
1093:Earthquake
1051:Geological
740:Landslides
670:References
396:Quick clay
329:Washington
301:April 2015
143:landslides
1422:Hypernova
1417:Supernova
1365:Firestorm
1280:Heat wave
1275:Ice storm
1270:Cold wave
1073:Avalanche
1068:Landslide
844:130762677
706:129229469
409:Citations
232:Landslide
211:Venezuela
189:avalanche
121:, Ponce,
18:Mudslides
1372:ARkStorm
1360:Wildfire
1265:Blizzard
1165:Sinkhole
941:18033295
760:38328696
390:See also
220:evacuate
170:sediment
135:snowmelt
81:mudslips
61:mud flow
57:mudslide
1355:Derecho
1329:Tornado
1290:Drought
1226:Tsunami
1078:Mudflow
973:Bibcode
949:4373921
921:Bibcode
891:Bibcode
862:Bibcode
802:Bibcode
770:16 July
686:Bibcode
198:around
185:viscous
155:erosion
53:mudflow
947:
939:
913:Nature
842:
758:
704:
630:. 2007
207:Vargas
174:debris
147:Floods
92:lahars
1348:Other
1219:Other
1186:Flood
1140:Lahar
945:S2CID
840:S2CID
756:S2CID
702:S2CID
350:(the
196:hills
172:or a
166:grain
119:Tibes
1323:Hail
1191:List
1098:List
937:PMID
772:2014
636:2021
574:2015
149:and
69:dirt
981:doi
929:doi
917:450
899:doi
887:118
870:doi
858:116
832:doi
828:118
810:doi
748:doi
723:doi
694:doi
682:134
291:by
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