180:. 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.
29:
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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
899:
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".
168:
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
324:. 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.
236:
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.
224:
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
840:
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".
206:
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
810:
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".
60:
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
331:
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.
72:, 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
65:, 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.
169:
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.
724:
94:
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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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
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550:
191:, California, where they have destroyed many homes built on hillsides without sufficient support after fires destroy vegetation holding the land.
952:
Hungr, Oldirch; Evans, S. G.; Bovis, M. J.; Hutchinson, J. N. (August 2001), "A review of the classification of landslides of the flow type",
752:
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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).
702:
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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320:, 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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Dingle, R. V. (December 1977). "The anatomy of a large submarine slump on a sheared continental margin (SE Africa)".
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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".
613:"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.
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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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284: in this section. Unsourced material may be challenged and removed.
173:
143:
115:
768:
Hungr, Oldrich; Leroueil, Serge; Picarelli, Luciano (4 January 2013),
891:
162:
723:
Hungr, Oldrich; Leroueil, Serge; Picarelli, Luciano (1 April 2014),
715:
595:"What was the largest landslide in the United States? In the world?"
176:
and therefore slow; others begin very quickly and continue like an
102:
1174:
1128:
211:, and led to the complete collapse of the state's infrastructure.
154:
135:
107:
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80:
27:
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The largest known of all prehistoric landslides was an enormous
184:
123:
57:
1000:
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The point where a muddy material begins to flow depends on its
253:
316:, a volcano in the Cascade Mountain Range in the State of
725:"The Varnes classification of landslide types, an update"
577:"Catastrophic Landslides of the 20th Century - Worldwide"
361:
Steep slopes and areas at the bottom of slopes or canyons
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The Varnes classification of landslide types, an update
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32:
Mailboxes caught in a mudflow following the May 1980
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393:, occurred on Mt. Rainier's White River drainage.
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233:. They do not have to be as fluid as a mudflow.
19:"Mudslide" redirects here. For other uses, see
813:Journal of Geophysical Research: Earth Surface
1012:
988:United States Department of Homeland Security
783:Annual Review of Earth and Planetary Sciences
551:"What is a Landslide? – Geoscience Australia"
525:
8:
91:(outbursts from under glaciers or icecaps).
358:Areas where landslides have occurred before
1243:
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1044:
1019:
1005:
997:
954:Environmental & Engineering Geoscience
428:, Table 2, citing Cruden and Varnes, 1996
300:Learn how and when to remove this message
87:deposits on the flanks of volcanoes) and
56:involving fast-moving flow of debris and
553:. Ga.gov.au. 15 May 2014. Archived from
150:may have been caused by rogue drilling.
106:The Mameyes mudflow disaster, in barrio
764:. On-line publication 30 November 2013.
402:
872:Geological Society of America Bulletin
649:
7:
775:Hungr, Leroueil & Picarelli 2014
478:Hungr, Leroueil & Picarelli 2014
466:Hungr, Leroueil & Picarelli 2014
462:Hungr, Leroueil & Picarelli 2013
450:Hungr, Leroueil & Picarelli 2013
438:Hungr, Leroueil & Picarelli 2014
426:Hungr, Leroueil & Picarelli 2014
414:Hungr, Leroueil & Picarelli 2013
410:Hungr, Leroueil & Picarelli 2014
282:adding citations to reliable sources
114:, was caused by heavy rainfall from
14:
667:Journal of the Geological Society
367:Channels along streams and rivers
314:1980 eruption of Mount St. Helens
992:Facts about Mudflows/Landslides.
502:Fletcher, Hungr & Evans 2002
490:Iverson, Reid & LaHusen 1997
258:
183:Mudflows are common even in the
79:Other types of mudflows include
843:Journal of Geophysical Research
269:needs additional citations for
172:Some broad mudflows are rather
538:Kean, Staley & Cannon 2011
1:
803:10.1146/annurev.earth.25.1.85
704:Canadian Geotechnical Journal
1381:Potentially hazardous object
337:largest submarine landslide
134:that continue as mudflows.
1458:
974:10.2113/gseegeosci.7.3.221
68:Mudflows are often called
18:
741:10.1007/s10346-013-0436-y
526:Stock & Dietrich 2006
387:, also known as Leda clay
21:Mudslide (disambiguation)
687:10.1144/gsjgs.134.3.0293
250:Largest recorded mudflow
83:(involving fine-grained
215:Mudflows and landslides
194:On 14 December 1999 in
599:U.S. Geological Survey
581:U.S. Geological Survey
119:
98:Triggering of mudflows
37:
202:, a mudflow known as
116:Tropical Storm Isabel
105:
31:
863:10.1029/2011JF002005
777:, with page numbers.
464:, §6.1 Mud failure;
278:improve this article
126:, or high levels of
16:Form of mass wasting
966:2001EEGeo...7..221H
922:10.1038/nature06313
914:2007Natur.450..541T
884:2006GSAB..118.1125S
878:(9–10): 1125–1148.
855:2011JGRF..116.4019K
795:1997AREPS..25...85I
679:1977JGSoc.134..293D
638:Talling et al. 2007
557:on 22 December 2015
440:, pp. 170, 185
329:submarine landslide
1032:list by death toll
825:10.1002/jgrf.20148
204:The Vargas tragedy
120:
38:
36:volcanic eruption.
1442:Natural disasters
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1396:Geomagnetic storm
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1106:Soil liquefaction
1028:Natural disasters
908:(7169): 541–544.
310:
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241:Mudflow geography
148:Sidoarjo mud flow
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1328:Tropical cyclone
1322:Tornado outbreak
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1124:Pyroclastic flow
1116:Volcano eruption
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892:10.1130/B25902.1
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819:(4): 2190–2207.
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751:, archived from
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122:Heavy rainfall,
44:, also known as
34:Mount St. Helens
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1437:Landslide types
1432:Weather hazards
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1296:Cyclonic storms
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946:Further reading
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755:on 27 July 2014
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391:Osceola Mudflow
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335:By volume, the
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347:Areas at risk
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341:Agulhas slide
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267:This section
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229:of hillslope
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1386:Impact event
1374:Astronomical
1308:Thunderstorm
1303:Bomb cyclone
1167:Hydrological
1136:Volcanic ash
1101:Seismic risk
1066:
1049:Mass wasting
957:
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871:
846:
842:
816:
812:
786:
782:
769:
757:, retrieved
753:the original
732:
728:
710:(1): 46–62.
707:
703:
670:
666:
645:
633:
621:. Retrieved
617:ScienceDaily
616:
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559:. Retrieved
555:the original
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457:
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421:
416:, p. 28
405:
370:Areas where
350:
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276:Please help
271:verification
268:
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140:debris flows
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93:
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74:mud failures
73:
69:
67:
63:debris flows
54:mass wasting
49:
45:
41:
39:
25:
1401:Solar flare
1287:Megadrought
1247:Temperature
1220:Megatsunami
1199:Storm surge
1194:Flash flood
1072:Debris flow
773:. Draft of
650:Dingle 1977
623:21 February
561:16 December
452:, p. 4
374:is directed
322:Spirit Lake
189:Los Angeles
128:groundwater
112:Puerto Rico
89:jökulhlaups
85:pyroclastic
1426:Categories
1082:Earthquake
1040:Geological
729:Landslides
659:References
385:Quick clay
318:Washington
290:April 2015
132:landslides
1411:Hypernova
1406:Supernova
1354:Firestorm
1269:Heat wave
1264:Ice storm
1259:Cold wave
1062:Avalanche
1057:Landslide
833:130762677
695:129229469
398:Citations
221:Landslide
200:Venezuela
178:avalanche
110:, Ponce,
1361:ARkStorm
1349:Wildfire
1254:Blizzard
1154:Sinkhole
930:18033295
749:38328696
379:See also
209:evacuate
159:sediment
124:snowmelt
70:mudslips
50:mud flow
46:mudslide
1344:Derecho
1318:Tornado
1279:Drought
1215:Tsunami
1067:Mudflow
962:Bibcode
938:4373921
910:Bibcode
880:Bibcode
851:Bibcode
791:Bibcode
759:16 July
675:Bibcode
187:around
174:viscous
144:erosion
42:mudflow
936:
928:
902:Nature
831:
747:
693:
619:. 2007
196:Vargas
163:debris
136:Floods
81:lahars
1337:Other
1208:Other
1175:Flood
1129:Lahar
934:S2CID
829:S2CID
745:S2CID
691:S2CID
339:(the
185:hills
161:or a
155:grain
108:Tibes
1312:Hail
1180:List
1087:List
926:PMID
761:2014
625:2021
563:2015
138:and
58:dirt
970:doi
918:doi
906:450
888:doi
876:118
859:doi
847:116
821:doi
817:118
799:doi
737:doi
712:doi
683:doi
671:134
280:by
48:or
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