Landslide

A landslide near Cusco, Peru in 2018.
A NASA model has been developed to look at how potential landslide activity is changing around the world.

The term landslide or less frequently, landslip,[1] refers to several forms of mass wasting that include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable.

Causes

The Mameyes Landslide, in the Mameyes neighborhood of barrio Portugués Urbano in Ponce, Puerto Rico, which buried more than 100 homes, was caused by extensive accumulation of rains and, according to some sources, lightning.

Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This is essentially due to a decrease in the shear strength of the slope material, to an increase in the shear stress borne by the material, or to a combination of the two. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Natural causes of landslides include:

  • saturation by rain water infiltration, snow melting, or glaciers melting;
  • rising of groundwater or increase of pore water pressure (e.g. due to aquifer recharge in rainy seasons, or by rain water infiltration);[2]
  • increase of hydrostatic pressure in cracks and fractures;[2][3]
  • loss or absence of vertical vegetative structure, soil nutrients, and soil structure (e.g. after a wildfire – a fire in forests lasting for 3–4 days);
  • erosion of the toe of a slope by rivers or ocean waves;
  • physical and chemical weathering (e.g. by repeated freezing and thawing, heating and cooling, salt leaking in the groundwater or mineral dissolution);[4][5]
  • ground shaking caused by earthquakes, which can destabilize the slope directly (e.g., by inducing soil liquefaction) or weaken the material and cause cracks that will eventually produce a landslide;[3][6][7]
  • volcanic eruptions;

Landslides are aggravated by human activities, such as:

The landslide at Surte in Sweden, 1950. It was a quick clay slide killing one person.
Other Languages
العربية: انهيار أرضي
asturianu: Argayu
azərbaycanca: Torpaq sürüşməsi
বাংলা: ভূমিধস
Banjar: Rumbih
Bân-lâm-gú: Pang-soaⁿ
беларуская: Апоўзень
беларуская (тарашкевіца)‎: Апоўзень
български: Свлачище
bosanski: Klizište
català: Esllavissada
čeština: Svahový pohyb
dansk: Jordskred
Deutsch: Erdrutsch
eesti: Maalihe
Ελληνικά: Κατολίσθηση
Esperanto: Terglito
euskara: Luizi
ગુજરાતી: ભૂસ્ખલન
한국어: 산사태
հայերեն: Սողանքներ
हिन्दी: भूस्खलन
hrvatski: Klizište
Bahasa Indonesia: Tanah longsor
italiano: Frana
ಕನ್ನಡ: ಭೂಕುಸಿತ
ქართული: მეწყერი
қазақша: Жылжыма
Kreyòl ayisyen: Glisman teren
latviešu: Zemes nogruvums
lietuvių: Nuošliauža
मराठी: भूस्खलन
მარგალური: მენწყერი
Bahasa Melayu: Tanah runtuh
မြန်မာဘာသာ: မြေပြိုခြင်း
Nederlands: Aardverschuiving
नेपाली: भू-क्षय
日本語: 地すべり
norsk: Skred
norsk nynorsk: Jordras
oʻzbekcha/ўзбекча: Togʻ qulashi
polski: Osuwisko
Runa Simi: Lluqlla
русский: Оползень
සිංහල: නායයෑම්
Simple English: Landslide
slovenčina: Zosuv svahu
slovenščina: Zemeljski plaz
српски / srpski: Клизиште
srpskohrvatski / српскохрватски: Klizište
Sunda: Urug
suomi: Maanvyöry
svenska: Jordskred
татарча/tatarça: Шуышма
Türkçe: Heyelan
українська: Зсув ґрунту
اردو: ہبوط ارض
Tiếng Việt: Đất trượt
文言: 山崩
Winaray: Pagparik
吴语: 山体滑坡
粵語: 冧山泥
中文: 山崩