Quick clay

Quick clay, also known as Leda clay and Champlain Sea clay in Canada, is any of several distinctively sensitive glaciomarine clays found in Canada, Norway, Russia, Sweden, Finland, the United States and other locations around the world. The clay is so unstable that when a mass of quick clay is subjected to sufficient stress, the material behavior may change from that of a particulate material to that of a fluid.

Quick clay has a remolded strength which is much less than its strength upon initial loading. This is caused by its highly unstable clay particle structure.

Quick clay is typically originally deposited in a marine environment. In that environment, the positive charge of cations (such as Na2+) was able to bind clay particles with negative surface charge (typically silicates SOn-
) by balancing charge in the double layer. When the clay became uplifted and was no longer subjected to salt water conditions, rainwater infiltrated these clays and washed away the salts that allowed these clay particles to remain in a stable structure.

With shear stress, the lack of counterbalancing charge from salts in the quick clay results in clay particle repulsion and realignment of clay particles to a structure that is extremely weak and unstable. Quick clay regains strength rapidly, however, when salt is added, which allows clay particles to form complexes with one another.

Quick clay is found only in northern countries, such as Russia, Canada, Norway, Sweden, and Finland, and in Alaska, United States since they were glaciated during the Pleistocene epoch. In Canada, the clay is associated primarily with the Pleistocene-era Champlain Sea, in the modern Ottawa Valley, the St. Lawrence Valley, and the Saguenay River regions.[1]

Quick clay has been the underlying cause of many deadly landslides. In Canada alone, it has been associated with more than 250 mapped landslides. Some of these are ancient, and may have been triggered by earthquakes.[2]

Formation of quick clay

At the height of the past glaciation (about 20,000 years ago), the land was 'pushed' down by the weight of the ice (isostatic depression). All of the ground-up rock was deposited in the surrounding ocean, which had penetrated significantly inland. The loose deposition of the silt and clay particles in the marine environment, allowed an unusual flocculation to take place. Essentially, this formed a strongly bonded soil skeleton, which was 'glued' by highly mobile sea-salt ions.[3]

At this point, there was only the formation of very strong marine clay, which is found all over the world and highly stable, but with its own unique geotechnical problems. When the glaciers retreated, the land mass rose (post-glacial rebound), the clay was exposed, and formed the soil mass for new vegetation. The rainwater in these northern countries was quite aggressive to these clays, perhaps because it was softer (containing less calcium), or the higher silt content allowed more rainwater and snowmelt to penetrate. The final result was that the ionic 'glue' of the clay was weakened, to give a weak, loose soil skeleton, enclosing significant amounts of water (high sensitivity with high moisture content).

Quick clay deposits are rarely located directly at the ground surface, but are typically covered by a normal layer of topsoil. While this topsoil can absorb most normal stresses, such as normal rainfall or a modest earth tremor, a shock that exceeds the capacity of the topsoil layer — such as a larger earthquake, or an abnormal rainfall which leaves the topsoil fully saturated so that additional water has nowhere to permeate except into the clay — can disturb the clay and initiate the process of liquefaction.


Because the clay layer is typically covered with topsoil, a location which is vulnerable to a quick clay landslide is usually identifiable only by soil testing, and is rarely obvious to a casual observer. Thus human settlements and transportation links have often been built on or near clay deposits, resulting in a number of notable catastrophes:

  • In 1702, a landslide destroyed almost all traces of the medieval town Sarpsborg. 15 people and 200 animals were killed.
  • On 19 May 1893, a landslide in Verdal, Norway, killed 116 people and destroyed 105 farms. It left a crater several kilometers in diameter.
  • The most disastrous such landslide to affect North America occurred in 1908, when a slide into the frozen Du Lièvre River propelled a wave of ice-filled water into Notre-Dame-de-la-Salette, Quebec causing the loss of 33 lives and the destruction of 12 homes.
  • In 1955, a landslide affected part of the downtown of Nicolet, Quebec, causing $10 million in damages.[1]
  • On May 4, 1971, 31 lives were lost when 40 homes were swallowed in a retrogressive flowslide in Saint-Jean-Vianney, Quebec,[4] resulting in the relocation of the entire town when the government declared the area uninhabitable due to the presence of Leda clay.
  • The experience of Saint-Jean-Vianney contributed to the abandonment of the town of Lemieux, Ontario in 1991, after a 1989 study showed it was also located on the same type of clay along the South Nation River. In 1993, those findings were borne out when the town's abandoned main street was swallowed by a massive 17 hectare landslide.[5]
  • Another famous flow of quick clay at Rissa, Norway, in 1978 caused about 33 hectares (82 acres) of farmland to liquefy and flow into the lake Botn over a few hours, with the loss of one life. The Rissa slide was well recorded by local citizens and a documentary film was made about it in 1981.[6]
  • On May 11, 2010, quick clay took the lives of a family living in Saint-Jude, Quebec, when the land their house was built on suddenly tumbled down toward the Salvail River. The landslide was so sudden that the family members died where they sat; they had been watching an ice hockey game on television.[7] The slide took out a portion of rural road which took a year to reinstate.[8]
  • On 2 February 2015, a landslide collapsed a pillar on the Skjeggestad Bridge. The landslide was caused by nearby earthworks.

These landslides are retrogressive, meaning they usually start at a river, and progress upwards at slow walking speed. They have been known to penetrate kilometers inland, and consume everything in their path.[1]

In modern times, areas known to have quick clay deposits are commonly tested in advance of any major human development. It is not always possible to entirely avoid building on a quick clay site, although modern engineering techniques have found technical precautions which can be taken to mitigate the risk of disaster. For example, when Ontario's Highway 416 had to pass through a quick clay deposit near Nepean, lighter fill materials such as polystyrene were used for the road bed, vertical wick drains were inserted along the route and groundwater cutoff walls were built under the highway to limit water infiltration into the clay.[9]


  1. ^ a b c Perreaux, Les (13 May 2010). "Residents seek reassurance in wake of deadly slide". The Globe and Mail. Montreal. Archived from the original on 15 May 2010. Retrieved 2016-07-21.
  2. ^ "Landslides". Geoscape Ottawa-Gatineau. Natural Resources Canada. 7 March 2005. Archived from the original on 24 October 2005. Retrieved 2016-07-21.
  3. ^ Rankka, Karin; Andersson-Sköld, Yvonne; Hultén, Carina; Larsson, Rolf; Leroux, Virginie; Dahlin, Torleif (2004). "Quick clay in Sweden" (PDF). Report No. 65. Swedish Geotechnical Institute. Archived from the original (PDF) on 4 April 2005. Retrieved 20 April 2005.
  4. ^ Wallechinsky, David; Wallace, Irving (1981). "Landslide in Saint-Jean-Vianney, Canada in 1971". Trivia-Library.com. Archived from the original on 8 July 2008. Retrieved 27 January 2008.
  5. ^ "Lemieux, Ottawa – Valley Ghost Town". Canadian Geographic Magazine. October 2005. Archived from the original on 10 July 2010. Retrieved 22 September 2007.
  6. ^ BFI | Film & TV Database | The RISSA LANDSLIDE (1981)
  7. ^ "Family dead in basement after sinkhole ate home". CNN, May 12, 2010.
  8. ^ Article, TVA, July 13, 2011
  9. ^ "Conquering the Leda clay" Archived October 3, 2006, at the Wayback Machine., Ontario Ministry of Transportation.

External links

  • Rissa Landslide, by University of Washington: short synopsis with link to video clips
1893 in Norway

Events in the year 1893 in Norway.

Botn (Trøndelag)

Botn (also called Rissa-Botn) is an inland fjord in the Rissa area of the municipality of Indre Fosen in Trøndelag county, Norway. It flows through a short, small river into the Sundsbukta, a small bay off the Trondheimsfjorden. The village of Årnset lies on the north shore of Botn.


Clay is a finely-grained natural rock or soil material that combines one or more clay minerals with possible traces of quartz (SiO2), metal oxides (Al2O3 , MgO etc.) and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure. Clays are plastic due to particle size and geometry as well as water content, and become hard, brittle and non–plastic upon drying or firing. Depending on the soil's content in which it is found, clay can appear in various colours from white to dull grey or brown to deep orange-red.

Although many naturally occurring deposits include both silts and clay, clays are distinguished from other fine-grained soils by differences in size and mineralogy. Silts, which are fine-grained soils that do not include clay minerals, tend to have larger particle sizes than clays. There is, however, some overlap in particle size and other physical properties. The distinction between silt and clay varies by discipline. Geologists and soil scientists usually consider the separation to occur at a particle size of 2 µm (clays being finer than silts), sedimentologists often use 4–5 μm, and colloid chemists use 1 μm. Geotechnical engineers distinguish between silts and clays based on the plasticity properties of the soil, as measured by the soils' Atterberg limits. ISO 14688 grades clay particles as being smaller than 2 μm and silt particles as being larger.

Mixtures of sand, silt and less than 40% clay are called loam. Loam makes good soil and is used as a building material.

Hell–Sunnan Line

The Hell–Sunnan Line (Norwegian: Hell–Sunnanbanen) is a 105-kilometer-long (65 mi) railway line between Hell, Stjørdal and Sunnan, Steinkjer in Nord-Trøndelag, Norway. The name is no longer in official use and the line is now considered part of the Nordland Line. The Hell–Sunnan Line branches from the Meråker Line at Hell and runs on the east shore of the Trondheimsfjord passing through the municipalities of Stjørdal, Levanger, Verdal, Inderøy and Steinkjer.

The Norwegian State Railways (NSB) started construction in 1899 and the first part of the line, from Hell to Stjørdalshalsen, opened on 1 February 1902. The railway opened to Levanger on 29 October 1902, to Verdalsøra on 1 November 1904 and to Sunnan on 15 November 1905. Sunnan was chosen as terminus because of its location on the southern end of the lake of Snåsavatnet. The line was further extended to Snåsa in 1926, after which it has been classified as part of the Nordland Line. The railway is the most heavily trafficked non-electrified line in Norway, with the Trøndelag Commuter Rail running south of Steinkjer. It is also used by intercity passenger and freight trains.

Index of soil-related articles

This is an index of articles relating to soil.

Indre Fosen

Indre Fosen is a municipality in Trøndelag county, Norway. It is located in the traditional district of Fosen. The administrative centre of the municipality is the village of Årnset. Other villages in Indre Fosen include Askjem, Dalbygda, Hasselvika, Husbysjøen, Leira, Leksvik, Råkvåg, Rørvika, Seter, Stadsbygd, and Vanvikan. The Norwegian County Road 755 runs through the municipality.

The 1,052-square-kilometre (406 sq mi) municipality is the 98th largest by area out of the 422 municipalities in Norway. Indre Fosen is the 114th most populous municipality in Norway with a population of 10,108. The municipality's population density is 10.2 inhabitants per square kilometre (26/sq mi) and its population has increased by 2.6% over the last decade.


Karaburma (Serbian Cyrillic: Карабурма) is an urban neighborhood of the municipality of Palilula, Belgrade, Serbia. As of 2002, it has a population of 55,343 inhabitants.

Kolsås Line

The Kolsås Line (Norwegian: Kolsåsbanen) is 12.1-kilometer (7.5 mi) line of the Oslo Metro. It branches off from the Røa Line at Smestad Station and runs through western Oslo and Bærum to Kolsås Station. It serves the neighborhoods of Ullernåsen, Øraker, Jar, Bekkestua, Haslum, Gjettum and Kolsås. It is served by Line 3 of the metro at a 15-minute headway. The section from Jar to Bekkestua is built as a dual system with overhead wires, allowing Line 13 of the Oslo Tramway to continue from the Lilleaker Line to Bekkestua every ten minutes.

The Kolsås Line was built as an extension of the Lilleaker Line. It had been built to Lilleaker in 1919. The line was extended to Avløs on 1 July 1924, and the line was extended to Kolsås on 1 January 1930. The line was initially owned by Bærumsbanen, which was bought by Oslo Sporveier in 1934. A connection to the Røa Line opened on 15 June 1942, allowing the line access to the Common Tunnel. At this point the section from Sørbyhaugen to Kolsås was designated the Kolsås Line, while the section from Jar to Skøyen was retained as the Lilleaker Line. T1300 trains of the metro were introduced in 1982 and from 1995 it was linked with the eastern metro lines. The line was closed for upgrades to metro standard in 2006. It reopened in eight stages from 2008 to 2014. There are plans to extend the line to Rykkinn, Bærums Verk and Sandvika, although none of these have political priority.


The term landslide or, less frequently, landslip, 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 which 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.

Landslide (novel)

Landslide is a first-person narrative novel written by English author Desmond Bagley, and was first published in 1967.

List of landslides

This list of landslides is a list of notable landslides and mudflows divided into sections by date and type. This list is very incomplete as there is no central catalogue for landslides, although some for individual countries/areas do exist. Volumes of landslides are recorded in the scientific literature using cubic kilometres (km3) for the largest and millions of cubic metres (normally given the non-standard shortening of MCM) for most events.

Marine clay

Marine clay is a type of clay found in coastal regions around the world. In the northern, deglaciated regions, it can sometimes be quick clay, which is notorious for being involved in landslides.

Marine clay is a particle of soil that is dedicated to a particle size class, this is usually associated with USDA’s classification with sand at 0.05mm, silt at 0.05-.002mm and clay being less than 0.002 mm in diameter. Paired with the fact this size of particle was deposited within a marine system involving the erosion and transportation of the clay into the ocean.

Soil particles become suspended when in a solution with water, with sand being affected by the force of gravity first with suspended silt and clay still floating in solution. This is also known as turbidity, in which floating soil particles create a murky brown color to a water solution. These clay particles are then transferred to the abyssal plain in which they are deposited in high percentages of clay. A soil is only considered a clay if it has above 55% total clay content. This is due to the way in which the clay reacts to things like water, heat and other chemicals.

Once the clay is deposited on the ocean floor it can change its structure through a process known as flocculation, process by which fine particulates are caused to clump together or floc. These can be either edge to edge flocculation or edge to face flocculation. Relating to individual clay particles interacting with each other. Clays can also be aggregated or shifted in their structure besides being flocculated.

Clay particles can self-assemble into various configurations, each with totally different properties.

This change in structure to the clay particles is due to a swap in cations with the basic structure of a clay particle. This basic structure of the clay particle is known as a silica tetrahedral or aluminum octahedral. They are the basic structure of clay particles composing of one cation, usually silica or aluminum surrounded by hydroxide anions, these particles form in sheets forming what we know as clay particles and have very specific properties to them including micro porosity which is the ability of clay to hold water against the force of gravity, shrink swell capacity and absorption capabilities.

When clay is deposited in the ocean, the presence of excess ions in seawater causes a loose, open structure of the clay particles to form, a process known as flocculation. Once stranded and dried by ancient changing ocean levels, this open framework means that such clay is open to water infiltration. Construction in marine clays thus presents a geotechnical engineering challenge. Where clay overlies peat, a lateral movement of the coastline is indicated and shows a rise in relative sea level

Swelling of marine clay has the potential to destroy building foundations in only a few years. Due to the changes in climatic conditions on the construction site, the pavement constructed on the marine clay (as subgrade) will have less durability and requires lot of maintenance cost. Some simple precautions, however, can reduce the hazard significantly.

The swapping of this positive cation with another is what makes different types of clays including Kaolinite, montmorillonite, smectite and illite. This happens in marine clays due the fact the oceans water is high in solution with cations making it very easy to overcome the clays negative net charge and swap the clays cation with a less positive one. These marine clays can be what are known as quick clays, which are notorious for its erosive properties. A great example of these quick clays is in the pacific northwest. They are known as blue goo which is a mix of clay and mélange (greenstone, basalt, chert, shale, sandstone, schists. uplifted through the accretionary wedge). These quick clays have a very high-risk factor associated with them if they are built upon, as they are very unstable due to the fact that liquefaction happens when it becomes saturated and literally flows, causing mass wasting events to happen. Other marine clays are used all around the world for many different uses, such as ceramics, building material, including adobe. Clay layers in soils which can be used as an impermeable layer are very important for dumps or chemical spills as they have a very high absorption capacity for heavy metals. For these clays to be available for human use they must have been eroded deposited on the ocean floor and then uplifted through means of tectonic activity to bring it to land.

During the construction of Marina Barrage in Singapore, marine clay was found at the site. Since marine clay was the cause of the Nicoll Highway collapse years previous, the construction team removed all the marine clay to ensure the stability of Marina Barrage. Later on, they found marine clay mixed with seawater even in the deeper underground.

Geotechnical problems posed by marine clay can be handled by various ground improvement techniques. Marine clay can be densified by mixing it with cement or similar binding material in specific proportions. Marine clay can be stabilised using wastes of various industries like porcelain industry and tree-cutting industries. This method is usually adopted in highways where marine clay is used as a subgrade soil.


A mudflow or mud flow is a form of mass wasting involving "very rapid to extremely rapid surging flow" of debris that has become partially or fully liquified by the addition of significant amounts of water to the source material.Mudflows contain a significant proportion of clay, which makes them more fluid than debris flows; thus, they are able to travel farther and across lower slope angles. Both types are generally mixtures of various kinds of materials of different sizes, which are typically sorted by size upon deposition.Mudflows are often called mudslides, 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 flow slides.Other types of mudflows include lahars (involving fine-grained pyroclastic deposits on the flanks of volcanoes) and jökulhlaups (outbursts from under glaciers or icecaps).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.

Rissa, Norway

Rissa is a former municipality in the old Sør-Trøndelag county in Norway in the Fosen region. The municipality existed from 1860 until its dissolution on 1 January 2018 when it became part of the municipality of Indre Fosen in Trøndelag county. The administrative centre of the municipality was the village of Årnset. Other villages in the municipality included Askjem, Hasselvika, Husbysjøen, Rørvika, Råkvåg, and Stadsbygd.

The 621-square-kilometre (240 sq mi) municipality was the 179th largest by area out of the then 426 municipalities in Norway. Rissa was the 158th most populous municipality in Norway with a population of 6,628. The municipality's population density was 11.3 inhabitants per square kilometre (29/sq mi) and its population had increased by 4.1% over the last decade.

Skjeggestad Bridge

Skjeggestad Bridge (Norwegian: Skjeggestadbrua) is the name of two parallel highway bridges on European route E18 in Holmestrand municipality, Vestfold, Norway.

On 2 February 2015 the southbound bridge partially collapsed. No one was injured and both bridges were closed after collapse. The reason for the collapse was a landslide in the quick clay surrounding a support pillar. The southbound lane was fully destroyed in controlled explosive demolitions on 21 February and 25 March 2015.

The northbound lane was repaired and reopened to two-way traffic on 26 June 2015.

The southbound lane was partially reopened on 1 July and fully operational on 4 July 2016, 17 months after the collapse.

Soil liquefaction

Soil liquefaction occurs when a saturated or partially saturated soil substantially loses strength and stiffness in response to an applied stress such as shaking during an earthquake or other sudden change in stress condition, in which material that is ordinarily a solid behaves like a liquid.

In soil mechanics, the term "liquefied" was first used by Allen Hazen in reference to the 1918 failure of the Calaveras Dam in California. He described the mechanism of flow liquefaction of the embankment dam as:

If the pressure of the water in the pores is great enough to carry all the load, it will have the effect of holding the particles apart and of producing a condition that is practically equivalent to that of quicksand… the initial movement of some part of the material might result in accumulating pressure, first on one point, and then on another, successively, as the early points of concentration were liquefied.

The phenomenon is most often observed in saturated, loose (low density or uncompacted), sandy soils. This is because a loose sand has a tendency to compress when a load is applied. Dense sands by contrast tend to expand in volume or 'dilate'. If the soil is saturated by water, a condition that often exists when the soil is below the water table or sea level, then water fills the gaps between soil grains ('pore spaces'). In response to soil compressing, the water pressure increases and the water attempts to flow out from the soil to zones of low pressure (usually upward towards the ground surface). However, if the loading is rapidly applied and large enough, or is repeated many times (e.g. earthquake shaking, storm wave loading) such that the water does not flow out before the next cycle of load is applied, the water pressures may build to the extent that it exceeds the force (contact stresses) between the grains of soil that keep them in contact. These contacts between grains are the means by which the weight from buildings and overlying soil layers is transferred from the ground surface to layers of soil or rock at greater depths. This loss of soil structure causes it to lose its strength (the ability to transfer shear stress), and it may be observed to flow like a liquid (hence 'liquefaction').

Although the effects of liquefaction have been long understood, engineers took more notice after the 1964 Niigata earthquake and 1964 Alaska earthquake. It was a major factor in the destruction in San Francisco's Marina District during the 1989 Loma Prieta earthquake, and in Port of Kobe during the 1995 Great Hanshin earthquake. More recently liquefaction was largely responsible for extensive damage to residential properties in the eastern suburbs and satellite townships of Christchurch, New Zealand during the 2010 Canterbury earthquake and more extensively again following the Christchurch earthquakes that followed in early and mid-2011. On 28th September 2018, an earthquake of 7.5 magnitude hit the Central Sulawesi province of Indonesia. Resulting soil liquefaction buried the suburb of Balaroa and Petobo village in 3 meters deep mud. The government of Indonesia is considering designating the two neighborhoods of Balaroa and Petobo, that have been totally buried under mud- as mass graves.The building codes in many countries require engineers to consider the effects of soil liquefaction in the design of new buildings and infrastructure such as bridges, embankment dams and retaining structures.

Tyholt Tunnel

The Tyholt Tunnel is a 2,785-meter (9,137 ft) railway tunnel which runs between Lerkendal and Lademoen on the Stavne–Leangen Line in Trondheim, Norway. The line takes its name for passing under the neighborhood of Tyholt and only sees regular freight traffic.

Construction began by the Wehrmacht during the German occupation of Norway from 1940 to 1945, but the project was never completed. The Norwegian State Railways (NSB) resumed the work in the 1950s. Part of the tunnel was built using cut-and-cover, part using a tunneling shield and most of it was blasted. It opened on 1 June 1957.


Verdal is a municipality in Trøndelag county, Norway. It is part of the Innherad region. The administrative centre of the municipality is the town of Verdalsøra. Other villages in the municipality include Forbregd/Lein, Lysthaugen, Stiklestad, Trones, Vera, Vinne, and Vuku.

The 1,548-square-kilometre (598 sq mi) municipality is the 48th largest by area out of the 422 municipalities in Norway. Verdal is the 80th most populous municipality in Norway with a population of 14,849. The municipality's population density is 10 inhabitants per square kilometre (26/sq mi) and its population has increased by 6.4% over the last decade.

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