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Landslide VulnerabilityThe degree of loss resulting from the occurrence of a landslide of a given magnitude (Varnes, 1984)LandslipA synonym for “landslide” – the term “Landslip” no longer in much usageMass MovementMovement of a portion of the land surface, usually downslope – a general descriptive termMoraineA mound, ridge, or other distinct accumulation of unsorted, unstratified glacial drift deposited by (former) icesheets and glaciersMudFine-grained soils dominated by material of clay to sand-size, in a wet condition. < 2mm in diameterOrogenyThe process of the formation of mountains and more specifically the process by which structures in fold-belt mountains wereformed – folding, thrusting, faultingPeriglacialAn environment in which frost action is an important factor, or phenomena induced by a periglacial climate beyond the periphery ofthe icesheetPermafrostAny soil or subsoil occurring in arctic, sub-arctic, or alpine regions which has been frozen continuously for a long timeQuaternaryThe upper system of the Cenozoic Era beginning 2.3 million years ago and which forms the current period of geological time. It is madeup of the Pleistocene (Ice Age) and the Holocene (Postglacial ) EpochsRaised BogAn accumulation of peat with its greatest thickness being at the centre giving it a convex-upward surface. They are found in themidlands of Ireland and are principally composed of moss peatRaster imageAn image composed of a rectangular grid of pixels. Each pixel contains a defined value about its colour, size, and location in theimage.RegolithThe layer of fragmented and unconsolidated rock material overlying the bedrockScreeRock fragments, usually coarse and angular, derived from and lying at the base of cliffs or very steep slopesShear StrengthThe internal resistance of a body to shear stress, typically including a frictional part and a part independent of friction called cohesionSlickensidesA lineated fault or slip surface, having groove lineations which may indicate the direction of slippage on the surfaceSlideA mass movement of earth material under shear stress along one or several surfaces. The movement may be rotational or planar(translational)SolifluctionThe slow viscous downslope flow of waterlogged soil, usually in areas underlain by frozen ground ie. in periglacial areasSpreadThe dominant movement in a spreading landslide is lateral extension due to shearing or tensional fracturesTalusSee “Scree”TillLargely unsorted and unstratified material deposited directly underneath a glacier and consisting of a heterogeneous mixture of clay,silt, sand, gravel, and bouldersToppleA mass movement that consists of the forward rotation of units of rock about a pivot point under the force of gravityTsunamiA gravitational seawave produced by any large-scale, short duration disturbance of the sea-floor due to an earthquake, sea floorsubsidence or a volcanic eruption98