What is soil flow?

Soil Flow is flow of completely saturated soil with water where individual soil particles move easily over one another and over the underlying rock. Landslides are very rapid movement of mass of soil or rock in steep slopes such as in mountainous areas.

What is the meaning of soil flow?

Definition. Soil water flow is conditioned by the existence of a gradient of the total potential of soil water in both, the soil fully saturated by water (saturated flow) as well as in soil not fully saturated by water (unsaturated flow).

What is soil creep and soil flow?

Soil creep is the slow downward movement of rock and soil down a low grade or gentle slope. Soil flow is the rapid movement or flow of water containing large amount of suspended particles and silt.

What type of flow is assumed to occur in soils?

Generally three types of water movement within the soil are recognized –saturated flow, unsaturated flow and water vapour flow (Fig. 23.1). Water in the liquid phase moves through the water filled pores within the soil (saturated condition) under the influence of gravitational force.

What is the difference between landslides and soil creep?

Mud and debris flows are very fast landslides that are likely to kill anyone unfortunate enough to be caught in their path, as they can reach speeds that exceed 32 kph (20 mph). The slowest kind of landslide is known as creep. When clay in the soil on a hillside absorbs water, it will expand, causing the soil to swell.

Is mudflow a landslide?

Landslides are caused by disturbances in the natural stability of a slope. They can accompany heavy rains or follow droughts, earthquakes, or volcanic eruptions. Mudslides develop when water rapidly accumulates in the ground and results in a surge of water-saturated rock, earth, and debris.

What called landslide?

A landslide is defined as the movement of a mass of rock, debris, or earth down a slope. Landslides are a type of “mass wasting,” which denotes any down-slope movement of soil and rock under the direct influence of gravity.

Is landslide a calamity?

They are a deadly and unpredictable type of natural disaster and are the leading reason for landslides or Rock falls occurring worldwide. Loose soil, rocks and boulders can easily be dislodged from hilly areas and allowed to move downhill when the violent shaking of the ground transpires.

What are the 4 types of landslides?

Landslides are part of a more general erosion or surficial pro- cess known as mass wasting, which is simply the downslope movement of earth or surface materials due to gravity. They are classified into four main types: fall and toppling, slides (rotational and translational), flows and creep.

What is rock mass movement?

mass movement, also called Mass Wasting, bulk movements of soil and rock debris down slopes in response to the pull of gravity, or the rapid or gradual sinking of the Earth’s ground surface in a predominantly vertical direction.

How is a slump formed?

A slump is a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope. Movement is characterized by sliding along a concave-upward or planar surface.

What are fastest types of sediment flows?

Mudflows – these are a highly fluid, high velocity mixture of sediment and water that has a consistency ranging between soup-like and wet concrete. They move at velocities greater than 1 km/hr and tend to travel along valley floors.

What are 4 types of mass movement?

There are four different types of mass movement:

• Rockfall. Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.
• Mudflow. Saturated soil (soil filled with water) flows down a slope.
• Landslide. Large blocks of rock slide downhill.
• Rotational slip. Saturated soil slumps down a curved surface.

What causes a rock slide?

High precipitation, natural erosion, temperature variations or extreme stresses such as earthquakes can trigger rock slides or rock flows. When infrastructure and buildings are hit, the results are often catastrophic.

What is fall landslide?

Falls are landslides that involve the collapse of material from a cliff or steep slope. Falls usually involve a mixture of free fall through the air, bouncing or rolling. A fall-type landslide results in the collection of rock or debris near the base of a slope.

What is the difference between mudflow and landslide?

A landslide is a mass movement of soil, rocks or other debris down a slope or across the surface of the earth. A mudslide is the large-scale movement of fine particles that are partly liquefied down or along a slope.

What causes a mudflow?

Mudslides occur when a large amount of water causes the rapid erosion of soil on a steep slope. Rapid snowmelt at the top of a mountain or a period of intense rainfall can trigger a mudslide, as the great volume of water mixes with soil and causes it to liquefy and move downhill.

What happens during a mudflow?

A mudflow or mudslide occurs when mud travels down a slope very quickly. Mudflows, which are like giant moving mud pies, happen when lots of water mixes with soil and rock. The water makes the slippery mass of mud flow quickly down.

What is the difference between a mudflow and debris flow?

Debris-fan floodplain means a floodplain that is located at the mouth of a mountain valley tributary stream as such stream enters the valley floor. A mud flow is a geologic phenomenon whereby a wet, viscous fluid mass of fine-to-coarse-grained material flows rapidly and turbulently downslope, usually in a drainageway.

What is landslide and rockfall?

A landslide is the movement of a mass of rock, debris, or earth (soil) down a slope. A rockfall is the action of boulders, rocks or slabs of rock falling or toppling.

What is it called when rocks fall?

Rockfall is the free or bounding fall of rock debris down steep slopes under the influence of gravity.

What causes landslides and rockfalls?

Rockfalls are often caused by erosion of earth around larger rocks that then become loose and fall. Earthquakes can also lead to landslides and rockfalls.

Where do rockfalls happen?

Rockfalls occur where a source of rock exists above a slope steep enough to allow rapid downslope movement of dislodged rocks by falling, rolling, bouncing, and sliding. Rockfall sources include bedrock outcrops or boulders on steep mountainsides or near the edges of escarpments such as cliffs, bluffs, and terraces.

How can we prevent rockfalls?

Structures designed to protect the areas around a slope from falling rocks include mesh or cable nets, barriers and fences, and catchment areas (ditches at the toe of a slope, designed to prevent rockfall from reaching the highway).