Geologic Hazard

24問 • 2年前

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are natural phenomena that cause major problems around the world

Geologi Hazards

ground movement on a sloping terrain. It does not happen on flat ground because of the angle on the ground, gravity induces the land to move downward.

landslide

types of landslide

1. Soil Creep Landslide 2.Slumping Landslide 3. Debris Flow Landslide 4. Rock Fall landslides

is a very slow downslope movement of particles that occurs in every slope covered with loose, weathered material (Britannica dictionary).

soil creep landslide

is a downward movement of rock debris, usually the consequence of removal of buttressing earth at the foot of a slope of unconsolidated mater

slumping landslide

happens when the slope becomes saturated with water, this then triggers a landslide of water-soaked mass of rock and soil that slides down the slope.

debris flow landslide

are sudden slides caused by heavy rain the rock on the slope loosens and then slides down the slope.

rock fall landslide

is a topographic depression created when groundwater dissolves the underlying limestone bedrock.

sinkhole

sinkhole is Often known as

sink or doline

sinkhole characteristics

● occur in areas where the soil foundation is made of soft minerals and rocks such as limestone, salt beds, or any acidic rocks. ● The depth of sinkholes ranges from a couple of meters to several mile deep.

It develops suddenly (over an hour period) thus, causing catastrophic damage.

cover collapse sinkhole

It gradually grows where the sediment covers are permeable and contain sand.

cover subsidence sinkhole

It occurs in areas where calcareous is exposed on the ground or where thin layers of soil and permeable sand are also covered. Limestone or dolomite dissolution is most intense when the water first reaches the rock surface.

dissolution sinkhole

Such types of sinks may be caused by various human activities, including groundwater pumping and building.

artificial sinkhole

induces the land to move downward. It

gravity

It does not happen on flat ground because

the angle on the ground

Structures that are built on blank, a high vulnerability to landslide hazards especially during heavy rains.

steep- slope mountains

.... are distinguished by a high susceptibility to rainfall-induced landslide hazards.

steep slope, dense population and denuded terrain

may saturate the topsoil and the bedrock, weakening the soil base of buildings or structures.

Long or regular rain

quickly destroy these buildings and communities, giving way to landslides, mudslides, or mudflows.

A heavy downpour of rain

Water from the rainfall seeps underneath the soil through the

cracks and fissures.

is a natural agent for erosion.

water

It is aggravated by rain because water is a natural agent for erosion. If rain or any source of water frequently flows down a sloping area, the gravitational descent of loosened soil makes it possible for

landslide to occur

Types of Sinkholes

1. Cover Collapse Sinkhole 2. Cover Subsidence Sinkhole 3. Dissolution Sinkhole 4. Artificial Sinkhole

MODULE 3a

charish · 23問 · 2年前

MODULE 3a