Geological Hazard

Question 1

Causes permanent deformation as a result of the downward and outward movements of large volumes of soil and/or rock down slopes under the influence of the force of gravity.

Answer 1

Landslide

Question 2

happen when the top layer of soil begins to slide down.

Answer 2

Retrogressive Landslide

Question 3

are landslides that have been at smaller area at a time. This is considered as catastrophic compared to landslide that cover large areas.

Answer 3

Piecemeal Landslide

Question 4

happen when the area of a previous landslide incident is disturbed, which results into the reactivation of another landslide.

Answer 4

Reactivated Landslide

Question 5

are also common where the rock below the land surface is carbonate rock, salt beds, or rocks that can actually be dissolved by groundwater circulating through them.

As the rock dissolves, spaces and caverns develop underground. Sinkholes also occur in sandstone and quartzite terrains (USGS Water Science, Dec, 9,2016)

Answer 5

Sinkholes

Question 6

Using holes have been correlated to land- use practices, specially from groundwater pumping and from construction and development practices. Sinkholes can also form when natural water-drainage patterns are change and new water-diversion system are developed.

Answer 6

Human induced sinkholes

Question 7

Happen when a cavity is formed due to the erosion of soluble rock and carbonate.

Answer 7

Dissolution sinkholes

Question 8

When a large material covers a soluble rock and feels the voids of the rock and leads to the erosion of the sediment downward resulting to small depressions which vary in depth and length.

Answer 8

Cover-Subsidence Sinkholes

Question 9

Happens when a clay material covers a layer of carbonate rock.

Answer 9

Cover-Collapse Sinkholes