Geological hazards: Natural variation and human action may lead to changes in the geological environment or geological body, and when such changes reach a certain level, the consequences will cause harm to human beings and society, which are called geological hazards, such as collapse, landslide, mudflow, ground fracture, ground subsidence, ground collapse, rock explosion, pit sudden water, sudden mud, sudden gas, coal seam natural, loess wet sink, rock expansion, sand liquefaction, land freezing and thawing, soil erosion, land desertification and swamp, soil salinization, as well as earthquakes, volcanoes, geothermal damage, etc.

Classification of geological hazards: There are different perspectives and standards, and it is very complicated. In terms of their causes, geological hazards mainly caused by natural variation are called natural geological hazards; those mainly induced by human action are called man-made geological hazards. In terms of the speed of change of geological environment or geological body, it can be divided into two categories: sudden-onset geological disasters and slow-onset geological disasters. The former, such as collapse, landslide, mudslide, etc., are customary geological disasters in a narrow sense; the latter, such as soil erosion, land desertification, etc., are also called environmental geological disasters. According to the geographical or geomorphological features of the area where the geological disasters occur, they can be divided into mountain geological disasters, such as landslides, landslides, mudflows, etc., and plain geological disasters, such as ground subsidence, and so on.

Introduction of main types

Landslide: It is a phenomenon that the rock on a slope slides downward as a whole along a certain weak surface or weak zone under the action of gravity for some reason.

Landslide: It is a geological phenomenon in which the rock and soil bodies on a steeper slope suddenly fall away from the parent body under the action of gravity and roll and accumulate at the foot of the slope.

Debris flow: It is a natural phenomenon unique to mountainous areas. It is a special flood with a large amount of sediment, rocks and other solid material conditions formed due to precipitation. Identification: asymmetrical and uneven length of the midstream ditch; formation of plunging water in the ditch; formation of multi-level terraces, etc.

Ground collapse: It is a natural phenomenon in which the surface rock and soil bodies sink downward under the action of natural or man-made factors and form a collapse pit on the ground.

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