Definition in natural science.

Adverse geological phenomena are usually called geological disasters, which are geological events caused by natural geological action and human activities that deteriorate the geological environment, reduce the quality of the environment, directly or indirectly endanger human safety, and cause losses to society and economic construction. A geological disaster is a geological action (phenomenon) formed by natural or human factors that causes damage and loss to human life, property and the environment. Such as collapse, landslide, mudslide, ground crack, ground subsidence, ground collapse, rock explosion, pit sudden water, sudden mud, sudden gas, coal seam spontaneous combustion, loess wet sink, geotechnical expansion, sand liquefaction, land freezing and thawing, soil erosion, land desertification and swamp, soil salinization, as well as earthquake, volcano, geothermal damage, etc.

Defined in the relevant laws and regulations of China.

According to the Regulations on Prevention and Control of Geological Disasters issued by the State Council in 2004, geological disasters, usually refer to disasters caused by geological action that result in the loss of people's lives and properties. Geological disasters can be divided into more than 30 types. Those induced by rainfall, snow melt, earthquake and other factors are called natural geological disasters, and those triggered by engineering excavation, piling, blasting and earth dumping.

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