background
China is located in the southeast of Eurasia plate, with complex geological structure. Under the compression of the Pacific plate and the Indian plate, the seismic fault zone is very developed, with a wide range of seismic activity, high intensity and high frequency. An earthquake is simply ground vibration, but the complete explanation should refer to the phenomenon that the energy wave excited from somewhere inside the earth releases energy quickly when it propagates upward to the ground, resulting in ground vibration, shaking or rupture. In other words, the earthquake process includes three stages: energy excitation, energy transmission and energy release. The earthquake precursors that people's senses can directly perceive are called macro precursors of earthquakes, which are referred to as macro precursors for short. Common ones are abnormal water level and water quality, abnormal living habits of animals and plants, abnormal electromagnetic fields and so on. The abnormal changes of groundwater such as well water before the earthquake are mainly manifested as sudden drop of water surface, discoloration and odor, flowering and bubbling, temperature fluctuation, sudden change of spring flow and sudden change of hot spring water temperature.
Earthquake records in Mudanjiang history
At 201612: 2219.0 seconds Beijing time, an earthquake of magnitude 6.4 occurred in linkou county, Mudanjiang City, Heilongjiang Province (44.8 1 degree north latitude, 0/29.95 degree east longitude) with a focal depth of 580 kilometers.
Distribution map of seismic zone