Abstract: On the basis of analysis on heat system of well-aquifer, combining with practical observation results of well water temperature behaviors, two mechanisms of water-heat dynamics and earth-heat dynamics of well water temperature micro-behavior are presented. The mechanism of water-heat dynamics is that the well water temperature micro-behavior originates from heat transport related to moving of water flow. The mechanism of earth-heat dynamics is that the well water temperature micro-behavior originates from heat flow or heat transfer in the earth. Results show that most coseismic responses of water temperature in a well are micro-behaviors produced under water-heat dynamics mechanism, whereas post-seismic effects or changes of water temperature in a well are micro-behaviors caused by heat conduction or change of deep heat flow, and belong to earth-heat dynamics mechanism. The characteristics of a few micro-behaviors of water temperature in a well are more complicated, which is due to existence of multilayer aquifers in a well-aquifer system. And the hydrogeological characteristics of these aquifers are more obviously different, which cannot be yet explained under the mechanisms of water-heat or earth-heat dynamics.