Influence of Shallow Factors on Terrestrial Heat Flow in Regional Geothermal Field Studies

Surface heat flow serves as a critical parameter in geophysical studies, particularly for estimating crustal temperatures, modelling the thermal structure of the lithosphere, and conducting geodynamic analyses. Therefore, accurately assessing the reliability of heat flow measurements is of significant importance. In this study, based on hydrothermal coupling and combining the simplified calculation model, the influence of thermal refraction, water‐flowing fractures, and groundwater convection on the surface heat flow value was analysed. Generally, as the buried depth of these shallow influencing factors increases, their impact diminishes considerably. Regarding the thermal refraction resulting from lateral variations in the thermal conductivity, as the angle of the thermal refraction profile increases, its influence on the surface heat flow becomes more pronounced. As the thickness of the fractures increased, their influence on the surrounding area became more pronounced. As for groundwater convection, the heat flow is diminished in the recharge zone owing to the infiltration of atmospheric precipitation, and the heat flow surges abnormally high in the discharge zone owing to the emergence of underground hot water. Furthermore, the influence of groundwater convection on the shallow temperature field gradually weakens as either the permeability of the aquifer is reduced or the depth of burial increases.