[en] Highlights: • Heat transfer characteristics were tested when sands with clay minerals. • Heat transfer characteristics were tested in different injected water temperature. • Then influence of clay mineral content on heat transfer characteristics was analyzed. -- Abstract: In this paper, a one-dimensional sand column experiment system was set up to study the heat transfer characteristics of brine aquifer, and the effective thermal diffusivity was calculated. In the conditions of different injected water temperatures and water head differences when the sand samples contained different kind of clay minerals and different contents, the temperature in sand column were tested. Based on the temperature change with time, the effective thermal diffusivities were obtained, also the function relationship between thermal diffusivity and injected temperature was obtained. Results indicate that the composition and content of clay minerals have the largest effect on the heat transfer performance of brine aquifer, followed by the temperature of injected water and the injected water head difference. For the three tested clay minerals, montmorillonite has the greatest influence on the heat transfer characteristics and the effective thermal diffusivity in the aquifer.