Temperature measurement data from boreholes at the Southwestern Margin of the Huangling Dome

Temperature logs were obtained from seven boreholes (ZK1–ZK7) drilled for engineering investigation. Borehole depths range from 220 to 1010.4 m, which allows for capturing steady-state geothermal gradients at sufficient depths, minimizing influences from shallow, transient temperature fluctuations. Temperature logging was conducted using a miniaturized temperature data logger made by Fa. Antares and the University of Breme. The instrument, calibrated to a resolution of 1 mK and an accuracy of 0.1 K, was selected to meet the requirements for the precise detection of subtle subsurface temperature variations. All measured borehole intervals were below the groundwater level. Measurements were taken at intervals of 5 or 10 m to sample the temperature profiles. Limited by factors such as the measuring cable length and borehole collapse, some boreholes were not logged to the bottom. The maximum measurement depth is 780 m. To ensure the reliability of the temperature data, all boreholes were left undisturbed for more than 22 days before logging to minimize the disturbance of drilling activities on the temperature profiles. Among them, the ZK4 borehole exhibited the longest shut-in time, exceeding 3.5 years.