Terrestrial heat flow and heat controlling factors in the northeastern Tibetan Plateau: A case study of Gonghe Basin

Gonghe Basin in the northeastern Tibetan Plateau recently discovered high-temperature Hot Dry Rock (HDR) in its deep part. Investigating the basin's heat flow distribution is crucial for understanding the HDR genesis mechanism. We conducted 24 borehole temperature logs and 240 thermal conductivity measurements on rock cores, supplementing 14 new heat flow data. From these data, we generated geothermal gradient and heat flow maps, analyzing the primary factors influencing the regional heat flow. The results show an average geothermal gradient of 48.52 ± 19.36 °C/km, with heat flow values ranging from 51.00 to 134.66 mW/m2 (mean of 90.56 ± 22.18 mW/m2). The basin is classified as a hot basin, with heat flow exhibiting a distribution trend of high in the northeast and low in the west, demonstrating significant longitudinal heterogeneity. An in-depth analysis of heat flow maps reveals a strong spatial correlation between low-resistivity anomaly zones and heat flow distribution, highlighting low-resistance channels and fault zones as key conduits for rapid heat transfer from deep to shallow layers. Additionally, different low-resistivity anomaly zones contribute variably to regional heat flow. In areas with a relatively shallow basement depth, heat accumulation is pronounced, resulting in higher heat flow values. This study provides novel insights and a scientific basis for further investigation into the genesis of geothermal anomalies and the distribution of heat sources in the Gonghe Basin.