[S24-P] Poster

[S24-P-01] Thermal properties of sedimentary rocks for the Tarim Basin, northwest China

^○Shaowen Liu^{1, 2}, Xianglan Li^{1, 2}, Changge Feng^1,2 (1.Nanjing University, Nanjing, China, 2.Key Laboratory of Coast and Island Development, Nanjing University, Nanjing, China)

Thermal properties of rocks are essential parameters for investigating geothermal regime of the sedimentary basins, also playing an important role in hydrocarbon and geothermal energy resources assessment. Tarim Basin that locates at northwest China, just north of the Tibet Plateau, has shown great hydrocarbon resource potential, and is the ongoing target for industry exploration. However, systematic measurement of thermal properties of sedimentary rocks for the Tarim Basin is still rare, making the understanding of thermal regime of this basin not well. Herein we collected 114 samples of sedimentary rocks from this basin and measured their complete thermal properties. Our results show that the ranges (and means) of the thermal conductivity, radiogenic heat production, and specific heat capacity are from 1.000 to 3.000W/m.K (2.446 W/m.K), 0.027 to 2.500 HPU (1.210 HPU), and 0.75 to 1.10 kJ/ (kg.K) (0.863 kJ/ (kg.K)), respectively. The calculated volumetric heat (or thermal) capacity and thermal diffusivity fall within the ranges from 1.61 to 2.79 MJ/ (cubic meters·K) (2.26 MJ/ (cubic meters·K)) and from 0.22 to 3.05 unit (1.11 unit), respectively. In addition, it is found that these thermal properties show great differences in various lithologies; even within the same lithology, the values scatter much. This indicates that the thermal properties cannot be used to distinguish lithology alone in practice. The thermal conductivity increases with increasing burial depth and stratigraphic age, suggestive of the influence of change in porosities on thermal conductivity. The specific heat capacity increases with the elevated temperature from 40 to 100 degree Celsius. Furthermore, strong contrast in thermal properties between salt and other common sedimentary rocks would obviously distort subsurface temperature pattern, which should be taken into consideration in basin modelling.