Rock density, radioelement content and rock thermal conductivity of rock from the ground surface and drilling holes within Zhangzhou region, southeast China were measured. The results show that the weighted mean value of rock density was 2.60 g/cm³, in good agreement with the average density of granite worldwide. The average radiogenic heat production of the investigated granite was 3.7 μW/m³, which is apparently higher than that of volcanic rock, mafic dykes and sedimentary rock from the same region. What is more, the main heat production was sourced from the decay of U and Th. The average rock thermal conductivity was 2.83 W/mK, approaching that of the middle-upper crustal rock. Our new data, together with previous geological, geophysical and geothermal data, indicate that the mantle contributes more heat flow than the crust to the surface heat flow, i.e., Q_m/Q_c>1, thus Zhangzhou region is a typical region with cold crust and hot mantle type lithospheric thermal regime.

Zhangzhou region  /  radiogenic heat production  /  thermal conductivity  /  cold crust and hot mantle