Heat production rate of deep rocks in Bohai Bay Basin and its relationship with terrestrial heat flow

Abstract

The vertical distribution of rocks’ radioactive heat production rate in the continental crust is the basis for exploring the deep thermal structure and explaining terrestrial heat flow distribution characteristics. In this paper, taking the Bohai Bay Basin as an example, according to the content of U, Th and K in the rocks and the lithologic composition of each structural layer of the crust, calculating the range of radioactive heat-generating elements in each structural layer. Then, systematically analyze the distribution characteristics of heat production rate in the crust. Finally, establish the vertical distribution model of heat production rate and discuss the relationship between heat flow and heat production rate. The results show that the rock heat production rate is mainly related to lithology. U and Th are primarily enriched in the upper crust with exponential distribution, while K content is unchanged. Under exponential crustal heat production rate distribution, the D_U, D_Th and D_A in the crust are 15.195 km, 15.29 km and 21.11 km, respectively. A linear relationship exists between heat flow and heat production rate but cannot infer the thermal condition of the middle and lower crust.