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The present day’s thermal lithospheric thickness is usually calculated by one or two-dimensional steady-state heat conduction equation. Using the latest measured heat flow data of the North China Craton(NCC) and the one-dimensional steady-state heat conduction equation, the calculated thermal lithospheric thickness of the NCC is between 34.8-190 km. There are some regions, whose lithosphere is very thin, and the lithosphere adjacent to them is very thick, so the bottom boundary of the lithosphere fluctuates greatly. The last thinning of the NCC stopped at~24 Ma and then entered the thermal subsidence period. To study whether the fluctuates of the bottom boundary of the lithosphere can be maintained during the long-term thermal subsidence process, a thermal subsidence model was established. The modeling results show that after the thermal subsidence of 24 Ma, the fluctuates of the bottom boundary of the lithosphere are difficult to maintain, and the present day’s thermal lithospheric thickness of the NCC should not exceed 73 km, and the maximum surface heat flow value of the NCC is 75.6 mW·m-2 due to the deep thermal state. The high heat flows anomaly in the NCC is more caused by shallow activities and cannot reflect the deep thermal state. After correction, the current thermal lithospheric thickness of the North China craton is ~73-190 km, and the bottom boundary of the lithosphere changes gently., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Sichuan Basin is an important hydrocarbon-bearing basin in China, and its southwestern part is located in the outer zone of the Emeishan Large Igneous Province. The thermal influence of Emeishan basalt on hydrocarbon development in the Sichuan Basin has been of great interest. Recent paleo-heat flow recovery calculations have yielded the presence of high paleo-heat flows greater than 100 mW/m2 duirng the Permian at some points in the basin, which are thought to be related to Emeishan basalt. In order to understand the causes of these high paleo-heat flows and the thermal effects of basaltic magma overflowing to the surface on the lower strata, the thermal effects of Emeishan basalt were simulated by 2D finite element method. The following conclusions are drawn: (1) The changes in surface heat flow generated by the intrusion of Emeishan basaltic magma into the bottom of the lithosphere and the bottom of the crust are both inconsistent with the high paleo-heat flow of >100 mW/m2 during the Permian of the Sichuan Basin, and magma intruded into the interior of the crust can cause such high paleo-heat flows.(2) The thermal disturbance caused by different thicknesses of magma at the surface to the lower strata at different depths was calculated. The thicker the magma at the surface and the shallower the overlying strata, the greater the thermal disturbance of the magma to the strata, while the adjacent strata are unaffected. The thermal influence on the hydrocarbon source rocks can thus be inferred., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

To improve the quality and efficiency of inspection tasks, this paper studies the path planning optimization strategy for distribution equipment inspection of distribution networks. The comprehensive information model of each type of distribution equipment to be inspected is established by integrating the real-time monitoring information, geographic information and historic information effectively. The inspection path optimization model with an admissible cost function is established and solved by using the heuristic search A* algorithm. Comparison of the results of several inspection path planning strategies are provided to verify the effectiveness of the proposed strategy.