Thermal structure beneath the Mt. Changbai Volcanic Area, northeastern Asia: New insights from temperature logging and numerical modeling
1. Temperature logs The well temperature was measured by a cable system consisting of a thermistor (max. temperature 350 °C) and a 5000-m cable. This system is manufactured by Pioneer Petrotech Services, Canada, and allows the temperature to be continuously recorded with a sensitivity of 0.01 C, a limiting accuracy of 0.1 C and a depth interval of 0.05 m. The four wells had sufficiently long shut-in times (the time elapsed after the cessation of drilling) for the temperature to recover. Well C-1, approximately 7 km north of the caldera center, is almost within the Tianchi caldera, whereas the other three wells are approximately 20 km to 60 km from the caldera. The measured data are listed in Dataset s1-s4. 2. Thermophysical parameters We measured the thermal conductivities and concentrations of heat-producing elements (Th, U, and K) in 19 core samples (from wells C-2 and C-3) and 12 outcrop samples (near wells C-1 and C-4) extracted from the representative lithologies of the four wells. The measured data are listed in Dataset s5. Dataset S1. The temperature logs of C-1. Dataset S2. The temperature logs of C-2. Dataset S3. The temperature logs of C-3. Dataset S4. The temperature logs of C-4. Dataset S5. The measured thermal conductivity, U-Th-K concentration and heat production.
National Natural Science Foundation of China