Heat flow data at station HF1621 during RV SONNE cruise SO247

We used the 6 m long Bremen heat flow probe also called Giant Heat Flow Probe (GHF). The heat probe is constructed in the classical “violin bow” design (Hyndman et al., 1979; Hartmann and Villinger, 2002, Villinger et al., 2010), with 21 thermistors distributed over an active length of 5.2 m in 0.26 m intervals mounted inside an oil filled hydraulic tube (O.D. 14 mm) which is attached to the strength member (O.D. 130 mm). The sensor tube also contains a heater wire for the generation of high energy heat pulses of typically on the order of 800 J/m for in situ thermal conductivity measurements according to the pulsed needle probe method (Lister, 1979). A calibrated PT-100 seawater sensor on top of the weight stand allows to measure the absolute bottom water temperature and to check the calibration of the sensor string in deep water with high accuracy. Inclination and acceleration of the probe is measured to monitor the penetration process into the sediments and potential disturbances during the actual measurement period