Heat Flow Products

Classical Heat Flow

The Heat Flow Probe is an instrument for the measurement of the thermal gradient and the thermal conductivity. With both parameters the heat flux density can be determined. The instrument is capable to measure in-situ values with 22 sensors down to a depth of 6 m below the seafloor. Besides the temperature sensor string, an extra heating wire is attached to the probe. That wire provides a heat pulse for the measurement of thermal conductivity. In summary the temperature gradient is measured along 22 points with a resolution of 0.001 K and in addition 22 in-situ values of thermal conductivity, and hence, the heat flux density is determined in one go.

Download Flyer HeatFlowProbe (engl.) (pdf-file)

Heat Flow Probe Plus: Latest 2016 version
Download Flyer HeatFlowProbe Plus (engl.) (pdf-file)


For in-situ temperature and thermal conductivity measurements in shear resistant marine sediments, typical for shallow seas, coastal and continental shelf regions, FIELAX GmbH combined the functional components of the FIELAX HeatFlowProbe with a VKG6 type Vibrocorer. We name this new measuring device “VibroHeat”. With the ability to penetrate even through harsh layers such as gas hydrates, permafrost soils or “sands”, the technical application is not restricted to soft sediment conditions anymore.

Download Flyer VibroHeat (engl.) (pdf-Datei)


In cooperation with Marine Sampling Holland, FIELAX has further developed its heat flow measurement system to work with a CPT unit used for in-situ geotechnical measurements, in order to overcome possible liquefaction, which may occur in very sandy sediments due to the vibrocoring. Therefore the sensorstring was adapted to fit into a standard coiled CPT-tube of 6 m length i.e. the number of temperature sensors was reduced to 13 temperature sensors at a spacing of 42 cm. Read more…

Temperature Gradient Probe

The Temperature Gradient Probe measures temperature profiles in the sediment with temperature loggers mounted along a massive steel lance. The data acquisition using those loggers is operating in an autonomous way. The robust layout of the probe provides a large penetration depth of more than 5 m, quite more than with conventional instruments in use today. With this penetration depth reliable results are achieved and the uppermost, thermal disturbed, sediments are not falsifying the experiment.