Preface The expedition ARK XIX/3 with the German icebreaking RV ...

the picture of a recently active mud volcano. From long gravity cores the bending of
gradients becomes obvious (see below).
Figure B3.1.1-1: Temperature gradient of centre location is 2.5°C/m, mean thermal
conductivity is 1 W/m K. Temperature at shallowest sensor is more than 9°C.
The limit of the volcano is very distinct and associated with a horizontal temperature
gradient of app. 10°C per 100 m. Beyond 200 m from the rim of HMMV (i.e. 600 m
from the centre) almost no thermal signal of the mud volcano can be detected.
In many cases but not all thermal gradients are not linear but curved in a convex
shape. This gives reason to suggest upward convective heat flow by fluid transport of
considerable amount.
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