The algorithms for calculating the thermal flux in a rock mass at various mutual orientations of the principal axes of the thermal conductivity tensor and at various temperature gradients are considered. The experimental basis for determining the main components of the thermal conductivity tensor are described. The experimental study of thermal conductivity of about 1300 anisotropic rock samples taken from different geological objects showed that a substantial thermal anisotropy is rather widespread. At appreciable dip angles of mass beds and for a known anisotropy factor, the calculated thermal flux density depends, to a considerable extent, on a correct estimate of the temperature gradient orientation and on the choice of the pertinent model. The corrections are presented, which should be introduced into the conductive thermal flux previously evaluated from the Kola and KTB (Germany) overdeep borehole sections in depth intervals characterized by high anisotropy and steep dip angles of beds.
|Number of pages||13|
|Journal||Izvestiya, Physics of the Solid Earth|
|Publication status||Published - Nov 1998|