The largest geothermal resources in the world are coupled with active plate
boundaries (e.g. Japan, New Zealand) and areas of extension and rift development such
as the African rift. However, geothermal resources are also observed in areas of
continent-continent collision. Hochstein and Regenauer-Lieb (1998) showed, that in
the India-Asia collision heat is discharged in 30-50km wide heat bands, that are
associated with more than 600 geothermal systems. These bands have been interpreted
as segments of major, concentric slip lines caused by plastic deformation within the
Asian plate resulting from the indentation of India into Asia. Assuming that this
crust behaves like an ideal plastic medium, the heat transfer within and along a slip
line can be estimated. It amounts to about 55 mW/m2 for a 40-km-wide band. Estimates
for present-day heat discharges point to 20–35 mW/m2 for convective, and 10–30 mW/m2
for anomalous conductive losses for a heated crustal strip in the greater Lhasa area.
Computed geotherms indicate that partial melting can develop at c. 30- to 50-km depth
within the heat bands.
Regenauer-Lieb et al. (subm.) showed that three different deformation modes fully
describe the large scale deformation during indentation: the vertical thickening, the
near-field indentation, and the far-field cutting mode. The heat lines in the
Himalayan Geothermal Belt are the outcome of the near-field indentation mode.
The far-field cutting of the European plate has been described by Regenauer-Lieb and
Petit (1997). Here we present new comparative analyses indicating that in central
Europe heat anomalies (e.g. the distribution of high temperatures at depth in the
Upper Rhine valley) can be related to the far-field cutting mode. These analyses
provide a new perspective in the validation of geothermal resources in central Europe.
Hochstein, M. and Regenauer-Lieb, K., 1998: Heat generation associated with collision
of two plates: the Himalayan Geothermal Belt. Journal of Volcanology and Geothermal
Research, 83, 75-92.
Regenauer-Lieb, K. and Petit, P.-J., 1997: Cutting of the European continental
lithosphere; plasticity theory applied to the present Alpine collision. Journal of
Geophysical Research, B, 102, 7731-7746.
Regenauer-Lieb, K., Schill, E. and Wiemer, S., subm: Analytical approaches to the
India-Asia indentation. Geology.