Modeling of the 3D thermal field in the northeast German basin

Abstract

 The regional thermal field of the NE-German basin is modeled by a three-dimensional finite-element approach and is compared to classical one-dimensional extrapolations. Two alternative boundary conditions are assumed at the approximate depth of the Moho: a constant temperature distribution and a constant heat flow. Surprisingly, both results are almost identical down to approximately 10 km depth. Based on the models presented, the results are due to a complex interaction of different strata and the related regional variability of conductivities. In addition, the available temperature maps for different depths (Hurtig et al. 1992) indicate a relative high heat flow at the basin margins especially at the southern and eastern boundary. The models are able to reproduce the generalized pattern by regarding only a conductive heat flow. However, because both models are successful at shallow depth, we conclude that the current techniques of thermal modeling require improvement, even on the theoretical aspects of depth continuation and inversion.