Parametrization of large scale 3D subsurface models – seismic velocities in the Eastern part of the North German Basin in the framework of the TUNB Velo 2.0 project

A harmonized regional 3D depth model of the subsurface for the North German Basin from Cenozoic to the base of Zechstein was developed from 2014 to 2020 in the framework of the TUNB project. In a next step, this model will be parametrized with a focus on seismic velocities (and optionally other parameters).

The seismic database in the former Eastern and Western parts of Germany differs due to different historical conditions (e.g. concepts of exploration and interpretation, availability of seismic equipment and computing power).

In the eastern part of the North German Basin (Federal States of Mecklenburg-Western Pomerania, Brandenburg, Saxony-Anhalt) most of the velocity data were acquired in 2D-seismic surveys from the 1960s to the 1980s that focused on deep Permian reservoirs. Strata and structure of the Mesozoic were also documented, but were usually not an exploration target. Besides processing velocities and in a minor extent sonic logs comprehensive data from check-shots and vertical seismic profiles were documented for several hundreds of wells. Based on these heterogeneous data, interpretations concepts and velocity models were developed from the 1960s to the 1980s on local scales for detailed seismic surveys and on regional scales for Northeastern Germany.

The main goal of the ongoing project is to develop workflows to revitalize the historical data with modern methods and possibilities of 3D modelling to derive cross-country-wide harmonized and seamless 3D-velocity fields. These velocity models allow large-scale depth-time- and time-depth-conversions of geological 3D models and support upcoming seismic processing and reprocessing campaigns.