FINA - Kleine Restlochkette Finsterwalde - Interpretation of airborne geophysical investigation results

Country / Region: Germany/Brandenburg/Lausatia

Begin of project: July 1, 2022

End of project: June 30, 2024

Status of project: July 6, 2023

Airborne geophysical survey area between Finsterwalde and Lauchhammer (Lower Lusatia, Germany) Source: BGR

The goal of the FINA project is to develop a 3D subsurface model by using airborne electromagnetic data and lithological drilling records. In the BGR pilot study D-AERO-Finsterwalde, airborne geophysical investigations of the post-mining landscape Finsterwalde Restlochkette were carried out in summer 2021. The D-AERO-Finsterwalde study focused on the investigation of groundwater level and mineralisation around previous open mine dumps by evaluating the collected airborne geophysical measurements.
We will use both interpretative-geological which is solely based on the borehole data as well as a machine-learning approach to model complex subsurface structures of the Finsterwalde Restlochkette. Around the Finsterwalde Restlochkette Cenozoic sediments, including lignite seams and extensive open pit dumps, form a complex lithological sequence. To learn more about the geological underground of post-mining landscapes we will combine aero-geophysical data with borehole data to create a 3D subsurface model. The machine-learning based approach will integrate spatial information from airborne geophysics and drilling data into a 3D subsurface model of the near-surface groundwater systems. For each approach, respective workflows will be developed.
Primarily, we will evaluate the uncertainties of both workflows for the construction of the 3D subsurface models using statistical methods. Subsequently, we will compare the 3D subsurface models with the parameter sets from the calibrated numerical flow model.
In addition, we will compare the geophysical data from the helicopter with those from drone surveys. The evaluation of the differences in resolution and quality of both methods will contribute to better planning future airborne investigations of post-mining landscapes.

Project aims:

• Developing a workflow to derive a 3D subsurface model based on drilling and other geological data by with a hands-on approach
• Developing a workflow for the integration of aero-geophysical model and drilling data into a 3D subsurface model using machine learning
• Evaluating the workflows by using the derived 3D subsurface models in numerical flow models

Partner:

• Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft (LMBV), Knappenstraße 1, 01968 Senftenberg (Germany)
• Landesamt für Bergbau, Geologie und Rohstoffe Brandenburg (LBGR), Inselstraße 26, 03046 Cottbus (Germany)