Field investigation

Taking groundwater, salinization, groundwater levels, soil, interaction between vadose zone and saturated zone into the consideration of simulation models special (geophysical) techniques are needed to learn more about the subsurface. These special techniques and field investigations are applied in different pilot areas. The acquired data contribute to geological and hydrological 3D models.

Objectives are:

• Development, innovation and practical testing of newest technology with the aim to identify geological layers and soil characteristics, salinity, pathways for salinity or nutrients/pollution, hydraulic properties.
• Joint development and implementation of an investigation plan for each pilot.

The investigations are done via staff exchange and close cooperation between the lead of the pilot area and the investigation team.

This will include a Transnational Peer Review ( TPR) for each pilot at the start and at various stages during the project in order to identify transnational synergies, collaborative opportunities, and maximize project delivery.

• Development and application of workflows for data processing and identification and preparation of parameters for the geological and hydrological models.
• Solid climate change adaptation needs a reliable database, shared databases and dissemination of results.

Structures and processes in the subsurface beneath our feet must be known for proper management of soil and water. Overview measurements like SkyTEM were carried out in some pilots and give, e.g., the distribution of freshwater and saltwater in the aquifers, while other pilots use results from airborne electromagnetic measurements by BGR (Federal Institute for Geosciences and Natural Resources) prior to the project start for an interpretation in terms of groundwater conditions. In some pilots the tTEM system newly developed by HydroGeophysics Group Aarhus University was applied to provide resistivity information in the target depth range of 0–70 m. Methods to relate the resistivity distribution in the aquifer covering layers to clay content and hydraulic conductivity for an assessment of groundwater protection and recharge are under development.

The approach and results of all activities will be published in a special issue of a scientific journal. The work is done in close cooperation with the other WPs, especially WP 3 and 5. The work builds on different knowledge and new perspectives from beneficiaries.

Leibniz Institute for Applied Geophysics is responsible for Work package 4.