Weathered and fractured limestone – a novel experimental approach allowing for better mapping of groundwater resources and mechanically unstable zones in the Öresund region

A typical aim of field-scale geophysics is to detect mechanically weak zones with damaged, fractured or weathered rock.

Despite this, geophysical laboratory research is only performed on solid rock cores due to technical/interpretational challenges with sampling and measurements on poor quality rocks.

Very little geoelectric research has focused on limestone materials due to their complex and varying microstructures which makes data interpretation challenging. This constitutes two major research gaps.

The objective of this project is to design, develop and use an advanced, novel and multi-physical experimental approach to study how electrical and acoustic signals evolves with the microstructure in various limestone samples during in-situ X-ray-tomography with mechanical compression or chemical dissolution.

In addition to a comprehensive analysis of microstructure-dependent physical mechanisms, the approach will also lead to quantitative knowledge about possible electro-mechanical couplings in the material.

The main aim is to increase the physical understanding of electrical and mechanical properties in different types of limestones, both unaffected, during the development of features such as fractures and preferential pore channels in mechanically weakening samples and ultimately on damaged rock material.

The results are expected to lead to more correct assessments of the bedrock in all types of construction- and environmental related projects in limestone environments.